Fixed MTP to work with TWRP

drivers/misc/mic/host/mic_intr.c

@@ -0,0 +1,653 @@
+/*
+ * Intel MIC Platform Software Stack (MPSS)
+ *
+ * Copyright(c) 2013 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ *
+ * Intel MIC Host driver.
+ *
+ */
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+
+#include "../common/mic_dev.h"
+#include "mic_device.h"
+
+static irqreturn_t mic_thread_fn(int irq, void *dev)
+{
+	struct mic_device *mdev = dev;
+	struct mic_intr_info *intr_info = mdev->intr_info;
+	struct mic_irq_info *irq_info = &mdev->irq_info;
+	struct mic_intr_cb *intr_cb;
+	struct pci_dev *pdev = container_of(mdev->sdev->parent,
+					    struct pci_dev, dev);
+	int i;
+
+	spin_lock(&irq_info->mic_thread_lock);
+	for (i = intr_info->intr_start_idx[MIC_INTR_DB];
+			i < intr_info->intr_len[MIC_INTR_DB]; i++)
+		if (test_and_clear_bit(i, &irq_info->mask)) {
+			list_for_each_entry(intr_cb, &irq_info->cb_list[i],
+					    list)
+				if (intr_cb->thread_fn)
+					intr_cb->thread_fn(pdev->irq,
+							 intr_cb->data);
+		}
+	spin_unlock(&irq_info->mic_thread_lock);
+	return IRQ_HANDLED;
+}
+/**
+ * mic_interrupt - Generic interrupt handler for
+ * MSI and INTx based interrupts.
+ */
+static irqreturn_t mic_interrupt(int irq, void *dev)
+{
+	struct mic_device *mdev = dev;
+	struct mic_intr_info *intr_info = mdev->intr_info;
+	struct mic_irq_info *irq_info = &mdev->irq_info;
+	struct mic_intr_cb *intr_cb;
+	struct pci_dev *pdev = container_of(mdev->sdev->parent,
+					    struct pci_dev, dev);
+	u32 mask;
+	int i;
+
+	mask = mdev->ops->ack_interrupt(mdev);
+	if (!mask)
+		return IRQ_NONE;
+
+	spin_lock(&irq_info->mic_intr_lock);
+	for (i = intr_info->intr_start_idx[MIC_INTR_DB];
+			i < intr_info->intr_len[MIC_INTR_DB]; i++)
+		if (mask & BIT(i)) {
+			list_for_each_entry(intr_cb, &irq_info->cb_list[i],
+					    list)
+				if (intr_cb->handler)
+					intr_cb->handler(pdev->irq,
+							 intr_cb->data);
+			set_bit(i, &irq_info->mask);
+		}
+	spin_unlock(&irq_info->mic_intr_lock);
+	return IRQ_WAKE_THREAD;
+}
+
+/* Return the interrupt offset from the index. Index is 0 based. */
+static u16 mic_map_src_to_offset(struct mic_device *mdev,
+		int intr_src, enum mic_intr_type type)
+{
+	if (type >= MIC_NUM_INTR_TYPES)
+		return MIC_NUM_OFFSETS;
+	if (intr_src >= mdev->intr_info->intr_len[type])
+		return MIC_NUM_OFFSETS;
+
+	return mdev->intr_info->intr_start_idx[type] + intr_src;
+}
+
+/* Return next available msix_entry. */
+static struct msix_entry *mic_get_available_vector(struct mic_device *mdev)
+{
+	int i;
+	struct mic_irq_info *info = &mdev->irq_info;
+
+	for (i = 0; i < info->num_vectors; i++)
+		if (!info->mic_msi_map[i])
+			return &info->msix_entries[i];
+	return NULL;
+}
+
+/**
+ * mic_register_intr_callback - Register a callback handler for the
+ * given source id.
+ *
+ * @mdev: pointer to the mic_device instance
+ * @idx: The source id to be registered.
+ * @handler: The function to be called when the source id receives
+ * the interrupt.
