Fixed MTP to work with TWRP

arch/arm/common/Kconfig

@@ -0,0 +1,26 @@
+config ICST
+	bool
+
+config SA1111
+	bool
+	select DMABOUNCE if !ARCH_PXA
+
+config DMABOUNCE
+	bool
+	select ZONE_DMA
+
+config SHARP_LOCOMO
+	bool
+
+config SHARP_PARAM
+	bool
+
+config SHARP_SCOOP
+	bool
+
+config TI_PRIV_EDMA
+	bool
+
+config FIQ_GLUE
+	bool
+	select FIQ

arch/arm/common/Makefile

@@ -0,0 +1,22 @@
+#
+# Makefile for the linux kernel.
+#
+
+obj-y				+= firmware.o
+
+obj-$(CONFIG_FIQ_GLUE)		+= fiq_glue.o fiq_glue_setup.o
+obj-$(CONFIG_ICST)		+= icst.o
+obj-$(CONFIG_SA1111)		+= sa1111.o
+obj-$(CONFIG_DMABOUNCE)		+= dmabounce.o
+obj-$(CONFIG_SHARP_LOCOMO)	+= locomo.o
+obj-$(CONFIG_SHARP_PARAM)	+= sharpsl_param.o
+obj-$(CONFIG_SHARP_SCOOP)	+= scoop.o
+obj-$(CONFIG_PCI_HOST_ITE8152)  += it8152.o
+obj-$(CONFIG_ARM_TIMER_SP804)	+= timer-sp.o
+obj-$(CONFIG_MCPM)		+= mcpm_head.o mcpm_entry.o mcpm_platsmp.o vlock.o
+CFLAGS_REMOVE_mcpm_entry.o	= -pg
+AFLAGS_mcpm_head.o		:= -march=armv7-a
+AFLAGS_vlock.o			:= -march=armv7-a
+obj-$(CONFIG_TI_PRIV_EDMA)	+= edma.o
+obj-$(CONFIG_BL_SWITCHER)	+= bL_switcher.o
+obj-$(CONFIG_BL_SWITCHER_DUMMY_IF) += bL_switcher_dummy_if.o

arch/arm/common/bL_switcher.c

@@ -0,0 +1,814 @@
+/*
+ * arch/arm/common/bL_switcher.c -- big.LITTLE cluster switcher core driver
+ *
+ * Created by:	Nicolas Pitre, March 2012
+ * Copyright:	(C) 2012-2013  Linaro Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/atomic.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/cpu_pm.h>
+#include <linux/cpu.h>
+#include <linux/cpumask.h>
+#include <linux/kthread.h>
+#include <linux/wait.h>
+#include <linux/time.h>
+#include <linux/clockchips.h>
+#include <linux/hrtimer.h>
+#include <linux/tick.h>
+#include <linux/notifier.h>
+#include <linux/mm.h>
+#include <linux/mutex.h>
+#include <linux/smp.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include <linux/irqchip/arm-gic.h>
+#include <linux/moduleparam.h>
+
+#include <asm/smp_plat.h>
+#include <asm/cputype.h>
+#include <asm/suspend.h>
+#include <asm/mcpm.h>
+#include <asm/bL_switcher.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/power_cpu_migrate.h>
+
+
+/*
+ * Use our own MPIDR accessors as the generic ones in asm/cputype.h have
+ * __attribute_const__ and we don't want the compiler to assume any
+ * constness here as the value _does_ change along some code paths.
+ */
+
+static int read_mpidr(void)
+{
+	unsigned int id;
+	asm volatile ("mrc p15, 0, %0, c0, c0, 5" : "=r" (id));
+	return id & MPIDR_HWID_BITMASK;
+}
+
+/*
+ * bL switcher core code.
+ */
+
+static void bL_do_switch(void *_arg)
+{
+	unsigned ib_mpidr, ib_cpu, ib_cluster;
+	long volatile handshake, **handshake_ptr = _arg;
+
+	pr_debug("%s\n", __func__);
+
+	ib_mpidr = cpu_logical_map(smp_processor_id());
+	ib_cpu = MPIDR_AFFINITY_LEVEL(ib_mpidr, 0);
+	ib_cluster = MPIDR_AFFINITY_LEVEL(ib_mpidr, 1);
+
+	/* Advertise our handshake location */
+	if (handshake_ptr) {
+		handshake = 0;
+		*handshake_ptr = &handshake;
+	} else
+		handshake = -1;
+
+	/*
+	 * Our state has been saved at this point.  Let's release our
+	 * inbound CPU.
+	 */
+	mcpm_set_entry_vector(ib_cpu, ib_cluster, cpu_resume);
+	sev();
+
+	/*
+	 * From this point, we must assume that our counterpart CPU might
+	 * have taken over in its parallel world already, as if execution
+	 * just returned from cpu_suspend().  It is therefore important to
+	 * be very careful not to make any change the other guy is not
+	 * expecting.  This is why we need stack isolation.
+	 *
+	 * Fancy under cover tasks could be performed here.  For now
+	 * we have none.
+	 */
+
+	/*
+	 * Let's wait until our inbound is alive.
+	 */
+	while (!handshake) {
+		wfe();
+		smp_mb();
+	}
+
+	/* Let's put ourself down. */
+	mcpm_cpu_power_down();
+
+	/* should never get here */
+	BUG();
+}
+
+/*
+ * Stack isolation.  To ensure 'current' remains valid, we just use another
+ * piece of our thread's stack space which should be fairly lightly used.
+ * The selected area starts just above the thread_info structure located
+ * at the very bottom of the stack, aligned to a cache line, and indexed
+ * with the cluster number.
+ */
+#define STACK_SIZE 512
+extern void call_with_stack(void (*fn)(void *), void *arg, void *sp);
+static int bL_switchpoint(unsigned long _arg)
+{
+	unsigned int mpidr = read_mpidr();
+	unsigned int clusterid = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+	void *stack = current_thread_info() + 1;
+	stack = PTR_ALIGN(stack, L1_CACHE_BYTES);
+	stack += clusterid * STACK_SIZE + STACK_SIZE;
+	call_with_stack(bL_do_switch, (void *)_arg, stack);
+	BUG();
+}
+
+/*
+ * Generic switcher interface
+ */
+
+static unsigned int bL_gic_id[MAX_CPUS_PER_CLUSTER][MAX_NR_CLUSTERS];
+static int bL_switcher_cpu_pairing[NR_CPUS];
+
+/*
+ * bL_switch_to - Switch to a specific cluster for the current CPU
+ * @new_cluster_id: the ID of the cluster to switch to.
+ *
+ * This function must be called on the CPU to be switched.
+ * Returns 0 on success, else a negative status code.
+ */
+static int bL_switch_to(unsigned int new_cluster_id)
+{
+	unsigned int mpidr, this_cpu, that_cpu;
+	unsigned int ob_mpidr, ob_cpu, ob_cluster, ib_mpidr, ib_cpu, ib_cluster;
+	struct completion inbound_alive;
+	struct tick_device *tdev;
+	enum clock_event_mode tdev_mode;
+	long volatile *handshake_ptr;
+	int ipi_nr, ret;
+
+	this_cpu = smp_processor_id();
+	ob_mpidr = read_mpidr();
+	ob_cpu = MPIDR_AFFINITY_LEVEL(ob_mpidr, 0);
+	ob_cluster = MPIDR_AFFINITY_LEVEL(ob_mpidr, 1);
+	BUG_ON(cpu_logical_map(this_cpu) != ob_mpidr);
+
+	if (new_cluster_id == ob_cluster)
+		return 0;
+
+	that_cpu = bL_switcher_cpu_pairing[this_cpu];
+	ib_mpidr = cpu_logical_map(that_cpu);
+	ib_cpu = MPIDR_AFFINITY_LEVEL(ib_mpidr, 0);
+	ib_cluster = MPIDR_AFFINITY_LEVEL(ib_mpidr, 1);
+
+	pr_debug("before switch: CPU %d MPIDR %#x -> %#x\n",
+		 this_cpu, ob_mpidr, ib_mpidr);
+
+	this_cpu = smp_processor_id();
+
+	/* Close the gate for our entry vectors */
+	mcpm_set_entry_vector(ob_cpu, ob_cluster, NULL);
+	mcpm_set_entry_vector(ib_cpu, ib_cluster, NULL);
+
+	/* Install our "inbound alive" notifier. */
+	init_completion(&inbound_alive);
+	ipi_nr = register_ipi_completion(&inbound_alive, this_cpu);
+	ipi_nr |= ((1 << 16) << bL_gic_id[ob_cpu][ob_cluster]);
+	mcpm_set_early_poke(ib_cpu, ib_cluster, gic_get_sgir_physaddr(), ipi_nr);
+
+	/*
+	 * Let's wake up the inbound CPU now in case it requires some delay
+	 * to come online, but leave it gated in our entry vector code.
+	 */
+	ret = mcpm_cpu_power_up(ib_cpu, ib_cluster);
+	if (ret) {
+		pr_err("%s: mcpm_cpu_power_up() returned %d\n", __func__, ret);
+		return ret;
+	}
+
+	/*
+	 * Raise a SGI on the inbound CPU to make sure it doesn't stall
+	 * in a possible WFI, such as in bL_power_down().
+	 */
+	gic_send_sgi(bL_gic_id[ib_cpu][ib_cluster], 0);
+
+	/*
+	 * Wait for the inbound to come up.  This allows for other
+	 * tasks to be scheduled in the mean time.
+	 */
+	wait_for_completion(&inbound_alive);
+	mcpm_set_early_poke(ib_cpu, ib_cluster, 0, 0);
+
+	/*
+	 * From this point we are entering the switch critical zone
+	 * and can't take any interrupts anymore.
+	 */
+	local_irq_disable();
+	local_fiq_disable();
+	trace_cpu_migrate_begin(ktime_get_real_ns(), ob_mpidr);
+
+	/* redirect GIC's SGIs to our counterpart */
+	gic_migrate_target(bL_gic_id[ib_cpu][ib_cluster]);
+
+	tdev = tick_get_device(this_cpu);
+	if (tdev && !cpumask_equal(tdev->evtdev->cpumask, cpumask_of(this_cpu)))
+		tdev = NULL;
+	if (tdev) {
+		tdev_mode = tdev->evtdev->mode;
+		clockevents_set_mode(tdev->evtdev, CLOCK_EVT_MODE_SHUTDOWN);
+	}
+
+	ret = cpu_pm_enter();
+
+	/* we can not tolerate errors at this point */
+	if (ret)
+		panic("%s: cpu_pm_enter() returned %d\n", __func__, ret);
+
+	/* Swap the physical CPUs in the logical map for this logical CPU. */
+	cpu_logical_map(this_cpu) = ib_mpidr;
+	cpu_logical_map(that_cpu) = ob_mpidr;
+
+	/* Let's do the actual CPU switch. */
+	ret = cpu_suspend((unsigned long)&handshake_ptr, bL_switchpoint);
+	if (ret > 0)
+		panic("%s: cpu_suspend() returned %d\n", __func__, ret);
+
+	/* We are executing on the inbound CPU at this point */
+	mpidr = read_mpidr();
+	pr_debug("after switch: CPU %d MPIDR %#x\n", this_cpu, mpidr);
+	BUG_ON(mpidr != ib_mpidr);
+
+	mcpm_cpu_powered_up();
+
+	ret = cpu_pm_exit();
+
+	if (tdev) {
+		clockevents_set_mode(tdev->evtdev, tdev_mode);
+		clockevents_program_event(tdev->evtdev,
+					  tdev->evtdev->next_event, 1);
+	}
+
+	trace_cpu_migrate_finish(ktime_get_real_ns(), ib_mpidr);
+	local_fiq_enable();
+	local_irq_enable();
+
+	*handshake_ptr = 1;
+	dsb_sev();
+
+	if (ret)
+		pr_err("%s exiting with error %d\n", __func__, ret);
+	return ret;
+}
+
+struct bL_thread {
+	spinlock_t lock;
+	struct task_struct *task;
+	wait_queue_head_t wq;
+	int wanted_cluster;
+	struct completion started;
+	bL_switch_completion_handler completer;
+	void *completer_cookie;
+};
+
+static struct bL_thread bL_threads[NR_CPUS];
+
+static int bL_switcher_thread(void *arg)
+{
+	struct bL_thread *t = arg;
+	struct sched_param param = { .sched_priority = 1 };
+	int cluster;
+	bL_switch_completion_handler completer;
+	void *completer_cookie;
+
+	sched_setscheduler_nocheck(current, SCHED_FIFO, &param);
+	complete(&t->started);
+
+	do {
+		if (signal_pending(current))
+			flush_signals(current);
+		wait_event_interruptible(t->wq,
+				t->wanted_cluster != -1 ||
+				kthread_should_stop());
+
+		spin_lock(&t->lock);
+		cluster = t->wanted_cluster;
+		completer = t->completer;
+		completer_cookie = t->completer_cookie;
+		t->wanted_cluster = -1;
+		t->completer = NULL;
+		spin_unlock(&t->lock);
+
+		if (cluster != -1) {
+			bL_switch_to(cluster);
+
+			if (completer)
+				completer(completer_cookie);
+		}
+	} while (!kthread_should_stop());
+
+	return 0;
+}
+
+static struct task_struct *bL_switcher_thread_create(int cpu, void *arg)
+{
+	struct task_struct *task;
+
+	task = kthread_create_on_node(bL_switcher_thread, arg,
+				      cpu_to_node(cpu), "kswitcher_%d", cpu);
+	if (!IS_ERR(task)) {
+		kthread_bind(task, cpu);
+		wake_up_process(task);
+	} else
+		pr_err("%s failed for CPU %d\n", __func__, cpu);
+	return task;
+}
+
+/*
+ * bL_switch_request_cb - Switch to a specific cluster for the given CPU,
+ *      with completion notification via a callback
+ *
+ * @cpu: the CPU to switch
+ * @new_cluster_id: the ID of the cluster to switch to.
+ * @completer: switch completion callback.  if non-NULL,
+ *	@completer(@completer_cookie) will be called on completion of
+ *	the switch, in non-atomic context.
+ * @completer_cookie: opaque context argument for @completer.
+ *
+ * This function causes a cluster switch on the given CPU by waking up
+ * the appropriate switcher thread.  This function may or may not return
+ * before the switch has occurred.
+ *
+ * If a @completer callback function is supplied, it will be called when
+ * the switch is complete.  This can be used to determine asynchronously
+ * when the switch is complete, regardless of when bL_switch_request()
+ * returns.  When @completer is supplied, no new switch request is permitted
+ * for the affected CPU until after the switch is complete, and @completer
+ * has returned.
+ */
+int bL_switch_request_cb(unsigned int cpu, unsigned int new_cluster_id,
+			 bL_switch_completion_handler completer,
+			 void *completer_cookie)
+{
+	struct bL_thread *t;
+
+	if (cpu >= ARRAY_SIZE(bL_threads)) {
+		pr_err("%s: cpu %d out of bounds\n", __func__, cpu);
+		return -EINVAL;
+	}
+
+	t = &bL_threads[cpu];
+
+	if (IS_ERR(t->task))
+		return PTR_ERR(t->task);
+	if (!t->task)
+		return -ESRCH;
+
+	spin_lock(&t->lock);
+	if (t->completer) {
+		spin_unlock(&t->lock);
+		return -EBUSY;
+	}
+	t->completer = completer;
+	t->completer_cookie = completer_cookie;
+	t->wanted_cluster = new_cluster_id;
+	spin_unlock(&t->lock);
+	wake_up(&t->wq);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(bL_switch_request_cb);
+
+/*
+ * Activation and configuration code.
+ */
+
+static DEFINE_MUTEX(bL_switcher_activation_lock);
+static BLOCKING_NOTIFIER_HEAD(bL_activation_notifier);
+static unsigned int bL_switcher_active;
+static unsigned int bL_switcher_cpu_original_cluster[NR_CPUS];
+static cpumask_t bL_switcher_removed_logical_cpus;
+
+int bL_switcher_register_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&bL_activation_notifier, nb);
+}
+EXPORT_SYMBOL_GPL(bL_switcher_register_notifier);
+
+int bL_switcher_unregister_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_unregister(&bL_activation_notifier, nb);
+}
+EXPORT_SYMBOL_GPL(bL_switcher_unregister_notifier);
+
+static int bL_activation_notify(unsigned long val)
+{
+	int ret;
+
+	ret = blocking_notifier_call_chain(&bL_activation_notifier, val, NULL);
+	if (ret & NOTIFY_STOP_MASK)
+		pr_err("%s: notifier chain failed with status 0x%x\n",
+			__func__, ret);
+	return notifier_to_errno(ret);
+}
+
+static void bL_switcher_restore_cpus(void)
+{
+	int i;
+
+	for_each_cpu(i, &bL_switcher_removed_logical_cpus) {
+		struct device *cpu_dev = get_cpu_device(i);
+		int ret = device_online(cpu_dev);
+		if (ret)
+			dev_err(cpu_dev, "switcher: unable to restore CPU\n");
+	}
+}
+
+static int bL_switcher_halve_cpus(void)
+{
+	int i, j, cluster_0, gic_id, ret;
+	unsigned int cpu, cluster, mask;
+	cpumask_t available_cpus;
+
+	/* First pass to validate what we have */
+	mask = 0;
+	for_each_online_cpu(i) {
+		cpu = MPIDR_AFFINITY_LEVEL(cpu_logical_map(i), 0);
+		cluster = MPIDR_AFFINITY_LEVEL(cpu_logical_map(i), 1);
+		if (cluster >= 2) {
+			pr_err("%s: only dual cluster systems are supported\n", __func__);
+			return -EINVAL;
+		}
+		if (WARN_ON(cpu >= MAX_CPUS_PER_CLUSTER))
+			return -EINVAL;
+		mask |= (1 << cluster);
+	}
+	if (mask != 3) {
+		pr_err("%s: no CPU pairing possible\n", __func__);
+		return -EINVAL;
+	}
+
+	/*
+	 * Now let's do the pairing.  We match each CPU with another CPU
+	 * from a different cluster.  To get a uniform scheduling behavior
+	 * without fiddling with CPU topology and compute capacity data,
+	 * we'll use logical CPUs initially belonging to the same cluster.
+	 */
+	memset(bL_switcher_cpu_pairing, -1, sizeof(bL_switcher_cpu_pairing));
+	cpumask_copy(&available_cpus, cpu_online_mask);
+	cluster_0 = -1;
+	for_each_cpu(i, &available_cpus) {
+		int match = -1;
+		cluster = MPIDR_AFFINITY_LEVEL(cpu_logical_map(i), 1);
+		if (cluster_0 == -1)
+			cluster_0 = cluster;
+		if (cluster != cluster_0)
+			continue;
+		cpumask_clear_cpu(i, &available_cpus);
+		for_each_cpu(j, &available_cpus) {
+			cluster = MPIDR_AFFINITY_LEVEL(cpu_logical_map(j), 1);
+			/*
+			 * Let's remember the last match to create "odd"
+			 * pairings on purpose in order for other code not
+			 * to assume any relation between physical and
+			 * logical CPU numbers.
+			 */
+			if (cluster != cluster_0)
+				match = j;
+		}
+		if (match != -1) {
+			bL_switcher_cpu_pairing[i] = match;
+			cpumask_clear_cpu(match, &available_cpus);
+			pr_info("CPU%d paired with CPU%d\n", i, match);
+		}
+	}
+
+	/*
+	 * Now we disable the unwanted CPUs i.e. everything that has no
+	 * pairing information (that includes the pairing counterparts).
+	 */
+	cpumask_clear(&bL_switcher_removed_logical_cpus);
+	for_each_online_cpu(i) {
+		cpu = MPIDR_AFFINITY_LEVEL(cpu_logical_map(i), 0);
+		cluster = MPIDR_AFFINITY_LEVEL(cpu_logical_map(i), 1);
+
+		/* Let's take note of the GIC ID for this CPU */
+		gic_id = gic_get_cpu_id(i);
+		if (gic_id < 0) {
+			pr_err("%s: bad GIC ID for CPU %d\n", __func__, i);
+			bL_switcher_restore_cpus();
+			return -EINVAL;
+		}
+		bL_gic_id[cpu][cluster] = gic_id;
+		pr_info("GIC ID for CPU %u cluster %u is %u\n",
+			cpu, cluster, gic_id);
+
+		if (bL_switcher_cpu_pairing[i] != -1) {
+			bL_switcher_cpu_original_cluster[i] = cluster;
+			continue;
+		}
+
+		ret = device_offline(get_cpu_device(i));
+		if (ret) {
+			bL_switcher_restore_cpus();
+			return ret;
+		}
+		cpumask_set_cpu(i, &bL_switcher_removed_logical_cpus);
+	}
+
+	return 0;
+}
+
+/* Determine the logical CPU a given physical CPU is grouped on. */
+int bL_switcher_get_logical_index(u32 mpidr)
+{
+	int cpu;
+
+	if (!bL_switcher_active)
+		return -EUNATCH;
+
+	mpidr &= MPIDR_HWID_BITMASK;
+	for_each_online_cpu(cpu) {
+		int pairing = bL_switcher_cpu_pairing[cpu];
+		if (pairing == -1)
+			continue;
+		if ((mpidr == cpu_logical_map(cpu)) ||
+		    (mpidr == cpu_logical_map(pairing)))
+			return cpu;
+	}
+	return -EINVAL;
+}
+
+static void bL_switcher_trace_trigger_cpu(void *__always_unused info)
+{
+	trace_cpu_migrate_current(ktime_get_real_ns(), read_mpidr());
+}
+
+int bL_switcher_trace_trigger(void)
+{
+	int ret;
+
+	preempt_disable();
+
+	bL_switcher_trace_trigger_cpu(NULL);
+	ret = smp_call_function(bL_switcher_trace_trigger_cpu, NULL, true);
+
+	preempt_enable();
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(bL_switcher_trace_trigger);
+
+static int bL_switcher_enable(void)
+{
+	int cpu, ret;
+
+	mutex_lock(&bL_switcher_activation_lock);
+	lock_device_hotplug();
+	if (bL_switcher_active) {
+		unlock_device_hotplug();
+		mutex_unlock(&bL_switcher_activation_lock);
+		return 0;
+	}
+
+	pr_info("big.LITTLE switcher initializing\n");
+
+	ret = bL_activation_notify(BL_NOTIFY_PRE_ENABLE);
+	if (ret)
+		goto error;
+
+	ret = bL_switcher_halve_cpus();
+	if (ret)
+		goto error;
+
+	bL_switcher_trace_trigger();
+
+	for_each_online_cpu(cpu) {
+		struct bL_thread *t = &bL_threads[cpu];
+		spin_lock_init(&t->lock);
+		init_waitqueue_head(&t->wq);
+		init_completion(&t->started);
+		t->wanted_cluster = -1;
+		t->task = bL_switcher_thread_create(cpu, t);
+	}
+
+	bL_switcher_active = 1;
+	bL_activation_notify(BL_NOTIFY_POST_ENABLE);
+	pr_info("big.LITTLE switcher initialized\n");
+	goto out;
+
+error:
+	pr_warn("big.LITTLE switcher initialization failed\n");
+	bL_activation_notify(BL_NOTIFY_POST_DISABLE);
+
+out:
+	unlock_device_hotplug();
+	mutex_unlock(&bL_switcher_activation_lock);
+	return ret;
+}
+
+#ifdef CONFIG_SYSFS
+
+static void bL_switcher_disable(void)
+{
+	unsigned int cpu, cluster;
+	struct bL_thread *t;
+	struct task_struct *task;
+
+	mutex_lock(&bL_switcher_activation_lock);
+	lock_device_hotplug();
+
+	if (!bL_switcher_active)
+		goto out;
+
+	if (bL_activation_notify(BL_NOTIFY_PRE_DISABLE) != 0) {
+		bL_activation_notify(BL_NOTIFY_POST_ENABLE);
+		goto out;
+	}
+
+	bL_switcher_active = 0;
+
+	/*
+	 * To deactivate the switcher, we must shut down the switcher
+	 * threads to prevent any other requests from being accepted.
+	 * Then, if the final cluster for given logical CPU is not the
+	 * same as the original one, we'll recreate a switcher thread
+	 * just for the purpose of switching the CPU back without any
+	 * possibility for interference from external requests.
+	 */
+	for_each_online_cpu(cpu) {
+		t = &bL_threads[cpu];
+		task = t->task;
+		t->task = NULL;
+		if (!task || IS_ERR(task))
+			continue;
+		kthread_stop(task);
+		/* no more switch may happen on this CPU at this point */
+		cluster = MPIDR_AFFINITY_LEVEL(cpu_logical_map(cpu), 1);
+		if (cluster == bL_switcher_cpu_original_cluster[cpu])
+			continue;
+		init_completion(&t->started);
+		t->wanted_cluster = bL_switcher_cpu_original_cluster[cpu];
+		task = bL_switcher_thread_create(cpu, t);
+		if (!IS_ERR(task)) {
+			wait_for_completion(&t->started);
+			kthread_stop(task);
+			cluster = MPIDR_AFFINITY_LEVEL(cpu_logical_map(cpu), 1);
+			if (cluster == bL_switcher_cpu_original_cluster[cpu])
+				continue;
+		}
+		/* If execution gets here, we're in trouble. */
+		pr_crit("%s: unable to restore original cluster for CPU %d\n",
+			__func__, cpu);
+		pr_crit("%s: CPU %d can't be restored\n",
+			__func__, bL_switcher_cpu_pairing[cpu]);
+		cpumask_clear_cpu(bL_switcher_cpu_pairing[cpu],
+				  &bL_switcher_removed_logical_cpus);
+	}
+
+	bL_switcher_restore_cpus();
+	bL_switcher_trace_trigger();
+
+	bL_activation_notify(BL_NOTIFY_POST_DISABLE);
+
+out:
+	unlock_device_hotplug();
+	mutex_unlock(&bL_switcher_activation_lock);
+}
+
+static ssize_t bL_switcher_active_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%u\n", bL_switcher_active);
+}
+
+static ssize_t bL_switcher_active_store(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	int ret;
+
+	switch (buf[0]) {
+	case '0':
+		bL_switcher_disable();
+		ret = 0;
+		break;
+	case '1':
+		ret = bL_switcher_enable();
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return (ret >= 0) ? count : ret;
+}
+
+static ssize_t bL_switcher_trace_trigger_store(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	int ret = bL_switcher_trace_trigger();
+
+	return ret ? ret : count;
+}
+
+static struct kobj_attribute bL_switcher_active_attr =
+	__ATTR(active, 0644, bL_switcher_active_show, bL_switcher_active_store);
+
+static struct kobj_attribute bL_switcher_trace_trigger_attr =
+	__ATTR(trace_trigger, 0200, NULL, bL_switcher_trace_trigger_store);
+
+static struct attribute *bL_switcher_attrs[] = {
+	&bL_switcher_active_attr.attr,
+	&bL_switcher_trace_trigger_attr.attr,
+	NULL,
+};
+
+static struct attribute_group bL_switcher_attr_group = {
+	.attrs = bL_switcher_attrs,
+};
+
+static struct kobject *bL_switcher_kobj;
+
+static int __init bL_switcher_sysfs_init(void)
+{
+	int ret;
+
+	bL_switcher_kobj = kobject_create_and_add("bL_switcher", kernel_kobj);
+	if (!bL_switcher_kobj)
+		return -ENOMEM;
+	ret = sysfs_create_group(bL_switcher_kobj, &bL_switcher_attr_group);
+	if (ret)
+		kobject_put(bL_switcher_kobj);
+	return ret;
+}
+
+#endif  /* CONFIG_SYSFS */
+
+bool bL_switcher_get_enabled(void)
+{
+	mutex_lock(&bL_switcher_activation_lock);
+
+	return bL_switcher_active;
+}
+EXPORT_SYMBOL_GPL(bL_switcher_get_enabled);
+
+void bL_switcher_put_enabled(void)
+{
+	mutex_unlock(&bL_switcher_activation_lock);
+}
+EXPORT_SYMBOL_GPL(bL_switcher_put_enabled);
+
+/*
+ * Veto any CPU hotplug operation on those CPUs we've removed
+ * while the switcher is active.
+ * We're just not ready to deal with that given the trickery involved.
+ */
+static int bL_switcher_hotplug_callback(struct notifier_block *nfb,
+					unsigned long action, void *hcpu)
+{
+	if (bL_switcher_active) {
+		int pairing = bL_switcher_cpu_pairing[(unsigned long)hcpu];
+		switch (action & 0xf) {
+		case CPU_UP_PREPARE:
+		case CPU_DOWN_PREPARE:
+			if (pairing == -1)
+				return NOTIFY_BAD;
+		}
+	}
+	return NOTIFY_DONE;
+}
+
+static bool no_bL_switcher;
+core_param(no_bL_switcher, no_bL_switcher, bool, 0644);
+
+static int __init bL_switcher_init(void)
+{
+	int ret;
+
+	if (!mcpm_is_available())
+		return -ENODEV;
+
+	cpu_notifier(bL_switcher_hotplug_callback, 0);
+
+	if (!no_bL_switcher) {
+		ret = bL_switcher_enable();
+		if (ret)
+			return ret;
+	}
+
+#ifdef CONFIG_SYSFS
+	ret = bL_switcher_sysfs_init();
+	if (ret)
+		pr_err("%s: unable to create sysfs entry\n", __func__);
+#endif
+
+	return 0;
+}
+
+late_initcall(bL_switcher_init);

