Fixed MTP to work with TWRP

drivers/misc/cxl/Kconfig

@@ -0,0 +1,25 @@
+#
+# IBM Coherent Accelerator (CXL) compatible devices
+#
+
+config CXL_BASE
+	bool
+	default n
+	select PPC_COPRO_BASE
+
+config CXL
+	tristate "Support for IBM Coherent Accelerators (CXL)"
+	depends on PPC_POWERNV && PCI_MSI
+	select CXL_BASE
+	default m
+	help
+	  Select this option to enable driver support for IBM Coherent
+	  Accelerators (CXL).  CXL is otherwise known as Coherent Accelerator
+	  Processor Interface (CAPI).  CAPI allows accelerators in FPGAs to be
+	  coherently attached to a CPU via an MMU.  This driver enables
+	  userspace programs to access these accelerators via /dev/cxl/afuM.N
+	  devices.
+
+	  CAPI adapters are found in POWER8 based systems.
+
+	  If unsure, say N.

drivers/misc/cxl/Makefile

@@ -0,0 +1,3 @@
+cxl-y				+= main.o file.o irq.o fault.o native.o context.o sysfs.o debugfs.o pci.o
+obj-$(CONFIG_CXL)		+= cxl.o
+obj-$(CONFIG_CXL_BASE)		+= base.o

drivers/misc/cxl/base.c

@@ -0,0 +1,86 @@
+/*
+ * Copyright 2014 IBM Corp.
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/rcupdate.h>
+#include <asm/errno.h>
+#include <misc/cxl.h>
+#include "cxl.h"
+
+/* protected by rcu */
+static struct cxl_calls *cxl_calls;
+
+atomic_t cxl_use_count = ATOMIC_INIT(0);
+EXPORT_SYMBOL(cxl_use_count);
+
+#ifdef CONFIG_CXL_MODULE
+
+static inline struct cxl_calls *cxl_calls_get(void)
+{
+	struct cxl_calls *calls = NULL;
+
+	rcu_read_lock();
+	calls = rcu_dereference(cxl_calls);
+	if (calls && !try_module_get(calls->owner))
+		calls = NULL;
+	rcu_read_unlock();
+
+	return calls;
+}
+
+static inline void cxl_calls_put(struct cxl_calls *calls)
+{
+	BUG_ON(calls != cxl_calls);
+
+	/* we don't need to rcu this, as we hold a reference to the module */
+	module_put(cxl_calls->owner);
+}
+
+#else /* !defined CONFIG_CXL_MODULE */
+
+static inline struct cxl_calls *cxl_calls_get(void)
+{
+	return cxl_calls;
+}
+
+static inline void cxl_calls_put(struct cxl_calls *calls) { }
+
+#endif /* CONFIG_CXL_MODULE */
+
+void cxl_slbia(struct mm_struct *mm)
+{
+	struct cxl_calls *calls;
+
+	calls = cxl_calls_get();
+	if (!calls)
+		return;
+
+	if (cxl_ctx_in_use())
+	    calls->cxl_slbia(mm);
+
+	cxl_calls_put(calls);
+}
+
+int register_cxl_calls(struct cxl_calls *calls)
+{
+	if (cxl_calls)
+		return -EBUSY;
+
+	rcu_assign_pointer(cxl_calls, calls);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(register_cxl_calls);
+
+void unregister_cxl_calls(struct cxl_calls *calls)
+{
+	BUG_ON(cxl_calls->owner != calls->owner);
+	RCU_INIT_POINTER(cxl_calls, NULL);
+	synchronize_rcu();
+}
+EXPORT_SYMBOL_GPL(unregister_cxl_calls);

drivers/misc/cxl/context.c

@@ -0,0 +1,203 @@
+/*
+ * Copyright 2014 IBM Corp.
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/bitmap.h>
+#include <linux/sched.h>
+#include <linux/pid.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/debugfs.h>
+#include <linux/slab.h>
+#include <linux/idr.h>
+#include <asm/cputable.h>
+#include <asm/current.h>
+#include <asm/copro.h>
+
+#include "cxl.h"
+
+/*
+ * Allocates space for a CXL context.
+ */
+struct cxl_context *cxl_context_alloc(void)
+{
+	return kzalloc(sizeof(struct cxl_context), GFP_KERNEL);
+}
+
+/*
+ * Initialises a CXL context.
+ */
+int cxl_context_init(struct cxl_context *ctx, struct cxl_afu *afu, bool master,
+		     struct address_space *mapping)
+{
+	int i;
+
+	spin_lock_init(&ctx->sste_lock);
+	ctx->afu = afu;
+	ctx->master = master;
+	ctx->pid = NULL; /* Set in start work ioctl */
+	mutex_init(&ctx->mapping_lock);
+	ctx->mapping = mapping;
+
+	/*
+	 * Allocate the segment table before we put it in the IDR so that we
+	 * can always access it when dereferenced from IDR. For the same
+	 * reason, the segment table is only destroyed after the context is
+	 * removed from the IDR.  Access to this in the IOCTL is protected by
+	 * Linux filesytem symantics (can't IOCTL until open is complete).
+	 */
+	i = cxl_alloc_sst(ctx);
+	if (i)
+		return i;
+
+	INIT_WORK(&ctx->fault_work, cxl_handle_fault);
+
+	init_waitqueue_head(&ctx->wq);
+	spin_lock_init(&ctx->lock);
+
+	ctx->irq_bitmap = NULL;
+	ctx->pending_irq = false;
+	ctx->pending_fault = false;
+	ctx->pending_afu_err = false;
+
+	/*
+	 * When we have to destroy all contexts in cxl_context_detach_all() we
+	 * end up with afu_release_irqs() called from inside a
+	 * idr_for_each_entry(). Hence we need to make sure that anything
+	 * dereferenced from this IDR is ok before we allocate the IDR here.
+	 * This clears out the IRQ ranges to ensure this.
+	 */
+	for (i = 0; i < CXL_IRQ_RANGES; i++)
+		ctx->irqs.range[i] = 0;
+
+	mutex_init(&ctx->status_mutex);
+
+	ctx->status = OPENED;
+
+	/*
+	 * Allocating IDR! We better make sure everything's setup that
+	 * dereferences from it.
+	 */
+	mutex_lock(&afu->contexts_lock);
+	idr_preload(GFP_KERNEL);
+	i = idr_alloc(&ctx->afu->contexts_idr, ctx, 0,
+		      ctx->afu->num_procs, GFP_NOWAIT);
+	idr_preload_end();
+	mutex_unlock(&afu->contexts_lock);
+	if (i < 0)
+		return i;
+
+	ctx->pe = i;
+	ctx->elem = &ctx->afu->spa[i];
+	ctx->pe_inserted = false;
+	return 0;
+}
+
+/*
+ * Map a per-context mmio space into the given vma.
+ */
+int cxl_context_iomap(struct cxl_context *ctx, struct vm_area_struct *vma)
+{
+	u64 len = vma->vm_end - vma->vm_start;
+	len = min(len, ctx->psn_size);
+
+	if (ctx->afu->current_mode == CXL_MODE_DEDICATED) {
+		vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+		return vm_iomap_memory(vma, ctx->afu->psn_phys, ctx->afu->adapter->ps_size);
+	}
+
+	/* make sure there is a valid per process space for this AFU */
+	if ((ctx->master && !ctx->afu->psa) || (!ctx->afu->pp_psa)) {
+		pr_devel("AFU doesn't support mmio space\n");
+		return -EINVAL;
+	}
+
+	/* Can't mmap until the AFU is enabled */
+	if (!ctx->afu->enabled)
+		return -EBUSY;
+
+	pr_devel("%s: mmio physical: %llx pe: %i master:%i\n", __func__,
+		 ctx->psn_phys, ctx->pe , ctx->master);
+
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+	return vm_iomap_memory(vma, ctx->psn_phys, len);
+}
+
+/*
+ * Detach a context from the hardware. This disables interrupts and doesn't
+ * return until all outstanding interrupts for this context have completed. The
+ * hardware should no longer access *ctx after this has returned.
+ */
+static void __detach_context(struct cxl_context *ctx)
+{
+	enum cxl_context_status status;
+
+	mutex_lock(&ctx->status_mutex);
+	status = ctx->status;
+	ctx->status = CLOSED;
+	mutex_unlock(&ctx->status_mutex);
+	if (status != STARTED)
+		return;
+
+	WARN_ON(cxl_detach_process(ctx));
+	afu_release_irqs(ctx);
+	flush_work(&ctx->fault_work); /* Only needed for dedicated process */
+	wake_up_all(&ctx->wq);
+
+	/* Release Problem State Area mapping */
+	mutex_lock(&ctx->mapping_lock);
+	if (ctx->mapping)
+		unmap_mapping_range(ctx->mapping, 0, 0, 1);
+	mutex_unlock(&ctx->mapping_lock);
+}
+
+/*
+ * Detach the given context from the AFU. This doesn't actually
+ * free the context but it should stop the context running in hardware
+ * (ie. prevent this context from generating any further interrupts
+ * so that it can be freed).
+ */
+void cxl_context_detach(struct cxl_context *ctx)
+{
+	__detach_context(ctx);
+}
+
+/*
+ * Detach all contexts on the given AFU.
+ */
+void cxl_context_detach_all(struct cxl_afu *afu)
+{
+	struct cxl_context *ctx;
+	int tmp;
+
+	mutex_lock(&afu->contexts_lock);
+	idr_for_each_entry(&afu->contexts_idr, ctx, tmp) {
+		/*
+		 * Anything done in here needs to be setup before the IDR is
+		 * created and torn down after the IDR removed
+		 */
+		__detach_context(ctx);
+	}
+	mutex_unlock(&afu->contexts_lock);
+}
+
+void cxl_context_free(struct cxl_context *ctx)
+{
+	mutex_lock(&ctx->afu->contexts_lock);
+	idr_remove(&ctx->afu->contexts_idr, ctx->pe);
+	mutex_unlock(&ctx->afu->contexts_lock);
+	synchronize_rcu();
+
+	free_page((u64)ctx->sstp);
+	ctx->sstp = NULL;
+
+	put_pid(ctx->pid);
+	kfree(ctx);
+}