+ * @thread_fn: thread fn. corresponding to the handler
+ * @data: Private data of the requester.
+ * Return the callback structure that was registered or an
+ * appropriate error on failure.
+ */
+static struct mic_intr_cb *mic_register_intr_callback(struct mic_device *mdev,
+			u8 idx, irq_handler_t handler, irq_handler_t thread_fn,
+			void *data)
+{
+	struct mic_intr_cb *intr_cb;
+	unsigned long flags;
+	int rc;
+	intr_cb = kmalloc(sizeof(*intr_cb), GFP_KERNEL);
+
+	if (!intr_cb)
+		return ERR_PTR(-ENOMEM);
+
+	intr_cb->handler = handler;
+	intr_cb->thread_fn = thread_fn;
+	intr_cb->data = data;
+	intr_cb->cb_id = ida_simple_get(&mdev->irq_info.cb_ida,
+		0, 0, GFP_KERNEL);
+	if (intr_cb->cb_id < 0) {
+		rc = intr_cb->cb_id;
+		goto ida_fail;
+	}
+
+	spin_lock(&mdev->irq_info.mic_thread_lock);
+	spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
+	list_add_tail(&intr_cb->list, &mdev->irq_info.cb_list[idx]);
+	spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
+	spin_unlock(&mdev->irq_info.mic_thread_lock);
+
+	return intr_cb;
+ida_fail:
+	kfree(intr_cb);
+	return ERR_PTR(rc);
+}
+
+/**
+ * mic_unregister_intr_callback - Unregister the callback handler
+ * identified by its callback id.
+ *
+ * @mdev: pointer to the mic_device instance
+ * @idx: The callback structure id to be unregistered.
+ * Return the source id that was unregistered or MIC_NUM_OFFSETS if no
+ * such callback handler was found.
+ */
+static u8 mic_unregister_intr_callback(struct mic_device *mdev, u32 idx)
+{
+	struct list_head *pos, *tmp;
+	struct mic_intr_cb *intr_cb;
+	unsigned long flags;
+	int i;
+
+	spin_lock(&mdev->irq_info.mic_thread_lock);
+	spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
+	for (i = 0;  i < MIC_NUM_OFFSETS; i++) {
+		list_for_each_safe(pos, tmp, &mdev->irq_info.cb_list[i]) {
+			intr_cb = list_entry(pos, struct mic_intr_cb, list);
+			if (intr_cb->cb_id == idx) {
+				list_del(pos);
+				ida_simple_remove(&mdev->irq_info.cb_ida,
+						  intr_cb->cb_id);
+				kfree(intr_cb);
+				spin_unlock_irqrestore(
+					&mdev->irq_info.mic_intr_lock, flags);
+				spin_unlock(&mdev->irq_info.mic_thread_lock);
+				return i;
+			}
+		}
+	}
+	spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
+	spin_unlock(&mdev->irq_info.mic_thread_lock);
+	return MIC_NUM_OFFSETS;
+}
+
+/**
+ * mic_setup_msix - Initializes MSIx interrupts.
