[linux-block.git] / drivers / gpu / host1x / intr.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Tegra host1x Interrupt Management
 *
 * Copyright (c) 2010-2013, NVIDIA Corporation.
 */

#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/irq.h>

#include <trace/events/host1x.h>
#include "channel.h"
#include "dev.h"
#include "intr.h"

/* Wait list management */

enum waitlist_state {
	WLS_PENDING,
	WLS_REMOVED,
	WLS_CANCELLED,
	WLS_HANDLED
};

static void waiter_release(struct kref *kref)
{
	kfree(container_of(kref, struct host1x_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 host1x_waitlist *waiter,
				struct list_head *queue)
{
	struct host1x_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[HOST1X_INTR_ACTION_COUNT])
{
	struct list_head *dest;
	struct host1x_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 == HOST1X_INTR_ACTION_SUBMIT_COMPLETE &&
		    !list_empty(dest)) {
			prev = list_entry(dest->prev,
					  struct host1x_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);
	}
}

static void reset_threshold_interrupt(struct host1x *host,
				      struct list_head *head,
				      unsigned int id)
{
	u32 thresh =
		list_first_entry(head, struct host1x_waitlist, list)->thresh;

	host1x_hw_intr_set_syncpt_threshold(host, id, thresh);
	host1x_hw_intr_enable_syncpt_intr(host, id);
}

static void action_submit_complete(struct host1x_waitlist *waiter)
{
	struct host1x_channel *channel = waiter->data;

	host1x_cdma_update(&channel->cdma);

	/*  Add nr_completed to trace */
	trace_host1x_channel_submit_complete(dev_name(channel->dev),
					     waiter->count, waiter->thresh);

}

static void action_wakeup(struct host1x_waitlist *waiter)
{
	wait_queue_head_t *wq = waiter->data;

	wake_up(wq);
}

static void action_wakeup_interruptible(struct host1x_waitlist *waiter)
{
	wait_queue_head_t *wq = waiter->data;

	wake_up_interruptible(wq);
}

typedef void (*action_handler)(struct host1x_waitlist *waiter);

static const action_handler action_handlers[HOST1X_INTR_ACTION_COUNT] = {
	action_submit_complete,
	action_wakeup,
	action_wakeup_interruptible,
};

static void run_handlers(struct list_head completed[HOST1X_INTR_ACTION_COUNT])
{
	struct list_head *head = completed;
	unsigned int i;

	for (i = 0; i < HOST1X_INTR_ACTION_COUNT; ++i, ++head) {
		action_handler handler = action_handlers[i];
		struct host1x_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 host1x *host,
			     struct host1x_syncpt *syncpt,
			     u32 threshold)
{
	struct list_head completed[HOST1X_INTR_ACTION_COUNT];
	unsigned int i;
	int empty;

	for (i = 0; i < HOST1X_INTR_ACTION_COUNT; ++i)
		INIT_LIST_HEAD(completed + i);

	spin_lock(&syncpt->intr.lock);

	remove_completed_waiters(&syncpt->intr.wait_head, threshold,
				 completed);

	empty = list_empty(&syncpt->intr.wait_head);
	if (empty)
		host1x_hw_intr_disable_syncpt_intr(host, syncpt->id);
	else
		reset_threshold_interrupt(host, &syncpt->intr.wait_head,
					  syncpt->id);

	spin_unlock(&syncpt->intr.lock);

	run_handlers(completed);

	return empty;
}

/*
 * Sync point threshold interrupt service thread function
 * Handles sync point threshold triggers, in thread context
 */

static void syncpt_thresh_work(struct work_struct *work)
{
	struct host1x_syncpt_intr *syncpt_intr =
		container_of(work, struct host1x_syncpt_intr, work);
	struct host1x_syncpt *syncpt =
		container_of(syncpt_intr, struct host1x_syncpt, intr);
	unsigned int id = syncpt->id;
	struct host1x *host = syncpt->host;

	(void)process_wait_list(host, syncpt,
				host1x_syncpt_load(host->syncpt + id));
}

int host1x_intr_add_action(struct host1x *host, struct host1x_syncpt *syncpt,
			   u32 thresh, enum host1x_intr_action action,
			   void *data, struct host1x_waitlist *waiter,
			   void **ref)
{
	int queue_was_empty;

	if (waiter == NULL) {
		pr_warn("%s: NULL waiter\n", __func__);
		return -EINVAL;
	}