drivers/misc/cxl/cxl.h

@@ -0,0 +1,635 @@
+/*
+ * Copyright 2014 IBM Corp.
+ *
+ * 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.
+ */
+
+#ifndef _CXL_H_
+#define _CXL_H_
+
+#include <linux/interrupt.h>
+#include <linux/semaphore.h>
+#include <linux/device.h>
+#include <linux/types.h>
+#include <linux/cdev.h>
+#include <linux/pid.h>
+#include <linux/io.h>
+#include <linux/pci.h>
+#include <asm/cputable.h>
+#include <asm/mmu.h>
+#include <asm/reg.h>
+#include <misc/cxl.h>
+
+#include <uapi/misc/cxl.h>
+
+extern uint cxl_verbose;
+
+#define CXL_TIMEOUT 5
+
+/*
+ * Bump version each time a user API change is made, whether it is
+ * backwards compatible ot not.
+ */
+#define CXL_API_VERSION 1
+#define CXL_API_VERSION_COMPATIBLE 1
+
+/*
+ * Opaque types to avoid accidentally passing registers for the wrong MMIO
+ *
+ * At the end of the day, I'm not married to using typedef here, but it might
+ * (and has!) help avoid bugs like mixing up CXL_PSL_CtxTime and
+ * CXL_PSL_CtxTime_An, or calling cxl_p1n_write instead of cxl_p1_write.
+ *
+ * I'm quite happy if these are changed back to #defines before upstreaming, it
+ * should be little more than a regexp search+replace operation in this file.
+ */
+typedef struct {
+	const int x;
+} cxl_p1_reg_t;
+typedef struct {
+	const int x;
+} cxl_p1n_reg_t;
+typedef struct {
+	const int x;
+} cxl_p2n_reg_t;
+#define cxl_reg_off(reg) \
+	(reg.x)
+
+/* Memory maps. Ref CXL Appendix A */
+
+/* PSL Privilege 1 Memory Map */
+/* Configuration and Control area */
+static const cxl_p1_reg_t CXL_PSL_CtxTime = {0x0000};
+static const cxl_p1_reg_t CXL_PSL_ErrIVTE = {0x0008};
+static const cxl_p1_reg_t CXL_PSL_KEY1    = {0x0010};
+static const cxl_p1_reg_t CXL_PSL_KEY2    = {0x0018};
+static const cxl_p1_reg_t CXL_PSL_Control = {0x0020};
+/* Downloading */
+static const cxl_p1_reg_t CXL_PSL_DLCNTL  = {0x0060};
+static const cxl_p1_reg_t CXL_PSL_DLADDR  = {0x0068};
+
+/* PSL Lookaside Buffer Management Area */
+static const cxl_p1_reg_t CXL_PSL_LBISEL  = {0x0080};
+static const cxl_p1_reg_t CXL_PSL_SLBIE   = {0x0088};
+static const cxl_p1_reg_t CXL_PSL_SLBIA   = {0x0090};
+static const cxl_p1_reg_t CXL_PSL_TLBIE   = {0x00A0};
+static const cxl_p1_reg_t CXL_PSL_TLBIA   = {0x00A8};
+static const cxl_p1_reg_t CXL_PSL_AFUSEL  = {0x00B0};
+
+/* 0x00C0:7EFF Implementation dependent area */
+static const cxl_p1_reg_t CXL_PSL_FIR1      = {0x0100};
+static const cxl_p1_reg_t CXL_PSL_FIR2      = {0x0108};
+static const cxl_p1_reg_t CXL_PSL_VERSION   = {0x0118};
+static const cxl_p1_reg_t CXL_PSL_RESLCKTO  = {0x0128};
+static const cxl_p1_reg_t CXL_PSL_FIR_CNTL  = {0x0148};
+static const cxl_p1_reg_t CXL_PSL_DSNDCTL   = {0x0150};
+static const cxl_p1_reg_t CXL_PSL_SNWRALLOC = {0x0158};
+static const cxl_p1_reg_t CXL_PSL_TRACE     = {0x0170};
+/* 0x7F00:7FFF Reserved PCIe MSI-X Pending Bit Array area */
+/* 0x8000:FFFF Reserved PCIe MSI-X Table Area */
+
+/* PSL Slice Privilege 1 Memory Map */
+/* Configuration Area */
+static const cxl_p1n_reg_t CXL_PSL_SR_An          = {0x00};
+static const cxl_p1n_reg_t CXL_PSL_LPID_An        = {0x08};
+static const cxl_p1n_reg_t CXL_PSL_AMBAR_An       = {0x10};
+static const cxl_p1n_reg_t CXL_PSL_SPOffset_An    = {0x18};
+static const cxl_p1n_reg_t CXL_PSL_ID_An          = {0x20};
+static const cxl_p1n_reg_t CXL_PSL_SERR_An        = {0x28};
+/* Memory Management and Lookaside Buffer Management */
+static const cxl_p1n_reg_t CXL_PSL_SDR_An         = {0x30};
+static const cxl_p1n_reg_t CXL_PSL_AMOR_An        = {0x38};
+/* Pointer Area */
+static const cxl_p1n_reg_t CXL_HAURP_An           = {0x80};
+static const cxl_p1n_reg_t CXL_PSL_SPAP_An        = {0x88};
+static const cxl_p1n_reg_t CXL_PSL_LLCMD_An       = {0x90};
+/* Control Area */
+static const cxl_p1n_reg_t CXL_PSL_SCNTL_An       = {0xA0};
+static const cxl_p1n_reg_t CXL_PSL_CtxTime_An     = {0xA8};
+static const cxl_p1n_reg_t CXL_PSL_IVTE_Offset_An = {0xB0};
+static const cxl_p1n_reg_t CXL_PSL_IVTE_Limit_An  = {0xB8};
+/* 0xC0:FF Implementation Dependent Area */
+static const cxl_p1n_reg_t CXL_PSL_FIR_SLICE_An   = {0xC0};
+static const cxl_p1n_reg_t CXL_AFU_DEBUG_An       = {0xC8};
+static const cxl_p1n_reg_t CXL_PSL_APCALLOC_A     = {0xD0};
+static const cxl_p1n_reg_t CXL_PSL_COALLOC_A      = {0xD8};
+static const cxl_p1n_reg_t CXL_PSL_RXCTL_A        = {0xE0};
+static const cxl_p1n_reg_t CXL_PSL_SLICE_TRACE    = {0xE8};
+
+/* PSL Slice Privilege 2 Memory Map */
+/* Configuration and Control Area */
+static const cxl_p2n_reg_t CXL_PSL_PID_TID_An = {0x000};
+static const cxl_p2n_reg_t CXL_CSRP_An        = {0x008};
+static const cxl_p2n_reg_t CXL_AURP0_An       = {0x010};
+static const cxl_p2n_reg_t CXL_AURP1_An       = {0x018};
+static const cxl_p2n_reg_t CXL_SSTP0_An       = {0x020};
+static const cxl_p2n_reg_t CXL_SSTP1_An       = {0x028};
+static const cxl_p2n_reg_t CXL_PSL_AMR_An     = {0x030};
+/* Segment Lookaside Buffer Management */
+static const cxl_p2n_reg_t CXL_SLBIE_An       = {0x040};
+static const cxl_p2n_reg_t CXL_SLBIA_An       = {0x048};
+static const cxl_p2n_reg_t CXL_SLBI_Select_An = {0x050};
+/* Interrupt Registers */
+static const cxl_p2n_reg_t CXL_PSL_DSISR_An   = {0x060};
+static const cxl_p2n_reg_t CXL_PSL_DAR_An     = {0x068};
+static const cxl_p2n_reg_t CXL_PSL_DSR_An     = {0x070};
+static const cxl_p2n_reg_t CXL_PSL_TFC_An     = {0x078};
+static const cxl_p2n_reg_t CXL_PSL_PEHandle_An = {0x080};
+static const cxl_p2n_reg_t CXL_PSL_ErrStat_An = {0x088};
+/* AFU Registers */
+static const cxl_p2n_reg_t CXL_AFU_Cntl_An    = {0x090};
+static const cxl_p2n_reg_t CXL_AFU_ERR_An     = {0x098};
+/* Work Element Descriptor */
+static const cxl_p2n_reg_t CXL_PSL_WED_An     = {0x0A0};
+/* 0x0C0:FFF Implementation Dependent Area */
+
+#define CXL_PSL_SPAP_Addr 0x0ffffffffffff000ULL
+#define CXL_PSL_SPAP_Size 0x0000000000000ff0ULL
+#define CXL_PSL_SPAP_Size_Shift 4
+#define CXL_PSL_SPAP_V    0x0000000000000001ULL
+
+/****** CXL_PSL_DLCNTL *****************************************************/
+#define CXL_PSL_DLCNTL_D (0x1ull << (63-28))
+#define CXL_PSL_DLCNTL_C (0x1ull << (63-29))
+#define CXL_PSL_DLCNTL_E (0x1ull << (63-30))
+#define CXL_PSL_DLCNTL_S (0x1ull << (63-31))
+#define CXL_PSL_DLCNTL_CE (CXL_PSL_DLCNTL_C | CXL_PSL_DLCNTL_E)
+#define CXL_PSL_DLCNTL_DCES (CXL_PSL_DLCNTL_D | CXL_PSL_DLCNTL_CE | CXL_PSL_DLCNTL_S)
+
+/****** CXL_PSL_SR_An ******************************************************/
+#define CXL_PSL_SR_An_SF  MSR_SF            /* 64bit */
+#define CXL_PSL_SR_An_TA  (1ull << (63-1))  /* Tags active,   GA1: 0 */
+#define CXL_PSL_SR_An_HV  MSR_HV            /* Hypervisor,    GA1: 0 */
+#define CXL_PSL_SR_An_PR  MSR_PR            /* Problem state, GA1: 1 */
+#define CXL_PSL_SR_An_ISL (1ull << (63-53)) /* Ignore Segment Large Page */
+#define CXL_PSL_SR_An_TC  (1ull << (63-54)) /* Page Table secondary hash */
+#define CXL_PSL_SR_An_US  (1ull << (63-56)) /* User state,    GA1: X */
+#define CXL_PSL_SR_An_SC  (1ull << (63-58)) /* Segment Table secondary hash */
+#define CXL_PSL_SR_An_R   MSR_DR            /* Relocate,      GA1: 1 */
+#define CXL_PSL_SR_An_MP  (1ull << (63-62)) /* Master Process */
+#define CXL_PSL_SR_An_LE  (1ull << (63-63)) /* Little Endian */
+
+/****** CXL_PSL_LLCMD_An ****************************************************/
+#define CXL_LLCMD_TERMINATE   0x0001000000000000ULL
+#define CXL_LLCMD_REMOVE      0x0002000000000000ULL
+#define CXL_LLCMD_SUSPEND     0x0003000000000000ULL
+#define CXL_LLCMD_RESUME      0x0004000000000000ULL
+#define CXL_LLCMD_ADD         0x0005000000000000ULL
+#define CXL_LLCMD_UPDATE      0x0006000000000000ULL
+#define CXL_LLCMD_HANDLE_MASK 0x000000000000ffffULL
+
+/****** CXL_PSL_ID_An ****************************************************/
+#define CXL_PSL_ID_An_F	(1ull << (63-31))
+#define CXL_PSL_ID_An_L	(1ull << (63-30))
+
+/****** CXL_PSL_SCNTL_An ****************************************************/
+#define CXL_PSL_SCNTL_An_CR          (0x1ull << (63-15))
+/* Programming Modes: */
+#define CXL_PSL_SCNTL_An_PM_MASK     (0xffffull << (63-31))
+#define CXL_PSL_SCNTL_An_PM_Shared   (0x0000ull << (63-31))
+#define CXL_PSL_SCNTL_An_PM_OS       (0x0001ull << (63-31))
+#define CXL_PSL_SCNTL_An_PM_Process  (0x0002ull << (63-31))
+#define CXL_PSL_SCNTL_An_PM_AFU      (0x0004ull << (63-31))
+#define CXL_PSL_SCNTL_An_PM_AFU_PBT  (0x0104ull << (63-31))
+/* Purge Status (ro) */
+#define CXL_PSL_SCNTL_An_Ps_MASK     (0x3ull << (63-39))
+#define CXL_PSL_SCNTL_An_Ps_Pending  (0x1ull << (63-39))
+#define CXL_PSL_SCNTL_An_Ps_Complete (0x3ull << (63-39))
+/* Purge */
+#define CXL_PSL_SCNTL_An_Pc          (0x1ull << (63-48))
+/* Suspend Status (ro) */
+#define CXL_PSL_SCNTL_An_Ss_MASK     (0x3ull << (63-55))
+#define CXL_PSL_SCNTL_An_Ss_Pending  (0x1ull << (63-55))
+#define CXL_PSL_SCNTL_An_Ss_Complete (0x3ull << (63-55))
+/* Suspend Control */
+#define CXL_PSL_SCNTL_An_Sc          (0x1ull << (63-63))
+
+/* AFU Slice Enable Status (ro) */
+#define CXL_AFU_Cntl_An_ES_MASK     (0x7ull << (63-2))
+#define CXL_AFU_Cntl_An_ES_Disabled (0x0ull << (63-2))
+#define CXL_AFU_Cntl_An_ES_Enabled  (0x4ull << (63-2))
+/* AFU Slice Enable */
+#define CXL_AFU_Cntl_An_E           (0x1ull << (63-3))
+/* AFU Slice Reset status (ro) */
+#define CXL_AFU_Cntl_An_RS_MASK     (0x3ull << (63-5))
+#define CXL_AFU_Cntl_An_RS_Pending  (0x1ull << (63-5))
+#define CXL_AFU_Cntl_An_RS_Complete (0x2ull << (63-5))
+/* AFU Slice Reset */
+#define CXL_AFU_Cntl_An_RA          (0x1ull << (63-7))
+
+/****** CXL_SSTP0/1_An ******************************************************/
+/* These top bits are for the segment that CONTAINS the segment table */
+#define CXL_SSTP0_An_B_SHIFT    SLB_VSID_SSIZE_SHIFT
+#define CXL_SSTP0_An_KS             (1ull << (63-2))
+#define CXL_SSTP0_An_KP             (1ull << (63-3))
+#define CXL_SSTP0_An_N              (1ull << (63-4))
+#define CXL_SSTP0_An_L              (1ull << (63-5))
+#define CXL_SSTP0_An_C              (1ull << (63-6))
+#define CXL_SSTP0_An_TA             (1ull << (63-7))
+#define CXL_SSTP0_An_LP_SHIFT                (63-9)  /* 2 Bits */
+/* And finally, the virtual address & size of the segment table: */
+#define CXL_SSTP0_An_SegTableSize_SHIFT      (63-31) /* 12 Bits */
+#define CXL_SSTP0_An_SegTableSize_MASK \
+	(((1ull << 12) - 1) << CXL_SSTP0_An_SegTableSize_SHIFT)
+#define CXL_SSTP0_An_STVA_U_MASK   ((1ull << (63-49))-1)
+#define CXL_SSTP1_An_STVA_L_MASK (~((1ull << (63-55))-1))
+#define CXL_SSTP1_An_V              (1ull << (63-63))
+
+/****** CXL_PSL_SLBIE_[An] **************************************************/
+/* write: */
+#define CXL_SLBIE_C        PPC_BIT(36)         /* Class */
+#define CXL_SLBIE_SS       PPC_BITMASK(37, 38) /* Segment Size */
+#define CXL_SLBIE_SS_SHIFT PPC_BITLSHIFT(38)
+#define CXL_SLBIE_TA       PPC_BIT(38)         /* Tags Active */
+/* read: */
+#define CXL_SLBIE_MAX      PPC_BITMASK(24, 31)
+#define CXL_SLBIE_PENDING  PPC_BITMASK(56, 63)
+
+/****** Common to all CXL_TLBIA/SLBIA_[An] **********************************/
+#define CXL_TLB_SLB_P          (1ull) /* Pending (read) */
+
+/****** Common to all CXL_TLB/SLB_IA/IE_[An] registers **********************/
+#define CXL_TLB_SLB_IQ_ALL     (0ull) /* Inv qualifier */
+#define CXL_TLB_SLB_IQ_LPID    (1ull) /* Inv qualifier */
+#define CXL_TLB_SLB_IQ_LPIDPID (3ull) /* Inv qualifier */
+
+/****** CXL_PSL_AFUSEL ******************************************************/
+#define CXL_PSL_AFUSEL_A (1ull << (63-55)) /* Adapter wide invalidates affect all AFUs */
+
+/****** CXL_PSL_DSISR_An ****************************************************/
+#define CXL_PSL_DSISR_An_DS (1ull << (63-0))  /* Segment not found */
+#define CXL_PSL_DSISR_An_DM (1ull << (63-1))  /* PTE not found (See also: M) or protection fault */
+#define CXL_PSL_DSISR_An_ST (1ull << (63-2))  /* Segment Table PTE not found */
+#define CXL_PSL_DSISR_An_UR (1ull << (63-3))  /* AURP PTE not found */
+#define CXL_PSL_DSISR_TRANS (CXL_PSL_DSISR_An_DS | CXL_PSL_DSISR_An_DM | CXL_PSL_DSISR_An_ST | CXL_PSL_DSISR_An_UR)
+#define CXL_PSL_DSISR_An_PE (1ull << (63-4))  /* PSL Error (implementation specific) */
+#define CXL_PSL_DSISR_An_AE (1ull << (63-5))  /* AFU Error */
+#define CXL_PSL_DSISR_An_OC (1ull << (63-6))  /* OS Context Warning */
+/* NOTE: Bits 32:63 are undefined if DSISR[DS] = 1 */
+#define CXL_PSL_DSISR_An_M  DSISR_NOHPTE      /* PTE not found */
+#define CXL_PSL_DSISR_An_P  DSISR_PROTFAULT   /* Storage protection violation */
+#define CXL_PSL_DSISR_An_A  (1ull << (63-37)) /* AFU lock access to write through or cache inhibited storage */
+#define CXL_PSL_DSISR_An_S  DSISR_ISSTORE     /* Access was afu_wr or afu_zero */
+#define CXL_PSL_DSISR_An_K  DSISR_KEYFAULT    /* Access not permitted by virtual page class key protection */
+
+/****** CXL_PSL_TFC_An ******************************************************/
+#define CXL_PSL_TFC_An_A  (1ull << (63-28)) /* Acknowledge non-translation fault */
+#define CXL_PSL_TFC_An_C  (1ull << (63-29)) /* Continue (abort transaction) */
+#define CXL_PSL_TFC_An_AE (1ull << (63-30)) /* Restart PSL with address error */
+#define CXL_PSL_TFC_An_R  (1ull << (63-31)) /* Restart PSL transaction */
+
+/* cxl_process_element->software_status */
+#define CXL_PE_SOFTWARE_STATE_V (1ul << (31 -  0)) /* Valid */
+#define CXL_PE_SOFTWARE_STATE_C (1ul << (31 - 29)) /* Complete */
+#define CXL_PE_SOFTWARE_STATE_S (1ul << (31 - 30)) /* Suspend */
+#define CXL_PE_SOFTWARE_STATE_T (1ul << (31 - 31)) /* Terminate */
+
+/* SPA->sw_command_status */
+#define CXL_SPA_SW_CMD_MASK         0xffff000000000000ULL
+#define CXL_SPA_SW_CMD_TERMINATE    0x0001000000000000ULL
+#define CXL_SPA_SW_CMD_REMOVE       0x0002000000000000ULL
+#define CXL_SPA_SW_CMD_SUSPEND      0x0003000000000000ULL
+#define CXL_SPA_SW_CMD_RESUME       0x0004000000000000ULL
+#define CXL_SPA_SW_CMD_ADD          0x0005000000000000ULL
+#define CXL_SPA_SW_CMD_UPDATE       0x0006000000000000ULL
+#define CXL_SPA_SW_STATE_MASK       0x0000ffff00000000ULL
+#define CXL_SPA_SW_STATE_TERMINATED 0x0000000100000000ULL
+#define CXL_SPA_SW_STATE_REMOVED    0x0000000200000000ULL
+#define CXL_SPA_SW_STATE_SUSPENDED  0x0000000300000000ULL
+#define CXL_SPA_SW_STATE_RESUMED    0x0000000400000000ULL
+#define CXL_SPA_SW_STATE_ADDED      0x0000000500000000ULL
+#define CXL_SPA_SW_STATE_UPDATED    0x0000000600000000ULL
+#define CXL_SPA_SW_PSL_ID_MASK      0x00000000ffff0000ULL
+#define CXL_SPA_SW_LINK_MASK        0x000000000000ffffULL
+
+#define CXL_MAX_SLICES 4
+#define MAX_AFU_MMIO_REGS 3
+
+#define CXL_MODE_DEDICATED   0x1
+#define CXL_MODE_DIRECTED    0x2
+#define CXL_MODE_TIME_SLICED 0x4
+#define CXL_SUPPORTED_MODES (CXL_MODE_DEDICATED | CXL_MODE_DIRECTED)
+
+enum cxl_context_status {
+	CLOSED,
+	OPENED,
+	STARTED
+};
+
+enum prefault_modes {
+	CXL_PREFAULT_NONE,
+	CXL_PREFAULT_WED,
+	CXL_PREFAULT_ALL,
+};
+
+struct cxl_sste {
+	__be64 esid_data;
+	__be64 vsid_data;
+};
+
+#define to_cxl_adapter(d) container_of(d, struct cxl, dev)
+#define to_cxl_afu(d) container_of(d, struct cxl_afu, dev)
+
+struct cxl_afu {
+	irq_hw_number_t psl_hwirq;
+	irq_hw_number_t serr_hwirq;
+	unsigned int serr_virq;
+	void __iomem *p1n_mmio;
+	void __iomem *p2n_mmio;
+	phys_addr_t psn_phys;
+	u64 pp_offset;
+	u64 pp_size;
+	void __iomem *afu_desc_mmio;
+	struct cxl *adapter;
+	struct device dev;
+	struct cdev afu_cdev_s, afu_cdev_m, afu_cdev_d;
+	struct device *chardev_s, *chardev_m, *chardev_d;
+	struct idr contexts_idr;
+	struct dentry *debugfs;
+	struct mutex contexts_lock;
+	struct mutex spa_mutex;
+	spinlock_t afu_cntl_lock;
+
+	/*
+	 * Only the first part of the SPA is used for the process element
+	 * linked list. The only other part that software needs to worry about
+	 * is sw_command_status, which we store a separate pointer to.
+	 * Everything else in the SPA is only used by hardware
+	 */
+	struct cxl_process_element *spa;
+	__be64 *sw_command_status;
+	unsigned int spa_size;
+	int spa_order;
+	int spa_max_procs;
+	unsigned int psl_virq;
+
+	int pp_irqs;
+	int irqs_max;
+	int num_procs;
+	int max_procs_virtualised;
+	int slice;
+	int modes_supported;
+	int current_mode;
+	enum prefault_modes prefault_mode;
+	bool psa;
+	bool pp_psa;
+	bool enabled;
+};
+
+/*
+ * This is a cxl context.  If the PSL is in dedicated mode, there will be one
+ * of these per AFU.  If in AFU directed there can be lots of these.
+ */
+struct cxl_context {
+	struct cxl_afu *afu;
+
+	/* Problem state MMIO */
+	phys_addr_t psn_phys;
+	u64 psn_size;
+
+	/* Used to unmap any mmaps when force detaching */
+	struct address_space *mapping;
+	struct mutex mapping_lock;
+
+	spinlock_t sste_lock; /* Protects segment table entries */
+	struct cxl_sste *sstp;
+	u64 sstp0, sstp1;
+	unsigned int sst_size, sst_lru;
+
+	wait_queue_head_t wq;
+	struct pid *pid;
+	spinlock_t lock; /* Protects pending_irq_mask, pending_fault and fault_addr */
+	/* Only used in PR mode */
+	u64 process_token;
+
+	unsigned long *irq_bitmap; /* Accessed from IRQ context */
+	struct cxl_irq_ranges irqs;
+	u64 fault_addr;
+	u64 fault_dsisr;
+	u64 afu_err;
+
+	/*
+	 * This status and it's lock pretects start and detach context
+	 * from racing.  It also prevents detach from racing with
+	 * itself
+	 */
+	enum cxl_context_status status;
+	struct mutex status_mutex;
+
+
+	/* XXX: Is it possible to need multiple work items at once? */
+	struct work_struct fault_work;
+	u64 dsisr;
+	u64 dar;
+
+	struct cxl_process_element *elem;
+
+	int pe; /* process element handle */
+	u32 irq_count;
+	bool pe_inserted;
+	bool master;
+	bool kernel;
+	bool pending_irq;
+	bool pending_fault;
+	bool pending_afu_err;
+};
+
+struct cxl {
+	void __iomem *p1_mmio;
+	void __iomem *p2_mmio;
+	irq_hw_number_t err_hwirq;
+	unsigned int err_virq;
+	spinlock_t afu_list_lock;
+	struct cxl_afu *afu[CXL_MAX_SLICES];
+	struct device dev;
+	struct dentry *trace;
+	struct dentry *psl_err_chk;
+	struct dentry *debugfs;
+	struct bin_attribute cxl_attr;
+	int adapter_num;
+	int user_irqs;
+	u64 afu_desc_off;
+	u64 afu_desc_size;
+	u64 ps_off;
+	u64 ps_size;
+	u16 psl_rev;
+	u16 base_image;
+	u8 vsec_status;
+	u8 caia_major;
+	u8 caia_minor;
+	u8 slices;
+	bool user_image_loaded;
+	bool perst_loads_image;
+	bool perst_select_user;
+};
+
+int cxl_alloc_one_irq(struct cxl *adapter);
+void cxl_release_one_irq(struct cxl *adapter, int hwirq);
+int cxl_alloc_irq_ranges(struct cxl_irq_ranges *irqs, struct cxl *adapter, unsigned int num);
+void cxl_release_irq_ranges(struct cxl_irq_ranges *irqs, struct cxl *adapter);
+int cxl_setup_irq(struct cxl *adapter, unsigned int hwirq, unsigned int virq);
+int cxl_update_image_control(struct cxl *adapter);
+
+/* common == phyp + powernv */
+struct cxl_process_element_common {
+	__be32 tid;
+	__be32 pid;
+	__be64 csrp;
+	__be64 aurp0;
+	__be64 aurp1;
+	__be64 sstp0;
+	__be64 sstp1;
+	__be64 amr;
+	u8     reserved3[4];
+	__be64 wed;
+} __packed;
+
+/* just powernv */
+struct cxl_process_element {
+	__be64 sr;
+	__be64 SPOffset;
+	__be64 sdr;
+	__be64 haurp;
+	__be32 ctxtime;
+	__be16 ivte_offsets[4];
+	__be16 ivte_ranges[4];
+	__be32 lpid;
+	struct cxl_process_element_common common;
+	__be32 software_state;
+} __packed;
+
+static inline void __iomem *_cxl_p1_addr(struct cxl *cxl, cxl_p1_reg_t reg)
+{
+	WARN_ON(!cpu_has_feature(CPU_FTR_HVMODE));
+	return cxl->p1_mmio + cxl_reg_off(reg);
+}
+
+#define cxl_p1_write(cxl, reg, val) \
+	out_be64(_cxl_p1_addr(cxl, reg), val)
+#define cxl_p1_read(cxl, reg) \
+	in_be64(_cxl_p1_addr(cxl, reg))
+
+static inline void __iomem *_cxl_p1n_addr(struct cxl_afu *afu, cxl_p1n_reg_t reg)
+{
+	WARN_ON(!cpu_has_feature(CPU_FTR_HVMODE));
+	return afu->p1n_mmio + cxl_reg_off(reg);
+}
+
+#define cxl_p1n_write(afu, reg, val) \
+	out_be64(_cxl_p1n_addr(afu, reg), val)
+#define cxl_p1n_read(afu, reg) \
+	in_be64(_cxl_p1n_addr(afu, reg))
+
+static inline void __iomem *_cxl_p2n_addr(struct cxl_afu *afu, cxl_p2n_reg_t reg)
+{
+	return afu->p2n_mmio + cxl_reg_off(reg);
+}
+
+#define cxl_p2n_write(afu, reg, val) \
+	out_be64(_cxl_p2n_addr(afu, reg), val)
+#define cxl_p2n_read(afu, reg) \
+	in_be64(_cxl_p2n_addr(afu, reg))
+
+struct cxl_calls {
+	void (*cxl_slbia)(struct mm_struct *mm);
+	struct module *owner;
+};
+int register_cxl_calls(struct cxl_calls *calls);
+void unregister_cxl_calls(struct cxl_calls *calls);
+
+int cxl_alloc_adapter_nr(struct cxl *adapter);
+void cxl_remove_adapter_nr(struct cxl *adapter);
+
+int cxl_file_init(void);
+void cxl_file_exit(void);
+int cxl_register_adapter(struct cxl *adapter);
+int cxl_register_afu(struct cxl_afu *afu);
+int cxl_chardev_d_afu_add(struct cxl_afu *afu);
+int cxl_chardev_m_afu_add(struct cxl_afu *afu);
+int cxl_chardev_s_afu_add(struct cxl_afu *afu);
+void cxl_chardev_afu_remove(struct cxl_afu *afu);
+
+void cxl_context_detach_all(struct cxl_afu *afu);
+void cxl_context_free(struct cxl_context *ctx);
+void cxl_context_detach(struct cxl_context *ctx);
+
+int cxl_sysfs_adapter_add(struct cxl *adapter);
+void cxl_sysfs_adapter_remove(struct cxl *adapter);
+int cxl_sysfs_afu_add(struct cxl_afu *afu);
+void cxl_sysfs_afu_remove(struct cxl_afu *afu);
+int cxl_sysfs_afu_m_add(struct cxl_afu *afu);
+void cxl_sysfs_afu_m_remove(struct cxl_afu *afu);
+
+int cxl_afu_activate_mode(struct cxl_afu *afu, int mode);
+int _cxl_afu_deactivate_mode(struct cxl_afu *afu, int mode);
+int cxl_afu_deactivate_mode(struct cxl_afu *afu);
+int cxl_afu_select_best_mode(struct cxl_afu *afu);
+
+unsigned int cxl_map_irq(struct cxl *adapter, irq_hw_number_t hwirq,
+		         irq_handler_t handler, void *cookie);
+void cxl_unmap_irq(unsigned int virq, void *cookie);
+int cxl_register_psl_irq(struct cxl_afu *afu);
+void cxl_release_psl_irq(struct cxl_afu *afu);
+int cxl_register_psl_err_irq(struct cxl *adapter);
+void cxl_release_psl_err_irq(struct cxl *adapter);
+int cxl_register_serr_irq(struct cxl_afu *afu);
+void cxl_release_serr_irq(struct cxl_afu *afu);
+int afu_register_irqs(struct cxl_context *ctx, u32 count);
+void afu_release_irqs(struct cxl_context *ctx);
+irqreturn_t cxl_slice_irq_err(int irq, void *data);
+
+int cxl_debugfs_init(void);
+void cxl_debugfs_exit(void);
+int cxl_debugfs_adapter_add(struct cxl *adapter);
+void cxl_debugfs_adapter_remove(struct cxl *adapter);
+int cxl_debugfs_afu_add(struct cxl_afu *afu);
+void cxl_debugfs_afu_remove(struct cxl_afu *afu);
+
+void cxl_handle_fault(struct work_struct *work);
+void cxl_prefault(struct cxl_context *ctx, u64 wed);
+
+struct cxl *get_cxl_adapter(int num);
+int cxl_alloc_sst(struct cxl_context *ctx);
+
+void init_cxl_native(void);
+
+struct cxl_context *cxl_context_alloc(void);
+int cxl_context_init(struct cxl_context *ctx, struct cxl_afu *afu, bool master,
+		     struct address_space *mapping);
+void cxl_context_free(struct cxl_context *ctx);
+int cxl_context_iomap(struct cxl_context *ctx, struct vm_area_struct *vma);
+
+/* This matches the layout of the H_COLLECT_CA_INT_INFO retbuf */
+struct cxl_irq_info {
+	u64 dsisr;
+	u64 dar;
+	u64 dsr;
+	u32 pid;
+	u32 tid;
+	u64 afu_err;
+	u64 errstat;
+	u64 padding[3]; /* to match the expected retbuf size for plpar_hcall9 */
+};
+
+int cxl_attach_process(struct cxl_context *ctx, bool kernel, u64 wed,
+			    u64 amr);
+int cxl_detach_process(struct cxl_context *ctx);
+
+int cxl_get_irq(struct cxl_context *ctx, struct cxl_irq_info *info);
+int cxl_ack_irq(struct cxl_context *ctx, u64 tfc, u64 psl_reset_mask);
+
+int cxl_check_error(struct cxl_afu *afu);
+int cxl_afu_slbia(struct cxl_afu *afu);
+int cxl_tlb_slb_invalidate(struct cxl *adapter);
+int cxl_afu_disable(struct cxl_afu *afu);
+int cxl_afu_reset(struct cxl_afu *afu);
+int cxl_psl_purge(struct cxl_afu *afu);
+
+void cxl_stop_trace(struct cxl *cxl);
+
+extern struct pci_driver cxl_pci_driver;
+
+#endif