+ *
+ * @mdev: pointer to mic_device instance
+ *
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+static int mic_setup_msix(struct mic_device *mdev, struct pci_dev *pdev)
+{
+	int rc, i;
+	int entry_size = sizeof(*mdev->irq_info.msix_entries);
+
+	mdev->irq_info.msix_entries = kmalloc_array(MIC_MIN_MSIX,
+						    entry_size, GFP_KERNEL);
+	if (!mdev->irq_info.msix_entries) {
+		rc = -ENOMEM;
+		goto err_nomem1;
+	}
+
+	for (i = 0; i < MIC_MIN_MSIX; i++)
+		mdev->irq_info.msix_entries[i].entry = i;
+
+	rc = pci_enable_msix_exact(pdev, mdev->irq_info.msix_entries,
+		MIC_MIN_MSIX);
+	if (rc) {
+		dev_dbg(&pdev->dev, "Error enabling MSIx. rc = %d\n", rc);
+		goto err_enable_msix;
+	}
+
+	mdev->irq_info.num_vectors = MIC_MIN_MSIX;
+	mdev->irq_info.mic_msi_map = kzalloc((sizeof(u32) *
+		mdev->irq_info.num_vectors), GFP_KERNEL);
+
+	if (!mdev->irq_info.mic_msi_map) {
+		rc = -ENOMEM;
+		goto err_nomem2;
+	}
+
+	dev_dbg(mdev->sdev->parent,
+		"%d MSIx irqs setup\n", mdev->irq_info.num_vectors);
+	return 0;
+err_nomem2:
+	pci_disable_msix(pdev);
+err_enable_msix:
+	kfree(mdev->irq_info.msix_entries);
+err_nomem1:
+	mdev->irq_info.num_vectors = 0;
+	return rc;
+}
+
+/**
+ * mic_setup_callbacks - Initialize data structures needed
+ * to handle callbacks.
+ *
+ * @mdev: pointer to mic_device instance
+ */
+static int mic_setup_callbacks(struct mic_device *mdev)
+{
+	int i;
+
+	mdev->irq_info.cb_list = kmalloc_array(MIC_NUM_OFFSETS,
+					       sizeof(*mdev->irq_info.cb_list),
+					       GFP_KERNEL);
+	if (!mdev->irq_info.cb_list)
+		return -ENOMEM;
+
+	for (i = 0; i < MIC_NUM_OFFSETS; i++)
+		INIT_LIST_HEAD(&mdev->irq_info.cb_list[i]);
+	ida_init(&mdev->irq_info.cb_ida);
+	spin_lock_init(&mdev->irq_info.mic_intr_lock);
+	spin_lock_init(&mdev->irq_info.mic_thread_lock);
+	return 0;
+}
+
+/**
+ * mic_release_callbacks - Uninitialize data structures needed
+ * to handle callbacks.
+ *
+ * @mdev: pointer to mic_device instance
+ */
+static void mic_release_callbacks(struct mic_device *mdev)
+{
+	unsigned long flags;
+	struct list_head *pos, *tmp;
+	struct mic_intr_cb *intr_cb;
+	int i;
+
+	spin_lock(&mdev->irq_info.mic_thread_lock);
+	spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
+	for (i = 0; i < MIC_NUM_OFFSETS; i++) {
+
+		if (list_empty(&mdev->irq_info.cb_list[i]))
+			break;
+
+		list_for_each_safe(pos, tmp, &mdev->irq_info.cb_list[i]) {
+			intr_cb = list_entry(pos, struct mic_intr_cb, list);
+			list_del(pos);
+			ida_simple_remove(&mdev->irq_info.cb_ida,
+					  intr_cb->cb_id);
+			kfree(intr_cb);
+		}
+	}
+	spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
+	spin_unlock(&mdev->irq_info.mic_thread_lock);
+	ida_destroy(&mdev->irq_info.cb_ida);
+	kfree(mdev->irq_info.cb_list);
+}
+
+/**
+ * mic_setup_msi - Initializes MSI interrupts.