arch/arm/common/bL_switcher_dummy_if.c

@@ -0,0 +1,71 @@
+/*
+ * arch/arm/common/bL_switcher_dummy_if.c -- b.L switcher dummy interface
+ *
+ * Created by:	Nicolas Pitre, November 2012
+ * Copyright:	(C) 2012-2013  Linaro Limited
+ *
+ * Dummy interface to user space for debugging purpose only.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <asm/uaccess.h>
+#include <asm/bL_switcher.h>
+
+static ssize_t bL_switcher_write(struct file *file, const char __user *buf,
+			size_t len, loff_t *pos)
+{
+	unsigned char val[3];
+	unsigned int cpu, cluster;
+	int ret;
+
+	pr_debug("%s\n", __func__);
+
+	if (len < 3)
+		return -EINVAL;
+
+	if (copy_from_user(val, buf, 3))
+		return -EFAULT;
+
+	/* format: <cpu#>,<cluster#> */
+	if (val[0] < '0' || val[0] > '9' ||
+	    val[1] != ',' ||
+	    val[2] < '0' || val[2] > '1')
+		return -EINVAL;
+
+	cpu = val[0] - '0';
+	cluster = val[2] - '0';
+	ret = bL_switch_request(cpu, cluster);
+
+	return ret ? : len;
+}
+
+static const struct file_operations bL_switcher_fops = {
+	.write		= bL_switcher_write,
+	.owner	= THIS_MODULE,
+};
+
+static struct miscdevice bL_switcher_device = {
+	MISC_DYNAMIC_MINOR,
+	"b.L_switcher",
+	&bL_switcher_fops
+};
+
+static int __init bL_switcher_dummy_if_init(void)
+{
+	return misc_register(&bL_switcher_device);
+}
+
+static void __exit bL_switcher_dummy_if_exit(void)
+{
+	misc_deregister(&bL_switcher_device);
+}
+
+module_init(bL_switcher_dummy_if_init);
+module_exit(bL_switcher_dummy_if_exit);