drivers/misc/cxl/debugfs.c

@@ -0,0 +1,132 @@
+/*
+ * Copyright 2014 IBM Corp.
+ *
+ * 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.
+ */
+
+#include <linux/debugfs.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+
+#include "cxl.h"
+
+static struct dentry *cxl_debugfs;
+
+void cxl_stop_trace(struct cxl *adapter)
+{
+	int slice;
+
+	/* Stop the trace */
+	cxl_p1_write(adapter, CXL_PSL_TRACE, 0x8000000000000017LL);
+
+	/* Stop the slice traces */
+	spin_lock(&adapter->afu_list_lock);
+	for (slice = 0; slice < adapter->slices; slice++) {
+		if (adapter->afu[slice])
+			cxl_p1n_write(adapter->afu[slice], CXL_PSL_SLICE_TRACE, 0x8000000000000000LL);
+	}
+	spin_unlock(&adapter->afu_list_lock);
+}
+
+/* Helpers to export CXL mmaped IO registers via debugfs */
+static int debugfs_io_u64_get(void *data, u64 *val)
+{
+	*val = in_be64((u64 __iomem *)data);
+	return 0;
+}
+
+static int debugfs_io_u64_set(void *data, u64 val)
+{
+	out_be64((u64 __iomem *)data, val);
+	return 0;
+}
+DEFINE_SIMPLE_ATTRIBUTE(fops_io_x64, debugfs_io_u64_get, debugfs_io_u64_set, "0x%016llx\n");
+
+static struct dentry *debugfs_create_io_x64(const char *name, umode_t mode,
+					    struct dentry *parent, u64 __iomem *value)
+{
+	return debugfs_create_file(name, mode, parent, (void *)value, &fops_io_x64);
+}
+
+int cxl_debugfs_adapter_add(struct cxl *adapter)
+{
+	struct dentry *dir;
+	char buf[32];
+
+	if (!cxl_debugfs)
+		return -ENODEV;
+
+	snprintf(buf, 32, "card%i", adapter->adapter_num);
+	dir = debugfs_create_dir(buf, cxl_debugfs);
+	if (IS_ERR(dir))
+		return PTR_ERR(dir);
+	adapter->debugfs = dir;
+
+	debugfs_create_io_x64("fir1",     S_IRUSR, dir, _cxl_p1_addr(adapter, CXL_PSL_FIR1));
+	debugfs_create_io_x64("fir2",     S_IRUSR, dir, _cxl_p1_addr(adapter, CXL_PSL_FIR2));
+	debugfs_create_io_x64("fir_cntl", S_IRUSR, dir, _cxl_p1_addr(adapter, CXL_PSL_FIR_CNTL));
+	debugfs_create_io_x64("err_ivte", S_IRUSR, dir, _cxl_p1_addr(adapter, CXL_PSL_ErrIVTE));
+
+	debugfs_create_io_x64("trace", S_IRUSR | S_IWUSR, dir, _cxl_p1_addr(adapter, CXL_PSL_TRACE));
+
+	return 0;
+}
+
+void cxl_debugfs_adapter_remove(struct cxl *adapter)
+{
+	debugfs_remove_recursive(adapter->debugfs);
+}
+
+int cxl_debugfs_afu_add(struct cxl_afu *afu)
+{
+	struct dentry *dir;
+	char buf[32];
+
+	if (!afu->adapter->debugfs)
+		return -ENODEV;
+
+	snprintf(buf, 32, "psl%i.%i", afu->adapter->adapter_num, afu->slice);
+	dir = debugfs_create_dir(buf, afu->adapter->debugfs);
+	if (IS_ERR(dir))
+		return PTR_ERR(dir);
+	afu->debugfs = dir;
+
+	debugfs_create_io_x64("fir",        S_IRUSR, dir, _cxl_p1n_addr(afu, CXL_PSL_FIR_SLICE_An));
+	debugfs_create_io_x64("serr",       S_IRUSR, dir, _cxl_p1n_addr(afu, CXL_PSL_SERR_An));
+	debugfs_create_io_x64("afu_debug",  S_IRUSR, dir, _cxl_p1n_addr(afu, CXL_AFU_DEBUG_An));
+	debugfs_create_io_x64("sr",         S_IRUSR, dir, _cxl_p1n_addr(afu, CXL_PSL_SR_An));
+
+	debugfs_create_io_x64("dsisr",      S_IRUSR, dir, _cxl_p2n_addr(afu, CXL_PSL_DSISR_An));
+	debugfs_create_io_x64("dar",        S_IRUSR, dir, _cxl_p2n_addr(afu, CXL_PSL_DAR_An));
+	debugfs_create_io_x64("sstp0",      S_IRUSR, dir, _cxl_p2n_addr(afu, CXL_SSTP0_An));
+	debugfs_create_io_x64("sstp1",      S_IRUSR, dir, _cxl_p2n_addr(afu, CXL_SSTP1_An));
+	debugfs_create_io_x64("err_status", S_IRUSR, dir, _cxl_p2n_addr(afu, CXL_PSL_ErrStat_An));
+
+	debugfs_create_io_x64("trace", S_IRUSR | S_IWUSR, dir, _cxl_p1n_addr(afu, CXL_PSL_SLICE_TRACE));
+
+	return 0;
+}
+
+void cxl_debugfs_afu_remove(struct cxl_afu *afu)
+{
+	debugfs_remove_recursive(afu->debugfs);
+}
+
+int __init cxl_debugfs_init(void)
+{
+	struct dentry *ent;
+	ent = debugfs_create_dir("cxl", NULL);
+	if (IS_ERR(ent))
+		return PTR_ERR(ent);
+	cxl_debugfs = ent;
+
+	return 0;
+}
+
+void cxl_debugfs_exit(void)
+{
+	debugfs_remove_recursive(cxl_debugfs);
+}