+ *
+ * @mdev: pointer to mic_device instance
+ * @pdev: PCI device structure
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+static int mic_setup_msi(struct mic_device *mdev, struct pci_dev *pdev)
+{
+	int rc;
+
+	rc = pci_enable_msi(pdev);
+	if (rc) {
+		dev_dbg(&pdev->dev, "Error enabling MSI. rc = %d\n", rc);
+		return rc;
+	}
+
+	mdev->irq_info.num_vectors = 1;
+	mdev->irq_info.mic_msi_map = kzalloc((sizeof(u32) *
+		mdev->irq_info.num_vectors), GFP_KERNEL);
+
+	if (!mdev->irq_info.mic_msi_map) {
+		rc = -ENOMEM;
+		goto err_nomem1;
+	}
+
+	rc = mic_setup_callbacks(mdev);
+	if (rc) {
+		dev_err(&pdev->dev, "Error setting up callbacks\n");
+		goto err_nomem2;
+	}
+
+	rc = request_threaded_irq(pdev->irq, mic_interrupt, mic_thread_fn,
+				  0, "mic-msi", mdev);
+	if (rc) {
+		dev_err(&pdev->dev, "Error allocating MSI interrupt\n");
+		goto err_irq_req_fail;
+	}
+
+	dev_dbg(&pdev->dev, "%d MSI irqs setup\n", mdev->irq_info.num_vectors);
+	return 0;
+err_irq_req_fail:
+	mic_release_callbacks(mdev);
+err_nomem2:
+	kfree(mdev->irq_info.mic_msi_map);
+err_nomem1:
+	pci_disable_msi(pdev);
+	mdev->irq_info.num_vectors = 0;
+	return rc;
+}
+
+/**
+ * mic_setup_intx - Initializes legacy interrupts.
+ *
+ * @mdev: pointer to mic_device instance
+ * @pdev: PCI device structure
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+static int mic_setup_intx(struct mic_device *mdev, struct pci_dev *pdev)
+{
+	int rc;
+
+	pci_msi_off(pdev);
+
+	/* Enable intx */
+	pci_intx(pdev, 1);
+	rc = mic_setup_callbacks(mdev);
+	if (rc) {
+		dev_err(&pdev->dev, "Error setting up callbacks\n");
+		goto err_nomem;
+	}
+
+	rc = request_threaded_irq(pdev->irq, mic_interrupt, mic_thread_fn,
+				  IRQF_SHARED, "mic-intx", mdev);
+	if (rc)
+		goto err;
+
+	dev_dbg(&pdev->dev, "intx irq setup\n");
+	return 0;
+err:
+	mic_release_callbacks(mdev);
+err_nomem:
+	return rc;
+}
+
+/**
+ * mic_next_db - Retrieve the next doorbell interrupt source id.
+ * The id is picked sequentially from the available pool of
+ * doorlbell ids.
+ *
+ * @mdev: pointer to the mic_device instance.
+ *
+ * Returns the next doorbell interrupt source.
+ */
+int mic_next_db(struct mic_device *mdev)
+{
+	int next_db;
+
+	next_db = mdev->irq_info.next_avail_src %
+		mdev->intr_info->intr_len[MIC_INTR_DB];
+	mdev->irq_info.next_avail_src++;
+	return next_db;
+}
+
+#define COOKIE_ID_SHIFT 16
+#define GET_ENTRY(cookie) ((cookie) & 0xFFFF)
+#define GET_OFFSET(cookie) ((cookie) >> COOKIE_ID_SHIFT)
+#define MK_COOKIE(x, y) ((x) | (y) << COOKIE_ID_SHIFT)
+
+/**
+ * mic_request_threaded_irq - request an irq. mic_mutex needs
+ * to be held before calling this function.
+ *
+ * @mdev: pointer to mic_device instance
+ * @handler: The callback function that handles the interrupt.
+ * The function needs to call ack_interrupts
+ * (mdev->ops->ack_interrupt(mdev)) when handling the interrupts.
+ * @thread_fn: thread fn required by request_threaded_irq.
+ * @name: The ASCII name of the callee requesting the irq.
+ * @data: private data that is returned back when calling the
+ * function handler.
+ * @intr_src: The source id of the requester. Its the doorbell id
+ * for Doorbell interrupts and DMA channel id for DMA interrupts.
+ * @type: The type of interrupt. Values defined in mic_intr_type
+ *
+ * returns: The cookie that is transparent to the caller. Passed
+ * back when calling mic_free_irq. An appropriate error code
+ * is returned on failure. Caller needs to use IS_ERR(return_val)
+ * to check for failure and PTR_ERR(return_val) to obtained the
+ * error code.