arch/arm/common/dmabounce.c

@@ -0,0 +1,579 @@
+/*
+ *  arch/arm/common/dmabounce.c
+ *
+ *  Special dma_{map/unmap/dma_sync}_* routines for systems that have
+ *  limited DMA windows. These functions utilize bounce buffers to
+ *  copy data to/from buffers located outside the DMA region. This
+ *  only works for systems in which DMA memory is at the bottom of
+ *  RAM, the remainder of memory is at the top and the DMA memory
+ *  can be marked as ZONE_DMA. Anything beyond that such as discontiguous
+ *  DMA windows will require custom implementations that reserve memory
+ *  areas at early bootup.
+ *
+ *  Original version by Brad Parker (brad@heeltoe.com)
+ *  Re-written by Christopher Hoover <ch@murgatroid.com>
+ *  Made generic by Deepak Saxena <dsaxena@plexity.net>
+ *
+ *  Copyright (C) 2002 Hewlett Packard Company.
+ *  Copyright (C) 2004 MontaVista Software, Inc.
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  version 2 as published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/page-flags.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
+#include <linux/list.h>
+#include <linux/scatterlist.h>
+
+#include <asm/cacheflush.h>
+
+#undef STATS
+
+#ifdef STATS
+#define DO_STATS(X) do { X ; } while (0)
+#else
+#define DO_STATS(X) do { } while (0)
+#endif
+
+/* ************************************************** */
+
+struct safe_buffer {
+	struct list_head node;
+
+	/* original request */
+	void		*ptr;
+	size_t		size;
+	int		direction;
+
+	/* safe buffer info */
+	struct dmabounce_pool *pool;
+	void		*safe;
+	dma_addr_t	safe_dma_addr;
+};
+
+struct dmabounce_pool {
+	unsigned long	size;
+	struct dma_pool	*pool;
+#ifdef STATS
+	unsigned long	allocs;
+#endif
+};
+
+struct dmabounce_device_info {
+	struct device *dev;
+	struct list_head safe_buffers;
+#ifdef STATS
+	unsigned long total_allocs;
+	unsigned long map_op_count;
+	unsigned long bounce_count;
+	int attr_res;
+#endif
+	struct dmabounce_pool	small;
+	struct dmabounce_pool	large;
+
+	rwlock_t lock;
+
+	int (*needs_bounce)(struct device *, dma_addr_t, size_t);
+};
+
+#ifdef STATS
+static ssize_t dmabounce_show(struct device *dev, struct device_attribute *attr,
+			      char *buf)
+{
+	struct dmabounce_device_info *device_info = dev->archdata.dmabounce;
+	return sprintf(buf, "%lu %lu %lu %lu %lu %lu\n",
+		device_info->small.allocs,
+		device_info->large.allocs,
+		device_info->total_allocs - device_info->small.allocs -
+			device_info->large.allocs,
+		device_info->total_allocs,
+		device_info->map_op_count,
+		device_info->bounce_count);
+}
+
+static DEVICE_ATTR(dmabounce_stats, 0400, dmabounce_show, NULL);
+#endif
+
+
+/* allocate a 'safe' buffer and keep track of it */
+static inline struct safe_buffer *
+alloc_safe_buffer(struct dmabounce_device_info *device_info, void *ptr,
+		  size_t size, enum dma_data_direction dir)
+{
+	struct safe_buffer *buf;
+	struct dmabounce_pool *pool;
+	struct device *dev = device_info->dev;
+	unsigned long flags;
+
+	dev_dbg(dev, "%s(ptr=%p, size=%d, dir=%d)\n",
+		__func__, ptr, size, dir);
+
+	if (size <= device_info->small.size) {
+		pool = &device_info->small;
+	} else if (size <= device_info->large.size) {
+		pool = &device_info->large;
+	} else {
+		pool = NULL;
+	}
+
+	buf = kmalloc(sizeof(struct safe_buffer), GFP_ATOMIC);
+	if (buf == NULL) {
+		dev_warn(dev, "%s: kmalloc failed\n", __func__);
+		return NULL;
+	}
+
+	buf->ptr = ptr;
+	buf->size = size;
+	buf->direction = dir;
+	buf->pool = pool;
+
+	if (pool) {
+		buf->safe = dma_pool_alloc(pool->pool, GFP_ATOMIC,
+					   &buf->safe_dma_addr);
+	} else {
+		buf->safe = dma_alloc_coherent(dev, size, &buf->safe_dma_addr,
+					       GFP_ATOMIC);
+	}
+
+	if (buf->safe == NULL) {
+		dev_warn(dev,
+			 "%s: could not alloc dma memory (size=%d)\n",
+			 __func__, size);
+		kfree(buf);
+		return NULL;
+	}
+
+#ifdef STATS
+	if (pool)
+		pool->allocs++;
+	device_info->total_allocs++;
+#endif
+
+	write_lock_irqsave(&device_info->lock, flags);
+	list_add(&buf->node, &device_info->safe_buffers);
+	write_unlock_irqrestore(&device_info->lock, flags);
+
+	return buf;
+}
+
+/* determine if a buffer is from our "safe" pool */
+static inline struct safe_buffer *
+find_safe_buffer(struct dmabounce_device_info *device_info, dma_addr_t safe_dma_addr)
+{
+	struct safe_buffer *b, *rb = NULL;
+	unsigned long flags;
+
+	read_lock_irqsave(&device_info->lock, flags);
+
+	list_for_each_entry(b, &device_info->safe_buffers, node)
+		if (b->safe_dma_addr <= safe_dma_addr &&
+		    b->safe_dma_addr + b->size > safe_dma_addr) {
+			rb = b;
+			break;
+		}
+
+	read_unlock_irqrestore(&device_info->lock, flags);
+	return rb;
+}
+
+static inline void
+free_safe_buffer(struct dmabounce_device_info *device_info, struct safe_buffer *buf)
+{
+	unsigned long flags;
+
+	dev_dbg(device_info->dev, "%s(buf=%p)\n", __func__, buf);
+
+	write_lock_irqsave(&device_info->lock, flags);
+
+	list_del(&buf->node);
+
+	write_unlock_irqrestore(&device_info->lock, flags);
+
+	if (buf->pool)
+		dma_pool_free(buf->pool->pool, buf->safe, buf->safe_dma_addr);
+	else
+		dma_free_coherent(device_info->dev, buf->size, buf->safe,
+				    buf->safe_dma_addr);
+
+	kfree(buf);
+}
+
+/* ************************************************** */
+
+static struct safe_buffer *find_safe_buffer_dev(struct device *dev,
+		dma_addr_t dma_addr, const char *where)
+{
+	if (!dev || !dev->archdata.dmabounce)
+		return NULL;
+	if (dma_mapping_error(dev, dma_addr)) {
+		dev_err(dev, "Trying to %s invalid mapping\n", where);
+		return NULL;
+	}
+	return find_safe_buffer(dev->archdata.dmabounce, dma_addr);
+}
+
+static int needs_bounce(struct device *dev, dma_addr_t dma_addr, size_t size)
+{
+	if (!dev || !dev->archdata.dmabounce)
+		return 0;
+
+	if (dev->dma_mask) {
+		unsigned long limit, mask = *dev->dma_mask;
+
+		limit = (mask + 1) & ~mask;
+		if (limit && size > limit) {
+			dev_err(dev, "DMA mapping too big (requested %#x "
+				"mask %#Lx)\n", size, *dev->dma_mask);
+			return -E2BIG;
+		}
+
+		/* Figure out if we need to bounce from the DMA mask. */
+		if ((dma_addr | (dma_addr + size - 1)) & ~mask)
+			return 1;
+	}
+
+	return !!dev->archdata.dmabounce->needs_bounce(dev, dma_addr, size);
+}
+
+static inline dma_addr_t map_single(struct device *dev, void *ptr, size_t size,
+		enum dma_data_direction dir)
+{
+	struct dmabounce_device_info *device_info = dev->archdata.dmabounce;
+	struct safe_buffer *buf;
+
+	if (device_info)
+		DO_STATS ( device_info->map_op_count++ );
+
+	buf = alloc_safe_buffer(device_info, ptr, size, dir);
+	if (buf == NULL) {
+		dev_err(dev, "%s: unable to map unsafe buffer %p!\n",
+		       __func__, ptr);
+		return DMA_ERROR_CODE;
+	}
+
+	dev_dbg(dev, "%s: unsafe buffer %p (dma=%#x) mapped to %p (dma=%#x)\n",
+		__func__, buf->ptr, virt_to_dma(dev, buf->ptr),
+		buf->safe, buf->safe_dma_addr);
+
+	if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL) {
+		dev_dbg(dev, "%s: copy unsafe %p to safe %p, size %d\n",
+			__func__, ptr, buf->safe, size);
+		memcpy(buf->safe, ptr, size);
+	}
+
+	return buf->safe_dma_addr;
+}
+
+static inline void unmap_single(struct device *dev, struct safe_buffer *buf,
+		size_t size, enum dma_data_direction dir)
+{
+	BUG_ON(buf->size != size);
+	BUG_ON(buf->direction != dir);
+
+	dev_dbg(dev, "%s: unsafe buffer %p (dma=%#x) mapped to %p (dma=%#x)\n",
+		__func__, buf->ptr, virt_to_dma(dev, buf->ptr),
+		buf->safe, buf->safe_dma_addr);
+
+	DO_STATS(dev->archdata.dmabounce->bounce_count++);
+
+	if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL) {
+		void *ptr = buf->ptr;
+
+		dev_dbg(dev, "%s: copy back safe %p to unsafe %p size %d\n",
+			__func__, buf->safe, ptr, size);
+		memcpy(ptr, buf->safe, size);
+
+		/*
+		 * Since we may have written to a page cache page,
+		 * we need to ensure that the data will be coherent
+		 * with user mappings.
+		 */
+		__cpuc_flush_dcache_area(ptr, size);
+	}
+	free_safe_buffer(dev->archdata.dmabounce, buf);
+}
+
+/* ************************************************** */
+
+/*
+ * see if a buffer address is in an 'unsafe' range.  if it is
+ * allocate a 'safe' buffer and copy the unsafe buffer into it.
+ * substitute the safe buffer for the unsafe one.
+ * (basically move the buffer from an unsafe area to a safe one)
+ */
+static dma_addr_t dmabounce_map_page(struct device *dev, struct page *page,
+		unsigned long offset, size_t size, enum dma_data_direction dir,
+		struct dma_attrs *attrs)
+{
+	dma_addr_t dma_addr;
+	int ret;
+
+	dev_dbg(dev, "%s(page=%p,off=%#lx,size=%zx,dir=%x)\n",
+		__func__, page, offset, size, dir);
+
+	dma_addr = pfn_to_dma(dev, page_to_pfn(page)) + offset;
+
+	ret = needs_bounce(dev, dma_addr, size);
+	if (ret < 0)
+		return DMA_ERROR_CODE;
+
+	if (ret == 0) {
+		arm_dma_ops.sync_single_for_device(dev, dma_addr, size, dir);
+		return dma_addr;
+	}
+
+	if (PageHighMem(page)) {
+		dev_err(dev, "DMA buffer bouncing of HIGHMEM pages is not supported\n");
+		return DMA_ERROR_CODE;
+	}
+
+	return map_single(dev, page_address(page) + offset, size, dir);
+}
+
+/*
+ * see if a mapped address was really a "safe" buffer and if so, copy
+ * the data from the safe buffer back to the unsafe buffer and free up
+ * the safe buffer.  (basically return things back to the way they
+ * should be)
+ */
+static void dmabounce_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
+		enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+	struct safe_buffer *buf;
+
+	dev_dbg(dev, "%s(dma=%#x,size=%d,dir=%x)\n",
+		__func__, dma_addr, size, dir);
+
+	buf = find_safe_buffer_dev(dev, dma_addr, __func__);
+	if (!buf) {
+		arm_dma_ops.sync_single_for_cpu(dev, dma_addr, size, dir);
+		return;
+	}
+
+	unmap_single(dev, buf, size, dir);
+}
+
+static int __dmabounce_sync_for_cpu(struct device *dev, dma_addr_t addr,
+		size_t sz, enum dma_data_direction dir)
+{
+	struct safe_buffer *buf;
+	unsigned long off;
+
+	dev_dbg(dev, "%s(dma=%#x,sz=%zx,dir=%x)\n",
+		__func__, addr, sz, dir);
+
+	buf = find_safe_buffer_dev(dev, addr, __func__);
+	if (!buf)
+		return 1;
+
+	off = addr - buf->safe_dma_addr;
+
+	BUG_ON(buf->direction != dir);
+
+	dev_dbg(dev, "%s: unsafe buffer %p (dma=%#x off=%#lx) mapped to %p (dma=%#x)\n",
+		__func__, buf->ptr, virt_to_dma(dev, buf->ptr), off,
+		buf->safe, buf->safe_dma_addr);
+
+	DO_STATS(dev->archdata.dmabounce->bounce_count++);
+
+	if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL) {
+		dev_dbg(dev, "%s: copy back safe %p to unsafe %p size %d\n",
+			__func__, buf->safe + off, buf->ptr + off, sz);
+		memcpy(buf->ptr + off, buf->safe + off, sz);
+	}
+	return 0;
+}
+
+static void dmabounce_sync_for_cpu(struct device *dev,
+		dma_addr_t handle, size_t size, enum dma_data_direction dir)
+{
+	if (!__dmabounce_sync_for_cpu(dev, handle, size, dir))
+		return;
+
+	arm_dma_ops.sync_single_for_cpu(dev, handle, size, dir);
+}
+
+static int __dmabounce_sync_for_device(struct device *dev, dma_addr_t addr,
+		size_t sz, enum dma_data_direction dir)
+{
+	struct safe_buffer *buf;
+	unsigned long off;
+
+	dev_dbg(dev, "%s(dma=%#x,sz=%zx,dir=%x)\n",
+		__func__, addr, sz, dir);
+
+	buf = find_safe_buffer_dev(dev, addr, __func__);
+	if (!buf)
+		return 1;
+
+	off = addr - buf->safe_dma_addr;
+
+	BUG_ON(buf->direction != dir);
+
+	dev_dbg(dev, "%s: unsafe buffer %p (dma=%#x off=%#lx) mapped to %p (dma=%#x)\n",
+		__func__, buf->ptr, virt_to_dma(dev, buf->ptr), off,
+		buf->safe, buf->safe_dma_addr);
+
+	DO_STATS(dev->archdata.dmabounce->bounce_count++);
+
+	if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL) {
+		dev_dbg(dev, "%s: copy out unsafe %p to safe %p, size %d\n",
+			__func__,buf->ptr + off, buf->safe + off, sz);
+		memcpy(buf->safe + off, buf->ptr + off, sz);
+	}
+	return 0;
+}
+
+static void dmabounce_sync_for_device(struct device *dev,
+		dma_addr_t handle, size_t size, enum dma_data_direction dir)
+{
+	if (!__dmabounce_sync_for_device(dev, handle, size, dir))
+		return;
+
+	arm_dma_ops.sync_single_for_device(dev, handle, size, dir);
+}
+
+static int dmabounce_set_mask(struct device *dev, u64 dma_mask)
+{
+	if (dev->archdata.dmabounce)
+		return 0;
+
+	return arm_dma_ops.set_dma_mask(dev, dma_mask);
+}
+
+static struct dma_map_ops dmabounce_ops = {
+	.alloc			= arm_dma_alloc,
+	.free			= arm_dma_free,
+	.mmap			= arm_dma_mmap,
+	.get_sgtable		= arm_dma_get_sgtable,
+	.map_page		= dmabounce_map_page,
+	.unmap_page		= dmabounce_unmap_page,
+	.sync_single_for_cpu	= dmabounce_sync_for_cpu,
+	.sync_single_for_device	= dmabounce_sync_for_device,
+	.map_sg			= arm_dma_map_sg,
+	.unmap_sg		= arm_dma_unmap_sg,
+	.sync_sg_for_cpu	= arm_dma_sync_sg_for_cpu,
+	.sync_sg_for_device	= arm_dma_sync_sg_for_device,
+	.set_dma_mask		= dmabounce_set_mask,
+};
+
+static int dmabounce_init_pool(struct dmabounce_pool *pool, struct device *dev,
+		const char *name, unsigned long size)
+{
+	pool->size = size;
+	DO_STATS(pool->allocs = 0);
+	pool->pool = dma_pool_create(name, dev, size,
+				     0 /* byte alignment */,
+				     0 /* no page-crossing issues */);
+
+	return pool->pool ? 0 : -ENOMEM;
+}
+
+int dmabounce_register_dev(struct device *dev, unsigned long small_buffer_size,
+		unsigned long large_buffer_size,
+		int (*needs_bounce_fn)(struct device *, dma_addr_t, size_t))
+{
+	struct dmabounce_device_info *device_info;
+	int ret;
+
+	device_info = kmalloc(sizeof(struct dmabounce_device_info), GFP_ATOMIC);
+	if (!device_info) {
+		dev_err(dev,
+			"Could not allocated dmabounce_device_info\n");
+		return -ENOMEM;
+	}
+
+	ret = dmabounce_init_pool(&device_info->small, dev,
+				  "small_dmabounce_pool", small_buffer_size);
+	if (ret) {
+		dev_err(dev,
+			"dmabounce: could not allocate DMA pool for %ld byte objects\n",
+			small_buffer_size);
+		goto err_free;
+	}
+
+	if (large_buffer_size) {
+		ret = dmabounce_init_pool(&device_info->large, dev,
+					  "large_dmabounce_pool",
+					  large_buffer_size);
+		if (ret) {
+			dev_err(dev,
+				"dmabounce: could not allocate DMA pool for %ld byte objects\n",
+				large_buffer_size);
+			goto err_destroy;
+		}
+	}
+
+	device_info->dev = dev;
+	INIT_LIST_HEAD(&device_info->safe_buffers);
+	rwlock_init(&device_info->lock);
+	device_info->needs_bounce = needs_bounce_fn;
+
+#ifdef STATS
+	device_info->total_allocs = 0;
+	device_info->map_op_count = 0;
+	device_info->bounce_count = 0;
+	device_info->attr_res = device_create_file(dev, &dev_attr_dmabounce_stats);
+#endif
+
+	dev->archdata.dmabounce = device_info;
+	set_dma_ops(dev, &dmabounce_ops);
+
+	dev_info(dev, "dmabounce: registered device\n");
+
+	return 0;
+
+ err_destroy:
+	dma_pool_destroy(device_info->small.pool);
+ err_free:
+	kfree(device_info);
+	return ret;
+}
+EXPORT_SYMBOL(dmabounce_register_dev);
+
+void dmabounce_unregister_dev(struct device *dev)
+{
+	struct dmabounce_device_info *device_info = dev->archdata.dmabounce;
+
+	dev->archdata.dmabounce = NULL;
+	set_dma_ops(dev, NULL);
+
+	if (!device_info) {
+		dev_warn(dev,
+			 "Never registered with dmabounce but attempting"
+			 "to unregister!\n");
+		return;
+	}
+
+	if (!list_empty(&device_info->safe_buffers)) {
+		dev_err(dev,
+			"Removing from dmabounce with pending buffers!\n");
+		BUG();
+	}
+
+	if (device_info->small.pool)
+		dma_pool_destroy(device_info->small.pool);
+	if (device_info->large.pool)
+		dma_pool_destroy(device_info->large.pool);
+
+#ifdef STATS
+	if (device_info->attr_res == 0)
+		device_remove_file(dev, &dev_attr_dmabounce_stats);
+#endif
+
+	kfree(device_info);
+
+	dev_info(dev, "dmabounce: device unregistered\n");
+}
+EXPORT_SYMBOL(dmabounce_unregister_dev);
+
+MODULE_AUTHOR("Christopher Hoover <ch@hpl.hp.com>, Deepak Saxena <dsaxena@plexity.net>");
+MODULE_DESCRIPTION("Special dma_{map/unmap/dma_sync}_* routines for systems with limited DMA windows");
+MODULE_LICENSE("GPL");

arch/arm/common/fiq_glue.S

@@ -0,0 +1,118 @@
+/*
+ * Copyright (C) 2008 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+		.text
+
+		.global fiq_glue_end
+
+		/* fiq stack: r0-r15,cpsr,spsr of interrupted mode */
+
+ENTRY(fiq_glue)
+		/* store pc, cpsr from previous mode, reserve space for spsr */
+		mrs	r12, spsr
+		sub	lr, lr, #4
+		subs	r10, #1
+		bne	nested_fiq
+
+		str	r12, [sp, #-8]!
+		str	lr, [sp, #-4]!
+
+		/* store r8-r14 from previous mode */
+		sub	sp, sp, #(7 * 4)
+		stmia	sp, {r8-r14}^
+		nop
+
+		/* store r0-r7 from previous mode */
+		stmfd	sp!, {r0-r7}
+
+		/* setup func(data,regs) arguments */
+		mov	r0, r9
+		mov	r1, sp
+		mov	r3, r8
+
+		mov	r7, sp
+
+		/* Get sp and lr from non-user modes */
+		and	r4, r12, #MODE_MASK
+		cmp	r4, #USR_MODE
+		beq	fiq_from_usr_mode
+
+		mov	r7, sp
+		orr	r4, r4, #(PSR_I_BIT | PSR_F_BIT)
+		msr	cpsr_c, r4
+		str	sp, [r7, #(4 * 13)]
+		str	lr, [r7, #(4 * 14)]
+		mrs	r5, spsr
+		str	r5, [r7, #(4 * 17)]
+
+		cmp	r4, #(SVC_MODE | PSR_I_BIT | PSR_F_BIT)
+		/* use fiq stack if we reenter this mode */
+		subne	sp, r7, #(4 * 3)
+
+fiq_from_usr_mode:
+		msr	cpsr_c, #(SVC_MODE | PSR_I_BIT | PSR_F_BIT)
+		mov	r2, sp
+		sub	sp, r7, #12
+		stmfd	sp!, {r2, ip, lr}
+		/* call func(data,regs) */
+		blx	r3
+		ldmfd	sp, {r2, ip, lr}
+		mov	sp, r2
+
+		/* restore/discard saved state */
+		cmp	r4, #USR_MODE
+		beq	fiq_from_usr_mode_exit
+
+		msr	cpsr_c, r4
+		ldr	sp, [r7, #(4 * 13)]
+		ldr	lr, [r7, #(4 * 14)]
+		msr	spsr_cxsf, r5
+
+fiq_from_usr_mode_exit:
+		msr	cpsr_c, #(FIQ_MODE | PSR_I_BIT | PSR_F_BIT)
+
+		ldmfd	sp!, {r0-r7}
+		ldr	lr, [sp, #(4 * 7)]
+		ldr	r12, [sp, #(4 * 8)]
+		add	sp, sp, #(10 * 4)
+exit_fiq:
+		msr	spsr_cxsf, r12
+		add	r10, #1
+		cmp	r11, #0
+		moveqs	pc, lr
+		bx	r11 /* jump to custom fiq return function */
+
+nested_fiq:
+		orr	r12, r12, #(PSR_F_BIT)
+		b	exit_fiq
+
+fiq_glue_end:
+
+ENTRY(fiq_glue_setup) /* func, data, sp, smc call number */
+		stmfd		sp!, {r4}
+		mrs		r4, cpsr
+		msr		cpsr_c, #(FIQ_MODE | PSR_I_BIT | PSR_F_BIT)
+		movs		r8, r0
+		mov		r9, r1
+		mov		sp, r2
+		mov		r11, r3
+		moveq		r10, #0
+		movne		r10, #1
+		msr		cpsr_c, r4
+		ldmfd		sp!, {r4}
+		bx		lr
+

arch/arm/common/fiq_glue_setup.c

@@ -0,0 +1,147 @@
+/*
+ * Copyright (C) 2010 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/percpu.h>
+#include <linux/slab.h>
+#include <asm/fiq.h>
+#include <asm/fiq_glue.h>
+
+extern unsigned char fiq_glue, fiq_glue_end;
+extern void fiq_glue_setup(void *func, void *data, void *sp,
+			   fiq_return_handler_t fiq_return_handler);
+
+static struct fiq_handler fiq_debbuger_fiq_handler = {
+	.name = "fiq_glue",
+};
+DEFINE_PER_CPU(void *, fiq_stack);
+static struct fiq_glue_handler *current_handler;
+static fiq_return_handler_t fiq_return_handler;
+static DEFINE_MUTEX(fiq_glue_lock);
+
+static void fiq_glue_setup_helper(void *info)
+{
+	struct fiq_glue_handler *handler = info;
+	fiq_glue_setup(handler->fiq, handler,
+		__get_cpu_var(fiq_stack) + THREAD_START_SP,
+		fiq_return_handler);
+}
+
+int fiq_glue_register_handler(struct fiq_glue_handler *handler)
+{
+	int ret;
+	int cpu;
+
+	if (!handler || !handler->fiq)
+		return -EINVAL;
+
+	mutex_lock(&fiq_glue_lock);
+	if (fiq_stack) {
+		ret = -EBUSY;
+		goto err_busy;
+	}
+
+	for_each_possible_cpu(cpu) {
+		void *stack;
+		stack = (void *)__get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
+		if (WARN_ON(!stack)) {
+			ret = -ENOMEM;
+			goto err_alloc_fiq_stack;
+		}
+		per_cpu(fiq_stack, cpu) = stack;
+	}
+
+	ret = claim_fiq(&fiq_debbuger_fiq_handler);
+	if (WARN_ON(ret))
+		goto err_claim_fiq;
+
+	current_handler = handler;
+	on_each_cpu(fiq_glue_setup_helper, handler, true);
+	set_fiq_handler(&fiq_glue, &fiq_glue_end - &fiq_glue);
+
+	mutex_unlock(&fiq_glue_lock);
+	return 0;
+
+err_claim_fiq:
+err_alloc_fiq_stack:
+	for_each_possible_cpu(cpu) {
+		__free_pages(per_cpu(fiq_stack, cpu), THREAD_SIZE_ORDER);
+		per_cpu(fiq_stack, cpu) = NULL;
+	}
+err_busy:
+	mutex_unlock(&fiq_glue_lock);
+	return ret;
+}
+
+static void fiq_glue_update_return_handler(void (*fiq_return)(void))
+{
+	fiq_return_handler = fiq_return;
+	if (current_handler)
+		on_each_cpu(fiq_glue_setup_helper, current_handler, true);
+}
+
+int fiq_glue_set_return_handler(void (*fiq_return)(void))
+{
+	int ret;
+
+	mutex_lock(&fiq_glue_lock);
+	if (fiq_return_handler) {
+		ret = -EBUSY;
+		goto err_busy;
+	}
+	fiq_glue_update_return_handler(fiq_return);
+	ret = 0;
+err_busy:
+	mutex_unlock(&fiq_glue_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL(fiq_glue_set_return_handler);
+
+int fiq_glue_clear_return_handler(void (*fiq_return)(void))
+{
+	int ret;
+
+	mutex_lock(&fiq_glue_lock);
+	if (WARN_ON(fiq_return_handler != fiq_return)) {
+		ret = -EINVAL;
+		goto err_inval;
+	}
+	fiq_glue_update_return_handler(NULL);
+	ret = 0;
+err_inval:
+	mutex_unlock(&fiq_glue_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL(fiq_glue_clear_return_handler);
+
+/**
+ * fiq_glue_resume - Restore fiqs after suspend or low power idle states
+ *
+ * This must be called before calling local_fiq_enable after returning from a
+ * power state where the fiq mode registers were lost. If a driver provided
+ * a resume hook when it registered the handler it will be called.
+ */
+
+void fiq_glue_resume(void)
+{
+	if (!current_handler)
+		return;
+	fiq_glue_setup(current_handler->fiq, current_handler,
+		__get_cpu_var(fiq_stack) + THREAD_START_SP,
+		fiq_return_handler);
+	if (current_handler->resume)
+		current_handler->resume(current_handler);
+}
+