drivers/misc/cxl/fault.c

@@ -0,0 +1,295 @@
+/*
+ * Copyright 2014 IBM Corp.
+ *
+ * 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.
+ */
+
+#include <linux/workqueue.h>
+#include <linux/sched.h>
+#include <linux/pid.h>
+#include <linux/mm.h>
+#include <linux/moduleparam.h>
+
+#undef MODULE_PARAM_PREFIX
+#define MODULE_PARAM_PREFIX "cxl" "."
+#include <asm/current.h>
+#include <asm/copro.h>
+#include <asm/mmu.h>
+
+#include "cxl.h"
+
+static bool sste_matches(struct cxl_sste *sste, struct copro_slb *slb)
+{
+	return ((sste->vsid_data == cpu_to_be64(slb->vsid)) &&
+		(sste->esid_data == cpu_to_be64(slb->esid)));
+}
+
+/*
+ * This finds a free SSTE for the given SLB, or returns NULL if it's already in
+ * the segment table.
+ */
+static struct cxl_sste* find_free_sste(struct cxl_context *ctx,
+				       struct copro_slb *slb)
+{
+	struct cxl_sste *primary, *sste, *ret = NULL;
+	unsigned int mask = (ctx->sst_size >> 7) - 1; /* SSTP0[SegTableSize] */
+	unsigned int entry;
+	unsigned int hash;
+
+	if (slb->vsid & SLB_VSID_B_1T)
+		hash = (slb->esid >> SID_SHIFT_1T) & mask;
+	else /* 256M */
+		hash = (slb->esid >> SID_SHIFT) & mask;
+
+	primary = ctx->sstp + (hash << 3);
+
+	for (entry = 0, sste = primary; entry < 8; entry++, sste++) {
+		if (!ret && !(be64_to_cpu(sste->esid_data) & SLB_ESID_V))
+			ret = sste;
+		if (sste_matches(sste, slb))
+			return NULL;
+	}
+	if (ret)
+		return ret;
+
+	/* Nothing free, select an entry to cast out */
+	ret = primary + ctx->sst_lru;
+	ctx->sst_lru = (ctx->sst_lru + 1) & 0x7;
+
+	return ret;
+}
+
+static void cxl_load_segment(struct cxl_context *ctx, struct copro_slb *slb)
+{
+	/* mask is the group index, we search primary and secondary here. */
+	struct cxl_sste *sste;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ctx->sste_lock, flags);
+	sste = find_free_sste(ctx, slb);
+	if (!sste)
+		goto out_unlock;
+
+	pr_devel("CXL Populating SST[%li]: %#llx %#llx\n",
+			sste - ctx->sstp, slb->vsid, slb->esid);
+
+	sste->vsid_data = cpu_to_be64(slb->vsid);
+	sste->esid_data = cpu_to_be64(slb->esid);
+out_unlock:
+	spin_unlock_irqrestore(&ctx->sste_lock, flags);
+}
+
+static int cxl_fault_segment(struct cxl_context *ctx, struct mm_struct *mm,
+			     u64 ea)
+{
+	struct copro_slb slb = {0,0};
+	int rc;
+
+	if (!(rc = copro_calculate_slb(mm, ea, &slb))) {
+		cxl_load_segment(ctx, &slb);
+	}
+
+	return rc;
+}
+
+static void cxl_ack_ae(struct cxl_context *ctx)
+{
+	unsigned long flags;
+
+	cxl_ack_irq(ctx, CXL_PSL_TFC_An_AE, 0);
+
+	spin_lock_irqsave(&ctx->lock, flags);
+	ctx->pending_fault = true;
+	ctx->fault_addr = ctx->dar;
+	ctx->fault_dsisr = ctx->dsisr;
+	spin_unlock_irqrestore(&ctx->lock, flags);
+
+	wake_up_all(&ctx->wq);
+}
+
+static int cxl_handle_segment_miss(struct cxl_context *ctx,
+				   struct mm_struct *mm, u64 ea)
+{
+	int rc;
+
+	pr_devel("CXL interrupt: Segment fault pe: %i ea: %#llx\n", ctx->pe, ea);
+
+	if ((rc = cxl_fault_segment(ctx, mm, ea)))
+		cxl_ack_ae(ctx);
+	else {
+
+		mb(); /* Order seg table write to TFC MMIO write */
+		cxl_ack_irq(ctx, CXL_PSL_TFC_An_R, 0);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static void cxl_handle_page_fault(struct cxl_context *ctx,
+				  struct mm_struct *mm, u64 dsisr, u64 dar)
+{
+	unsigned flt = 0;
+	int result;
+	unsigned long access, flags;
+
+	if ((result = copro_handle_mm_fault(mm, dar, dsisr, &flt))) {
+		pr_devel("copro_handle_mm_fault failed: %#x\n", result);
+		return cxl_ack_ae(ctx);
+	}
+
+	/*
+	 * update_mmu_cache() will not have loaded the hash since current->trap
+	 * is not a 0x400 or 0x300, so just call hash_page_mm() here.
+	 */
+	access = _PAGE_PRESENT;
+	if (dsisr & CXL_PSL_DSISR_An_S)
+		access |= _PAGE_RW;
+	if ((!ctx->kernel) || ~(dar & (1ULL << 63)))
+		access |= _PAGE_USER;
+	local_irq_save(flags);
+	hash_page_mm(mm, dar, access, 0x300);
+	local_irq_restore(flags);
+
+	pr_devel("Page fault successfully handled for pe: %i!\n", ctx->pe);
+	cxl_ack_irq(ctx, CXL_PSL_TFC_An_R, 0);
+}
+
+void cxl_handle_fault(struct work_struct *fault_work)
+{
+	struct cxl_context *ctx =
+		container_of(fault_work, struct cxl_context, fault_work);
+	u64 dsisr = ctx->dsisr;
+	u64 dar = ctx->dar;
+	struct task_struct *task;
+	struct mm_struct *mm;
+
+	if (cxl_p2n_read(ctx->afu, CXL_PSL_DSISR_An) != dsisr ||
+	    cxl_p2n_read(ctx->afu, CXL_PSL_DAR_An) != dar ||
+	    cxl_p2n_read(ctx->afu, CXL_PSL_PEHandle_An) != ctx->pe) {
+		/* Most likely explanation is harmless - a dedicated process
+		 * has detached and these were cleared by the PSL purge, but
+		 * warn about it just in case */
+		dev_notice(&ctx->afu->dev, "cxl_handle_fault: Translation fault regs changed\n");
+		return;
+	}
+
+	pr_devel("CXL BOTTOM HALF handling fault for afu pe: %i. "
+		"DSISR: %#llx DAR: %#llx\n", ctx->pe, dsisr, dar);
+
+	if (!(task = get_pid_task(ctx->pid, PIDTYPE_PID))) {
+		pr_devel("cxl_handle_fault unable to get task %i\n",
+			 pid_nr(ctx->pid));
+		cxl_ack_ae(ctx);
+		return;
+	}
+	if (!(mm = get_task_mm(task))) {
+		pr_devel("cxl_handle_fault unable to get mm %i\n",
+			 pid_nr(ctx->pid));
+		cxl_ack_ae(ctx);
+		goto out;
+	}
+
+	if (dsisr & CXL_PSL_DSISR_An_DS)
+		cxl_handle_segment_miss(ctx, mm, dar);
+	else if (dsisr & CXL_PSL_DSISR_An_DM)
+		cxl_handle_page_fault(ctx, mm, dsisr, dar);
+	else
+		WARN(1, "cxl_handle_fault has nothing to handle\n");
+
+	mmput(mm);
+out:
+	put_task_struct(task);
+}
+
+static void cxl_prefault_one(struct cxl_context *ctx, u64 ea)
+{
+	int rc;
+	struct task_struct *task;
+	struct mm_struct *mm;
+
+	if (!(task = get_pid_task(ctx->pid, PIDTYPE_PID))) {
+		pr_devel("cxl_prefault_one unable to get task %i\n",
+			 pid_nr(ctx->pid));
+		return;
+	}
+	if (!(mm = get_task_mm(task))) {
+		pr_devel("cxl_prefault_one unable to get mm %i\n",
+			 pid_nr(ctx->pid));
+		put_task_struct(task);
+		return;
+	}
+
+	rc = cxl_fault_segment(ctx, mm, ea);
+
+	mmput(mm);
+	put_task_struct(task);
+}
+
+static u64 next_segment(u64 ea, u64 vsid)
+{
+	if (vsid & SLB_VSID_B_1T)
+		ea |= (1ULL << 40) - 1;
+	else
+		ea |= (1ULL << 28) - 1;
+
+	return ea + 1;
+}
+
+static void cxl_prefault_vma(struct cxl_context *ctx)
+{
+	u64 ea, last_esid = 0;
+	struct copro_slb slb;
+	struct vm_area_struct *vma;
+	int rc;
+	struct task_struct *task;
+	struct mm_struct *mm;
+
+	if (!(task = get_pid_task(ctx->pid, PIDTYPE_PID))) {
+		pr_devel("cxl_prefault_vma unable to get task %i\n",
+			 pid_nr(ctx->pid));
+		return;
+	}
+	if (!(mm = get_task_mm(task))) {
+		pr_devel("cxl_prefault_vm unable to get mm %i\n",
+			 pid_nr(ctx->pid));
+		goto out1;
+	}
+
+	down_read(&mm->mmap_sem);
+	for (vma = mm->mmap; vma; vma = vma->vm_next) {
+		for (ea = vma->vm_start; ea < vma->vm_end;
+				ea = next_segment(ea, slb.vsid)) {
+			rc = copro_calculate_slb(mm, ea, &slb);
+			if (rc)
+				continue;
+
+			if (last_esid == slb.esid)
+				continue;
+
+			cxl_load_segment(ctx, &slb);
+			last_esid = slb.esid;
+		}
+	}
+	up_read(&mm->mmap_sem);
+
+	mmput(mm);
+out1:
+	put_task_struct(task);
+}
+
+void cxl_prefault(struct cxl_context *ctx, u64 wed)
+{
+	switch (ctx->afu->prefault_mode) {
+	case CXL_PREFAULT_WED:
+		cxl_prefault_one(ctx, wed);
+		break;
+	case CXL_PREFAULT_ALL:
+		cxl_prefault_vma(ctx);
+		break;
+	default:
+		break;
+	}
+}

drivers/misc/cxl/file.c

@@ -0,0 +1,522 @@
+/*
+ * Copyright 2014 IBM Corp.
+ *
+ * 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.
+ */
+
+#include <linux/spinlock.h>
+#include <linux/module.h>
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/bitmap.h>
+#include <linux/sched.h>
+#include <linux/poll.h>
+#include <linux/pid.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <asm/cputable.h>
+#include <asm/current.h>
+#include <asm/copro.h>
+
+#include "cxl.h"
+
+#define CXL_NUM_MINORS 256 /* Total to reserve */
+#define CXL_DEV_MINORS 13   /* 1 control + 4 AFUs * 3 (dedicated/master/shared) */
+
+#define CXL_CARD_MINOR(adapter) (adapter->adapter_num * CXL_DEV_MINORS)
+#define CXL_AFU_MINOR_D(afu) (CXL_CARD_MINOR(afu->adapter) + 1 + (3 * afu->slice))
+#define CXL_AFU_MINOR_M(afu) (CXL_AFU_MINOR_D(afu) + 1)
+#define CXL_AFU_MINOR_S(afu) (CXL_AFU_MINOR_D(afu) + 2)
+#define CXL_AFU_MKDEV_D(afu) MKDEV(MAJOR(cxl_dev), CXL_AFU_MINOR_D(afu))
+#define CXL_AFU_MKDEV_M(afu) MKDEV(MAJOR(cxl_dev), CXL_AFU_MINOR_M(afu))
+#define CXL_AFU_MKDEV_S(afu) MKDEV(MAJOR(cxl_dev), CXL_AFU_MINOR_S(afu))
+
+#define CXL_DEVT_ADAPTER(dev) (MINOR(dev) / CXL_DEV_MINORS)
+#define CXL_DEVT_AFU(dev) ((MINOR(dev) % CXL_DEV_MINORS - 1) / 3)
+
+#define CXL_DEVT_IS_CARD(dev) (MINOR(dev) % CXL_DEV_MINORS == 0)
+
+static dev_t cxl_dev;
+
+static struct class *cxl_class;
+
+static int __afu_open(struct inode *inode, struct file *file, bool master)
+{
+	struct cxl *adapter;
+	struct cxl_afu *afu;
+	struct cxl_context *ctx;
+	int adapter_num = CXL_DEVT_ADAPTER(inode->i_rdev);
+	int slice = CXL_DEVT_AFU(inode->i_rdev);
+	int rc = -ENODEV;
+
+	pr_devel("afu_open afu%i.%i\n", slice, adapter_num);
+
+	if (!(adapter = get_cxl_adapter(adapter_num)))
+		return -ENODEV;
+
+	if (slice > adapter->slices)
+		goto err_put_adapter;
+
+	spin_lock(&adapter->afu_list_lock);
+	if (!(afu = adapter->afu[slice])) {
+		spin_unlock(&adapter->afu_list_lock);
+		goto err_put_adapter;
+	}
+	get_device(&afu->dev);
+	spin_unlock(&adapter->afu_list_lock);
+
+	if (!afu->current_mode)
+		goto err_put_afu;
+
+	if (!(ctx = cxl_context_alloc())) {
+		rc = -ENOMEM;
+		goto err_put_afu;
+	}
+
+	if ((rc = cxl_context_init(ctx, afu, master, inode->i_mapping)))
+		goto err_put_afu;
+
+	pr_devel("afu_open pe: %i\n", ctx->pe);
+	file->private_data = ctx;
+	cxl_ctx_get();
+
+	/* Our ref on the AFU will now hold the adapter */
+	put_device(&adapter->dev);
+
+	return 0;
+
+err_put_afu:
+	put_device(&afu->dev);
+err_put_adapter:
+	put_device(&adapter->dev);
+	return rc;
+}
+static int afu_open(struct inode *inode, struct file *file)
+{
+	return __afu_open(inode, file, false);
+}
+
+static int afu_master_open(struct inode *inode, struct file *file)
+{
+	return __afu_open(inode, file, true);
+}
+
+static int afu_release(struct inode *inode, struct file *file)
+{
+	struct cxl_context *ctx = file->private_data;
+
+	pr_devel("%s: closing cxl file descriptor. pe: %i\n",
+		 __func__, ctx->pe);
+	cxl_context_detach(ctx);
+
+	mutex_lock(&ctx->mapping_lock);
+	ctx->mapping = NULL;
+	mutex_unlock(&ctx->mapping_lock);
+
+	put_device(&ctx->afu->dev);
+
+	/*
+	 * At this this point all bottom halfs have finished and we should be
+	 * getting no more IRQs from the hardware for this context.  Once it's
+	 * removed from the IDR (and RCU synchronised) it's safe to free the
+	 * sstp and context.
+	 */
+	cxl_context_free(ctx);
+
+	cxl_ctx_put();
+	return 0;
+}
+
+static long afu_ioctl_start_work(struct cxl_context *ctx,
+				 struct cxl_ioctl_start_work __user *uwork)
+{
+	struct cxl_ioctl_start_work work;
+	u64 amr = 0;
+	int rc;
+
+	pr_devel("%s: pe: %i\n", __func__, ctx->pe);
+
+	mutex_lock(&ctx->status_mutex);
+	if (ctx->status != OPENED) {
+		rc = -EIO;
+		goto out;
+	}
+
+	if (copy_from_user(&work, uwork,
+			   sizeof(struct cxl_ioctl_start_work))) {
+		rc = -EFAULT;
+		goto out;
+	}
+
+	/*
+	 * if any of the reserved fields are set or any of the unused
+	 * flags are set it's invalid
+	 */
+	if (work.reserved1 || work.reserved2 || work.reserved3 ||
+	    work.reserved4 || work.reserved5 || work.reserved6 ||
+	    (work.flags & ~CXL_START_WORK_ALL)) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	if (!(work.flags & CXL_START_WORK_NUM_IRQS))
+		work.num_interrupts = ctx->afu->pp_irqs;
+	else if ((work.num_interrupts < ctx->afu->pp_irqs) ||
+		 (work.num_interrupts > ctx->afu->irqs_max)) {
+		rc =  -EINVAL;
+		goto out;
+	}
+	if ((rc = afu_register_irqs(ctx, work.num_interrupts)))
+		goto out;
+
+	if (work.flags & CXL_START_WORK_AMR)
+		amr = work.amr & mfspr(SPRN_UAMOR);
+
+	/*
+	 * We grab the PID here and not in the file open to allow for the case
+	 * where a process (master, some daemon, etc) has opened the chardev on
+	 * behalf of another process, so the AFU's mm gets bound to the process
+	 * that performs this ioctl and not the process that opened the file.
+	 */
+	ctx->pid = get_pid(get_task_pid(current, PIDTYPE_PID));
+
+	if ((rc = cxl_attach_process(ctx, false, work.work_element_descriptor,
+				     amr)))
+		goto out;
+
+	ctx->status = STARTED;
+	rc = 0;
+out:
+	mutex_unlock(&ctx->status_mutex);
+	return rc;
+}
+static long afu_ioctl_process_element(struct cxl_context *ctx,
+				      int __user *upe)
+{
+	pr_devel("%s: pe: %i\n", __func__, ctx->pe);
+
+	if (copy_to_user(upe, &ctx->pe, sizeof(__u32)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static long afu_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	struct cxl_context *ctx = file->private_data;
+
+	if (ctx->status == CLOSED)
+		return -EIO;
+
+	pr_devel("afu_ioctl\n");
+	switch (cmd) {
+	case CXL_IOCTL_START_WORK:
+		return afu_ioctl_start_work(ctx, (struct cxl_ioctl_start_work __user *)arg);
+	case CXL_IOCTL_GET_PROCESS_ELEMENT:
+		return afu_ioctl_process_element(ctx, (__u32 __user *)arg);
+	}
+	return -EINVAL;
+}
+
+static long afu_compat_ioctl(struct file *file, unsigned int cmd,
+			     unsigned long arg)
+{
+	return afu_ioctl(file, cmd, arg);
+}
+
+static int afu_mmap(struct file *file, struct vm_area_struct *vm)
+{
+	struct cxl_context *ctx = file->private_data;
+
+	/* AFU must be started before we can MMIO */
+	if (ctx->status != STARTED)
+		return -EIO;
+
+	return cxl_context_iomap(ctx, vm);
+}
+
+static unsigned int afu_poll(struct file *file, struct poll_table_struct *poll)
+{
+	struct cxl_context *ctx = file->private_data;
+	int mask = 0;
+	unsigned long flags;
+
+
+	poll_wait(file, &ctx->wq, poll);
+
+	pr_devel("afu_poll wait done pe: %i\n", ctx->pe);
+
+	spin_lock_irqsave(&ctx->lock, flags);
+	if (ctx->pending_irq || ctx->pending_fault ||
+	    ctx->pending_afu_err)
+		mask |= POLLIN | POLLRDNORM;
+	else if (ctx->status == CLOSED)
+		/* Only error on closed when there are no futher events pending
+		 */
+		mask |= POLLERR;
+	spin_unlock_irqrestore(&ctx->lock, flags);
+
+	pr_devel("afu_poll pe: %i returning %#x\n", ctx->pe, mask);
+
+	return mask;
+}
+
+static inline int ctx_event_pending(struct cxl_context *ctx)
+{
+	return (ctx->pending_irq || ctx->pending_fault ||
+	    ctx->pending_afu_err || (ctx->status == CLOSED));
+}
+
+static ssize_t afu_read(struct file *file, char __user *buf, size_t count,
+			loff_t *off)
+{
+	struct cxl_context *ctx = file->private_data;
+	struct cxl_event event;
+	unsigned long flags;
+	int rc;
+	DEFINE_WAIT(wait);
+
+	if (count < CXL_READ_MIN_SIZE)
+		return -EINVAL;
+
+	spin_lock_irqsave(&ctx->lock, flags);
+
+	for (;;) {
+		prepare_to_wait(&ctx->wq, &wait, TASK_INTERRUPTIBLE);
+		if (ctx_event_pending(ctx))
+			break;
+
+		if (file->f_flags & O_NONBLOCK) {
+			rc = -EAGAIN;
+			goto out;
+		}
+
+		if (signal_pending(current)) {
+			rc = -ERESTARTSYS;
+			goto out;
+		}
+
+		spin_unlock_irqrestore(&ctx->lock, flags);
+		pr_devel("afu_read going to sleep...\n");
+		schedule();
+		pr_devel("afu_read woken up\n");
+		spin_lock_irqsave(&ctx->lock, flags);
+	}
+
+	finish_wait(&ctx->wq, &wait);
+
+	memset(&event, 0, sizeof(event));
+	event.header.process_element = ctx->pe;
+	event.header.size = sizeof(struct cxl_event_header);
+	if (ctx->pending_irq) {
+		pr_devel("afu_read delivering AFU interrupt\n");
+		event.header.size += sizeof(struct cxl_event_afu_interrupt);
+		event.header.type = CXL_EVENT_AFU_INTERRUPT;
+		event.irq.irq = find_first_bit(ctx->irq_bitmap, ctx->irq_count) + 1;
+		clear_bit(event.irq.irq - 1, ctx->irq_bitmap);
+		if (bitmap_empty(ctx->irq_bitmap, ctx->irq_count))
+			ctx->pending_irq = false;
+	} else if (ctx->pending_fault) {
+		pr_devel("afu_read delivering data storage fault\n");
+		event.header.size += sizeof(struct cxl_event_data_storage);
+		event.header.type = CXL_EVENT_DATA_STORAGE;
+		event.fault.addr = ctx->fault_addr;
+		event.fault.dsisr = ctx->fault_dsisr;
+		ctx->pending_fault = false;
+	} else if (ctx->pending_afu_err) {
+		pr_devel("afu_read delivering afu error\n");
+		event.header.size += sizeof(struct cxl_event_afu_error);
+		event.header.type = CXL_EVENT_AFU_ERROR;
+		event.afu_error.error = ctx->afu_err;
+		ctx->pending_afu_err = false;
+	} else if (ctx->status == CLOSED) {
+		pr_devel("afu_read fatal error\n");
+		spin_unlock_irqrestore(&ctx->lock, flags);
+		return -EIO;
+	} else
+		WARN(1, "afu_read must be buggy\n");
+
+	spin_unlock_irqrestore(&ctx->lock, flags);
+
+	if (copy_to_user(buf, &event, event.header.size))
+		return -EFAULT;
+	return event.header.size;
+
+out:
+	finish_wait(&ctx->wq, &wait);
+	spin_unlock_irqrestore(&ctx->lock, flags);
+	return rc;
+}
+
+static const struct file_operations afu_fops = {
+	.owner		= THIS_MODULE,
+	.open           = afu_open,
+	.poll		= afu_poll,
+	.read		= afu_read,
+	.release        = afu_release,
+	.unlocked_ioctl = afu_ioctl,
+	.compat_ioctl   = afu_compat_ioctl,
+	.mmap           = afu_mmap,
+};
+
+static const struct file_operations afu_master_fops = {
+	.owner		= THIS_MODULE,
+	.open           = afu_master_open,
+	.poll		= afu_poll,
+	.read		= afu_read,
+	.release        = afu_release,
+	.unlocked_ioctl = afu_ioctl,
+	.compat_ioctl   = afu_compat_ioctl,
+	.mmap           = afu_mmap,
+};
+
+
+static char *cxl_devnode(struct device *dev, umode_t *mode)
+{
+	if (CXL_DEVT_IS_CARD(dev->devt)) {
+		/*
+		 * These minor numbers will eventually be used to program the
+		 * PSL and AFUs once we have dynamic reprogramming support
+		 */
+		return NULL;
+	}
+	return kasprintf(GFP_KERNEL, "cxl/%s", dev_name(dev));
+}
+
+extern struct class *cxl_class;
+
+static int cxl_add_chardev(struct cxl_afu *afu, dev_t devt, struct cdev *cdev,
+			   struct device **chardev, char *postfix, char *desc,
+			   const struct file_operations *fops)
+{
+	struct device *dev;
+	int rc;
+
+	cdev_init(cdev, fops);
+	if ((rc = cdev_add(cdev, devt, 1))) {
+		dev_err(&afu->dev, "Unable to add %s chardev: %i\n", desc, rc);
+		return rc;
+	}
+
+	dev = device_create(cxl_class, &afu->dev, devt, afu,
+			"afu%i.%i%s", afu->adapter->adapter_num, afu->slice, postfix);
+	if (IS_ERR(dev)) {
+		dev_err(&afu->dev, "Unable to create %s chardev in sysfs: %i\n", desc, rc);
+		rc = PTR_ERR(dev);
+		goto err;
+	}
+
+	*chardev = dev;
+
+	return 0;
+err:
+	cdev_del(cdev);
+	return rc;
+}
+
+int cxl_chardev_d_afu_add(struct cxl_afu *afu)
+{
+	return cxl_add_chardev(afu, CXL_AFU_MKDEV_D(afu), &afu->afu_cdev_d,
+			       &afu->chardev_d, "d", "dedicated",
+			       &afu_master_fops); /* Uses master fops */
+}
+
+int cxl_chardev_m_afu_add(struct cxl_afu *afu)
+{
+	return cxl_add_chardev(afu, CXL_AFU_MKDEV_M(afu), &afu->afu_cdev_m,
+			       &afu->chardev_m, "m", "master",
+			       &afu_master_fops);
+}
+
+int cxl_chardev_s_afu_add(struct cxl_afu *afu)
+{
+	return cxl_add_chardev(afu, CXL_AFU_MKDEV_S(afu), &afu->afu_cdev_s,
+			       &afu->chardev_s, "s", "shared",
+			       &afu_fops);
+}
+
+void cxl_chardev_afu_remove(struct cxl_afu *afu)
+{
+	if (afu->chardev_d) {
+		cdev_del(&afu->afu_cdev_d);
+		device_unregister(afu->chardev_d);
+		afu->chardev_d = NULL;
+	}
+	if (afu->chardev_m) {
+		cdev_del(&afu->afu_cdev_m);
+		device_unregister(afu->chardev_m);
+		afu->chardev_m = NULL;
+	}
+	if (afu->chardev_s) {
+		cdev_del(&afu->afu_cdev_s);
+		device_unregister(afu->chardev_s);
+		afu->chardev_s = NULL;
+	}
+}
+
+int cxl_register_afu(struct cxl_afu *afu)
+{
+	afu->dev.class = cxl_class;
+
+	return device_register(&afu->dev);
+}
+
+int cxl_register_adapter(struct cxl *adapter)
+{
+	adapter->dev.class = cxl_class;
+
+	/*
+	 * Future: When we support dynamically reprogramming the PSL & AFU we
+	 * will expose the interface to do that via a chardev:
+	 * adapter->dev.devt = CXL_CARD_MKDEV(adapter);
+	 */
+
+	return device_register(&adapter->dev);
+}
+
+int __init cxl_file_init(void)
+{
+	int rc;
+
+	/*
+	 * If these change we really need to update API.  Either change some
+	 * flags or update API version number CXL_API_VERSION.
+	 */
+	BUILD_BUG_ON(CXL_API_VERSION != 1);
+	BUILD_BUG_ON(sizeof(struct cxl_ioctl_start_work) != 64);
+	BUILD_BUG_ON(sizeof(struct cxl_event_header) != 8);
+	BUILD_BUG_ON(sizeof(struct cxl_event_afu_interrupt) != 8);
+	BUILD_BUG_ON(sizeof(struct cxl_event_data_storage) != 32);
+	BUILD_BUG_ON(sizeof(struct cxl_event_afu_error) != 16);
+
+	if ((rc = alloc_chrdev_region(&cxl_dev, 0, CXL_NUM_MINORS, "cxl"))) {
+		pr_err("Unable to allocate CXL major number: %i\n", rc);
+		return rc;
+	}
+
+	pr_devel("CXL device allocated, MAJOR %i\n", MAJOR(cxl_dev));
+
+	cxl_class = class_create(THIS_MODULE, "cxl");
+	if (IS_ERR(cxl_class)) {
+		pr_err("Unable to create CXL class\n");
+		rc = PTR_ERR(cxl_class);
+		goto err;
+	}
+	cxl_class->devnode = cxl_devnode;
+
+	return 0;
+
+err:
+	unregister_chrdev_region(cxl_dev, CXL_NUM_MINORS);
+	return rc;
+}
+
+void cxl_file_exit(void)
+{
+	unregister_chrdev_region(cxl_dev, CXL_NUM_MINORS);
+	class_destroy(cxl_class);
+}

