1 files changed, 440 insertions, 0 deletions
diff --git a/drivers/video/tegra/host/nvhost_intr.c b/drivers/video/tegra/host/nvhost_intr.c
new file mode 100644
index 000000000000..1a1a9b3fa4c3
--- /dev/null
+++ b/drivers/video/tegra/host/nvhost_intr.c
@@ -0,0 +1,440 @@
+/*
+ * drivers/video/tegra/host/nvhost_intr.c
+ *
+ * Tegra Graphics Host Interrupt Management
+ *
+ * Copyright (c) 2010-2011, NVIDIA Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#include "nvhost_intr.h"
+#include "dev.h"
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/irq.h>
+#include <trace/events/nvhost.h>
+
+
+
+
+
+/*** Wait list management ***/
+
+struct nvhost_waitlist {
+	struct list_head list;
+	struct kref refcount;
+	u32 thresh;
+	enum nvhost_intr_action action;
+	atomic_t state;
+	void *data;
+	int count;
+};
+
+enum waitlist_state {
+	WLS_PENDING,
+	WLS_REMOVED,
+	WLS_CANCELLED,
+	WLS_HANDLED
+};
+
+static void waiter_release(struct kref *kref)
+{
+	kfree(container_of(kref, struct nvhost_waitlist, refcount));
+}
+
+/**
+ * add a waiter to a waiter queue, sorted by threshold
+ * returns true if it was added at the head of the queue
+ */
+static bool add_waiter_to_queue(struct nvhost_waitlist *waiter,
+				struct list_head *queue)
+{
+	struct nvhost_waitlist *pos;
+	u32 thresh = waiter->thresh;
+
+	list_for_each_entry_reverse(pos, queue, list)
+		if ((s32)(pos->thresh - thresh) <= 0) {
+			list_add(&waiter->list, &pos->list);
+			return false;
+		}
+
+	list_add(&waiter->list, queue);
+	return true;
+}
+
+/**
+ * run through a waiter queue for a single sync point ID
+ * and gather all completed waiters into lists by actions
+ */
+static void remove_completed_waiters(struct list_head *head, u32 sync,
+			struct list_head completed[NVHOST_INTR_ACTION_COUNT])
+{
+	struct list_head *dest;
+	struct nvhost_waitlist *waiter, *next, *prev;
+
+	list_for_each_entry_safe(waiter, next, head, list) {
+		if ((s32)(waiter->thresh - sync) > 0)
+			break;
+
+		dest = completed + waiter->action;
+
+		/* consolidate submit cleanups */
+		if (waiter->action == NVHOST_INTR_ACTION_SUBMIT_COMPLETE
+			&& !list_empty(dest)) {
+			prev = list_entry(dest->prev,
+					struct nvhost_waitlist, list);
+			if (prev->data == waiter->data) {
+				prev->count++;
+				dest = NULL;
+			}
+		}
+
+		/* PENDING->REMOVED or CANCELLED->HANDLED */
+		if (atomic_inc_return(&waiter->state) == WLS_HANDLED || !dest) {
+			list_del(&waiter->list);
+			kref_put(&waiter->refcount, waiter_release);
+		} else {
+			list_move_tail(&waiter->list, dest);
+		}
+	}
+}
+
+void reset_threshold_interrupt(struct nvhost_intr *intr,
+			       struct list_head *head,
+			       unsigned int id)
+{
+	u32 thresh = list_first_entry(head,
+				struct nvhost_waitlist, list)->thresh;
+	BUG_ON(!(intr_op(intr).set_syncpt_threshold &&
+		 intr_op(intr).enable_syncpt_intr));
+
+	intr_op(intr).set_syncpt_threshold(intr, id, thresh);
+	intr_op(intr).enable_syncpt_intr(intr, id);
+}
+
+
+static void action_submit_complete(struct nvhost_waitlist *waiter)
+{
+	struct nvhost_channel *channel = waiter->data;
+	int nr_completed = waiter->count;
+
+	/*  Add nr_completed to trace */
+	trace_nvhost_channel_submit_complete(channel->desc->name,
+			nr_completed);
+
+	nvhost_cdma_update(&channel->cdma);
+	nvhost_module_idle_mult(&channel->mod, nr_completed);
+}
+
+static void action_ctxsave(struct nvhost_waitlist *waiter)
+{
+	struct nvhost_hwctx *hwctx = waiter->data;
+	struct nvhost_channel *channel = hwctx->channel;
+
+	if (channel->ctxhandler.save_service)
+		channel->ctxhandler.save_service(hwctx);