arch/arm/common/firmware.c

@@ -0,0 +1,18 @@
+/*
+ * Copyright (C) 2012 Samsung Electronics.
+ * Kyungmin Park <kyungmin.park@samsung.com>
+ * Tomasz Figa <t.figa@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/suspend.h>
+
+#include <asm/firmware.h>
+
+static const struct firmware_ops default_firmware_ops;
+
+const struct firmware_ops *firmware_ops = &default_firmware_ops;

arch/arm/common/icst.c

@@ -0,0 +1,100 @@
+/*
+ *  linux/arch/arm/common/icst307.c
+ *
+ *  Copyright (C) 2003 Deep Blue Solutions, Ltd, All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  Support functions for calculating clocks/divisors for the ICST307
+ *  clock generators.  See http://www.idt.com/ for more information
+ *  on these devices.
+ *
+ *  This is an almost identical implementation to the ICST525 clock generator.
+ *  The s2div and idx2s files are different
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+
+#include <asm/hardware/icst.h>
+
+/*
+ * Divisors for each OD setting.
+ */
+const unsigned char icst307_s2div[8] = { 10, 2, 8, 4, 5, 7, 3, 6 };
+const unsigned char icst525_s2div[8] = { 10, 2, 8, 4, 5, 7, 9, 6 };
+EXPORT_SYMBOL(icst307_s2div);
+EXPORT_SYMBOL(icst525_s2div);
+
+unsigned long icst_hz(const struct icst_params *p, struct icst_vco vco)
+{
+	return p->ref * 2 * (vco.v + 8) / ((vco.r + 2) * p->s2div[vco.s]);
+}
+
+EXPORT_SYMBOL(icst_hz);
+
+/*
+ * Ascending divisor S values.
+ */
+const unsigned char icst307_idx2s[8] = { 1, 6, 3, 4, 7, 5, 2, 0 };
+const unsigned char icst525_idx2s[8] = { 1, 3, 4, 7, 5, 2, 6, 0 };
+EXPORT_SYMBOL(icst307_idx2s);
+EXPORT_SYMBOL(icst525_idx2s);
+
+struct icst_vco
+icst_hz_to_vco(const struct icst_params *p, unsigned long freq)
+{
+	struct icst_vco vco = { .s = 1, .v = p->vd_max, .r = p->rd_max };
+	unsigned long f;
+	unsigned int i = 0, rd, best = (unsigned int)-1;
+
+	/*
+	 * First, find the PLL output divisor such
+	 * that the PLL output is within spec.
+	 */
+	do {
+		f = freq * p->s2div[p->idx2s[i]];
+
+		if (f > p->vco_min && f <= p->vco_max)
+			break;
+	} while (i < 8);
+
+	if (i >= 8)
+		return vco;
+
+	vco.s = p->idx2s[i];
+
+	/*
+	 * Now find the closest divisor combination
+	 * which gives a PLL output of 'f'.
+	 */
+	for (rd = p->rd_min; rd <= p->rd_max; rd++) {
+		unsigned long fref_div, f_pll;
+		unsigned int vd;
+		int f_diff;
+
+		fref_div = (2 * p->ref) / rd;
+
+		vd = (f + fref_div / 2) / fref_div;
+		if (vd < p->vd_min || vd > p->vd_max)
+			continue;
+
+		f_pll = fref_div * vd;
+		f_diff = f_pll - f;
+		if (f_diff < 0)
+			f_diff = -f_diff;
+
+		if ((unsigned)f_diff < best) {
+			vco.v = vd - 8;
+			vco.r = rd - 2;
+			if (f_diff == 0)
+				break;
+			best = f_diff;
+		}
+	}
+
+	return vco;
+}
+
+EXPORT_SYMBOL(icst_hz_to_vco);

arch/arm/common/it8152.c

@@ -0,0 +1,355 @@
+/*
+ * linux/arch/arm/common/it8152.c
+ *
+ * Copyright Compulab Ltd, 2002-2007
+ * Mike Rapoport <mike@compulab.co.il>
+ *
+ * The DMA bouncing part is taken from arch/arm/mach-ixp4xx/common-pci.c
+ * (see this file for respective copyrights)
+ *
+ * Thanks to Guennadi Liakhovetski <gl@dsa-ac.de> for IRQ enumberation
+ * and demux code.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/ptrace.h>
+#include <linux/interrupt.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/export.h>
+
+#include <asm/mach/pci.h>
+#include <asm/hardware/it8152.h>
+
+#define MAX_SLOTS		21
+
+static void it8152_mask_irq(struct irq_data *d)
+{
+	unsigned int irq = d->irq;
+
+       if (irq >= IT8152_LD_IRQ(0)) {
+	       __raw_writel((__raw_readl(IT8152_INTC_LDCNIMR) |
+			    (1 << (irq - IT8152_LD_IRQ(0)))),
+			    IT8152_INTC_LDCNIMR);
+       } else if (irq >= IT8152_LP_IRQ(0)) {
+	       __raw_writel((__raw_readl(IT8152_INTC_LPCNIMR) |
+			    (1 << (irq - IT8152_LP_IRQ(0)))),
+			    IT8152_INTC_LPCNIMR);
+       } else if (irq >= IT8152_PD_IRQ(0)) {
+	       __raw_writel((__raw_readl(IT8152_INTC_PDCNIMR) |
+			    (1 << (irq - IT8152_PD_IRQ(0)))),
+			    IT8152_INTC_PDCNIMR);
+       }
+}
+
+static void it8152_unmask_irq(struct irq_data *d)
+{
+	unsigned int irq = d->irq;
+
+       if (irq >= IT8152_LD_IRQ(0)) {
+	       __raw_writel((__raw_readl(IT8152_INTC_LDCNIMR) &
+			     ~(1 << (irq - IT8152_LD_IRQ(0)))),
+			    IT8152_INTC_LDCNIMR);
+       } else if (irq >= IT8152_LP_IRQ(0)) {
+	       __raw_writel((__raw_readl(IT8152_INTC_LPCNIMR) &
+			     ~(1 << (irq - IT8152_LP_IRQ(0)))),
+			    IT8152_INTC_LPCNIMR);
+       } else if (irq >= IT8152_PD_IRQ(0)) {
+	       __raw_writel((__raw_readl(IT8152_INTC_PDCNIMR) &
+			     ~(1 << (irq - IT8152_PD_IRQ(0)))),
+			    IT8152_INTC_PDCNIMR);
+       }
+}
+
+static struct irq_chip it8152_irq_chip = {
+	.name		= "it8152",
+	.irq_ack	= it8152_mask_irq,
+	.irq_mask	= it8152_mask_irq,
+	.irq_unmask	= it8152_unmask_irq,
+};
+
+void it8152_init_irq(void)
+{
+	int irq;
+
+	__raw_writel((0xffff), IT8152_INTC_PDCNIMR);
+	__raw_writel((0), IT8152_INTC_PDCNIRR);
+	__raw_writel((0xffff), IT8152_INTC_LPCNIMR);
+	__raw_writel((0), IT8152_INTC_LPCNIRR);
+	__raw_writel((0xffff), IT8152_INTC_LDCNIMR);
+	__raw_writel((0), IT8152_INTC_LDCNIRR);
+
+	for (irq = IT8152_IRQ(0); irq <= IT8152_LAST_IRQ; irq++) {
+		irq_set_chip_and_handler(irq, &it8152_irq_chip,
+					 handle_level_irq);
+		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+	}
+}
+
+void it8152_irq_demux(unsigned int irq, struct irq_desc *desc)
+{
+       int bits_pd, bits_lp, bits_ld;
+       int i;
+
+       while (1) {
+	       /* Read all */
+	       bits_pd = __raw_readl(IT8152_INTC_PDCNIRR);
+	       bits_lp = __raw_readl(IT8152_INTC_LPCNIRR);
+	       bits_ld = __raw_readl(IT8152_INTC_LDCNIRR);
+
+	       /* Ack */
+	       __raw_writel((~bits_pd), IT8152_INTC_PDCNIRR);
+	       __raw_writel((~bits_lp), IT8152_INTC_LPCNIRR);
+	       __raw_writel((~bits_ld), IT8152_INTC_LDCNIRR);
+
+	       if (!(bits_ld | bits_lp | bits_pd)) {
+		       /* Re-read to guarantee, that there was a moment of
+			  time, when they all three were 0. */
+		       bits_pd = __raw_readl(IT8152_INTC_PDCNIRR);
+		       bits_lp = __raw_readl(IT8152_INTC_LPCNIRR);
+		       bits_ld = __raw_readl(IT8152_INTC_LDCNIRR);
+		       if (!(bits_ld | bits_lp | bits_pd))
+			       return;
+	       }
+
+	       bits_pd &= ((1 << IT8152_PD_IRQ_COUNT) - 1);
+	       while (bits_pd) {
+		       i = __ffs(bits_pd);
+		       generic_handle_irq(IT8152_PD_IRQ(i));
+		       bits_pd &= ~(1 << i);
+	       }
+
+	       bits_lp &= ((1 << IT8152_LP_IRQ_COUNT) - 1);
+	       while (bits_lp) {
+		       i = __ffs(bits_lp);
+		       generic_handle_irq(IT8152_LP_IRQ(i));
+		       bits_lp &= ~(1 << i);
+	       }
+
+	       bits_ld &= ((1 << IT8152_LD_IRQ_COUNT) - 1);
+	       while (bits_ld) {
+		       i = __ffs(bits_ld);
+		       generic_handle_irq(IT8152_LD_IRQ(i));
+		       bits_ld &= ~(1 << i);
+	       }
+       }
+}
+
+/* mapping for on-chip devices */
+int __init it8152_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+	if ((dev->vendor == PCI_VENDOR_ID_ITE) &&
+	    (dev->device == PCI_DEVICE_ID_ITE_8152)) {
+		if ((dev->class >> 8) == PCI_CLASS_MULTIMEDIA_AUDIO)
+			return IT8152_AUDIO_INT;
+		if ((dev->class >> 8) == PCI_CLASS_SERIAL_USB)
+			return IT8152_USB_INT;
+		if ((dev->class >> 8) == PCI_CLASS_SYSTEM_DMA)
+			return IT8152_CDMA_INT;
+	}
+
+	return 0;
+}
+
+static unsigned long it8152_pci_dev_base_address(struct pci_bus *bus,
+						 unsigned int devfn)
+{
+	unsigned long addr = 0;
+
+	if (bus->number == 0) {
+			if (devfn < PCI_DEVFN(MAX_SLOTS, 0))
+				addr = (devfn << 8);
+	} else
+		addr = (bus->number << 16) | (devfn << 8);
+
+	return addr;
+}
+
+static int it8152_pci_read_config(struct pci_bus *bus,
+				  unsigned int devfn, int where,
+				  int size, u32 *value)
+{
+	unsigned long addr = it8152_pci_dev_base_address(bus, devfn);
+	u32 v;
+	int shift;
+
+	shift = (where & 3);
+
+	__raw_writel((addr + where), IT8152_PCI_CFG_ADDR);
+	v = (__raw_readl(IT8152_PCI_CFG_DATA)  >> (8 * (shift)));
+
+	*value = v;
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int it8152_pci_write_config(struct pci_bus *bus,
+				   unsigned int devfn, int where,
+				   int size, u32 value)
+{
+	unsigned long addr = it8152_pci_dev_base_address(bus, devfn);
+	u32 v, vtemp, mask = 0;
+	int shift;
+
+	if (size == 1)
+		mask = 0xff;
+	if (size == 2)
+		mask = 0xffff;
+
+	shift = (where & 3);
+
+	__raw_writel((addr + where), IT8152_PCI_CFG_ADDR);
+	vtemp = __raw_readl(IT8152_PCI_CFG_DATA);
+
+	if (mask)
+		vtemp &= ~(mask << (8 * shift));
+	else
+		vtemp = 0;
+
+	v = (value << (8 * shift));
+	__raw_writel((addr + where), IT8152_PCI_CFG_ADDR);
+	__raw_writel((v | vtemp), IT8152_PCI_CFG_DATA);
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+struct pci_ops it8152_ops = {
+	.read = it8152_pci_read_config,
+	.write = it8152_pci_write_config,
+};
+
+static struct resource it8152_io = {
+	.name	= "IT8152 PCI I/O region",
+	.flags	= IORESOURCE_IO,
+};
+
+static struct resource it8152_mem = {
+	.name	= "IT8152 PCI memory region",
+	.start	= 0x10000000,
+	.end	= 0x13e00000,
+	.flags	= IORESOURCE_MEM,
+};
+
+/*
+ * The following functions are needed for DMA bouncing.
+ * ITE8152 chip can address up to 64MByte, so all the devices
+ * connected to ITE8152 (PCI and USB) should have limited DMA window
+ */
+static int it8152_needs_bounce(struct device *dev, dma_addr_t dma_addr, size_t size)
+{
+	dev_dbg(dev, "%s: dma_addr %08x, size %08x\n",
+		__func__, dma_addr, size);
+	return (dma_addr + size - PHYS_OFFSET) >= SZ_64M;
+}
+
+/*
+ * Setup DMA mask to 64MB on devices connected to ITE8152. Ignore all
+ * other devices.
+ */
+static int it8152_pci_platform_notify(struct device *dev)
+{
+	if (dev_is_pci(dev)) {
+		if (dev->dma_mask)
+			*dev->dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
+		dev->coherent_dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
+		dmabounce_register_dev(dev, 2048, 4096, it8152_needs_bounce);
+	}
+	return 0;
+}
+
+static int it8152_pci_platform_notify_remove(struct device *dev)
+{
+	if (dev_is_pci(dev))
+		dmabounce_unregister_dev(dev);
+
+	return 0;
+}
+
+int dma_set_coherent_mask(struct device *dev, u64 mask)
+{
+	if (mask >= PHYS_OFFSET + SZ_64M - 1)
+		return 0;
+
+	return -EIO;
+}
+
+int __init it8152_pci_setup(int nr, struct pci_sys_data *sys)
+{
+	/*
+	 * FIXME: use pci_ioremap_io to remap the IO space here and
+	 * move over to the generic io.h implementation.
+	 * This requires solving the same problem for PXA PCMCIA
+	 * support.
+	 */
+	it8152_io.start = (unsigned long)IT8152_IO_BASE + 0x12000;
+	it8152_io.end	= (unsigned long)IT8152_IO_BASE + 0x12000 + 0x100000;
+
+	sys->mem_offset = 0x10000000;
+	sys->io_offset  = (unsigned long)IT8152_IO_BASE;
+
+	if (request_resource(&ioport_resource, &it8152_io)) {
+		printk(KERN_ERR "PCI: unable to allocate IO region\n");
+		goto err0;
+	}
+	if (request_resource(&iomem_resource, &it8152_mem)) {
+		printk(KERN_ERR "PCI: unable to allocate memory region\n");
+		goto err1;
+	}
+
+	pci_add_resource_offset(&sys->resources, &it8152_io, sys->io_offset);
+	pci_add_resource_offset(&sys->resources, &it8152_mem, sys->mem_offset);
+
+	if (platform_notify || platform_notify_remove) {
+		printk(KERN_ERR "PCI: Can't use platform_notify\n");
+		goto err2;
+	}
+
+	platform_notify = it8152_pci_platform_notify;
+	platform_notify_remove = it8152_pci_platform_notify_remove;
+
+	return 1;
+
+err2:
+	release_resource(&it8152_io);
+err1:
+	release_resource(&it8152_mem);
+err0:
+	return -EBUSY;
+}
+
+/* ITE bridge requires setting latency timer to avoid early bus access
+   termination by PCI bus master devices
+*/
+void pcibios_set_master(struct pci_dev *dev)
+{
+	u8 lat;
+
+	/* no need to update on-chip OHCI controller */
+	if ((dev->vendor == PCI_VENDOR_ID_ITE) &&
+	    (dev->device == PCI_DEVICE_ID_ITE_8152) &&
+	    ((dev->class >> 8) == PCI_CLASS_SERIAL_USB))
+		return;
+
+	pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
+	if (lat < 16)
+		lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
+	else if (lat > pcibios_max_latency)
+		lat = pcibios_max_latency;
+	else
+		return;
+	printk(KERN_DEBUG "PCI: Setting latency timer of device %s to %d\n",
+	       pci_name(dev), lat);
+	pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
+}
+
+
+EXPORT_SYMBOL(dma_set_coherent_mask);