drivers/misc/cxl/irq.c

@@ -0,0 +1,403 @@
+/*
+ * Copyright 2014 IBM Corp.
+ *
+ * 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.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/workqueue.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/slab.h>
+#include <linux/pid.h>
+#include <asm/cputable.h>
+#include <misc/cxl.h>
+
+#include "cxl.h"
+
+/* XXX: This is implementation specific */
+static irqreturn_t handle_psl_slice_error(struct cxl_context *ctx, u64 dsisr, u64 errstat)
+{
+	u64 fir1, fir2, fir_slice, serr, afu_debug;
+
+	fir1 = cxl_p1_read(ctx->afu->adapter, CXL_PSL_FIR1);
+	fir2 = cxl_p1_read(ctx->afu->adapter, CXL_PSL_FIR2);
+	fir_slice = cxl_p1n_read(ctx->afu, CXL_PSL_FIR_SLICE_An);
+	serr = cxl_p1n_read(ctx->afu, CXL_PSL_SERR_An);
+	afu_debug = cxl_p1n_read(ctx->afu, CXL_AFU_DEBUG_An);
+
+	dev_crit(&ctx->afu->dev, "PSL ERROR STATUS: 0x%.16llx\n", errstat);
+	dev_crit(&ctx->afu->dev, "PSL_FIR1: 0x%.16llx\n", fir1);
+	dev_crit(&ctx->afu->dev, "PSL_FIR2: 0x%.16llx\n", fir2);
+	dev_crit(&ctx->afu->dev, "PSL_SERR_An: 0x%.16llx\n", serr);
+	dev_crit(&ctx->afu->dev, "PSL_FIR_SLICE_An: 0x%.16llx\n", fir_slice);
+	dev_crit(&ctx->afu->dev, "CXL_PSL_AFU_DEBUG_An: 0x%.16llx\n", afu_debug);
+
+	dev_crit(&ctx->afu->dev, "STOPPING CXL TRACE\n");
+	cxl_stop_trace(ctx->afu->adapter);
+
+	return cxl_ack_irq(ctx, 0, errstat);
+}
+
+irqreturn_t cxl_slice_irq_err(int irq, void *data)
+{
+	struct cxl_afu *afu = data;
+	u64 fir_slice, errstat, serr, afu_debug;
+
+	WARN(irq, "CXL SLICE ERROR interrupt %i\n", irq);
+
+	serr = cxl_p1n_read(afu, CXL_PSL_SERR_An);
+	fir_slice = cxl_p1n_read(afu, CXL_PSL_FIR_SLICE_An);
+	errstat = cxl_p2n_read(afu, CXL_PSL_ErrStat_An);
+	afu_debug = cxl_p1n_read(afu, CXL_AFU_DEBUG_An);
+	dev_crit(&afu->dev, "PSL_SERR_An: 0x%.16llx\n", serr);
+	dev_crit(&afu->dev, "PSL_FIR_SLICE_An: 0x%.16llx\n", fir_slice);
+	dev_crit(&afu->dev, "CXL_PSL_ErrStat_An: 0x%.16llx\n", errstat);
+	dev_crit(&afu->dev, "CXL_PSL_AFU_DEBUG_An: 0x%.16llx\n", afu_debug);
+
+	cxl_p1n_write(afu, CXL_PSL_SERR_An, serr);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t cxl_irq_err(int irq, void *data)
+{
+	struct cxl *adapter = data;
+	u64 fir1, fir2, err_ivte;
+
+	WARN(1, "CXL ERROR interrupt %i\n", irq);
+
+	err_ivte = cxl_p1_read(adapter, CXL_PSL_ErrIVTE);
+	dev_crit(&adapter->dev, "PSL_ErrIVTE: 0x%.16llx\n", err_ivte);
+
+	dev_crit(&adapter->dev, "STOPPING CXL TRACE\n");
+	cxl_stop_trace(adapter);
+
+	fir1 = cxl_p1_read(adapter, CXL_PSL_FIR1);
+	fir2 = cxl_p1_read(adapter, CXL_PSL_FIR2);
+
+	dev_crit(&adapter->dev, "PSL_FIR1: 0x%.16llx\nPSL_FIR2: 0x%.16llx\n", fir1, fir2);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t schedule_cxl_fault(struct cxl_context *ctx, u64 dsisr, u64 dar)
+{
+	ctx->dsisr = dsisr;
+	ctx->dar = dar;
+	schedule_work(&ctx->fault_work);
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t cxl_irq(int irq, void *data)
+{
+	struct cxl_context *ctx = data;
+	struct cxl_irq_info irq_info;
+	u64 dsisr, dar;
+	int result;
+
+	if ((result = cxl_get_irq(ctx, &irq_info))) {
+		WARN(1, "Unable to get CXL IRQ Info: %i\n", result);
+		return IRQ_HANDLED;
+	}
+
+	dsisr = irq_info.dsisr;
+	dar = irq_info.dar;
+
+	pr_devel("CXL interrupt %i for afu pe: %i DSISR: %#llx DAR: %#llx\n", irq, ctx->pe, dsisr, dar);
+
+	if (dsisr & CXL_PSL_DSISR_An_DS) {
+		/*
+		 * We don't inherently need to sleep to handle this, but we do
+		 * need to get a ref to the task's mm, which we can't do from
+		 * irq context without the potential for a deadlock since it
+		 * takes the task_lock. An alternate option would be to keep a
+		 * reference to the task's mm the entire time it has cxl open,
+		 * but to do that we need to solve the issue where we hold a
+		 * ref to the mm, but the mm can hold a ref to the fd after an
+		 * mmap preventing anything from being cleaned up.
+		 */
+		pr_devel("Scheduling segment miss handling for later pe: %i\n", ctx->pe);
+		return schedule_cxl_fault(ctx, dsisr, dar);
+	}
+
+	if (dsisr & CXL_PSL_DSISR_An_M)
+		pr_devel("CXL interrupt: PTE not found\n");
+	if (dsisr & CXL_PSL_DSISR_An_P)
+		pr_devel("CXL interrupt: Storage protection violation\n");
+	if (dsisr & CXL_PSL_DSISR_An_A)
+		pr_devel("CXL interrupt: AFU lock access to write through or cache inhibited storage\n");
+	if (dsisr & CXL_PSL_DSISR_An_S)
+		pr_devel("CXL interrupt: Access was afu_wr or afu_zero\n");
+	if (dsisr & CXL_PSL_DSISR_An_K)
+		pr_devel("CXL interrupt: Access not permitted by virtual page class key protection\n");
+
+	if (dsisr & CXL_PSL_DSISR_An_DM) {
+		/*
+		 * In some cases we might be able to handle the fault
+		 * immediately if hash_page would succeed, but we still need
+		 * the task's mm, which as above we can't get without a lock
+		 */
+		pr_devel("Scheduling page fault handling for later pe: %i\n", ctx->pe);
+		return schedule_cxl_fault(ctx, dsisr, dar);
+	}
+	if (dsisr & CXL_PSL_DSISR_An_ST)
+		WARN(1, "CXL interrupt: Segment Table PTE not found\n");
+	if (dsisr & CXL_PSL_DSISR_An_UR)
+		pr_devel("CXL interrupt: AURP PTE not found\n");
+	if (dsisr & CXL_PSL_DSISR_An_PE)
+		return handle_psl_slice_error(ctx, dsisr, irq_info.errstat);
+	if (dsisr & CXL_PSL_DSISR_An_AE) {
+		pr_devel("CXL interrupt: AFU Error %.llx\n", irq_info.afu_err);
+
+		if (ctx->pending_afu_err) {
+			/*
+			 * This shouldn't happen - the PSL treats these errors
+			 * as fatal and will have reset the AFU, so there's not
+			 * much point buffering multiple AFU errors.
+			 * OTOH if we DO ever see a storm of these come in it's
+			 * probably best that we log them somewhere:
+			 */
+			dev_err_ratelimited(&ctx->afu->dev, "CXL AFU Error "
+					    "undelivered to pe %i: %.llx\n",
+					    ctx->pe, irq_info.afu_err);
+		} else {
+			spin_lock(&ctx->lock);
+			ctx->afu_err = irq_info.afu_err;
+			ctx->pending_afu_err = 1;
+			spin_unlock(&ctx->lock);
+
+			wake_up_all(&ctx->wq);
+		}
+
+		cxl_ack_irq(ctx, CXL_PSL_TFC_An_A, 0);
+		return IRQ_HANDLED;
+	}
+	if (dsisr & CXL_PSL_DSISR_An_OC)
+		pr_devel("CXL interrupt: OS Context Warning\n");
+
+	WARN(1, "Unhandled CXL PSL IRQ\n");
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t cxl_irq_multiplexed(int irq, void *data)
+{
+	struct cxl_afu *afu = data;
+	struct cxl_context *ctx;
+	int ph = cxl_p2n_read(afu, CXL_PSL_PEHandle_An) & 0xffff;
+	int ret;
+
+	rcu_read_lock();
+	ctx = idr_find(&afu->contexts_idr, ph);
+	if (ctx) {
+		ret = cxl_irq(irq, ctx);
+		rcu_read_unlock();
+		return ret;
+	}
+	rcu_read_unlock();
+
+	WARN(1, "Unable to demultiplex CXL PSL IRQ\n");
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t cxl_irq_afu(int irq, void *data)
+{
+	struct cxl_context *ctx = data;
+	irq_hw_number_t hwirq = irqd_to_hwirq(irq_get_irq_data(irq));
+	int irq_off, afu_irq = 1;
+	__u16 range;
+	int r;
+
+	for (r = 1; r < CXL_IRQ_RANGES; r++) {
+		irq_off = hwirq - ctx->irqs.offset[r];
+		range = ctx->irqs.range[r];
+		if (irq_off >= 0 && irq_off < range) {
+			afu_irq += irq_off;
+			break;
+		}
+		afu_irq += range;
+	}
+	if (unlikely(r >= CXL_IRQ_RANGES)) {
+		WARN(1, "Recieved AFU IRQ out of range for pe %i (virq %i hwirq %lx)\n",
+		     ctx->pe, irq, hwirq);
+		return IRQ_HANDLED;
+	}
+
+	pr_devel("Received AFU interrupt %i for pe: %i (virq %i hwirq %lx)\n",
+	       afu_irq, ctx->pe, irq, hwirq);
+
+	if (unlikely(!ctx->irq_bitmap)) {
+		WARN(1, "Recieved AFU IRQ for context with no IRQ bitmap\n");
+		return IRQ_HANDLED;
+	}
+	spin_lock(&ctx->lock);
+	set_bit(afu_irq - 1, ctx->irq_bitmap);
+	ctx->pending_irq = true;
+	spin_unlock(&ctx->lock);
+
+	wake_up_all(&ctx->wq);
+
+	return IRQ_HANDLED;
+}
+
+unsigned int cxl_map_irq(struct cxl *adapter, irq_hw_number_t hwirq,
+			 irq_handler_t handler, void *cookie)
+{
+	unsigned int virq;
+	int result;
+
+	/* IRQ Domain? */
+	virq = irq_create_mapping(NULL, hwirq);
+	if (!virq) {
+		dev_warn(&adapter->dev, "cxl_map_irq: irq_create_mapping failed\n");
+		return 0;
+	}
+
+	cxl_setup_irq(adapter, hwirq, virq);
+
+	pr_devel("hwirq %#lx mapped to virq %u\n", hwirq, virq);
+
+	result = request_irq(virq, handler, 0, "cxl", cookie);
+	if (result) {
+		dev_warn(&adapter->dev, "cxl_map_irq: request_irq failed: %i\n", result);
+		return 0;
+	}
+
+	return virq;
+}
+
+void cxl_unmap_irq(unsigned int virq, void *cookie)
+{
+	free_irq(virq, cookie);
+	irq_dispose_mapping(virq);
+}
+
+static int cxl_register_one_irq(struct cxl *adapter,
+				irq_handler_t handler,
+				void *cookie,
+				irq_hw_number_t *dest_hwirq,
+				unsigned int *dest_virq)
+{
+	int hwirq, virq;
+
+	if ((hwirq = cxl_alloc_one_irq(adapter)) < 0)
+		return hwirq;
+
+	if (!(virq = cxl_map_irq(adapter, hwirq, handler, cookie)))
+		goto err;
+
+	*dest_hwirq = hwirq;
+	*dest_virq = virq;
+
+	return 0;
+
+err:
+	cxl_release_one_irq(adapter, hwirq);
+	return -ENOMEM;
+}
+
+int cxl_register_psl_err_irq(struct cxl *adapter)
+{
+	int rc;
+
+	if ((rc = cxl_register_one_irq(adapter, cxl_irq_err, adapter,
+				       &adapter->err_hwirq,
+				       &adapter->err_virq)))
+		return rc;
+
+	cxl_p1_write(adapter, CXL_PSL_ErrIVTE, adapter->err_hwirq & 0xffff);
+
+	return 0;
+}
+
+void cxl_release_psl_err_irq(struct cxl *adapter)
+{
+	cxl_p1_write(adapter, CXL_PSL_ErrIVTE, 0x0000000000000000);
+	cxl_unmap_irq(adapter->err_virq, adapter);
+	cxl_release_one_irq(adapter, adapter->err_hwirq);
+}
+
+int cxl_register_serr_irq(struct cxl_afu *afu)
+{
+	u64 serr;
+	int rc;
+
+	if ((rc = cxl_register_one_irq(afu->adapter, cxl_slice_irq_err, afu,
+				       &afu->serr_hwirq,
+				       &afu->serr_virq)))
+		return rc;
+
+	serr = cxl_p1n_read(afu, CXL_PSL_SERR_An);
+	serr = (serr & 0x00ffffffffff0000ULL) | (afu->serr_hwirq & 0xffff);
+	cxl_p1n_write(afu, CXL_PSL_SERR_An, serr);
+
+	return 0;
+}
+
+void cxl_release_serr_irq(struct cxl_afu *afu)
+{
+	cxl_p1n_write(afu, CXL_PSL_SERR_An, 0x0000000000000000);
+	cxl_unmap_irq(afu->serr_virq, afu);
+	cxl_release_one_irq(afu->adapter, afu->serr_hwirq);
+}
+
+int cxl_register_psl_irq(struct cxl_afu *afu)
+{
+	return cxl_register_one_irq(afu->adapter, cxl_irq_multiplexed, afu,
+			&afu->psl_hwirq, &afu->psl_virq);
+}
+
+void cxl_release_psl_irq(struct cxl_afu *afu)
+{
+	cxl_unmap_irq(afu->psl_virq, afu);
+	cxl_release_one_irq(afu->adapter, afu->psl_hwirq);
+}
+
+int afu_register_irqs(struct cxl_context *ctx, u32 count)
+{
+	irq_hw_number_t hwirq;
+	int rc, r, i;
+
+	if ((rc = cxl_alloc_irq_ranges(&ctx->irqs, ctx->afu->adapter, count)))
+		return rc;
+
+	/* Multiplexed PSL Interrupt */
+	ctx->irqs.offset[0] = ctx->afu->psl_hwirq;
+	ctx->irqs.range[0] = 1;
+
+	ctx->irq_count = count;
+	ctx->irq_bitmap = kcalloc(BITS_TO_LONGS(count),
+				  sizeof(*ctx->irq_bitmap), GFP_KERNEL);
+	if (!ctx->irq_bitmap)
+		return -ENOMEM;
+	for (r = 1; r < CXL_IRQ_RANGES; r++) {
+		hwirq = ctx->irqs.offset[r];
+		for (i = 0; i < ctx->irqs.range[r]; hwirq++, i++) {
+			cxl_map_irq(ctx->afu->adapter, hwirq,
+				     cxl_irq_afu, ctx);
+		}
+	}
+
+	return 0;
+}
+
+void afu_release_irqs(struct cxl_context *ctx)
+{
+	irq_hw_number_t hwirq;
+	unsigned int virq;
+	int r, i;
+
+	for (r = 1; r < CXL_IRQ_RANGES; r++) {
+		hwirq = ctx->irqs.offset[r];
+		for (i = 0; i < ctx->irqs.range[r]; hwirq++, i++) {
+			virq = irq_find_mapping(NULL, hwirq);
+			if (virq)
+				cxl_unmap_irq(virq, ctx);
+		}
+	}
+
+	cxl_release_irq_ranges(&ctx->irqs, ctx->afu->adapter);
+}