+	channel->ctxhandler.put(hwctx);
+}
+
+static void action_ctxrestore(struct nvhost_waitlist *waiter)
+{
+	struct nvhost_hwctx *hwctx = waiter->data;
+	struct nvhost_channel *channel = hwctx->channel;
+
+	channel->ctxhandler.put(hwctx);
+}
+
+static void action_wakeup(struct nvhost_waitlist *waiter)
+{
+	wait_queue_head_t *wq = waiter->data;
+
+	wake_up(wq);
+}
+
+static void action_wakeup_interruptible(struct nvhost_waitlist *waiter)
+{
+	wait_queue_head_t *wq = waiter->data;
+
+	wake_up_interruptible(wq);
+}
+
+typedef void (*action_handler)(struct nvhost_waitlist *waiter);
+
+static action_handler action_handlers[NVHOST_INTR_ACTION_COUNT] = {
+	action_submit_complete,
+	action_ctxsave,
+	action_ctxrestore,
+	action_wakeup,
+	action_wakeup_interruptible,
+};
+
+static void run_handlers(struct list_head completed[NVHOST_INTR_ACTION_COUNT])
+{
+	struct list_head *head = completed;
+	int i;
+
+	for (i = 0; i < NVHOST_INTR_ACTION_COUNT; ++i, ++head) {
+		action_handler handler = action_handlers[i];
+		struct nvhost_waitlist *waiter, *next;
+
+		list_for_each_entry_safe(waiter, next, head, list) {
+			list_del(&waiter->list);
+			handler(waiter);
+			WARN_ON(atomic_xchg(&waiter->state, WLS_HANDLED) != WLS_REMOVED);
+			kref_put(&waiter->refcount, waiter_release);
+		}
+	}
+}
+
+/**
+ * Remove & handle all waiters that have completed for the given syncpt
+ */
+static int process_wait_list(struct nvhost_intr *intr,
+			     struct nvhost_intr_syncpt *syncpt,
+			     u32 threshold)
+{
+	struct list_head completed[NVHOST_INTR_ACTION_COUNT];
+	unsigned int i;
+	int empty;
+
+	for (i = 0; i < NVHOST_INTR_ACTION_COUNT; ++i)
+		INIT_LIST_HEAD(completed + i);
+
+	spin_lock(&syncpt->lock);
+
+	remove_completed_waiters(&syncpt->wait_head, threshold, completed);
+
+	empty = list_empty(&syncpt->wait_head);
+	if (!empty)
+		reset_threshold_interrupt(intr, &syncpt->wait_head,
+					  syncpt->id);
+
+	spin_unlock(&syncpt->lock);
+
+	run_handlers(completed);
+
+	return empty;
+}
+
+/*** host syncpt interrupt service functions ***/
+/**
+ * Sync point threshold interrupt service thread function
+ * Handles sync point threshold triggers, in thread context
+ */
+irqreturn_t nvhost_syncpt_thresh_fn(int irq, void *dev_id)
+{
+	struct nvhost_intr_syncpt *syncpt = dev_id;
+	unsigned int id = syncpt->id;
+	struct nvhost_intr *intr = intr_syncpt_to_intr(syncpt);
+	struct nvhost_master *dev = intr_to_dev(intr);
+
+	(void)process_wait_list(intr, syncpt,
+				nvhost_syncpt_update_min(&dev->syncpt, id));
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * free a syncpt's irq. syncpt interrupt should be disabled first.
+ */
+static void free_syncpt_irq(struct nvhost_intr_syncpt *syncpt)
+{
+	if (syncpt->irq_requested) {
+		free_irq(syncpt->irq, syncpt);
+		syncpt->irq_requested = 0;
+	}
+}
+
+
+/*** host general interrupt service functions ***/
+
+
+/*** Main API ***/
+
+int nvhost_intr_add_action(struct nvhost_intr *intr, u32 id, u32 thresh,
+			enum nvhost_intr_action action, void *data,
+			void *_waiter,
+			void **ref)
+{
+	struct nvhost_waitlist *waiter = _waiter;
+	struct nvhost_intr_syncpt *syncpt;
+	int queue_was_empty;
+	int err;
+
+	BUG_ON(waiter == NULL);
+
+	BUG_ON(!(intr_op(intr).set_syncpt_threshold &&
+		 intr_op(intr).enable_syncpt_intr));
+
+	/* initialize a new waiter */
+	INIT_LIST_HEAD(&waiter->list);
+	kref_init(&waiter->refcount);
+	if (ref)
+		kref_get(&waiter->refcount);
+	waiter->thresh = thresh;
+	waiter->action = action;
+	atomic_set(&waiter->state, WLS_PENDING);
+	waiter->data = data;
+	waiter->count = 1;
+