arch/arm/common/locomo.c

@@ -0,0 +1,914 @@
+/*
+ * linux/arch/arm/common/locomo.c
+ *
+ * Sharp LoCoMo support
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This file contains all generic LoCoMo support.
+ *
+ * All initialization functions provided here are intended to be called
+ * from machine specific code with proper arguments when required.
+ *
+ * Based on sa1111.c
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/ioport.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/io.h>
+
+#include <mach/hardware.h>
+#include <asm/irq.h>
+#include <asm/mach/irq.h>
+
+#include <asm/hardware/locomo.h>
+
+/* LoCoMo Interrupts */
+#define IRQ_LOCOMO_KEY		(0)
+#define IRQ_LOCOMO_GPIO		(1)
+#define IRQ_LOCOMO_LT		(2)
+#define IRQ_LOCOMO_SPI		(3)
+
+/* M62332 output channel selection */
+#define M62332_EVR_CH	1	/* M62332 volume channel number  */
+				/*   0 : CH.1 , 1 : CH. 2        */
+/* DAC send data */
+#define	M62332_SLAVE_ADDR	0x4e	/* Slave address  */
+#define	M62332_W_BIT		0x00	/* W bit (0 only) */
+#define	M62332_SUB_ADDR		0x00	/* Sub address    */
+#define	M62332_A_BIT		0x00	/* A bit (0 only) */
+
+/* DAC setup and hold times (expressed in us) */
+#define DAC_BUS_FREE_TIME	5	/*   4.7 us */
+#define DAC_START_SETUP_TIME	5	/*   4.7 us */
+#define DAC_STOP_SETUP_TIME	4	/*   4.0 us */
+#define DAC_START_HOLD_TIME	5	/*   4.7 us */
+#define DAC_SCL_LOW_HOLD_TIME	5	/*   4.7 us */
+#define DAC_SCL_HIGH_HOLD_TIME	4	/*   4.0 us */
+#define DAC_DATA_SETUP_TIME	1	/*   250 ns */
+#define DAC_DATA_HOLD_TIME	1	/*   300 ns */
+#define DAC_LOW_SETUP_TIME	1	/*   300 ns */
+#define DAC_HIGH_SETUP_TIME	1	/*  1000 ns */
+
+/* the following is the overall data for the locomo chip */
+struct locomo {
+	struct device *dev;
+	unsigned long phys;
+	unsigned int irq;
+	int irq_base;
+	spinlock_t lock;
+	void __iomem *base;
+#ifdef CONFIG_PM
+	void *saved_state;
+#endif
+};
+
+struct locomo_dev_info {
+	unsigned long	offset;
+	unsigned long	length;
+	unsigned int	devid;
+	unsigned int	irq[1];
+	const char *	name;
+};
+
+/* All the locomo devices.  If offset is non-zero, the mapbase for the
+ * locomo_dev will be set to the chip base plus offset.  If offset is
+ * zero, then the mapbase for the locomo_dev will be set to zero.  An
+ * offset of zero means the device only uses GPIOs or other helper
+ * functions inside this file */
+static struct locomo_dev_info locomo_devices[] = {
+	{
+		.devid 		= LOCOMO_DEVID_KEYBOARD,
+		.irq		= { IRQ_LOCOMO_KEY },
+		.name		= "locomo-keyboard",
+		.offset		= LOCOMO_KEYBOARD,
+		.length		= 16,
+	},
+	{
+		.devid		= LOCOMO_DEVID_FRONTLIGHT,
+		.irq		= {},
+		.name		= "locomo-frontlight",
+		.offset		= LOCOMO_FRONTLIGHT,
+		.length		= 8,
+
+	},
+	{
+		.devid		= LOCOMO_DEVID_BACKLIGHT,
+		.irq		= {},
+		.name		= "locomo-backlight",
+		.offset		= LOCOMO_BACKLIGHT,
+		.length		= 8,
+	},
+	{
+		.devid		= LOCOMO_DEVID_AUDIO,
+		.irq		= {},
+		.name		= "locomo-audio",
+		.offset		= LOCOMO_AUDIO,
+		.length		= 4,
+	},
+	{
+		.devid		= LOCOMO_DEVID_LED,
+		.irq 		= {},
+		.name		= "locomo-led",
+		.offset		= LOCOMO_LED,
+		.length		= 8,
+	},
+	{
+		.devid		= LOCOMO_DEVID_UART,
+		.irq		= {},
+		.name		= "locomo-uart",
+		.offset		= 0,
+		.length		= 0,
+	},
+	{
+		.devid		= LOCOMO_DEVID_SPI,
+		.irq		= {},
+		.name		= "locomo-spi",
+		.offset		= LOCOMO_SPI,
+		.length		= 0x30,
+	},
+};
+
+static void locomo_handler(unsigned int irq, struct irq_desc *desc)
+{
+	struct locomo *lchip = irq_get_chip_data(irq);
+	int req, i;
+
+	/* Acknowledge the parent IRQ */
+	desc->irq_data.chip->irq_ack(&desc->irq_data);
+
+	/* check why this interrupt was generated */
+	req = locomo_readl(lchip->base + LOCOMO_ICR) & 0x0f00;
+
+	if (req) {
+		/* generate the next interrupt(s) */
+		irq = lchip->irq_base;
+		for (i = 0; i <= 3; i++, irq++) {
+			if (req & (0x0100 << i)) {
+				generic_handle_irq(irq);
+			}
+
+		}
+	}
+}
+
+static void locomo_ack_irq(struct irq_data *d)
+{
+}
+
+static void locomo_mask_irq(struct irq_data *d)
+{
+	struct locomo *lchip = irq_data_get_irq_chip_data(d);
+	unsigned int r;
+	r = locomo_readl(lchip->base + LOCOMO_ICR);
+	r &= ~(0x0010 << (d->irq - lchip->irq_base));
+	locomo_writel(r, lchip->base + LOCOMO_ICR);
+}
+
+static void locomo_unmask_irq(struct irq_data *d)
+{
+	struct locomo *lchip = irq_data_get_irq_chip_data(d);
+	unsigned int r;
+	r = locomo_readl(lchip->base + LOCOMO_ICR);
+	r |= (0x0010 << (d->irq - lchip->irq_base));
+	locomo_writel(r, lchip->base + LOCOMO_ICR);
+}
+
+static struct irq_chip locomo_chip = {
+	.name		= "LOCOMO",
+	.irq_ack	= locomo_ack_irq,
+	.irq_mask	= locomo_mask_irq,
+	.irq_unmask	= locomo_unmask_irq,
+};
+
+static void locomo_setup_irq(struct locomo *lchip)
+{
+	int irq = lchip->irq_base;
+
+	/*
+	 * Install handler for IRQ_LOCOMO_HW.
+	 */
+	irq_set_irq_type(lchip->irq, IRQ_TYPE_EDGE_FALLING);
+	irq_set_chip_data(lchip->irq, lchip);
+	irq_set_chained_handler(lchip->irq, locomo_handler);
+
+	/* Install handlers for IRQ_LOCOMO_* */
+	for ( ; irq <= lchip->irq_base + 3; irq++) {
+		irq_set_chip_and_handler(irq, &locomo_chip, handle_level_irq);
+		irq_set_chip_data(irq, lchip);
+		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+	}
+}
+
+
+static void locomo_dev_release(struct device *_dev)
+{
+	struct locomo_dev *dev = LOCOMO_DEV(_dev);
+
+	kfree(dev);
+}
+
+static int
+locomo_init_one_child(struct locomo *lchip, struct locomo_dev_info *info)
+{
+	struct locomo_dev *dev;
+	int ret;
+
+	dev = kzalloc(sizeof(struct locomo_dev), GFP_KERNEL);
+	if (!dev) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	/*
+	 * If the parent device has a DMA mask associated with it,
+	 * propagate it down to the children.
+	 */
+	if (lchip->dev->dma_mask) {
+		dev->dma_mask = *lchip->dev->dma_mask;
+		dev->dev.dma_mask = &dev->dma_mask;
+	}
+
+	dev_set_name(&dev->dev, "%s", info->name);
+	dev->devid	 = info->devid;
+	dev->dev.parent  = lchip->dev;
+	dev->dev.bus     = &locomo_bus_type;
+	dev->dev.release = locomo_dev_release;
+	dev->dev.coherent_dma_mask = lchip->dev->coherent_dma_mask;
+
+	if (info->offset)
+		dev->mapbase = lchip->base + info->offset;
+	else
+		dev->mapbase = 0;
+	dev->length = info->length;
+
+	dev->irq[0] = (lchip->irq_base == NO_IRQ) ?
+			NO_IRQ : lchip->irq_base + info->irq[0];
+
+	ret = device_register(&dev->dev);
+	if (ret) {
+ out:
+		kfree(dev);
+	}
+	return ret;
+}
+
+#ifdef CONFIG_PM
+
+struct locomo_save_data {
+	u16	LCM_GPO;
+	u16	LCM_SPICT;
+	u16	LCM_GPE;
+	u16	LCM_ASD;
+	u16	LCM_SPIMD;
+};
+
+static int locomo_suspend(struct platform_device *dev, pm_message_t state)
+{
+	struct locomo *lchip = platform_get_drvdata(dev);
+	struct locomo_save_data *save;
+	unsigned long flags;
+
+	save = kmalloc(sizeof(struct locomo_save_data), GFP_KERNEL);
+	if (!save)
+		return -ENOMEM;
+
+	lchip->saved_state = save;
+
+	spin_lock_irqsave(&lchip->lock, flags);
+
+	save->LCM_GPO     = locomo_readl(lchip->base + LOCOMO_GPO);	/* GPIO */
+	locomo_writel(0x00, lchip->base + LOCOMO_GPO);
+	save->LCM_SPICT   = locomo_readl(lchip->base + LOCOMO_SPI + LOCOMO_SPICT);	/* SPI */
+	locomo_writel(0x40, lchip->base + LOCOMO_SPI + LOCOMO_SPICT);
+	save->LCM_GPE     = locomo_readl(lchip->base + LOCOMO_GPE);	/* GPIO */
+	locomo_writel(0x00, lchip->base + LOCOMO_GPE);
+	save->LCM_ASD     = locomo_readl(lchip->base + LOCOMO_ASD);	/* ADSTART */
+	locomo_writel(0x00, lchip->base + LOCOMO_ASD);
+	save->LCM_SPIMD   = locomo_readl(lchip->base + LOCOMO_SPI + LOCOMO_SPIMD);	/* SPI */
+	locomo_writel(0x3C14, lchip->base + LOCOMO_SPI + LOCOMO_SPIMD);
+
+	locomo_writel(0x00, lchip->base + LOCOMO_PAIF);
+	locomo_writel(0x00, lchip->base + LOCOMO_DAC);
+	locomo_writel(0x00, lchip->base + LOCOMO_BACKLIGHT + LOCOMO_TC);
+
+	if ((locomo_readl(lchip->base + LOCOMO_LED + LOCOMO_LPT0) & 0x88) && (locomo_readl(lchip->base + LOCOMO_LED + LOCOMO_LPT1) & 0x88))
+		locomo_writel(0x00, lchip->base + LOCOMO_C32K); 	/* CLK32 off */
+	else
+		/* 18MHz already enabled, so no wait */
+		locomo_writel(0xc1, lchip->base + LOCOMO_C32K); 	/* CLK32 on */
+
+	locomo_writel(0x00, lchip->base + LOCOMO_TADC);		/* 18MHz clock off*/
+	locomo_writel(0x00, lchip->base + LOCOMO_AUDIO + LOCOMO_ACC);			/* 22MHz/24MHz clock off */
+	locomo_writel(0x00, lchip->base + LOCOMO_FRONTLIGHT + LOCOMO_ALS);			/* FL */
+
+	spin_unlock_irqrestore(&lchip->lock, flags);
+
+	return 0;
+}
+
+static int locomo_resume(struct platform_device *dev)
+{
+	struct locomo *lchip = platform_get_drvdata(dev);
+	struct locomo_save_data *save;
+	unsigned long r;
+	unsigned long flags;
+
+	save = lchip->saved_state;
+	if (!save)
+		return 0;
+
+	spin_lock_irqsave(&lchip->lock, flags);
+
+	locomo_writel(save->LCM_GPO, lchip->base + LOCOMO_GPO);
+	locomo_writel(save->LCM_SPICT, lchip->base + LOCOMO_SPI + LOCOMO_SPICT);
+	locomo_writel(save->LCM_GPE, lchip->base + LOCOMO_GPE);
+	locomo_writel(save->LCM_ASD, lchip->base + LOCOMO_ASD);
+	locomo_writel(save->LCM_SPIMD, lchip->base + LOCOMO_SPI + LOCOMO_SPIMD);
+
+	locomo_writel(0x00, lchip->base + LOCOMO_C32K);
+	locomo_writel(0x90, lchip->base + LOCOMO_TADC);
+
+	locomo_writel(0, lchip->base + LOCOMO_KEYBOARD + LOCOMO_KSC);
+	r = locomo_readl(lchip->base + LOCOMO_KEYBOARD + LOCOMO_KIC);
+	r &= 0xFEFF;
+	locomo_writel(r, lchip->base + LOCOMO_KEYBOARD + LOCOMO_KIC);
+	locomo_writel(0x1, lchip->base + LOCOMO_KEYBOARD + LOCOMO_KCMD);
+
+	spin_unlock_irqrestore(&lchip->lock, flags);
+
+	lchip->saved_state = NULL;
+	kfree(save);
+
+	return 0;
+}
+#endif
+
+
+/**
+ *	locomo_probe - probe for a single LoCoMo chip.
+ *	@phys_addr: physical address of device.
+ *
+ *	Probe for a LoCoMo chip.  This must be called
+ *	before any other locomo-specific code.
+ *
+ *	Returns:
+ *	%-ENODEV	device not found.
+ *	%-EBUSY		physical address already marked in-use.
+ *	%0		successful.
+ */
+static int
+__locomo_probe(struct device *me, struct resource *mem, int irq)
+{
+	struct locomo_platform_data *pdata = me->platform_data;
+	struct locomo *lchip;
+	unsigned long r;
+	int i, ret = -ENODEV;
+
+	lchip = kzalloc(sizeof(struct locomo), GFP_KERNEL);
+	if (!lchip)
+		return -ENOMEM;
+
+	spin_lock_init(&lchip->lock);
+
+	lchip->dev = me;
+	dev_set_drvdata(lchip->dev, lchip);
+
+	lchip->phys = mem->start;
+	lchip->irq = irq;
+	lchip->irq_base = (pdata) ? pdata->irq_base : NO_IRQ;
+
+	/*
+	 * Map the whole region.  This also maps the
+	 * registers for our children.
+	 */
+	lchip->base = ioremap(mem->start, PAGE_SIZE);
+	if (!lchip->base) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	/* locomo initialize */
+	locomo_writel(0, lchip->base + LOCOMO_ICR);
+	/* KEYBOARD */
+	locomo_writel(0, lchip->base + LOCOMO_KEYBOARD + LOCOMO_KIC);
+
+	/* GPIO */
+	locomo_writel(0, lchip->base + LOCOMO_GPO);
+	locomo_writel((LOCOMO_GPIO(1) | LOCOMO_GPIO(2) | LOCOMO_GPIO(13) | LOCOMO_GPIO(14))
+			, lchip->base + LOCOMO_GPE);
+	locomo_writel((LOCOMO_GPIO(1) | LOCOMO_GPIO(2) | LOCOMO_GPIO(13) | LOCOMO_GPIO(14))
+			, lchip->base + LOCOMO_GPD);
+	locomo_writel(0, lchip->base + LOCOMO_GIE);
+
+	/* Frontlight */
+	locomo_writel(0, lchip->base + LOCOMO_FRONTLIGHT + LOCOMO_ALS);
+	locomo_writel(0, lchip->base + LOCOMO_FRONTLIGHT + LOCOMO_ALD);
+
+	/* Longtime timer */
+	locomo_writel(0, lchip->base + LOCOMO_LTINT);
+	/* SPI */
+	locomo_writel(0, lchip->base + LOCOMO_SPI + LOCOMO_SPIIE);
+
+	locomo_writel(6 + 8 + 320 + 30 - 10, lchip->base + LOCOMO_ASD);
+	r = locomo_readl(lchip->base + LOCOMO_ASD);
+	r |= 0x8000;
+	locomo_writel(r, lchip->base + LOCOMO_ASD);
+
+	locomo_writel(6 + 8 + 320 + 30 - 10 - 128 + 4, lchip->base + LOCOMO_HSD);
+	r = locomo_readl(lchip->base + LOCOMO_HSD);
+	r |= 0x8000;
+	locomo_writel(r, lchip->base + LOCOMO_HSD);
+
+	locomo_writel(128 / 8, lchip->base + LOCOMO_HSC);
+
+	/* XON */
+	locomo_writel(0x80, lchip->base + LOCOMO_TADC);
+	udelay(1000);
+	/* CLK9MEN */
+	r = locomo_readl(lchip->base + LOCOMO_TADC);
+	r |= 0x10;
+	locomo_writel(r, lchip->base + LOCOMO_TADC);
+	udelay(100);
+
+	/* init DAC */
+	r = locomo_readl(lchip->base + LOCOMO_DAC);
+	r |= LOCOMO_DAC_SCLOEB | LOCOMO_DAC_SDAOEB;
+	locomo_writel(r, lchip->base + LOCOMO_DAC);
+
+	r = locomo_readl(lchip->base + LOCOMO_VER);
+	printk(KERN_INFO "LoCoMo Chip: %lu%lu\n", (r >> 8), (r & 0xff));
+
+	/*
+	 * The interrupt controller must be initialised before any
+	 * other device to ensure that the interrupts are available.
+	 */
+	if (lchip->irq != NO_IRQ && lchip->irq_base != NO_IRQ)
+		locomo_setup_irq(lchip);
+
+	for (i = 0; i < ARRAY_SIZE(locomo_devices); i++)
+		locomo_init_one_child(lchip, &locomo_devices[i]);
+	return 0;
+
+ out:
+	kfree(lchip);
+	return ret;
+}
+
+static int locomo_remove_child(struct device *dev, void *data)
+{
+	device_unregister(dev);
+	return 0;
+} 
+
+static void __locomo_remove(struct locomo *lchip)
+{
+	device_for_each_child(lchip->dev, NULL, locomo_remove_child);
+
+	if (lchip->irq != NO_IRQ) {
+		irq_set_chained_handler(lchip->irq, NULL);
+		irq_set_handler_data(lchip->irq, NULL);
+	}
+
+	iounmap(lchip->base);
+	kfree(lchip);
+}
+
+static int locomo_probe(struct platform_device *dev)
+{
+	struct resource *mem;
+	int irq;
+
+	mem = platform_get_resource(dev, IORESOURCE_MEM, 0);
+	if (!mem)
+		return -EINVAL;
+	irq = platform_get_irq(dev, 0);
+	if (irq < 0)
+		return -ENXIO;
+
+	return __locomo_probe(&dev->dev, mem, irq);
+}
+
+static int locomo_remove(struct platform_device *dev)
+{
+	struct locomo *lchip = platform_get_drvdata(dev);
+
+	if (lchip) {
+		__locomo_remove(lchip);
+		platform_set_drvdata(dev, NULL);
+	}
+
+	return 0;
+}
+
+/*
+ *	Not sure if this should be on the system bus or not yet.
+ *	We really want some way to register a system device at
+ *	the per-machine level, and then have this driver pick
+ *	up the registered devices.
+ */
+static struct platform_driver locomo_device_driver = {
+	.probe		= locomo_probe,
+	.remove		= locomo_remove,
+#ifdef CONFIG_PM
+	.suspend	= locomo_suspend,
+	.resume		= locomo_resume,
+#endif
+	.driver		= {
+		.name	= "locomo",
+	},
+};
+
+/*
+ *	Get the parent device driver (us) structure
+ *	from a child function device
+ */
+static inline struct locomo *locomo_chip_driver(struct locomo_dev *ldev)
+{
+	return (struct locomo *)dev_get_drvdata(ldev->dev.parent);
+}
+
+void locomo_gpio_set_dir(struct device *dev, unsigned int bits, unsigned int dir)
+{
+	struct locomo *lchip = dev_get_drvdata(dev);
+	unsigned long flags;
+	unsigned int r;
+
+	if (!lchip)
+		return;
+
+	spin_lock_irqsave(&lchip->lock, flags);
+
+	r = locomo_readl(lchip->base + LOCOMO_GPD);
+	if (dir)
+		r |= bits;
+	else
+		r &= ~bits;
+	locomo_writel(r, lchip->base + LOCOMO_GPD);
+
+	r = locomo_readl(lchip->base + LOCOMO_GPE);
+	if (dir)
+		r |= bits;
+	else
+		r &= ~bits;
+	locomo_writel(r, lchip->base + LOCOMO_GPE);
+
+	spin_unlock_irqrestore(&lchip->lock, flags);
+}
+EXPORT_SYMBOL(locomo_gpio_set_dir);
+
+int locomo_gpio_read_level(struct device *dev, unsigned int bits)
+{
+	struct locomo *lchip = dev_get_drvdata(dev);
+	unsigned long flags;
+	unsigned int ret;
+
+	if (!lchip)
+		return -ENODEV;
+
+	spin_lock_irqsave(&lchip->lock, flags);
+	ret = locomo_readl(lchip->base + LOCOMO_GPL);
+	spin_unlock_irqrestore(&lchip->lock, flags);
+
+	ret &= bits;
+	return ret;
+}
+EXPORT_SYMBOL(locomo_gpio_read_level);
+
+int locomo_gpio_read_output(struct device *dev, unsigned int bits)
+{
+	struct locomo *lchip = dev_get_drvdata(dev);
+	unsigned long flags;
+	unsigned int ret;
+
+	if (!lchip)
+		return -ENODEV;
+
+	spin_lock_irqsave(&lchip->lock, flags);
+	ret = locomo_readl(lchip->base + LOCOMO_GPO);
+	spin_unlock_irqrestore(&lchip->lock, flags);
+
+	ret &= bits;
+	return ret;
+}
+EXPORT_SYMBOL(locomo_gpio_read_output);
+
+void locomo_gpio_write(struct device *dev, unsigned int bits, unsigned int set)
+{
+	struct locomo *lchip = dev_get_drvdata(dev);
+	unsigned long flags;
+	unsigned int r;
+
+	if (!lchip)
+		return;
+
+	spin_lock_irqsave(&lchip->lock, flags);
+
+	r = locomo_readl(lchip->base + LOCOMO_GPO);
+	if (set)
+		r |= bits;
+	else
+		r &= ~bits;
+	locomo_writel(r, lchip->base + LOCOMO_GPO);
+
+	spin_unlock_irqrestore(&lchip->lock, flags);
+}
+EXPORT_SYMBOL(locomo_gpio_write);
+
+static void locomo_m62332_sendbit(void *mapbase, int bit)
+{
+	unsigned int r;
+
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r &=  ~(LOCOMO_DAC_SCLOEB);
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_LOW_SETUP_TIME);	/* 300 nsec */
+	udelay(DAC_DATA_HOLD_TIME);	/* 300 nsec */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r &=  ~(LOCOMO_DAC_SCLOEB);
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_LOW_SETUP_TIME);	/* 300 nsec */
+	udelay(DAC_SCL_LOW_HOLD_TIME);	/* 4.7 usec */
+
+	if (bit & 1) {
+		r = locomo_readl(mapbase + LOCOMO_DAC);
+		r |=  LOCOMO_DAC_SDAOEB;
+		locomo_writel(r, mapbase + LOCOMO_DAC);
+		udelay(DAC_HIGH_SETUP_TIME);	/* 1000 nsec */
+	} else {
+		r = locomo_readl(mapbase + LOCOMO_DAC);
+		r &=  ~(LOCOMO_DAC_SDAOEB);
+		locomo_writel(r, mapbase + LOCOMO_DAC);
+		udelay(DAC_LOW_SETUP_TIME);	/* 300 nsec */
+	}
+
+	udelay(DAC_DATA_SETUP_TIME);	/* 250 nsec */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r |=  LOCOMO_DAC_SCLOEB;
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_HIGH_SETUP_TIME);	/* 1000 nsec */
+	udelay(DAC_SCL_HIGH_HOLD_TIME);	/*  4.0 usec */
+}
+
+void locomo_m62332_senddata(struct locomo_dev *ldev, unsigned int dac_data, int channel)
+{
+	struct locomo *lchip = locomo_chip_driver(ldev);
+	int i;
+	unsigned char data;
+	unsigned int r;
+	void *mapbase = lchip->base;
+	unsigned long flags;
+
+	spin_lock_irqsave(&lchip->lock, flags);
+
+	/* Start */
+	udelay(DAC_BUS_FREE_TIME);	/* 5.0 usec */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r |=  LOCOMO_DAC_SCLOEB | LOCOMO_DAC_SDAOEB;
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_HIGH_SETUP_TIME);	/* 1000 nsec */
+	udelay(DAC_SCL_HIGH_HOLD_TIME);	/* 4.0 usec */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r &=  ~(LOCOMO_DAC_SDAOEB);
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_START_HOLD_TIME);	/* 5.0 usec */
+	udelay(DAC_DATA_HOLD_TIME);	/* 300 nsec */
+
+	/* Send slave address and W bit (LSB is W bit) */
+	data = (M62332_SLAVE_ADDR << 1) | M62332_W_BIT;
+	for (i = 1; i <= 8; i++) {
+		locomo_m62332_sendbit(mapbase, data >> (8 - i));
+	}
+
+	/* Check A bit */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r &=  ~(LOCOMO_DAC_SCLOEB);
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_LOW_SETUP_TIME);	/* 300 nsec */
+	udelay(DAC_SCL_LOW_HOLD_TIME);	/* 4.7 usec */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r &=  ~(LOCOMO_DAC_SDAOEB);
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_LOW_SETUP_TIME);	/* 300 nsec */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r |=  LOCOMO_DAC_SCLOEB;
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_HIGH_SETUP_TIME);	/* 1000 nsec */
+	udelay(DAC_SCL_HIGH_HOLD_TIME);	/* 4.7 usec */
+	if (locomo_readl(mapbase + LOCOMO_DAC) & LOCOMO_DAC_SDAOEB) {	/* High is error */
+		printk(KERN_WARNING "locomo: m62332_senddata Error 1\n");
+		goto out;
+	}
+
+	/* Send Sub address (LSB is channel select) */
+	/*    channel = 0 : ch1 select              */
+	/*            = 1 : ch2 select              */
+	data = M62332_SUB_ADDR + channel;
+	for (i = 1; i <= 8; i++) {
+		locomo_m62332_sendbit(mapbase, data >> (8 - i));
+	}
+
+	/* Check A bit */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r &=  ~(LOCOMO_DAC_SCLOEB);
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_LOW_SETUP_TIME);	/* 300 nsec */
+	udelay(DAC_SCL_LOW_HOLD_TIME);	/* 4.7 usec */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r &=  ~(LOCOMO_DAC_SDAOEB);
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_LOW_SETUP_TIME);	/* 300 nsec */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r |=  LOCOMO_DAC_SCLOEB;
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_HIGH_SETUP_TIME);	/* 1000 nsec */
+	udelay(DAC_SCL_HIGH_HOLD_TIME);	/* 4.7 usec */
+	if (locomo_readl(mapbase + LOCOMO_DAC) & LOCOMO_DAC_SDAOEB) {	/* High is error */
+		printk(KERN_WARNING "locomo: m62332_senddata Error 2\n");
+		goto out;
+	}
+
+	/* Send DAC data */
+	for (i = 1; i <= 8; i++) {
+		locomo_m62332_sendbit(mapbase, dac_data >> (8 - i));
+	}
+
+	/* Check A bit */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r &=  ~(LOCOMO_DAC_SCLOEB);
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_LOW_SETUP_TIME);	/* 300 nsec */
+	udelay(DAC_SCL_LOW_HOLD_TIME);	/* 4.7 usec */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r &=  ~(LOCOMO_DAC_SDAOEB);
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_LOW_SETUP_TIME);	/* 300 nsec */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r |=  LOCOMO_DAC_SCLOEB;
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_HIGH_SETUP_TIME);	/* 1000 nsec */
+	udelay(DAC_SCL_HIGH_HOLD_TIME);	/* 4.7 usec */
+	if (locomo_readl(mapbase + LOCOMO_DAC) & LOCOMO_DAC_SDAOEB) {	/* High is error */
+		printk(KERN_WARNING "locomo: m62332_senddata Error 3\n");
+	}
+
+out:
+	/* stop */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r &=  ~(LOCOMO_DAC_SCLOEB);
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_LOW_SETUP_TIME);	/* 300 nsec */
+	udelay(DAC_SCL_LOW_HOLD_TIME);	/* 4.7 usec */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r |=  LOCOMO_DAC_SCLOEB;
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_HIGH_SETUP_TIME);	/* 1000 nsec */
+	udelay(DAC_SCL_HIGH_HOLD_TIME);	/* 4 usec */
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r |=  LOCOMO_DAC_SDAOEB;
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_HIGH_SETUP_TIME);	/* 1000 nsec */
+	udelay(DAC_SCL_HIGH_HOLD_TIME);	/* 4 usec */
+
+	r = locomo_readl(mapbase + LOCOMO_DAC);
+	r |=  LOCOMO_DAC_SCLOEB | LOCOMO_DAC_SDAOEB;
+	locomo_writel(r, mapbase + LOCOMO_DAC);
+	udelay(DAC_LOW_SETUP_TIME);	/* 1000 nsec */
+	udelay(DAC_SCL_LOW_HOLD_TIME);	/* 4.7 usec */
+
+	spin_unlock_irqrestore(&lchip->lock, flags);
+}
+EXPORT_SYMBOL(locomo_m62332_senddata);
+
+/*
+ *	Frontlight control
+ */
+
+void locomo_frontlight_set(struct locomo_dev *dev, int duty, int vr, int bpwf)
+{
+	unsigned long flags;
+	struct locomo *lchip = locomo_chip_driver(dev);
+
+	if (vr)
+		locomo_gpio_write(dev->dev.parent, LOCOMO_GPIO_FL_VR, 1);
+	else
+		locomo_gpio_write(dev->dev.parent, LOCOMO_GPIO_FL_VR, 0);
+
+	spin_lock_irqsave(&lchip->lock, flags);
+	locomo_writel(bpwf, lchip->base + LOCOMO_FRONTLIGHT + LOCOMO_ALS);
+	udelay(100);
+	locomo_writel(duty, lchip->base + LOCOMO_FRONTLIGHT + LOCOMO_ALD);
+	locomo_writel(bpwf | LOCOMO_ALC_EN, lchip->base + LOCOMO_FRONTLIGHT + LOCOMO_ALS);
+	spin_unlock_irqrestore(&lchip->lock, flags);
+}
+EXPORT_SYMBOL(locomo_frontlight_set);
+
+/*
+ *	LoCoMo "Register Access Bus."
+ *
+ *	We model this as a regular bus type, and hang devices directly
+ *	off this.
+ */
+static int locomo_match(struct device *_dev, struct device_driver *_drv)
+{
+	struct locomo_dev *dev = LOCOMO_DEV(_dev);
+	struct locomo_driver *drv = LOCOMO_DRV(_drv);
+
+	return dev->devid == drv->devid;
+}
+
+static int locomo_bus_suspend(struct device *dev, pm_message_t state)
+{
+	struct locomo_dev *ldev = LOCOMO_DEV(dev);
+	struct locomo_driver *drv = LOCOMO_DRV(dev->driver);
+	int ret = 0;
+
+	if (drv && drv->suspend)
+		ret = drv->suspend(ldev, state);
+	return ret;
+}
+
+static int locomo_bus_resume(struct device *dev)
+{
+	struct locomo_dev *ldev = LOCOMO_DEV(dev);
+	struct locomo_driver *drv = LOCOMO_DRV(dev->driver);
+	int ret = 0;
+
+	if (drv && drv->resume)
+		ret = drv->resume(ldev);
+	return ret;
+}
+
+static int locomo_bus_probe(struct device *dev)
+{
+	struct locomo_dev *ldev = LOCOMO_DEV(dev);
+	struct locomo_driver *drv = LOCOMO_DRV(dev->driver);
+	int ret = -ENODEV;
+
+	if (drv->probe)
+		ret = drv->probe(ldev);
+	return ret;
+}
+
+static int locomo_bus_remove(struct device *dev)
+{
+	struct locomo_dev *ldev = LOCOMO_DEV(dev);
+	struct locomo_driver *drv = LOCOMO_DRV(dev->driver);
+	int ret = 0;
+
+	if (drv->remove)
+		ret = drv->remove(ldev);
+	return ret;
+}
+
+struct bus_type locomo_bus_type = {
+	.name		= "locomo-bus",
+	.match		= locomo_match,
+	.probe		= locomo_bus_probe,
+	.remove		= locomo_bus_remove,
+	.suspend	= locomo_bus_suspend,
+	.resume		= locomo_bus_resume,
+};
+
+int locomo_driver_register(struct locomo_driver *driver)
+{
+	driver->drv.bus = &locomo_bus_type;
+	return driver_register(&driver->drv);
+}
+EXPORT_SYMBOL(locomo_driver_register);
+
+void locomo_driver_unregister(struct locomo_driver *driver)
+{
+	driver_unregister(&driver->drv);
+}
+EXPORT_SYMBOL(locomo_driver_unregister);
+
+static int __init locomo_init(void)
+{
+	int ret = bus_register(&locomo_bus_type);
+	if (ret == 0)
+		platform_driver_register(&locomo_device_driver);
+	return ret;
+}
+
+static void __exit locomo_exit(void)
+{
+	platform_driver_unregister(&locomo_device_driver);
+	bus_unregister(&locomo_bus_type);
+}
+
+module_init(locomo_init);
+module_exit(locomo_exit);
+
+MODULE_DESCRIPTION("Sharp LoCoMo core driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("John Lenz <lenz@cs.wisc.edu>");