drivers/misc/cxl/main.c

@@ -0,0 +1,230 @@
+/*
+ * Copyright 2014 IBM Corp.
+ *
+ * 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.
+ */
+
+#include <linux/spinlock.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/mm.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/idr.h>
+#include <linux/pci.h>
+#include <asm/cputable.h>
+#include <misc/cxl.h>
+
+#include "cxl.h"
+
+static DEFINE_SPINLOCK(adapter_idr_lock);
+static DEFINE_IDR(cxl_adapter_idr);
+
+uint cxl_verbose;
+module_param_named(verbose, cxl_verbose, uint, 0600);
+MODULE_PARM_DESC(verbose, "Enable verbose dmesg output");
+
+static inline void _cxl_slbia(struct cxl_context *ctx, struct mm_struct *mm)
+{
+	struct task_struct *task;
+	unsigned long flags;
+	if (!(task = get_pid_task(ctx->pid, PIDTYPE_PID))) {
+		pr_devel("%s unable to get task %i\n",
+			 __func__, pid_nr(ctx->pid));
+		return;
+	}
+
+	if (task->mm != mm)
+		goto out_put;
+
+	pr_devel("%s matched mm - card: %i afu: %i pe: %i\n", __func__,
+		 ctx->afu->adapter->adapter_num, ctx->afu->slice, ctx->pe);
+
+	spin_lock_irqsave(&ctx->sste_lock, flags);
+	memset(ctx->sstp, 0, ctx->sst_size);
+	spin_unlock_irqrestore(&ctx->sste_lock, flags);
+	mb();
+	cxl_afu_slbia(ctx->afu);
+out_put:
+	put_task_struct(task);
+}
+
+static inline void cxl_slbia_core(struct mm_struct *mm)
+{
+	struct cxl *adapter;
+	struct cxl_afu *afu;
+	struct cxl_context *ctx;
+	int card, slice, id;
+
+	pr_devel("%s called\n", __func__);
+
+	spin_lock(&adapter_idr_lock);
+	idr_for_each_entry(&cxl_adapter_idr, adapter, card) {
+		/* XXX: Make this lookup faster with link from mm to ctx */
+		spin_lock(&adapter->afu_list_lock);
+		for (slice = 0; slice < adapter->slices; slice++) {
+			afu = adapter->afu[slice];
+			if (!afu->enabled)
+				continue;
+			rcu_read_lock();
+			idr_for_each_entry(&afu->contexts_idr, ctx, id)
+				_cxl_slbia(ctx, mm);
+			rcu_read_unlock();
+		}
+		spin_unlock(&adapter->afu_list_lock);
+	}
+	spin_unlock(&adapter_idr_lock);
+}
+
+static struct cxl_calls cxl_calls = {
+	.cxl_slbia = cxl_slbia_core,
+	.owner = THIS_MODULE,
+};
+
+int cxl_alloc_sst(struct cxl_context *ctx)
+{
+	unsigned long vsid;
+	u64 ea_mask, size, sstp0, sstp1;
+
+	sstp0 = 0;
+	sstp1 = 0;
+
+	ctx->sst_size = PAGE_SIZE;
+	ctx->sst_lru = 0;
+	ctx->sstp = (struct cxl_sste *)get_zeroed_page(GFP_KERNEL);
+	if (!ctx->sstp) {
+		pr_err("cxl_alloc_sst: Unable to allocate segment table\n");
+		return -ENOMEM;
+	}
+	pr_devel("SSTP allocated at 0x%p\n", ctx->sstp);
+
+	vsid  = get_kernel_vsid((u64)ctx->sstp, mmu_kernel_ssize) << 12;
+
+	sstp0 |= (u64)mmu_kernel_ssize << CXL_SSTP0_An_B_SHIFT;
+	sstp0 |= (SLB_VSID_KERNEL | mmu_psize_defs[mmu_linear_psize].sllp) << 50;
+
+	size = (((u64)ctx->sst_size >> 8) - 1) << CXL_SSTP0_An_SegTableSize_SHIFT;
+	if (unlikely(size & ~CXL_SSTP0_An_SegTableSize_MASK)) {
+		WARN(1, "Impossible segment table size\n");
+		return -EINVAL;
+	}
+	sstp0 |= size;
+
+	if (mmu_kernel_ssize == MMU_SEGSIZE_256M)
+		ea_mask = 0xfffff00ULL;
+	else
+		ea_mask = 0xffffffff00ULL;
+
+	sstp0 |=  vsid >>     (50-14);  /*   Top 14 bits of VSID */
+	sstp1 |= (vsid << (64-(50-14))) & ~ea_mask;
+	sstp1 |= (u64)ctx->sstp & ea_mask;
+	sstp1 |= CXL_SSTP1_An_V;
+
+	pr_devel("Looked up %#llx: slbfee. %#llx (ssize: %x, vsid: %#lx), copied to SSTP0: %#llx, SSTP1: %#llx\n",
+			(u64)ctx->sstp, (u64)ctx->sstp & ESID_MASK, mmu_kernel_ssize, vsid, sstp0, sstp1);
+
+	/* Store calculated sstp hardware points for use later */
+	ctx->sstp0 = sstp0;
+	ctx->sstp1 = sstp1;
+
+	return 0;
+}
+
+/* Find a CXL adapter by it's number and increase it's refcount */
+struct cxl *get_cxl_adapter(int num)
+{
+	struct cxl *adapter;
+
+	spin_lock(&adapter_idr_lock);
+	if ((adapter = idr_find(&cxl_adapter_idr, num)))
+		get_device(&adapter->dev);
+	spin_unlock(&adapter_idr_lock);
+
+	return adapter;
+}
+
+int cxl_alloc_adapter_nr(struct cxl *adapter)
+{
+	int i;
+
+	idr_preload(GFP_KERNEL);
+	spin_lock(&adapter_idr_lock);
+	i = idr_alloc(&cxl_adapter_idr, adapter, 0, 0, GFP_NOWAIT);
+	spin_unlock(&adapter_idr_lock);
+	idr_preload_end();
+	if (i < 0)
+		return i;
+
+	adapter->adapter_num = i;
+
+	return 0;
+}
+
+void cxl_remove_adapter_nr(struct cxl *adapter)
+{
+	idr_remove(&cxl_adapter_idr, adapter->adapter_num);
+}
+
+int cxl_afu_select_best_mode(struct cxl_afu *afu)
+{
+	if (afu->modes_supported & CXL_MODE_DIRECTED)
+		return cxl_afu_activate_mode(afu, CXL_MODE_DIRECTED);
+
+	if (afu->modes_supported & CXL_MODE_DEDICATED)
+		return cxl_afu_activate_mode(afu, CXL_MODE_DEDICATED);
+
+	dev_warn(&afu->dev, "No supported programming modes available\n");
+	/* We don't fail this so the user can inspect sysfs */
+	return 0;
+}
+
+static int __init init_cxl(void)
+{
+	int rc = 0;
+
+	if (!cpu_has_feature(CPU_FTR_HVMODE))
+		return -EPERM;
+
+	if ((rc = cxl_file_init()))
+		return rc;
+
+	cxl_debugfs_init();
+
+	if ((rc = register_cxl_calls(&cxl_calls)))
+		goto err;
+
+	if ((rc = pci_register_driver(&cxl_pci_driver)))
+		goto err1;
+
+	return 0;
+err1:
+	unregister_cxl_calls(&cxl_calls);
+err:
+	cxl_debugfs_exit();
+	cxl_file_exit();
+
+	return rc;
+}
+
+static void exit_cxl(void)
+{
+	pci_unregister_driver(&cxl_pci_driver);
+
+	cxl_debugfs_exit();
+	cxl_file_exit();
+	unregister_cxl_calls(&cxl_calls);
+}
+
+module_init(init_cxl);
+module_exit(exit_cxl);
+
+MODULE_DESCRIPTION("IBM Coherent Accelerator");
+MODULE_AUTHOR("Ian Munsie <imunsie@au1.ibm.com>");
+MODULE_LICENSE("GPL");