+ *
+ */
+struct mic_irq *
+mic_request_threaded_irq(struct mic_device *mdev,
+			 irq_handler_t handler, irq_handler_t thread_fn,
+			 const char *name, void *data, int intr_src,
+			 enum mic_intr_type type)
+{
+	u16 offset;
+	int rc = 0;
+	struct msix_entry *msix = NULL;
+	unsigned long cookie = 0;
+	u16 entry;
+	struct mic_intr_cb *intr_cb;
+	struct pci_dev *pdev = container_of(mdev->sdev->parent,
+		struct pci_dev, dev);
+
+	offset = mic_map_src_to_offset(mdev, intr_src, type);
+	if (offset >= MIC_NUM_OFFSETS) {
+		dev_err(mdev->sdev->parent,
+			"Error mapping index %d to a valid source id.\n",
+			intr_src);
+		rc = -EINVAL;
+		goto err;
+	}
+
+	if (mdev->irq_info.num_vectors > 1) {
+		msix = mic_get_available_vector(mdev);
+		if (!msix) {
+			dev_err(mdev->sdev->parent,
+				"No MSIx vectors available for use.\n");
+			rc = -ENOSPC;
+			goto err;
+		}
+
+		rc = request_threaded_irq(msix->vector, handler, thread_fn,
+					  0, name, data);
+		if (rc) {
+			dev_dbg(mdev->sdev->parent,
+				"request irq failed rc = %d\n", rc);
+			goto err;
+		}
+		entry = msix->entry;
+		mdev->irq_info.mic_msi_map[entry] |= BIT(offset);
+		mdev->intr_ops->program_msi_to_src_map(mdev,
+				entry, offset, true);
+		cookie = MK_COOKIE(entry, offset);
+		dev_dbg(mdev->sdev->parent, "irq: %d assigned for src: %d\n",
+			msix->vector, intr_src);
+	} else {
+		intr_cb = mic_register_intr_callback(mdev, offset, handler,
+						     thread_fn, data);
+		if (IS_ERR(intr_cb)) {
+			dev_err(mdev->sdev->parent,
+				"No available callback entries for use\n");
+			rc = PTR_ERR(intr_cb);
+			goto err;
+		}
+
+		entry = 0;
+		if (pci_dev_msi_enabled(pdev)) {
+			mdev->irq_info.mic_msi_map[entry] |= (1 << offset);
+			mdev->intr_ops->program_msi_to_src_map(mdev,
+				entry, offset, true);
+		}
+		cookie = MK_COOKIE(entry, intr_cb->cb_id);
+		dev_dbg(mdev->sdev->parent, "callback %d registered for src: %d\n",
+			intr_cb->cb_id, intr_src);
+	}
+	return (struct mic_irq *)cookie;
+err:
+	return ERR_PTR(rc);
+}
+
+/**
+ * mic_free_irq - free irq. mic_mutex
+ *  needs to be held before calling this function.
+ *
+ * @mdev: pointer to mic_device instance
+ * @cookie: cookie obtained during a successful call to mic_request_threaded_irq
+ * @data: private data specified by the calling function during the
+ * mic_request_threaded_irq
+ *
+ * returns: none.