arch/arm/common/mcpm_entry.c

@@ -0,0 +1,348 @@
+/*
+ * arch/arm/common/mcpm_entry.c -- entry point for multi-cluster PM
+ *
+ * Created by:  Nicolas Pitre, March 2012
+ * Copyright:   (C) 2012-2013  Linaro Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/irqflags.h>
+#include <linux/cpu_pm.h>
+
+#include <asm/mcpm.h>
+#include <asm/cacheflush.h>
+#include <asm/idmap.h>
+#include <asm/cputype.h>
+#include <asm/suspend.h>
+
+extern unsigned long mcpm_entry_vectors[MAX_NR_CLUSTERS][MAX_CPUS_PER_CLUSTER];
+
+void mcpm_set_entry_vector(unsigned cpu, unsigned cluster, void *ptr)
+{
+	unsigned long val = ptr ? virt_to_phys(ptr) : 0;
+	mcpm_entry_vectors[cluster][cpu] = val;
+	sync_cache_w(&mcpm_entry_vectors[cluster][cpu]);
+}
+
+extern unsigned long mcpm_entry_early_pokes[MAX_NR_CLUSTERS][MAX_CPUS_PER_CLUSTER][2];
+
+void mcpm_set_early_poke(unsigned cpu, unsigned cluster,
+			 unsigned long poke_phys_addr, unsigned long poke_val)
+{
+	unsigned long *poke = &mcpm_entry_early_pokes[cluster][cpu][0];
+	poke[0] = poke_phys_addr;
+	poke[1] = poke_val;
+	__sync_cache_range_w(poke, 2 * sizeof(*poke));
+}
+
+static const struct mcpm_platform_ops *platform_ops;
+
+int __init mcpm_platform_register(const struct mcpm_platform_ops *ops)
+{
+	if (platform_ops)
+		return -EBUSY;
+	platform_ops = ops;
+	return 0;
+}
+
+bool mcpm_is_available(void)
+{
+	return (platform_ops) ? true : false;
+}
+
+int mcpm_cpu_power_up(unsigned int cpu, unsigned int cluster)
+{
+	if (!platform_ops)
+		return -EUNATCH; /* try not to shadow power_up errors */
+	might_sleep();
+	return platform_ops->power_up(cpu, cluster);
+}
+
+typedef void (*phys_reset_t)(unsigned long);
+
+void mcpm_cpu_power_down(void)
+{
+	phys_reset_t phys_reset;
+
+	if (WARN_ON_ONCE(!platform_ops || !platform_ops->power_down))
+		return;
+	BUG_ON(!irqs_disabled());
+
+	/*
+	 * Do this before calling into the power_down method,
+	 * as it might not always be safe to do afterwards.
+	 */
+	setup_mm_for_reboot();
+
+	platform_ops->power_down();
+
+	/*
+	 * It is possible for a power_up request to happen concurrently
+	 * with a power_down request for the same CPU. In this case the
+	 * power_down method might not be able to actually enter a
+	 * powered down state with the WFI instruction if the power_up
+	 * method has removed the required reset condition.  The
+	 * power_down method is then allowed to return. We must perform
+	 * a re-entry in the kernel as if the power_up method just had
+	 * deasserted reset on the CPU.
+	 *
+	 * To simplify race issues, the platform specific implementation
+	 * must accommodate for the possibility of unordered calls to
+	 * power_down and power_up with a usage count. Therefore, if a
+	 * call to power_up is issued for a CPU that is not down, then
+	 * the next call to power_down must not attempt a full shutdown
+	 * but only do the minimum (normally disabling L1 cache and CPU
+	 * coherency) and return just as if a concurrent power_up request
+	 * had happened as described above.
+	 */
+
+	phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset);
+	phys_reset(virt_to_phys(mcpm_entry_point));
+
+	/* should never get here */
+	BUG();
+}
+
+int mcpm_wait_for_cpu_powerdown(unsigned int cpu, unsigned int cluster)
+{
+	int ret;
+
+	if (WARN_ON_ONCE(!platform_ops || !platform_ops->wait_for_powerdown))
+		return -EUNATCH;
+
+	ret = platform_ops->wait_for_powerdown(cpu, cluster);
+	if (ret)
+		pr_warn("%s: cpu %u, cluster %u failed to power down (%d)\n",
+			__func__, cpu, cluster, ret);
+
+	return ret;
+}
+
+void mcpm_cpu_suspend(u64 expected_residency)
+{
+	phys_reset_t phys_reset;
+
+	if (WARN_ON_ONCE(!platform_ops || !platform_ops->suspend))
+		return;
+	BUG_ON(!irqs_disabled());
+
+	/* Very similar to mcpm_cpu_power_down() */
+	setup_mm_for_reboot();
+	platform_ops->suspend(expected_residency);
+	phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset);
+	phys_reset(virt_to_phys(mcpm_entry_point));
+	BUG();
+}
+
+int mcpm_cpu_powered_up(void)
+{
+	if (!platform_ops)
+		return -EUNATCH;
+	if (platform_ops->powered_up)
+		platform_ops->powered_up();
+	return 0;
+}
+
+#ifdef CONFIG_ARM_CPU_SUSPEND
+
+static int __init nocache_trampoline(unsigned long _arg)
+{
+	void (*cache_disable)(void) = (void *)_arg;
+	unsigned int mpidr = read_cpuid_mpidr();
+	unsigned int cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+	unsigned int cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+	phys_reset_t phys_reset;
+
+	mcpm_set_entry_vector(cpu, cluster, cpu_resume);
+	setup_mm_for_reboot();
+
+	__mcpm_cpu_going_down(cpu, cluster);
+	BUG_ON(!__mcpm_outbound_enter_critical(cpu, cluster));
+	cache_disable();
+	__mcpm_outbound_leave_critical(cluster, CLUSTER_DOWN);
+	__mcpm_cpu_down(cpu, cluster);
+
+	phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset);
+	phys_reset(virt_to_phys(mcpm_entry_point));
+	BUG();
+}
+
+int __init mcpm_loopback(void (*cache_disable)(void))
+{
+	int ret;
+
+	/*
+	 * We're going to soft-restart the current CPU through the
+	 * low-level MCPM code by leveraging the suspend/resume
+	 * infrastructure. Let's play it safe by using cpu_pm_enter()
+	 * in case the CPU init code path resets the VFP or similar.
+	 */
+	local_irq_disable();
+	local_fiq_disable();
+	ret = cpu_pm_enter();
+	if (!ret) {
+		ret = cpu_suspend((unsigned long)cache_disable, nocache_trampoline);
+		cpu_pm_exit();
+	}
+	local_fiq_enable();
+	local_irq_enable();
+	if (ret)
+		pr_err("%s returned %d\n", __func__, ret);
+	return ret;
+}
+
+#endif
+
+struct sync_struct mcpm_sync;
+
+/*
+ * __mcpm_cpu_going_down: Indicates that the cpu is being torn down.
+ *    This must be called at the point of committing to teardown of a CPU.
+ *    The CPU cache (SCTRL.C bit) is expected to still be active.
+ */
+void __mcpm_cpu_going_down(unsigned int cpu, unsigned int cluster)
+{
+	mcpm_sync.clusters[cluster].cpus[cpu].cpu = CPU_GOING_DOWN;
+	sync_cache_w(&mcpm_sync.clusters[cluster].cpus[cpu].cpu);
+}
+
+/*
+ * __mcpm_cpu_down: Indicates that cpu teardown is complete and that the
+ *    cluster can be torn down without disrupting this CPU.
+ *    To avoid deadlocks, this must be called before a CPU is powered down.
+ *    The CPU cache (SCTRL.C bit) is expected to be off.
+ *    However L2 cache might or might not be active.
+ */
+void __mcpm_cpu_down(unsigned int cpu, unsigned int cluster)
+{
+	dmb();
+	mcpm_sync.clusters[cluster].cpus[cpu].cpu = CPU_DOWN;
+	sync_cache_w(&mcpm_sync.clusters[cluster].cpus[cpu].cpu);
+	sev();
+}
+
+/*
+ * __mcpm_outbound_leave_critical: Leave the cluster teardown critical section.
+ * @state: the final state of the cluster:
+ *     CLUSTER_UP: no destructive teardown was done and the cluster has been
+ *         restored to the previous state (CPU cache still active); or
+ *     CLUSTER_DOWN: the cluster has been torn-down, ready for power-off
+ *         (CPU cache disabled, L2 cache either enabled or disabled).
+ */
+void __mcpm_outbound_leave_critical(unsigned int cluster, int state)
+{
+	dmb();
+	mcpm_sync.clusters[cluster].cluster = state;
+	sync_cache_w(&mcpm_sync.clusters[cluster].cluster);
+	sev();
+}
+
+/*
+ * __mcpm_outbound_enter_critical: Enter the cluster teardown critical section.
+ * This function should be called by the last man, after local CPU teardown
+ * is complete.  CPU cache expected to be active.
+ *
+ * Returns:
+ *     false: the critical section was not entered because an inbound CPU was
+ *         observed, or the cluster is already being set up;
+ *     true: the critical section was entered: it is now safe to tear down the
+ *         cluster.
+ */
+bool __mcpm_outbound_enter_critical(unsigned int cpu, unsigned int cluster)
+{
+	unsigned int i;
+	struct mcpm_sync_struct *c = &mcpm_sync.clusters[cluster];
+
+	/* Warn inbound CPUs that the cluster is being torn down: */
+	c->cluster = CLUSTER_GOING_DOWN;
+	sync_cache_w(&c->cluster);
+
+	/* Back out if the inbound cluster is already in the critical region: */
+	sync_cache_r(&c->inbound);
+	if (c->inbound == INBOUND_COMING_UP)
+		goto abort;
+
+	/*
+	 * Wait for all CPUs to get out of the GOING_DOWN state, so that local
+	 * teardown is complete on each CPU before tearing down the cluster.
+	 *
+	 * If any CPU has been woken up again from the DOWN state, then we
+	 * shouldn't be taking the cluster down at all: abort in that case.
+	 */
+	sync_cache_r(&c->cpus);
+	for (i = 0; i < MAX_CPUS_PER_CLUSTER; i++) {
+		int cpustate;
+
+		if (i == cpu)
+			continue;
+
+		while (1) {
+			cpustate = c->cpus[i].cpu;
+			if (cpustate != CPU_GOING_DOWN)
+				break;
+
+			wfe();
+			sync_cache_r(&c->cpus[i].cpu);
+		}
+
+		switch (cpustate) {
+		case CPU_DOWN:
+			continue;
+
+		default:
+			goto abort;
+		}
+	}
+
+	return true;
+
+abort:
+	__mcpm_outbound_leave_critical(cluster, CLUSTER_UP);
+	return false;
+}
+
+int __mcpm_cluster_state(unsigned int cluster)
+{
+	sync_cache_r(&mcpm_sync.clusters[cluster].cluster);
+	return mcpm_sync.clusters[cluster].cluster;
+}
+
+extern unsigned long mcpm_power_up_setup_phys;
+
+int __init mcpm_sync_init(
+	void (*power_up_setup)(unsigned int affinity_level))
+{
+	unsigned int i, j, mpidr, this_cluster;
+
+	BUILD_BUG_ON(MCPM_SYNC_CLUSTER_SIZE * MAX_NR_CLUSTERS != sizeof mcpm_sync);
+	BUG_ON((unsigned long)&mcpm_sync & (__CACHE_WRITEBACK_GRANULE - 1));
+
+	/*
+	 * Set initial CPU and cluster states.
+	 * Only one cluster is assumed to be active at this point.
+	 */
+	for (i = 0; i < MAX_NR_CLUSTERS; i++) {
+		mcpm_sync.clusters[i].cluster = CLUSTER_DOWN;
+		mcpm_sync.clusters[i].inbound = INBOUND_NOT_COMING_UP;
+		for (j = 0; j < MAX_CPUS_PER_CLUSTER; j++)
+			mcpm_sync.clusters[i].cpus[j].cpu = CPU_DOWN;
+	}
+	mpidr = read_cpuid_mpidr();
+	this_cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+	for_each_online_cpu(i)
+		mcpm_sync.clusters[this_cluster].cpus[i].cpu = CPU_UP;
+	mcpm_sync.clusters[this_cluster].cluster = CLUSTER_UP;
+	sync_cache_w(&mcpm_sync);
+
+	if (power_up_setup) {
+		mcpm_power_up_setup_phys = virt_to_phys(power_up_setup);
+		sync_cache_w(&mcpm_power_up_setup_phys);
+	}
+
+	return 0;
+}