drivers/misc/cxl/native.c

@@ -0,0 +1,681 @@
+/*
+ * Copyright 2014 IBM Corp.
+ *
+ * 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.
+ */
+
+#include <linux/spinlock.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/mutex.h>
+#include <linux/mm.h>
+#include <linux/uaccess.h>
+#include <asm/synch.h>
+#include <misc/cxl.h>
+
+#include "cxl.h"
+
+static int afu_control(struct cxl_afu *afu, u64 command,
+		       u64 result, u64 mask, bool enabled)
+{
+	u64 AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
+	unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
+
+	spin_lock(&afu->afu_cntl_lock);
+	pr_devel("AFU command starting: %llx\n", command);
+
+	cxl_p2n_write(afu, CXL_AFU_Cntl_An, AFU_Cntl | command);
+
+	AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
+	while ((AFU_Cntl & mask) != result) {
+		if (time_after_eq(jiffies, timeout)) {
+			dev_warn(&afu->dev, "WARNING: AFU control timed out!\n");
+			spin_unlock(&afu->afu_cntl_lock);
+			return -EBUSY;
+		}
+		pr_devel_ratelimited("AFU control... (0x%.16llx)\n",
+				     AFU_Cntl | command);
+		cpu_relax();
+		AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
+	};
+	pr_devel("AFU command complete: %llx\n", command);
+	afu->enabled = enabled;
+	spin_unlock(&afu->afu_cntl_lock);
+
+	return 0;
+}
+
+static int afu_enable(struct cxl_afu *afu)
+{
+	pr_devel("AFU enable request\n");
+
+	return afu_control(afu, CXL_AFU_Cntl_An_E,
+			   CXL_AFU_Cntl_An_ES_Enabled,
+			   CXL_AFU_Cntl_An_ES_MASK, true);
+}
+
+int cxl_afu_disable(struct cxl_afu *afu)
+{
+	pr_devel("AFU disable request\n");
+
+	return afu_control(afu, 0, CXL_AFU_Cntl_An_ES_Disabled,
+			   CXL_AFU_Cntl_An_ES_MASK, false);
+}
+
+/* This will disable as well as reset */
+int cxl_afu_reset(struct cxl_afu *afu)
+{
+	pr_devel("AFU reset request\n");
+
+	return afu_control(afu, CXL_AFU_Cntl_An_RA,
+			   CXL_AFU_Cntl_An_RS_Complete | CXL_AFU_Cntl_An_ES_Disabled,
+			   CXL_AFU_Cntl_An_RS_MASK | CXL_AFU_Cntl_An_ES_MASK,
+			   false);
+}
+
+static int afu_check_and_enable(struct cxl_afu *afu)
+{
+	if (afu->enabled)
+		return 0;
+	return afu_enable(afu);
+}
+
+int cxl_psl_purge(struct cxl_afu *afu)
+{
+	u64 PSL_CNTL = cxl_p1n_read(afu, CXL_PSL_SCNTL_An);
+	u64 AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
+	u64 dsisr, dar;
+	u64 start, end;
+	unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
+
+	pr_devel("PSL purge request\n");
+
+	if ((AFU_Cntl & CXL_AFU_Cntl_An_ES_MASK) != CXL_AFU_Cntl_An_ES_Disabled) {
+		WARN(1, "psl_purge request while AFU not disabled!\n");
+		cxl_afu_disable(afu);
+	}
+
+	cxl_p1n_write(afu, CXL_PSL_SCNTL_An,
+		       PSL_CNTL | CXL_PSL_SCNTL_An_Pc);
+	start = local_clock();
+	PSL_CNTL = cxl_p1n_read(afu, CXL_PSL_SCNTL_An);
+	while ((PSL_CNTL &  CXL_PSL_SCNTL_An_Ps_MASK)
+			== CXL_PSL_SCNTL_An_Ps_Pending) {
+		if (time_after_eq(jiffies, timeout)) {
+			dev_warn(&afu->dev, "WARNING: PSL Purge timed out!\n");
+			return -EBUSY;
+		}
+		dsisr = cxl_p2n_read(afu, CXL_PSL_DSISR_An);
+		pr_devel_ratelimited("PSL purging... PSL_CNTL: 0x%.16llx  PSL_DSISR: 0x%.16llx\n", PSL_CNTL, dsisr);
+		if (dsisr & CXL_PSL_DSISR_TRANS) {
+			dar = cxl_p2n_read(afu, CXL_PSL_DAR_An);
+			dev_notice(&afu->dev, "PSL purge terminating pending translation, DSISR: 0x%.16llx, DAR: 0x%.16llx\n", dsisr, dar);
+			cxl_p2n_write(afu, CXL_PSL_TFC_An, CXL_PSL_TFC_An_AE);
+		} else if (dsisr) {
+			dev_notice(&afu->dev, "PSL purge acknowledging pending non-translation fault, DSISR: 0x%.16llx\n", dsisr);
+			cxl_p2n_write(afu, CXL_PSL_TFC_An, CXL_PSL_TFC_An_A);
+		} else {
+			cpu_relax();
+		}
+		PSL_CNTL = cxl_p1n_read(afu, CXL_PSL_SCNTL_An);
+	};
+	end = local_clock();
+	pr_devel("PSL purged in %lld ns\n", end - start);
+
+	cxl_p1n_write(afu, CXL_PSL_SCNTL_An,
+		       PSL_CNTL & ~CXL_PSL_SCNTL_An_Pc);
+	return 0;
+}
+
+static int spa_max_procs(int spa_size)
+{
+	/*
+	 * From the CAIA:
+	 *    end_of_SPA_area = SPA_Base + ((n+4) * 128) + (( ((n*8) + 127) >> 7) * 128) + 255
+	 * Most of that junk is really just an overly-complicated way of saying
+	 * the last 256 bytes are __aligned(128), so it's really:
+	 *    end_of_SPA_area = end_of_PSL_queue_area + __aligned(128) 255
+	 * and
+	 *    end_of_PSL_queue_area = SPA_Base + ((n+4) * 128) + (n*8) - 1
+	 * so
+	 *    sizeof(SPA) = ((n+4) * 128) + (n*8) + __aligned(128) 256
+	 * Ignore the alignment (which is safe in this case as long as we are
+	 * careful with our rounding) and solve for n:
+	 */
+	return ((spa_size / 8) - 96) / 17;
+}
+
+static int alloc_spa(struct cxl_afu *afu)
+{
+	u64 spap;
+
+	/* Work out how many pages to allocate */
+	afu->spa_order = 0;
+	do {
+		afu->spa_order++;
+		afu->spa_size = (1 << afu->spa_order) * PAGE_SIZE;
+		afu->spa_max_procs = spa_max_procs(afu->spa_size);
+	} while (afu->spa_max_procs < afu->num_procs);
+
+	WARN_ON(afu->spa_size > 0x100000); /* Max size supported by the hardware */
+
+	if (!(afu->spa = (struct cxl_process_element *)
+	      __get_free_pages(GFP_KERNEL | __GFP_ZERO, afu->spa_order))) {
+		pr_err("cxl_alloc_spa: Unable to allocate scheduled process area\n");
+		return -ENOMEM;
+	}
+	pr_devel("spa pages: %i afu->spa_max_procs: %i   afu->num_procs: %i\n",
+		 1<<afu->spa_order, afu->spa_max_procs, afu->num_procs);
+
+	afu->sw_command_status = (__be64 *)((char *)afu->spa +
+					    ((afu->spa_max_procs + 3) * 128));
+
+	spap = virt_to_phys(afu->spa) & CXL_PSL_SPAP_Addr;
+	spap |= ((afu->spa_size >> (12 - CXL_PSL_SPAP_Size_Shift)) - 1) & CXL_PSL_SPAP_Size;
+	spap |= CXL_PSL_SPAP_V;
+	pr_devel("cxl: SPA allocated at 0x%p. Max processes: %i, sw_command_status: 0x%p CXL_PSL_SPAP_An=0x%016llx\n", afu->spa, afu->spa_max_procs, afu->sw_command_status, spap);
+	cxl_p1n_write(afu, CXL_PSL_SPAP_An, spap);
+
+	return 0;
+}
+
+static void release_spa(struct cxl_afu *afu)
+{
+	free_pages((unsigned long) afu->spa, afu->spa_order);
+}
+
+int cxl_tlb_slb_invalidate(struct cxl *adapter)
+{
+	unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
+
+	pr_devel("CXL adapter wide TLBIA & SLBIA\n");
+
+	cxl_p1_write(adapter, CXL_PSL_AFUSEL, CXL_PSL_AFUSEL_A);
+
+	cxl_p1_write(adapter, CXL_PSL_TLBIA, CXL_TLB_SLB_IQ_ALL);
+	while (cxl_p1_read(adapter, CXL_PSL_TLBIA) & CXL_TLB_SLB_P) {
+		if (time_after_eq(jiffies, timeout)) {
+			dev_warn(&adapter->dev, "WARNING: CXL adapter wide TLBIA timed out!\n");
+			return -EBUSY;
+		}
+		cpu_relax();
+	}
+
+	cxl_p1_write(adapter, CXL_PSL_SLBIA, CXL_TLB_SLB_IQ_ALL);
+	while (cxl_p1_read(adapter, CXL_PSL_SLBIA) & CXL_TLB_SLB_P) {
+		if (time_after_eq(jiffies, timeout)) {
+			dev_warn(&adapter->dev, "WARNING: CXL adapter wide SLBIA timed out!\n");
+			return -EBUSY;
+		}
+		cpu_relax();
+	}
+	return 0;
+}
+
+int cxl_afu_slbia(struct cxl_afu *afu)
+{
+	unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
+
+	pr_devel("cxl_afu_slbia issuing SLBIA command\n");
+	cxl_p2n_write(afu, CXL_SLBIA_An, CXL_TLB_SLB_IQ_ALL);
+	while (cxl_p2n_read(afu, CXL_SLBIA_An) & CXL_TLB_SLB_P) {
+		if (time_after_eq(jiffies, timeout)) {
+			dev_warn(&afu->dev, "WARNING: CXL AFU SLBIA timed out!\n");
+			return -EBUSY;
+		}
+		cpu_relax();
+	}
+	return 0;
+}
+
+static int cxl_write_sstp(struct cxl_afu *afu, u64 sstp0, u64 sstp1)
+{
+	int rc;
+
+	/* 1. Disable SSTP by writing 0 to SSTP1[V] */
+	cxl_p2n_write(afu, CXL_SSTP1_An, 0);
+
+	/* 2. Invalidate all SLB entries */
+	if ((rc = cxl_afu_slbia(afu)))
+		return rc;
+
+	/* 3. Set SSTP0_An */
+	cxl_p2n_write(afu, CXL_SSTP0_An, sstp0);
+
+	/* 4. Set SSTP1_An */
+	cxl_p2n_write(afu, CXL_SSTP1_An, sstp1);
+
+	return 0;
+}
+
+/* Using per slice version may improve performance here. (ie. SLBIA_An) */
+static void slb_invalid(struct cxl_context *ctx)
+{
+	struct cxl *adapter = ctx->afu->adapter;
+	u64 slbia;
+
+	WARN_ON(!mutex_is_locked(&ctx->afu->spa_mutex));
+
+	cxl_p1_write(adapter, CXL_PSL_LBISEL,
+			((u64)be32_to_cpu(ctx->elem->common.pid) << 32) |
+			be32_to_cpu(ctx->elem->lpid));
+	cxl_p1_write(adapter, CXL_PSL_SLBIA, CXL_TLB_SLB_IQ_LPIDPID);
+
+	while (1) {
+		slbia = cxl_p1_read(adapter, CXL_PSL_SLBIA);
+		if (!(slbia & CXL_TLB_SLB_P))
+			break;
+		cpu_relax();
+	}
+}
+
+static int do_process_element_cmd(struct cxl_context *ctx,
+				  u64 cmd, u64 pe_state)
+{
+	u64 state;
+	unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
+
+	WARN_ON(!ctx->afu->enabled);
+
+	ctx->elem->software_state = cpu_to_be32(pe_state);
+	smp_wmb();
+	*(ctx->afu->sw_command_status) = cpu_to_be64(cmd | 0 | ctx->pe);
+	smp_mb();
+	cxl_p1n_write(ctx->afu, CXL_PSL_LLCMD_An, cmd | ctx->pe);
+	while (1) {
+		if (time_after_eq(jiffies, timeout)) {
+			dev_warn(&ctx->afu->dev, "WARNING: Process Element Command timed out!\n");
+			return -EBUSY;
+		}
+		state = be64_to_cpup(ctx->afu->sw_command_status);
+		if (state == ~0ULL) {
+			pr_err("cxl: Error adding process element to AFU\n");
+			return -1;
+		}
+		if ((state & (CXL_SPA_SW_CMD_MASK | CXL_SPA_SW_STATE_MASK  | CXL_SPA_SW_LINK_MASK)) ==
+		    (cmd | (cmd >> 16) | ctx->pe))
+			break;
+		/*
+		 * The command won't finish in the PSL if there are
+		 * outstanding DSIs.  Hence we need to yield here in
+		 * case there are outstanding DSIs that we need to
+		 * service.  Tuning possiblity: we could wait for a
+		 * while before sched
+		 */
+		schedule();
+
+	}
+	return 0;
+}
+
+static int add_process_element(struct cxl_context *ctx)
+{
+	int rc = 0;
+
+	mutex_lock(&ctx->afu->spa_mutex);
+	pr_devel("%s Adding pe: %i started\n", __func__, ctx->pe);
+	if (!(rc = do_process_element_cmd(ctx, CXL_SPA_SW_CMD_ADD, CXL_PE_SOFTWARE_STATE_V)))
+		ctx->pe_inserted = true;
+	pr_devel("%s Adding pe: %i finished\n", __func__, ctx->pe);
+	mutex_unlock(&ctx->afu->spa_mutex);
+	return rc;
+}
+
+static int terminate_process_element(struct cxl_context *ctx)
+{
+	int rc = 0;
+
+	/* fast path terminate if it's already invalid */
+	if (!(ctx->elem->software_state & cpu_to_be32(CXL_PE_SOFTWARE_STATE_V)))
+		return rc;
+
+	mutex_lock(&ctx->afu->spa_mutex);
+	pr_devel("%s Terminate pe: %i started\n", __func__, ctx->pe);
+	rc = do_process_element_cmd(ctx, CXL_SPA_SW_CMD_TERMINATE,
+				    CXL_PE_SOFTWARE_STATE_V | CXL_PE_SOFTWARE_STATE_T);
+	ctx->elem->software_state = 0;	/* Remove Valid bit */
+	pr_devel("%s Terminate pe: %i finished\n", __func__, ctx->pe);
+	mutex_unlock(&ctx->afu->spa_mutex);
+	return rc;
+}
+
+static int remove_process_element(struct cxl_context *ctx)
+{
+	int rc = 0;
+
+	mutex_lock(&ctx->afu->spa_mutex);
+	pr_devel("%s Remove pe: %i started\n", __func__, ctx->pe);
+	if (!(rc = do_process_element_cmd(ctx, CXL_SPA_SW_CMD_REMOVE, 0)))
+		ctx->pe_inserted = false;
+	slb_invalid(ctx);
+	pr_devel("%s Remove pe: %i finished\n", __func__, ctx->pe);
+	mutex_unlock(&ctx->afu->spa_mutex);
+
+	return rc;
+}
+
+
+static void assign_psn_space(struct cxl_context *ctx)
+{
+	if (!ctx->afu->pp_size || ctx->master) {
+		ctx->psn_phys = ctx->afu->psn_phys;
+		ctx->psn_size = ctx->afu->adapter->ps_size;
+	} else {
+		ctx->psn_phys = ctx->afu->psn_phys +
+			(ctx->afu->pp_offset + ctx->afu->pp_size * ctx->pe);
+		ctx->psn_size = ctx->afu->pp_size;
+	}
+}
+
+static int activate_afu_directed(struct cxl_afu *afu)
+{
+	int rc;
+
+	dev_info(&afu->dev, "Activating AFU directed mode\n");
+
+	if (alloc_spa(afu))
+		return -ENOMEM;
+
+	cxl_p1n_write(afu, CXL_PSL_SCNTL_An, CXL_PSL_SCNTL_An_PM_AFU);
+	cxl_p1n_write(afu, CXL_PSL_AMOR_An, 0xFFFFFFFFFFFFFFFFULL);
+	cxl_p1n_write(afu, CXL_PSL_ID_An, CXL_PSL_ID_An_F | CXL_PSL_ID_An_L);
+
+	afu->current_mode = CXL_MODE_DIRECTED;
+	afu->num_procs = afu->max_procs_virtualised;
+
+	if ((rc = cxl_chardev_m_afu_add(afu)))
+		return rc;
+
+	if ((rc = cxl_sysfs_afu_m_add(afu)))
+		goto err;
+
+	if ((rc = cxl_chardev_s_afu_add(afu)))
+		goto err1;
+
+	return 0;
+err1:
+	cxl_sysfs_afu_m_remove(afu);
+err:
+	cxl_chardev_afu_remove(afu);
+	return rc;
+}
+
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+#define set_endian(sr) ((sr) |= CXL_PSL_SR_An_LE)
+#else
+#define set_endian(sr) ((sr) &= ~(CXL_PSL_SR_An_LE))
+#endif
+
+static int attach_afu_directed(struct cxl_context *ctx, u64 wed, u64 amr)
+{
+	u64 sr;
+	int r, result;
+
+	assign_psn_space(ctx);
+
+	ctx->elem->ctxtime = 0; /* disable */
+	ctx->elem->lpid = cpu_to_be32(mfspr(SPRN_LPID));
+	ctx->elem->haurp = 0; /* disable */
+	ctx->elem->sdr = cpu_to_be64(mfspr(SPRN_SDR1));
+
+	sr = 0;
+	if (ctx->master)
+		sr |= CXL_PSL_SR_An_MP;
+	if (mfspr(SPRN_LPCR) & LPCR_TC)
+		sr |= CXL_PSL_SR_An_TC;
+	/* HV=0, PR=1, R=1 for userspace
+	 * For kernel contexts: this would need to change
+	 */
+	sr |= CXL_PSL_SR_An_PR | CXL_PSL_SR_An_R;
+	set_endian(sr);
+	sr &= ~(CXL_PSL_SR_An_HV);
+	if (!test_tsk_thread_flag(current, TIF_32BIT))
+		sr |= CXL_PSL_SR_An_SF;
+	ctx->elem->common.pid = cpu_to_be32(current->pid);
+	ctx->elem->common.tid = 0;
+	ctx->elem->sr = cpu_to_be64(sr);
+
+	ctx->elem->common.csrp = 0; /* disable */
+	ctx->elem->common.aurp0 = 0; /* disable */
+	ctx->elem->common.aurp1 = 0; /* disable */
+
+	cxl_prefault(ctx, wed);
+
+	ctx->elem->common.sstp0 = cpu_to_be64(ctx->sstp0);
+	ctx->elem->common.sstp1 = cpu_to_be64(ctx->sstp1);
+
+	for (r = 0; r < CXL_IRQ_RANGES; r++) {
+		ctx->elem->ivte_offsets[r] = cpu_to_be16(ctx->irqs.offset[r]);
+		ctx->elem->ivte_ranges[r] = cpu_to_be16(ctx->irqs.range[r]);
+	}
+
+	ctx->elem->common.amr = cpu_to_be64(amr);
+	ctx->elem->common.wed = cpu_to_be64(wed);
+
+	/* first guy needs to enable */
+	if ((result = afu_check_and_enable(ctx->afu)))
+		return result;
+
+	add_process_element(ctx);
+
+	return 0;
+}
+
+static int deactivate_afu_directed(struct cxl_afu *afu)
+{
+	dev_info(&afu->dev, "Deactivating AFU directed mode\n");
+
+	afu->current_mode = 0;
+	afu->num_procs = 0;
+
+	cxl_sysfs_afu_m_remove(afu);
+	cxl_chardev_afu_remove(afu);
+
+	cxl_afu_reset(afu);
+	cxl_afu_disable(afu);
+	cxl_psl_purge(afu);
+
+	release_spa(afu);
+
+	return 0;
+}
+
+static int activate_dedicated_process(struct cxl_afu *afu)
+{
+	dev_info(&afu->dev, "Activating dedicated process mode\n");
+
+	cxl_p1n_write(afu, CXL_PSL_SCNTL_An, CXL_PSL_SCNTL_An_PM_Process);
+
+	cxl_p1n_write(afu, CXL_PSL_CtxTime_An, 0); /* disable */
+	cxl_p1n_write(afu, CXL_PSL_SPAP_An, 0);    /* disable */
+	cxl_p1n_write(afu, CXL_PSL_AMOR_An, 0xFFFFFFFFFFFFFFFFULL);
+	cxl_p1n_write(afu, CXL_PSL_LPID_An, mfspr(SPRN_LPID));
+	cxl_p1n_write(afu, CXL_HAURP_An, 0);       /* disable */
+	cxl_p1n_write(afu, CXL_PSL_SDR_An, mfspr(SPRN_SDR1));
+
+	cxl_p2n_write(afu, CXL_CSRP_An, 0);        /* disable */
+	cxl_p2n_write(afu, CXL_AURP0_An, 0);       /* disable */
+	cxl_p2n_write(afu, CXL_AURP1_An, 0);       /* disable */
+
+	afu->current_mode = CXL_MODE_DEDICATED;
+	afu->num_procs = 1;
+
+	return cxl_chardev_d_afu_add(afu);
+}
+
+static int attach_dedicated(struct cxl_context *ctx, u64 wed, u64 amr)
+{
+	struct cxl_afu *afu = ctx->afu;
+	u64 sr;
+	int rc;
+
+	sr = 0;
+	set_endian(sr);
+	if (ctx->master)
+		sr |= CXL_PSL_SR_An_MP;
+	if (mfspr(SPRN_LPCR) & LPCR_TC)
+		sr |= CXL_PSL_SR_An_TC;
+	sr |= CXL_PSL_SR_An_PR | CXL_PSL_SR_An_R;
+	if (!test_tsk_thread_flag(current, TIF_32BIT))
+		sr |= CXL_PSL_SR_An_SF;
+	cxl_p2n_write(afu, CXL_PSL_PID_TID_An, (u64)current->pid << 32);
+	cxl_p1n_write(afu, CXL_PSL_SR_An, sr);
+
+	if ((rc = cxl_write_sstp(afu, ctx->sstp0, ctx->sstp1)))
+		return rc;
+
+	cxl_prefault(ctx, wed);
+
+	cxl_p1n_write(afu, CXL_PSL_IVTE_Offset_An,
+		       (((u64)ctx->irqs.offset[0] & 0xffff) << 48) |
+		       (((u64)ctx->irqs.offset[1] & 0xffff) << 32) |
+		       (((u64)ctx->irqs.offset[2] & 0xffff) << 16) |
+			((u64)ctx->irqs.offset[3] & 0xffff));
+	cxl_p1n_write(afu, CXL_PSL_IVTE_Limit_An, (u64)
+		       (((u64)ctx->irqs.range[0] & 0xffff) << 48) |
+		       (((u64)ctx->irqs.range[1] & 0xffff) << 32) |
+		       (((u64)ctx->irqs.range[2] & 0xffff) << 16) |
+			((u64)ctx->irqs.range[3] & 0xffff));
+
+	cxl_p2n_write(afu, CXL_PSL_AMR_An, amr);
+
+	/* master only context for dedicated */
+	assign_psn_space(ctx);
+
+	if ((rc = cxl_afu_reset(afu)))
+		return rc;
+
+	cxl_p2n_write(afu, CXL_PSL_WED_An, wed);
+
+	return afu_enable(afu);
+}
+
+static int deactivate_dedicated_process(struct cxl_afu *afu)
+{
+	dev_info(&afu->dev, "Deactivating dedicated process mode\n");
+
+	afu->current_mode = 0;
+	afu->num_procs = 0;
+
+	cxl_chardev_afu_remove(afu);
+
+	return 0;
+}
+
+int _cxl_afu_deactivate_mode(struct cxl_afu *afu, int mode)
+{
+	if (mode == CXL_MODE_DIRECTED)
+		return deactivate_afu_directed(afu);
+	if (mode == CXL_MODE_DEDICATED)
+		return deactivate_dedicated_process(afu);
+	return 0;
+}
+
+int cxl_afu_deactivate_mode(struct cxl_afu *afu)
+{
+	return _cxl_afu_deactivate_mode(afu, afu->current_mode);
+}
+
+int cxl_afu_activate_mode(struct cxl_afu *afu, int mode)
+{
+	if (!mode)
+		return 0;
+	if (!(mode & afu->modes_supported))
+		return -EINVAL;
+
+	if (mode == CXL_MODE_DIRECTED)
+		return activate_afu_directed(afu);
+	if (mode == CXL_MODE_DEDICATED)
+		return activate_dedicated_process(afu);
+
+	return -EINVAL;
+}
+
+int cxl_attach_process(struct cxl_context *ctx, bool kernel, u64 wed, u64 amr)
+{
+	ctx->kernel = kernel;
+	if (ctx->afu->current_mode == CXL_MODE_DIRECTED)
+		return attach_afu_directed(ctx, wed, amr);
+
+	if (ctx->afu->current_mode == CXL_MODE_DEDICATED)
+		return attach_dedicated(ctx, wed, amr);
+
+	return -EINVAL;
+}
+
+static inline int detach_process_native_dedicated(struct cxl_context *ctx)
+{
+	cxl_afu_reset(ctx->afu);
+	cxl_afu_disable(ctx->afu);
+	cxl_psl_purge(ctx->afu);
+	return 0;
+}
+
+static inline int detach_process_native_afu_directed(struct cxl_context *ctx)
+{
+	if (!ctx->pe_inserted)
+		return 0;
+	if (terminate_process_element(ctx))
+		return -1;
+	if (remove_process_element(ctx))
+		return -1;
+
+	return 0;
+}
+
+int cxl_detach_process(struct cxl_context *ctx)
+{
+	if (ctx->afu->current_mode == CXL_MODE_DEDICATED)
+		return detach_process_native_dedicated(ctx);
+
+	return detach_process_native_afu_directed(ctx);
+}
+
+int cxl_get_irq(struct cxl_context *ctx, struct cxl_irq_info *info)
+{
+	u64 pidtid;
+
+	info->dsisr = cxl_p2n_read(ctx->afu, CXL_PSL_DSISR_An);
+	info->dar = cxl_p2n_read(ctx->afu, CXL_PSL_DAR_An);
+	info->dsr = cxl_p2n_read(ctx->afu, CXL_PSL_DSR_An);
+	pidtid = cxl_p2n_read(ctx->afu, CXL_PSL_PID_TID_An);
+	info->pid = pidtid >> 32;
+	info->tid = pidtid & 0xffffffff;
+	info->afu_err = cxl_p2n_read(ctx->afu, CXL_AFU_ERR_An);
+	info->errstat = cxl_p2n_read(ctx->afu, CXL_PSL_ErrStat_An);
+
+	return 0;
+}
+
+static void recover_psl_err(struct cxl_afu *afu, u64 errstat)
+{
+	u64 dsisr;
+
+	pr_devel("RECOVERING FROM PSL ERROR... (0x%.16llx)\n", errstat);
+
+	/* Clear PSL_DSISR[PE] */
+	dsisr = cxl_p2n_read(afu, CXL_PSL_DSISR_An);
+	cxl_p2n_write(afu, CXL_PSL_DSISR_An, dsisr & ~CXL_PSL_DSISR_An_PE);
+
+	/* Write 1s to clear error status bits */
+	cxl_p2n_write(afu, CXL_PSL_ErrStat_An, errstat);
+}
+
+int cxl_ack_irq(struct cxl_context *ctx, u64 tfc, u64 psl_reset_mask)
+{
+	if (tfc)
+		cxl_p2n_write(ctx->afu, CXL_PSL_TFC_An, tfc);
+	if (psl_reset_mask)
+		recover_psl_err(ctx->afu, psl_reset_mask);
+
+	return 0;
+}
+
+int cxl_check_error(struct cxl_afu *afu)
+{
+	return (cxl_p1n_read(afu, CXL_PSL_SCNTL_An) == ~0ULL);
+}