+	BUG_ON(id >= intr_to_dev(intr)->syncpt.nb_pts);
+	syncpt = intr->syncpt + id;
+
+	spin_lock(&syncpt->lock);
+
+	/* lazily request irq for this sync point */
+	if (!syncpt->irq_requested) {
+		spin_unlock(&syncpt->lock);
+
+		mutex_lock(&intr->mutex);
+		BUG_ON(!(intr_op(intr).request_syncpt_irq));
+		err = intr_op(intr).request_syncpt_irq(syncpt);
+		mutex_unlock(&intr->mutex);
+
+		if (err) {
+			kfree(waiter);
+			return err;
+		}
+
+		spin_lock(&syncpt->lock);
+	}
+
+	queue_was_empty = list_empty(&syncpt->wait_head);
+
+	if (add_waiter_to_queue(waiter, &syncpt->wait_head)) {
+		/* added at head of list - new threshold value */
+		intr_op(intr).set_syncpt_threshold(intr, id, thresh);
+
+		/* added as first waiter - enable interrupt */
+		if (queue_was_empty)
+			intr_op(intr).enable_syncpt_intr(intr, id);
+	}
+
+	spin_unlock(&syncpt->lock);
+
+	if (ref)
+		*ref = waiter;
+	return 0;
+}
+
+void *nvhost_intr_alloc_waiter()
+{
+	return kzalloc(sizeof(struct nvhost_waitlist),
+			GFP_KERNEL|__GFP_REPEAT);
+}
+
+void nvhost_intr_put_ref(struct nvhost_intr *intr, void *ref)
+{
+	struct nvhost_waitlist *waiter = ref;
+
+	while (atomic_cmpxchg(&waiter->state,
+				WLS_PENDING, WLS_CANCELLED) == WLS_REMOVED)
+		schedule();
+
+	kref_put(&waiter->refcount, waiter_release);
+}
+
+
+/*** Init & shutdown ***/
+
+int nvhost_intr_init(struct nvhost_intr *intr, u32 irq_gen, u32 irq_sync)
+{
+	unsigned int id;
+	struct nvhost_intr_syncpt *syncpt;
+	struct nvhost_master *host =
+		container_of(intr, struct nvhost_master, intr);
+	u32 nb_pts = host->syncpt.nb_pts;
+
+	mutex_init(&intr->mutex);
+	intr->host_general_irq = irq_gen;
+	intr->host_general_irq_requested = false;
+
+	for (id = 0, syncpt = intr->syncpt;
+	     id < nb_pts;
+	     ++id, ++syncpt) {
+		syncpt->intr = &host->intr;
+		syncpt->id = id;
+		syncpt->irq = irq_sync + id;
+		syncpt->irq_requested = 0;
+		spin_lock_init(&syncpt->lock);
+		INIT_LIST_HEAD(&syncpt->wait_head);
+		snprintf(syncpt->thresh_irq_name,
+			sizeof(syncpt->thresh_irq_name),
+			"host_sp_%02d", id);
+	}
+
+	return 0;
+}
+
+void nvhost_intr_deinit(struct nvhost_intr *intr)
+{
+	nvhost_intr_stop(intr);
+}
+
+void nvhost_intr_start(struct nvhost_intr *intr, u32 hz)
+{
+	BUG_ON(!(intr_op(intr).init_host_sync &&
+		 intr_op(intr).set_host_clocks_per_usec &&
+		 intr_op(intr).request_host_general_irq));
+
+	mutex_lock(&intr->mutex);
+
+	intr_op(intr).init_host_sync(intr);
+	intr_op(intr).set_host_clocks_per_usec(intr,
+					       (hz + 1000000 - 1)/1000000);
+
+	intr_op(intr).request_host_general_irq(intr);
+
+	mutex_unlock(&intr->mutex);
+}
+
+void nvhost_intr_stop(struct nvhost_intr *intr)
+{
+	unsigned int id;
+	struct nvhost_intr_syncpt *syncpt;
+	u32 nb_pts = intr_to_dev(intr)->syncpt.nb_pts;
+
+	BUG_ON(!(intr_op(intr).disable_all_syncpt_intrs &&
+		 intr_op(intr).free_host_general_irq));
+
+	mutex_lock(&intr->mutex);
+
+	intr_op(intr).disable_all_syncpt_intrs(intr);
+
+	for (id = 0, syncpt = intr->syncpt;
+	     id < nb_pts;
+	     ++id, ++syncpt) {
+		struct nvhost_waitlist *waiter, *next;
+		list_for_each_entry_safe(waiter, next, &syncpt->wait_head, list) {
+			if (atomic_cmpxchg(&waiter->state, WLS_CANCELLED, WLS_HANDLED)
+				== WLS_CANCELLED) {
+				list_del(&waiter->list);
+				kref_put(&waiter->refcount, waiter_release);
+			}
+		}
+
+		if (!list_empty(&syncpt->wait_head)) {  /* output diagnostics */
+			printk(KERN_DEBUG "%s id=%d\n", __func__, id);
+			BUG_ON(1);
+		}
+
+		free_syncpt_irq(syncpt);
+	}
+
+	intr_op(intr).free_host_general_irq(intr);
+
+	mutex_unlock(&intr->mutex);
+}