arch/arm/common/mcpm_head.S

@@ -0,0 +1,233 @@
+/*
+ * arch/arm/common/mcpm_head.S -- kernel entry point for multi-cluster PM
+ *
+ * Created by:  Nicolas Pitre, March 2012
+ * Copyright:   (C) 2012-2013  Linaro Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *
+ * Refer to Documentation/arm/cluster-pm-race-avoidance.txt
+ * for details of the synchronisation algorithms used here.
+ */
+
+#include <linux/linkage.h>
+#include <asm/mcpm.h>
+#include <asm/assembler.h>
+
+#include "vlock.h"
+
+.if MCPM_SYNC_CLUSTER_CPUS
+.error "cpus must be the first member of struct mcpm_sync_struct"
+.endif
+
+	.macro	pr_dbg	string
+#if defined(CONFIG_DEBUG_LL) && defined(DEBUG)
+	b	1901f
+1902:	.asciz	"CPU"
+1903:	.asciz	" cluster"
+1904:	.asciz	": \string"
+	.align
+1901:	adr	r0, 1902b
+	bl	printascii
+	mov	r0, r9
+	bl	printhex2
+	adr	r0, 1903b
+	bl	printascii
+	mov	r0, r10
+	bl	printhex2
+	adr	r0, 1904b
+	bl	printascii
+#endif
+	.endm
+
+	.arm
+	.align
+
+ENTRY(mcpm_entry_point)
+
+ ARM_BE8(setend        be)
+ THUMB(	adr	r12, BSYM(1f)	)
+ THUMB(	bx	r12		)
+ THUMB(	.thumb			)
+1:
+	mrc	p15, 0, r0, c0, c0, 5		@ MPIDR
+	ubfx	r9, r0, #0, #8			@ r9 = cpu
+	ubfx	r10, r0, #8, #8			@ r10 = cluster
+	mov	r3, #MAX_CPUS_PER_CLUSTER
+	mla	r4, r3, r10, r9			@ r4 = canonical CPU index
+	cmp	r4, #(MAX_CPUS_PER_CLUSTER * MAX_NR_CLUSTERS)
+	blo	2f
+
+	/* We didn't expect this CPU.  Try to cheaply make it quiet. */
+1:	wfi
+	wfe
+	b	1b
+
+2:	pr_dbg	"kernel mcpm_entry_point\n"
+
+	/*
+	 * MMU is off so we need to get to various variables in a
+	 * position independent way.
+	 */
+	adr	r5, 3f
+	ldmia	r5, {r0, r6, r7, r8, r11}
+	add	r0, r5, r0			@ r0 = mcpm_entry_early_pokes
+	add	r6, r5, r6			@ r6 = mcpm_entry_vectors
+	ldr	r7, [r5, r7]			@ r7 = mcpm_power_up_setup_phys
+	add	r8, r5, r8			@ r8 = mcpm_sync
+	add	r11, r5, r11			@ r11 = first_man_locks
+
+	@ Perform an early poke, if any
+	add	r0, r0, r4, lsl #3
+	ldmia	r0, {r0, r1}
+	teq	r0, #0
+	strne	r1, [r0]
+
+	mov	r0, #MCPM_SYNC_CLUSTER_SIZE
+	mla	r8, r0, r10, r8			@ r8 = sync cluster base
+
+	@ Signal that this CPU is coming UP:
+	mov	r0, #CPU_COMING_UP
+	mov	r5, #MCPM_SYNC_CPU_SIZE
+	mla	r5, r9, r5, r8			@ r5 = sync cpu address
+	strb	r0, [r5]
+
+	@ At this point, the cluster cannot unexpectedly enter the GOING_DOWN
+	@ state, because there is at least one active CPU (this CPU).
+
+	mov	r0, #VLOCK_SIZE
+	mla	r11, r0, r10, r11		@ r11 = cluster first man lock
+	mov	r0, r11
+	mov	r1, r9				@ cpu
+	bl	vlock_trylock			@ implies DMB
+
+	cmp	r0, #0				@ failed to get the lock?
+	bne	mcpm_setup_wait		@ wait for cluster setup if so
+
+	ldrb	r0, [r8, #MCPM_SYNC_CLUSTER_CLUSTER]
+	cmp	r0, #CLUSTER_UP			@ cluster already up?
+	bne	mcpm_setup			@ if not, set up the cluster
+
+	@ Otherwise, release the first man lock and skip setup:
+	mov	r0, r11
+	bl	vlock_unlock
+	b	mcpm_setup_complete
+
+mcpm_setup:
+	@ Control dependency implies strb not observable before previous ldrb.
+
+	@ Signal that the cluster is being brought up:
+	mov	r0, #INBOUND_COMING_UP
+	strb	r0, [r8, #MCPM_SYNC_CLUSTER_INBOUND]
+	dmb
+
+	@ Any CPU trying to take the cluster into CLUSTER_GOING_DOWN from this
+	@ point onwards will observe INBOUND_COMING_UP and abort.
+
+	@ Wait for any previously-pending cluster teardown operations to abort
+	@ or complete:
+mcpm_teardown_wait:
+	ldrb	r0, [r8, #MCPM_SYNC_CLUSTER_CLUSTER]
+	cmp	r0, #CLUSTER_GOING_DOWN
+	bne	first_man_setup
+	wfe
+	b	mcpm_teardown_wait
+
+first_man_setup:
+	dmb
+
+	@ If the outbound gave up before teardown started, skip cluster setup:
+
+	cmp	r0, #CLUSTER_UP
+	beq	mcpm_setup_leave
+
+	@ power_up_setup is now responsible for setting up the cluster:
+
+	cmp	r7, #0
+	mov	r0, #1		@ second (cluster) affinity level
+	blxne	r7		@ Call power_up_setup if defined
+	dmb
+
+	mov	r0, #CLUSTER_UP
+	strb	r0, [r8, #MCPM_SYNC_CLUSTER_CLUSTER]
+	dmb
+
+mcpm_setup_leave:
+	@ Leave the cluster setup critical section:
+
+	mov	r0, #INBOUND_NOT_COMING_UP
+	strb	r0, [r8, #MCPM_SYNC_CLUSTER_INBOUND]
+	dsb	st
+	sev
+
+	mov	r0, r11
+	bl	vlock_unlock	@ implies DMB
+	b	mcpm_setup_complete
+
+	@ In the contended case, non-first men wait here for cluster setup
+	@ to complete:
+mcpm_setup_wait:
+	ldrb	r0, [r8, #MCPM_SYNC_CLUSTER_CLUSTER]
+	cmp	r0, #CLUSTER_UP
+	wfene
+	bne	mcpm_setup_wait
+	dmb
+
+mcpm_setup_complete:
+	@ If a platform-specific CPU setup hook is needed, it is
+	@ called from here.
+
+	cmp	r7, #0
+	mov	r0, #0		@ first (CPU) affinity level
+	blxne	r7		@ Call power_up_setup if defined
+	dmb
+
+	@ Mark the CPU as up:
+
+	mov	r0, #CPU_UP
+	strb	r0, [r5]
+
+	@ Observability order of CPU_UP and opening of the gate does not matter.
+
+mcpm_entry_gated:
+	ldr	r5, [r6, r4, lsl #2]		@ r5 = CPU entry vector
+	cmp	r5, #0
+	wfeeq
+	beq	mcpm_entry_gated
+	dmb
+
+	pr_dbg	"released\n"
+	bx	r5
+
+	.align	2
+
+3:	.word	mcpm_entry_early_pokes - .
+	.word	mcpm_entry_vectors - 3b
+	.word	mcpm_power_up_setup_phys - 3b
+	.word	mcpm_sync - 3b
+	.word	first_man_locks - 3b
+
+ENDPROC(mcpm_entry_point)
+
+	.bss
+
+	.align	CACHE_WRITEBACK_ORDER
+	.type	first_man_locks, #object
+first_man_locks:
+	.space	VLOCK_SIZE * MAX_NR_CLUSTERS
+	.align	CACHE_WRITEBACK_ORDER
+
+	.type	mcpm_entry_vectors, #object
+ENTRY(mcpm_entry_vectors)
+	.space	4 * MAX_NR_CLUSTERS * MAX_CPUS_PER_CLUSTER
+
+	.type	mcpm_entry_early_pokes, #object
+ENTRY(mcpm_entry_early_pokes)
+	.space	8 * MAX_NR_CLUSTERS * MAX_CPUS_PER_CLUSTER
+
+	.type	mcpm_power_up_setup_phys, #object
+ENTRY(mcpm_power_up_setup_phys)
+	.space  4		@ set by mcpm_sync_init()

arch/arm/common/mcpm_platsmp.c

@@ -0,0 +1,103 @@
+/*
+ * linux/arch/arm/mach-vexpress/mcpm_platsmp.c
+ *
+ * Created by:  Nicolas Pitre, November 2012
+ * Copyright:   (C) 2012-2013  Linaro Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Code to handle secondary CPU bringup and hotplug for the cluster power API.
+ */
+
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/spinlock.h>
+
+#include <asm/mcpm.h>
+#include <asm/smp.h>
+#include <asm/smp_plat.h>
+
+static void cpu_to_pcpu(unsigned int cpu,
+			unsigned int *pcpu, unsigned int *pcluster)
+{
+	unsigned int mpidr;
+
+	mpidr = cpu_logical_map(cpu);
+	*pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+	*pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+}
+
+static int mcpm_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	unsigned int pcpu, pcluster, ret;
+	extern void secondary_startup(void);
+
+	cpu_to_pcpu(cpu, &pcpu, &pcluster);
+
+	pr_debug("%s: logical CPU %d is physical CPU %d cluster %d\n",
+		 __func__, cpu, pcpu, pcluster);
+
+	mcpm_set_entry_vector(pcpu, pcluster, NULL);
+	ret = mcpm_cpu_power_up(pcpu, pcluster);
+	if (ret)
+		return ret;
+	mcpm_set_entry_vector(pcpu, pcluster, secondary_startup);
+	arch_send_wakeup_ipi_mask(cpumask_of(cpu));
+	dsb_sev();
+	return 0;
+}
+
+static void mcpm_secondary_init(unsigned int cpu)
+{
+	mcpm_cpu_powered_up();
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+static int mcpm_cpu_kill(unsigned int cpu)
+{
+	unsigned int pcpu, pcluster;
+
+	cpu_to_pcpu(cpu, &pcpu, &pcluster);
+
+	return !mcpm_wait_for_cpu_powerdown(pcpu, pcluster);
+}
+
+static int mcpm_cpu_disable(unsigned int cpu)
+{
+	/*
+	 * We assume all CPUs may be shut down.
+	 * This would be the hook to use for eventual Secure
+	 * OS migration requests as described in the PSCI spec.
+	 */
+	return 0;
+}
+
+static void mcpm_cpu_die(unsigned int cpu)
+{
+	unsigned int mpidr, pcpu, pcluster;
+	mpidr = read_cpuid_mpidr();
+	pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+	pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+	mcpm_set_entry_vector(pcpu, pcluster, NULL);
+	mcpm_cpu_power_down();
+}
+
+#endif
+
+static struct smp_operations __initdata mcpm_smp_ops = {
+	.smp_boot_secondary	= mcpm_boot_secondary,
+	.smp_secondary_init	= mcpm_secondary_init,
+#ifdef CONFIG_HOTPLUG_CPU
+	.cpu_kill		= mcpm_cpu_kill,
+	.cpu_disable		= mcpm_cpu_disable,
+	.cpu_die		= mcpm_cpu_die,
+#endif
+};
+
+void __init mcpm_smp_set_ops(void)
+{
+	smp_set_ops(&mcpm_smp_ops);
+}