drivers/misc/cxl/sysfs.c

@@ -0,0 +1,385 @@
+/*
+ * Copyright 2014 IBM Corp.
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/sysfs.h>
+
+#include "cxl.h"
+
+#define to_afu_chardev_m(d) dev_get_drvdata(d)
+
+/*********  Adapter attributes  **********************************************/
+
+static ssize_t caia_version_show(struct device *device,
+				 struct device_attribute *attr,
+				 char *buf)
+{
+	struct cxl *adapter = to_cxl_adapter(device);
+
+	return scnprintf(buf, PAGE_SIZE, "%i.%i\n", adapter->caia_major,
+			 adapter->caia_minor);
+}
+
+static ssize_t psl_revision_show(struct device *device,
+				 struct device_attribute *attr,
+				 char *buf)
+{
+	struct cxl *adapter = to_cxl_adapter(device);
+
+	return scnprintf(buf, PAGE_SIZE, "%i\n", adapter->psl_rev);
+}
+
+static ssize_t base_image_show(struct device *device,
+			       struct device_attribute *attr,
+			       char *buf)
+{
+	struct cxl *adapter = to_cxl_adapter(device);
+
+	return scnprintf(buf, PAGE_SIZE, "%i\n", adapter->base_image);
+}
+
+static ssize_t image_loaded_show(struct device *device,
+				 struct device_attribute *attr,
+				 char *buf)
+{
+	struct cxl *adapter = to_cxl_adapter(device);
+
+	if (adapter->user_image_loaded)
+		return scnprintf(buf, PAGE_SIZE, "user\n");
+	return scnprintf(buf, PAGE_SIZE, "factory\n");
+}
+
+static struct device_attribute adapter_attrs[] = {
+	__ATTR_RO(caia_version),
+	__ATTR_RO(psl_revision),
+	__ATTR_RO(base_image),
+	__ATTR_RO(image_loaded),
+};
+
+
+/*********  AFU master specific attributes  **********************************/
+
+static ssize_t mmio_size_show_master(struct device *device,
+				     struct device_attribute *attr,
+				     char *buf)
+{
+	struct cxl_afu *afu = to_afu_chardev_m(device);
+
+	return scnprintf(buf, PAGE_SIZE, "%llu\n", afu->adapter->ps_size);
+}
+
+static ssize_t pp_mmio_off_show(struct device *device,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct cxl_afu *afu = to_afu_chardev_m(device);
+
+	return scnprintf(buf, PAGE_SIZE, "%llu\n", afu->pp_offset);
+}
+
+static ssize_t pp_mmio_len_show(struct device *device,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct cxl_afu *afu = to_afu_chardev_m(device);
+
+	return scnprintf(buf, PAGE_SIZE, "%llu\n", afu->pp_size);
+}
+
+static struct device_attribute afu_master_attrs[] = {
+	__ATTR(mmio_size, S_IRUGO, mmio_size_show_master, NULL),
+	__ATTR_RO(pp_mmio_off),
+	__ATTR_RO(pp_mmio_len),
+};
+
+
+/*********  AFU attributes  **************************************************/
+
+static ssize_t mmio_size_show(struct device *device,
+			      struct device_attribute *attr,
+			      char *buf)
+{
+	struct cxl_afu *afu = to_cxl_afu(device);
+
+	if (afu->pp_size)
+		return scnprintf(buf, PAGE_SIZE, "%llu\n", afu->pp_size);
+	return scnprintf(buf, PAGE_SIZE, "%llu\n", afu->adapter->ps_size);
+}
+
+static ssize_t reset_store_afu(struct device *device,
+			       struct device_attribute *attr,
+			       const char *buf, size_t count)
+{
+	struct cxl_afu *afu = to_cxl_afu(device);
+	int rc;
+
+	/* Not safe to reset if it is currently in use */
+	mutex_lock(&afu->contexts_lock);
+	if (!idr_is_empty(&afu->contexts_idr)) {
+		rc = -EBUSY;
+		goto err;
+	}
+
+	if ((rc = cxl_afu_reset(afu)))
+		goto err;
+
+	rc = count;
+err:
+	mutex_unlock(&afu->contexts_lock);
+	return rc;
+}
+
+static ssize_t irqs_min_show(struct device *device,
+			     struct device_attribute *attr,
+			     char *buf)
+{
+	struct cxl_afu *afu = to_cxl_afu(device);
+
+	return scnprintf(buf, PAGE_SIZE, "%i\n", afu->pp_irqs);
+}
+
+static ssize_t irqs_max_show(struct device *device,
+				  struct device_attribute *attr,
+				  char *buf)
+{
+	struct cxl_afu *afu = to_cxl_afu(device);
+
+	return scnprintf(buf, PAGE_SIZE, "%i\n", afu->irqs_max);
+}
+
+static ssize_t irqs_max_store(struct device *device,
+				  struct device_attribute *attr,
+				  const char *buf, size_t count)
+{
+	struct cxl_afu *afu = to_cxl_afu(device);
+	ssize_t ret;
+	int irqs_max;
+
+	ret = sscanf(buf, "%i", &irqs_max);
+	if (ret != 1)
+		return -EINVAL;
+
+	if (irqs_max < afu->pp_irqs)
+		return -EINVAL;
+
+	if (irqs_max > afu->adapter->user_irqs)
+		return -EINVAL;
+
+	afu->irqs_max = irqs_max;
+	return count;
+}
+
+static ssize_t modes_supported_show(struct device *device,
+				    struct device_attribute *attr, char *buf)
+{
+	struct cxl_afu *afu = to_cxl_afu(device);
+	char *p = buf, *end = buf + PAGE_SIZE;
+
+	if (afu->modes_supported & CXL_MODE_DEDICATED)
+		p += scnprintf(p, end - p, "dedicated_process\n");
+	if (afu->modes_supported & CXL_MODE_DIRECTED)
+		p += scnprintf(p, end - p, "afu_directed\n");
+	return (p - buf);
+}
+
+static ssize_t prefault_mode_show(struct device *device,
+				  struct device_attribute *attr,
+				  char *buf)
+{
+	struct cxl_afu *afu = to_cxl_afu(device);
+
+	switch (afu->prefault_mode) {
+	case CXL_PREFAULT_WED:
+		return scnprintf(buf, PAGE_SIZE, "work_element_descriptor\n");
+	case CXL_PREFAULT_ALL:
+		return scnprintf(buf, PAGE_SIZE, "all\n");
+	default:
+		return scnprintf(buf, PAGE_SIZE, "none\n");
+	}
+}
+
+static ssize_t prefault_mode_store(struct device *device,
+			  struct device_attribute *attr,
+			  const char *buf, size_t count)
+{
+	struct cxl_afu *afu = to_cxl_afu(device);
+	enum prefault_modes mode = -1;
+
+	if (!strncmp(buf, "work_element_descriptor", 23))
+		mode = CXL_PREFAULT_WED;
+	if (!strncmp(buf, "all", 3))
+		mode = CXL_PREFAULT_ALL;
+	if (!strncmp(buf, "none", 4))
+		mode = CXL_PREFAULT_NONE;
+
+	if (mode == -1)
+		return -EINVAL;
+
+	afu->prefault_mode = mode;
+	return count;
+}
+
+static ssize_t mode_show(struct device *device,
+			 struct device_attribute *attr,
+			 char *buf)
+{
+	struct cxl_afu *afu = to_cxl_afu(device);
+
+	if (afu->current_mode == CXL_MODE_DEDICATED)
+		return scnprintf(buf, PAGE_SIZE, "dedicated_process\n");
+	if (afu->current_mode == CXL_MODE_DIRECTED)
+		return scnprintf(buf, PAGE_SIZE, "afu_directed\n");
+	return scnprintf(buf, PAGE_SIZE, "none\n");
+}
+
+static ssize_t mode_store(struct device *device, struct device_attribute *attr,
+			  const char *buf, size_t count)
+{
+	struct cxl_afu *afu = to_cxl_afu(device);
+	int old_mode, mode = -1;
+	int rc = -EBUSY;
+
+	/* can't change this if we have a user */
+	mutex_lock(&afu->contexts_lock);
+	if (!idr_is_empty(&afu->contexts_idr))
+		goto err;
+
+	if (!strncmp(buf, "dedicated_process", 17))
+		mode = CXL_MODE_DEDICATED;
+	if (!strncmp(buf, "afu_directed", 12))
+		mode = CXL_MODE_DIRECTED;
+	if (!strncmp(buf, "none", 4))
+		mode = 0;
+
+	if (mode == -1) {
+		rc = -EINVAL;
+		goto err;
+	}
+
+	/*
+	 * cxl_afu_deactivate_mode needs to be done outside the lock, prevent
+	 * other contexts coming in before we are ready:
+	 */
+	old_mode = afu->current_mode;
+	afu->current_mode = 0;
+	afu->num_procs = 0;
+
+	mutex_unlock(&afu->contexts_lock);
+
+	if ((rc = _cxl_afu_deactivate_mode(afu, old_mode)))
+		return rc;
+	if ((rc = cxl_afu_activate_mode(afu, mode)))
+		return rc;
+
+	return count;
+err:
+	mutex_unlock(&afu->contexts_lock);
+	return rc;
+}
+
+static ssize_t api_version_show(struct device *device,
+				struct device_attribute *attr,
+				char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%i\n", CXL_API_VERSION);
+}
+
+static ssize_t api_version_compatible_show(struct device *device,
+					   struct device_attribute *attr,
+					   char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%i\n", CXL_API_VERSION_COMPATIBLE);
+}
+
+static struct device_attribute afu_attrs[] = {
+	__ATTR_RO(mmio_size),
+	__ATTR_RO(irqs_min),
+	__ATTR_RW(irqs_max),
+	__ATTR_RO(modes_supported),
+	__ATTR_RW(mode),
+	__ATTR_RW(prefault_mode),
+	__ATTR_RO(api_version),
+	__ATTR_RO(api_version_compatible),
+	__ATTR(reset, S_IWUSR, NULL, reset_store_afu),
+};
+
+
+
+int cxl_sysfs_adapter_add(struct cxl *adapter)
+{
+	int i, rc;
+
+	for (i = 0; i < ARRAY_SIZE(adapter_attrs); i++) {
+		if ((rc = device_create_file(&adapter->dev, &adapter_attrs[i])))
+			goto err;
+	}
+	return 0;
+err:
+	for (i--; i >= 0; i--)
+		device_remove_file(&adapter->dev, &adapter_attrs[i]);
+	return rc;
+}
+void cxl_sysfs_adapter_remove(struct cxl *adapter)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(adapter_attrs); i++)
+		device_remove_file(&adapter->dev, &adapter_attrs[i]);
+}
+
+int cxl_sysfs_afu_add(struct cxl_afu *afu)
+{
+	int i, rc;
+
+	for (i = 0; i < ARRAY_SIZE(afu_attrs); i++) {
+		if ((rc = device_create_file(&afu->dev, &afu_attrs[i])))
+			goto err;
+	}
+
+	return 0;
+
+err:
+	for (i--; i >= 0; i--)
+		device_remove_file(&afu->dev, &afu_attrs[i]);
+	return rc;
+}
+
+void cxl_sysfs_afu_remove(struct cxl_afu *afu)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(afu_attrs); i++)
+		device_remove_file(&afu->dev, &afu_attrs[i]);
+}
+
+int cxl_sysfs_afu_m_add(struct cxl_afu *afu)
+{
+	int i, rc;
+
+	for (i = 0; i < ARRAY_SIZE(afu_master_attrs); i++) {
+		if ((rc = device_create_file(afu->chardev_m, &afu_master_attrs[i])))
+			goto err;
+	}
+
+	return 0;
+
+err:
+	for (i--; i >= 0; i--)
+		device_remove_file(afu->chardev_m, &afu_master_attrs[i]);
+	return rc;
+}
+
+void cxl_sysfs_afu_m_remove(struct cxl_afu *afu)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(afu_master_attrs); i++)
+		device_remove_file(afu->chardev_m, &afu_master_attrs[i]);
+}