+ */
+void mic_free_irq(struct mic_device *mdev,
+	struct mic_irq *cookie, void *data)
+{
+	u32 offset;
+	u32 entry;
+	u8 src_id;
+	unsigned int irq;
+	struct pci_dev *pdev = container_of(mdev->sdev->parent,
+		struct pci_dev, dev);
+
+	entry = GET_ENTRY((unsigned long)cookie);
+	offset = GET_OFFSET((unsigned long)cookie);
+	if (mdev->irq_info.num_vectors > 1) {
+		if (entry >= mdev->irq_info.num_vectors) {
+			dev_warn(mdev->sdev->parent,
+				 "entry %d should be < num_irq %d\n",
+				entry, mdev->irq_info.num_vectors);
+			return;
+		}
+		irq = mdev->irq_info.msix_entries[entry].vector;
+		free_irq(irq, data);
+		mdev->irq_info.mic_msi_map[entry] &= ~(BIT(offset));
+		mdev->intr_ops->program_msi_to_src_map(mdev,
+			entry, offset, false);
+
+		dev_dbg(mdev->sdev->parent, "irq: %d freed\n", irq);
+	} else {
+		irq = pdev->irq;
+		src_id = mic_unregister_intr_callback(mdev, offset);
+		if (src_id >= MIC_NUM_OFFSETS) {
+			dev_warn(mdev->sdev->parent, "Error unregistering callback\n");
+			return;
+		}
+		if (pci_dev_msi_enabled(pdev)) {
+			mdev->irq_info.mic_msi_map[entry] &= ~(BIT(src_id));
+			mdev->intr_ops->program_msi_to_src_map(mdev,
+				entry, src_id, false);
+		}
+		dev_dbg(mdev->sdev->parent, "callback %d unregistered for src: %d\n",
+			offset, src_id);
+	}
+}
+
+/**
+ * mic_setup_interrupts - Initializes interrupts.
+ *
+ * @mdev: pointer to mic_device instance
+ * @pdev: PCI device structure
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int mic_setup_interrupts(struct mic_device *mdev, struct pci_dev *pdev)
+{
+	int rc;
+
+	rc = mic_setup_msix(mdev, pdev);
+	if (!rc)
+		goto done;
+
+	rc = mic_setup_msi(mdev, pdev);
+	if (!rc)
+		goto done;
+
+	rc = mic_setup_intx(mdev, pdev);
+	if (rc) {
+		dev_err(mdev->sdev->parent, "no usable interrupts\n");
+		return rc;
+	}
+done:
+	mdev->intr_ops->enable_interrupts(mdev);
+	return 0;
+}
+
+/**
+ * mic_free_interrupts - Frees interrupts setup by mic_setup_interrupts
+ *
+ * @mdev: pointer to mic_device instance
+ * @pdev: PCI device structure
+ *
+ * returns none.
+ */
+void mic_free_interrupts(struct mic_device *mdev, struct pci_dev *pdev)
+{
+	int i;
+
+	mdev->intr_ops->disable_interrupts(mdev);
+	if (mdev->irq_info.num_vectors > 1) {
+		for (i = 0; i < mdev->irq_info.num_vectors; i++) {
+			if (mdev->irq_info.mic_msi_map[i])
+				dev_warn(&pdev->dev, "irq %d may still be in use.\n",
+					 mdev->irq_info.msix_entries[i].vector);
+		}
+		kfree(mdev->irq_info.mic_msi_map);
+		kfree(mdev->irq_info.msix_entries);
+		pci_disable_msix(pdev);
+	} else {
+		if (pci_dev_msi_enabled(pdev)) {
+			free_irq(pdev->irq, mdev);
+			kfree(mdev->irq_info.mic_msi_map);
+			pci_disable_msi(pdev);
+		} else {
+			free_irq(pdev->irq, mdev);
+		}
+		mic_release_callbacks(mdev);
+	}
+}
+
+/**
+ * mic_intr_restore - Restore MIC interrupt registers.
+ *
+ * @mdev: pointer to mic_device instance.
+ *
+ * Restore the interrupt registers to values previously
+ * stored in the SW data structures. mic_mutex needs to
+ * be held before calling this function.
+ *
+ * returns None.
+ */
+void mic_intr_restore(struct mic_device *mdev)
+{
+	int entry, offset;
+	struct pci_dev *pdev = container_of(mdev->sdev->parent,
+		struct pci_dev, dev);
+
+	if (!pci_dev_msi_enabled(pdev))
+		return;
+
+	for (entry = 0; entry < mdev->irq_info.num_vectors; entry++) {
+		for (offset = 0; offset < MIC_NUM_OFFSETS; offset++) {
+			if (mdev->irq_info.mic_msi_map[entry] & BIT(offset))
+				mdev->intr_ops->program_msi_to_src_map(mdev,
+					entry, offset, true);
+		}
+	}
+}