arch/arm/common/scoop.c

@@ -0,0 +1,275 @@
+/*
+ * Support code for the SCOOP interface found on various Sharp PDAs
+ *
+ * Copyright (c) 2004 Richard Purdie
+ *
+ *	Based on code written by Sharp/Lineo for 2.4 kernels
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/device.h>
+#include <linux/gpio.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/export.h>
+#include <linux/io.h>
+#include <asm/hardware/scoop.h>
+
+/* PCMCIA to Scoop linkage
+
+   There is no easy way to link multiple scoop devices into one
+   single entity for the pxa2xx_pcmcia device so this structure
+   is used which is setup by the platform code.
+
+   This file is never modular so this symbol is always
+   accessile to the board support files.
+*/
+struct scoop_pcmcia_config *platform_scoop_config;
+EXPORT_SYMBOL(platform_scoop_config);
+
+struct  scoop_dev {
+	void __iomem *base;
+	struct gpio_chip gpio;
+	spinlock_t scoop_lock;
+	unsigned short suspend_clr;
+	unsigned short suspend_set;
+	u32 scoop_gpwr;
+};
+
+void reset_scoop(struct device *dev)
+{
+	struct scoop_dev *sdev = dev_get_drvdata(dev);
+
+	iowrite16(0x0100, sdev->base + SCOOP_MCR);  /* 00 */
+	iowrite16(0x0000, sdev->base + SCOOP_CDR);  /* 04 */
+	iowrite16(0x0000, sdev->base + SCOOP_CCR);  /* 10 */
+	iowrite16(0x0000, sdev->base + SCOOP_IMR);  /* 18 */
+	iowrite16(0x00FF, sdev->base + SCOOP_IRM);  /* 14 */
+	iowrite16(0x0000, sdev->base + SCOOP_ISR);  /* 1C */
+	iowrite16(0x0000, sdev->base + SCOOP_IRM);
+}
+
+static void __scoop_gpio_set(struct scoop_dev *sdev,
+			unsigned offset, int value)
+{
+	unsigned short gpwr;
+
+	gpwr = ioread16(sdev->base + SCOOP_GPWR);
+	if (value)
+		gpwr |= 1 << (offset + 1);
+	else
+		gpwr &= ~(1 << (offset + 1));
+	iowrite16(gpwr, sdev->base + SCOOP_GPWR);
+}
+
+static void scoop_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+	struct scoop_dev *sdev = container_of(chip, struct scoop_dev, gpio);
+	unsigned long flags;
+
+	spin_lock_irqsave(&sdev->scoop_lock, flags);
+
+	__scoop_gpio_set(sdev, offset, value);
+
+	spin_unlock_irqrestore(&sdev->scoop_lock, flags);
+}
+
+static int scoop_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+	struct scoop_dev *sdev = container_of(chip, struct scoop_dev, gpio);
+
+	/* XXX: I'm unsure, but it seems so */
+	return ioread16(sdev->base + SCOOP_GPRR) & (1 << (offset + 1));
+}
+
+static int scoop_gpio_direction_input(struct gpio_chip *chip,
+			unsigned offset)
+{
+	struct scoop_dev *sdev = container_of(chip, struct scoop_dev, gpio);
+	unsigned long flags;
+	unsigned short gpcr;
+
+	spin_lock_irqsave(&sdev->scoop_lock, flags);
+
+	gpcr = ioread16(sdev->base + SCOOP_GPCR);
+	gpcr &= ~(1 << (offset + 1));
+	iowrite16(gpcr, sdev->base + SCOOP_GPCR);
+
+	spin_unlock_irqrestore(&sdev->scoop_lock, flags);
+
+	return 0;
+}
+
+static int scoop_gpio_direction_output(struct gpio_chip *chip,
+			unsigned offset, int value)
+{
+	struct scoop_dev *sdev = container_of(chip, struct scoop_dev, gpio);
+	unsigned long flags;
+	unsigned short gpcr;
+
+	spin_lock_irqsave(&sdev->scoop_lock, flags);
+
+	__scoop_gpio_set(sdev, offset, value);
+
+	gpcr = ioread16(sdev->base + SCOOP_GPCR);
+	gpcr |= 1 << (offset + 1);
+	iowrite16(gpcr, sdev->base + SCOOP_GPCR);
+
+	spin_unlock_irqrestore(&sdev->scoop_lock, flags);
+
+	return 0;
+}
+
+unsigned short read_scoop_reg(struct device *dev, unsigned short reg)
+{
+	struct scoop_dev *sdev = dev_get_drvdata(dev);
+	return ioread16(sdev->base + reg);
+}
+
+void write_scoop_reg(struct device *dev, unsigned short reg, unsigned short data)
+{
+	struct scoop_dev *sdev = dev_get_drvdata(dev);
+	iowrite16(data, sdev->base + reg);
+}
+
+EXPORT_SYMBOL(reset_scoop);
+EXPORT_SYMBOL(read_scoop_reg);
+EXPORT_SYMBOL(write_scoop_reg);
+
+#ifdef CONFIG_PM
+static void check_scoop_reg(struct scoop_dev *sdev)
+{
+	unsigned short mcr;
+
+	mcr = ioread16(sdev->base + SCOOP_MCR);
+	if ((mcr & 0x100) == 0)
+		iowrite16(0x0101, sdev->base + SCOOP_MCR);
+}
+
+static int scoop_suspend(struct platform_device *dev, pm_message_t state)
+{
+	struct scoop_dev *sdev = platform_get_drvdata(dev);
+
+	check_scoop_reg(sdev);
+	sdev->scoop_gpwr = ioread16(sdev->base + SCOOP_GPWR);
+	iowrite16((sdev->scoop_gpwr & ~sdev->suspend_clr) | sdev->suspend_set, sdev->base + SCOOP_GPWR);
+
+	return 0;
+}
+
+static int scoop_resume(struct platform_device *dev)
+{
+	struct scoop_dev *sdev = platform_get_drvdata(dev);
+
+	check_scoop_reg(sdev);
+	iowrite16(sdev->scoop_gpwr, sdev->base + SCOOP_GPWR);
+
+	return 0;
+}
+#else
+#define scoop_suspend	NULL
+#define scoop_resume	NULL
+#endif
+
+static int scoop_probe(struct platform_device *pdev)
+{
+	struct scoop_dev *devptr;
+	struct scoop_config *inf;
+	struct resource *mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	int ret;
+
+	if (!mem)
+		return -EINVAL;
+
+	devptr = kzalloc(sizeof(struct scoop_dev), GFP_KERNEL);
+	if (!devptr)
+		return -ENOMEM;
+
+	spin_lock_init(&devptr->scoop_lock);
+
+	inf = pdev->dev.platform_data;
+	devptr->base = ioremap(mem->start, resource_size(mem));
+
+	if (!devptr->base) {
+		ret = -ENOMEM;
+		goto err_ioremap;
+	}
+
+	platform_set_drvdata(pdev, devptr);
+
+	printk("Sharp Scoop Device found at 0x%08x -> 0x%8p\n",(unsigned int)mem->start, devptr->base);
+
+	iowrite16(0x0140, devptr->base + SCOOP_MCR);
+	reset_scoop(&pdev->dev);
+	iowrite16(0x0000, devptr->base + SCOOP_CPR);
+	iowrite16(inf->io_dir & 0xffff, devptr->base + SCOOP_GPCR);
+	iowrite16(inf->io_out & 0xffff, devptr->base + SCOOP_GPWR);
+
+	devptr->suspend_clr = inf->suspend_clr;
+	devptr->suspend_set = inf->suspend_set;
+
+	devptr->gpio.base = -1;
+
+	if (inf->gpio_base != 0) {
+		devptr->gpio.label = dev_name(&pdev->dev);
+		devptr->gpio.base = inf->gpio_base;
+		devptr->gpio.ngpio = 12; /* PA11 = 0, PA12 = 1, etc. up to PA22 = 11 */
+		devptr->gpio.set = scoop_gpio_set;
+		devptr->gpio.get = scoop_gpio_get;
+		devptr->gpio.direction_input = scoop_gpio_direction_input;
+		devptr->gpio.direction_output = scoop_gpio_direction_output;
+
+		ret = gpiochip_add(&devptr->gpio);
+		if (ret)
+			goto err_gpio;
+	}
+
+	return 0;
+
+err_gpio:
+	platform_set_drvdata(pdev, NULL);
+err_ioremap:
+	iounmap(devptr->base);
+	kfree(devptr);
+
+	return ret;
+}
+
+static int scoop_remove(struct platform_device *pdev)
+{
+	struct scoop_dev *sdev = platform_get_drvdata(pdev);
+
+	if (!sdev)
+		return -EINVAL;
+
+	if (sdev->gpio.base != -1)
+		gpiochip_remove(&sdev->gpio);
+
+	platform_set_drvdata(pdev, NULL);
+	iounmap(sdev->base);
+	kfree(sdev);
+
+	return 0;
+}
+
+static struct platform_driver scoop_driver = {
+	.probe		= scoop_probe,
+	.remove		= scoop_remove,
+	.suspend	= scoop_suspend,
+	.resume		= scoop_resume,
+	.driver		= {
+		.name	= "sharp-scoop",
+	},
+};
+
+static int __init scoop_init(void)
+{
+	return platform_driver_register(&scoop_driver);
+}
+
+subsys_initcall(scoop_init);

arch/arm/common/sharpsl_param.c

@@ -0,0 +1,65 @@
+/*
+ * Hardware parameter area specific to Sharp SL series devices
+ *
+ * Copyright (c) 2005 Richard Purdie
+ *
+ * Based on Sharp's 2.4 kernel patches
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <asm/mach/sharpsl_param.h>
+#include <asm/memory.h>
+
+/*
+ * Certain hardware parameters determined at the time of device manufacture,
+ * typically including LCD parameters are loaded by the bootloader at the
+ * address PARAM_BASE. As the kernel will overwrite them, we need to store
+ * them early in the boot process, then pass them to the appropriate drivers.
+ * Not all devices use all parameters but the format is common to all.
+ */
+#ifdef CONFIG_ARCH_SA1100
+#define PARAM_BASE	0xe8ffc000
+#define param_start(x)	(void *)(x)
+#else
+#define PARAM_BASE	0xa0000a00
+#define param_start(x)	__va(x)
+#endif
+#define MAGIC_CHG(a,b,c,d) ( ( d << 24 ) | ( c << 16 )  | ( b << 8 ) | a )
+
+#define COMADJ_MAGIC	MAGIC_CHG('C','M','A','D')
+#define UUID_MAGIC	MAGIC_CHG('U','U','I','D')
+#define TOUCH_MAGIC	MAGIC_CHG('T','U','C','H')
+#define AD_MAGIC	MAGIC_CHG('B','V','A','D')
+#define PHAD_MAGIC	MAGIC_CHG('P','H','A','D')
+
+struct sharpsl_param_info sharpsl_param;
+EXPORT_SYMBOL(sharpsl_param);
+
+void sharpsl_save_param(void)
+{
+	memcpy(&sharpsl_param, param_start(PARAM_BASE), sizeof(struct sharpsl_param_info));
+
+	if (sharpsl_param.comadj_keyword != COMADJ_MAGIC)
+		sharpsl_param.comadj=-1;
+
+	if (sharpsl_param.phad_keyword != PHAD_MAGIC)
+		sharpsl_param.phadadj=-1;
+
+	if (sharpsl_param.uuid_keyword != UUID_MAGIC)
+		sharpsl_param.uuid[0]=-1;
+
+	if (sharpsl_param.touch_keyword != TOUCH_MAGIC)
+		sharpsl_param.touch_xp=-1;
+
+	if (sharpsl_param.adadj_keyword != AD_MAGIC)
+		sharpsl_param.adadj=-1;
+}
+
+

arch/arm/common/timer-sp.c

@@ -0,0 +1,304 @@
+/*
+ *  linux/arch/arm/common/timer-sp.c
+ *
+ *  Copyright (C) 1999 - 2003 ARM Limited
+ *  Copyright (C) 2000 Deep Blue Solutions Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#include <linux/clk.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+#include <asm/hardware/arm_timer.h>
+#include <asm/hardware/timer-sp.h>
+
+static long __init sp804_get_clock_rate(struct clk *clk)
+{
+	long rate;
+	int err;
+
+	err = clk_prepare(clk);
+	if (err) {
+		pr_err("sp804: clock failed to prepare: %d\n", err);
+		clk_put(clk);
+		return err;
+	}
+
+	err = clk_enable(clk);
+	if (err) {
+		pr_err("sp804: clock failed to enable: %d\n", err);
+		clk_unprepare(clk);
+		clk_put(clk);
+		return err;
+	}
+
+	rate = clk_get_rate(clk);
+	if (rate < 0) {
+		pr_err("sp804: clock failed to get rate: %ld\n", rate);
+		clk_disable(clk);
+		clk_unprepare(clk);
+		clk_put(clk);
+	}
+
+	return rate;
+}
+
+static void __iomem *sched_clock_base;
+
+static u64 notrace sp804_read(void)
+{
+	return ~readl_relaxed(sched_clock_base + TIMER_VALUE);
+}
+
+void __init __sp804_clocksource_and_sched_clock_init(void __iomem *base,
+						     const char *name,
+						     struct clk *clk,
+						     int use_sched_clock)
+{
+	long rate;
+
+	if (!clk) {
+		clk = clk_get_sys("sp804", name);
+		if (IS_ERR(clk)) {
+			pr_err("sp804: clock not found: %d\n",
+			       (int)PTR_ERR(clk));
+			return;
+		}
+	}
+
+	rate = sp804_get_clock_rate(clk);
+
+	if (rate < 0)
+		return;
+
+	/* setup timer 0 as free-running clocksource */
+	writel(0, base + TIMER_CTRL);
+	writel(0xffffffff, base + TIMER_LOAD);
+	writel(0xffffffff, base + TIMER_VALUE);
+	writel(TIMER_CTRL_32BIT | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC,
+		base + TIMER_CTRL);
+
+	clocksource_mmio_init(base + TIMER_VALUE, name,
+		rate, 200, 32, clocksource_mmio_readl_down);
+
+	if (use_sched_clock) {
+		sched_clock_base = base;
+		sched_clock_register(sp804_read, 32, rate);
+	}
+}
+
+
+static void __iomem *clkevt_base;
+static unsigned long clkevt_reload;
+
+/*
+ * IRQ handler for the timer
+ */
+static irqreturn_t sp804_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	/* clear the interrupt */
+	writel(1, clkevt_base + TIMER_INTCLR);
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static void sp804_set_mode(enum clock_event_mode mode,
+	struct clock_event_device *evt)
+{
+	unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE;
+
+	writel(ctrl, clkevt_base + TIMER_CTRL);
+
+	switch (mode) {
+	case CLOCK_EVT_MODE_PERIODIC:
+		writel(clkevt_reload, clkevt_base + TIMER_LOAD);
+		ctrl |= TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;
+		break;
+
+	case CLOCK_EVT_MODE_ONESHOT:
+		/* period set, and timer enabled in 'next_event' hook */
+		ctrl |= TIMER_CTRL_ONESHOT;
+		break;
+
+	case CLOCK_EVT_MODE_UNUSED:
+	case CLOCK_EVT_MODE_SHUTDOWN:
+	default:
+		break;
+	}
+
+	writel(ctrl, clkevt_base + TIMER_CTRL);
+}
+
+static int sp804_set_next_event(unsigned long next,
+	struct clock_event_device *evt)
+{
+	unsigned long ctrl = readl(clkevt_base + TIMER_CTRL);
+
+	writel(next, clkevt_base + TIMER_LOAD);
+	writel(ctrl | TIMER_CTRL_ENABLE, clkevt_base + TIMER_CTRL);
+
+	return 0;
+}
+
+static struct clock_event_device sp804_clockevent = {
+	.features       = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
+		CLOCK_EVT_FEAT_DYNIRQ,
+	.set_mode	= sp804_set_mode,
+	.set_next_event	= sp804_set_next_event,
+	.rating		= 300,
+};
+
+static struct irqaction sp804_timer_irq = {
+	.name		= "timer",
+	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= sp804_timer_interrupt,
+	.dev_id		= &sp804_clockevent,
+};
+
+void __init __sp804_clockevents_init(void __iomem *base, unsigned int irq, struct clk *clk, const char *name)
+{
+	struct clock_event_device *evt = &sp804_clockevent;
+	long rate;
+
+	if (!clk)
+		clk = clk_get_sys("sp804", name);
+	if (IS_ERR(clk)) {
+		pr_err("sp804: %s clock not found: %d\n", name,
+			(int)PTR_ERR(clk));
+		return;
+	}
+
+	rate = sp804_get_clock_rate(clk);
+	if (rate < 0)
+		return;
+
+	clkevt_base = base;
+	clkevt_reload = DIV_ROUND_CLOSEST(rate, HZ);
+	evt->name = name;
+	evt->irq = irq;
+	evt->cpumask = cpu_possible_mask;
+
+	writel(0, base + TIMER_CTRL);
+
+	setup_irq(irq, &sp804_timer_irq);
+	clockevents_config_and_register(evt, rate, 0xf, 0xffffffff);
+}
+
+static void __init sp804_of_init(struct device_node *np)
+{
+	static bool initialized = false;
+	void __iomem *base;
+	int irq;
+	u32 irq_num = 0;
+	struct clk *clk1, *clk2;
+	const char *name = of_get_property(np, "compatible", NULL);
+
+	base = of_iomap(np, 0);
+	if (WARN_ON(!base))
+		return;
+
+	/* Ensure timers are disabled */
+	writel(0, base + TIMER_CTRL);
+	writel(0, base + TIMER_2_BASE + TIMER_CTRL);
+
+	if (initialized || !of_device_is_available(np))
+		goto err;
+
+	clk1 = of_clk_get(np, 0);
+	if (IS_ERR(clk1))
+		clk1 = NULL;
+
+	/* Get the 2nd clock if the timer has 3 timer clocks */
+	if (of_count_phandle_with_args(np, "clocks", "#clock-cells") == 3) {
+		clk2 = of_clk_get(np, 1);
+		if (IS_ERR(clk2)) {
+			pr_err("sp804: %s clock not found: %d\n", np->name,
+				(int)PTR_ERR(clk2));
+			clk2 = NULL;
+		}
+	} else
+		clk2 = clk1;
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq <= 0)
+		goto err;
+
+	of_property_read_u32(np, "arm,sp804-has-irq", &irq_num);
+	if (irq_num == 2) {
+		__sp804_clockevents_init(base + TIMER_2_BASE, irq, clk2, name);
+		__sp804_clocksource_and_sched_clock_init(base, name, clk1, 1);
+	} else {
+		__sp804_clockevents_init(base, irq, clk1 , name);
+		__sp804_clocksource_and_sched_clock_init(base + TIMER_2_BASE,
+							 name, clk2, 1);
+	}
+	initialized = true;
+
+	return;
+err:
+	iounmap(base);
+}
+CLOCKSOURCE_OF_DECLARE(sp804, "arm,sp804", sp804_of_init);
+
+static void __init integrator_cp_of_init(struct device_node *np)
+{
+	static int init_count = 0;
+	void __iomem *base;
+	int irq;
+	const char *name = of_get_property(np, "compatible", NULL);
+	struct clk *clk;
+
+	base = of_iomap(np, 0);
+	if (WARN_ON(!base))
+		return;
+	clk = of_clk_get(np, 0);
+	if (WARN_ON(IS_ERR(clk)))
+		return;
+
+	/* Ensure timer is disabled */
+	writel(0, base + TIMER_CTRL);
+
+	if (init_count == 2 || !of_device_is_available(np))
+		goto err;
+
+	if (!init_count)
+		__sp804_clocksource_and_sched_clock_init(base, name, clk, 0);
+	else {
+		irq = irq_of_parse_and_map(np, 0);
+		if (irq <= 0)
+			goto err;
+
+		__sp804_clockevents_init(base, irq, clk, name);
+	}
+
+	init_count++;
+	return;
+err:
+	iounmap(base);
+}
+CLOCKSOURCE_OF_DECLARE(intcp, "arm,integrator-cp-timer", integrator_cp_of_init);

arch/arm/common/vlock.S

@@ -0,0 +1,108 @@
+/*
+ * vlock.S - simple voting lock implementation for ARM
+ *
+ * Created by:	Dave Martin, 2012-08-16
+ * Copyright:	(C) 2012-2013  Linaro Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ *
+ * This algorithm is described in more detail in
+ * Documentation/arm/vlocks.txt.
+ */
+
+#include <linux/linkage.h>
+#include "vlock.h"
+
+/* Select different code if voting flags  can fit in a single word. */
+#if VLOCK_VOTING_SIZE > 4
+#define FEW(x...)
+#define MANY(x...) x
+#else
+#define FEW(x...) x
+#define MANY(x...)
+#endif
+
+@ voting lock for first-man coordination
+
+.macro voting_begin rbase:req, rcpu:req, rscratch:req
+	mov	\rscratch, #1
+	strb	\rscratch, [\rbase, \rcpu]
+	dmb
+.endm
+
+.macro voting_end rbase:req, rcpu:req, rscratch:req
+	dmb
+	mov	\rscratch, #0
+	strb	\rscratch, [\rbase, \rcpu]
+	dsb	st
+	sev
+.endm
+
+/*
+ * The vlock structure must reside in Strongly-Ordered or Device memory.
+ * This implementation deliberately eliminates most of the barriers which
+ * would be required for other memory types, and assumes that independent
+ * writes to neighbouring locations within a cacheline do not interfere
+ * with one another.
+ */
+
+@ r0: lock structure base
+@ r1: CPU ID (0-based index within cluster)
+ENTRY(vlock_trylock)
+	add	r1, r1, #VLOCK_VOTING_OFFSET
+
+	voting_begin	r0, r1, r2
+
+	ldrb	r2, [r0, #VLOCK_OWNER_OFFSET]	@ check whether lock is held
+	cmp	r2, #VLOCK_OWNER_NONE
+	bne	trylock_fail			@ fail if so
+
+	@ Control dependency implies strb not observable before previous ldrb.
+
+	strb	r1, [r0, #VLOCK_OWNER_OFFSET]	@ submit my vote
+
+	voting_end	r0, r1, r2		@ implies DMB
+
+	@ Wait for the current round of voting to finish:
+
+ MANY(	mov	r3, #VLOCK_VOTING_OFFSET			)
+0:
+ MANY(	ldr	r2, [r0, r3]					)
+ FEW(	ldr	r2, [r0, #VLOCK_VOTING_OFFSET]			)
+	cmp	r2, #0
+	wfene
+	bne	0b
+ MANY(	add	r3, r3, #4					)
+ MANY(	cmp	r3, #VLOCK_VOTING_OFFSET + VLOCK_VOTING_SIZE	)
+ MANY(	bne	0b						)
+
+	@ Check who won:
+
+	dmb
+	ldrb	r2, [r0, #VLOCK_OWNER_OFFSET]
+	eor	r0, r1, r2			@ zero if I won, else nonzero
+	bx	lr
+
+trylock_fail:
+	voting_end	r0, r1, r2
+	mov	r0, #1				@ nonzero indicates that I lost
+	bx	lr
+ENDPROC(vlock_trylock)
+
+@ r0: lock structure base
+ENTRY(vlock_unlock)
+	dmb
+	mov	r1, #VLOCK_OWNER_NONE
+	strb	r1, [r0, #VLOCK_OWNER_OFFSET]
+	dsb	st
+	sev
+	bx	lr
+ENDPROC(vlock_unlock)

arch/arm/common/vlock.h

@@ -0,0 +1,29 @@
+/*
+ * vlock.h - simple voting lock implementation
+ *
+ * Created by:	Dave Martin, 2012-08-16
+ * Copyright:	(C) 2012-2013  Linaro Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __VLOCK_H
+#define __VLOCK_H
+
+#include <asm/mcpm.h>
+
+/* Offsets and sizes are rounded to a word (4 bytes) */
+#define VLOCK_OWNER_OFFSET	0
+#define VLOCK_VOTING_OFFSET	4
+#define VLOCK_VOTING_SIZE	((MAX_CPUS_PER_CLUSTER + 3) / 4 * 4)
+#define VLOCK_SIZE		(VLOCK_VOTING_OFFSET + VLOCK_VOTING_SIZE)
+#define VLOCK_OWNER_NONE	0
+
+#endif /* ! __VLOCK_H */