	/* 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;

	spin_lock(&syncpt->intr.lock);

	queue_was_empty = list_empty(&syncpt->intr.wait_head);

	if (add_waiter_to_queue(waiter, &syncpt->intr.wait_head)) {
		/* added at head of list - new threshold value */
		host1x_hw_intr_set_syncpt_threshold(host, syncpt->id, thresh);

		/* added as first waiter - enable interrupt */
		if (queue_was_empty)
			host1x_hw_intr_enable_syncpt_intr(host, syncpt->id);
	}

	spin_unlock(&syncpt->intr.lock);

	if (ref)
		*ref = waiter;
	return 0;
}

void host1x_intr_put_ref(struct host1x *host, unsigned int id, void *ref)
{
	struct host1x_waitlist *waiter = ref;
	struct host1x_syncpt *syncpt;

	while (atomic_cmpxchg(&waiter->state, WLS_PENDING, WLS_CANCELLED) ==
	       WLS_REMOVED)
		schedule();

	syncpt = host->syncpt + id;
	(void)process_wait_list(host, syncpt,
				host1x_syncpt_load(host->syncpt + id));

	kref_put(&waiter->refcount, waiter_release);
}

int host1x_intr_init(struct host1x *host, unsigned int irq_sync)
{
	unsigned int id;
	u32 nb_pts = host1x_syncpt_nb_pts(host);

	mutex_init(&host->intr_mutex);
	host->intr_syncpt_irq = irq_sync;

	for (id = 0; id < nb_pts; ++id) {
		struct host1x_syncpt *syncpt = host->syncpt + id;

		spin_lock_init(&syncpt->intr.lock);
		INIT_LIST_HEAD(&syncpt->intr.wait_head);
		snprintf(syncpt->intr.thresh_irq_name,
			 sizeof(syncpt->intr.thresh_irq_name),
			 "host1x_sp_%02u", id);
	}

	host1x_intr_start(host);

	return 0;
}

void host1x_intr_deinit(struct host1x *host)
{
	host1x_intr_stop(host);
}

void host1x_intr_start(struct host1x *host)
{
	u32 hz = clk_get_rate(host->clk);
	int err;

	mutex_lock(&host->intr_mutex);
	err = host1x_hw_intr_init_host_sync(host, DIV_ROUND_UP(hz, 1000000),
					    syncpt_thresh_work);
	if (err) {
		mutex_unlock(&host->intr_mutex);
		return;
	}
	mutex_unlock(&host->intr_mutex);
}

void host1x_intr_stop(struct host1x *host)
{
	unsigned int id;
	struct host1x_syncpt *syncpt = host->syncpt;
	u32 nb_pts = host1x_syncpt_nb_pts(host);

	mutex_lock(&host->intr_mutex);

	host1x_hw_intr_disable_all_syncpt_intrs(host);

	for (id = 0; id < nb_pts; ++id) {
		struct host1x_waitlist *waiter, *next;

		list_for_each_entry_safe(waiter, next,
			&syncpt[id].intr.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[id].intr.wait_head)) {
			/* output diagnostics */
			mutex_unlock(&host->intr_mutex);
			pr_warn("%s cannot stop syncpt intr id=%u\n",
				__func__, id);
			return;
		}
	}

	host1x_hw_intr_free_syncpt_irq(host);

	mutex_unlock(&host->intr_mutex);
}
Commit	Line	Data
9952f691	1	// SPDX-License-Identifier: GPL-2.0-only
7ede0b0b TB	2	/*
	3	* Tegra host1x Interrupt Management
	4	*
	5	* Copyright (c) 2010-2013, NVIDIA Corporation.
7ede0b0b TB	6	*/
	7
	8	#include <linux/clk.h>
	9	#include <linux/interrupt.h>
	10	#include <linux/slab.h>
	11	#include <linux/irq.h>
	12
6579324a TB	13	#include <trace/events/host1x.h>
6579324a TB	14	#include "channel.h"
7ede0b0b TB	15	#include "dev.h"
	16	#include "intr.h"
	17
	18	/* Wait list management */
	19
	20	enum waitlist_state {
	21	WLS_PENDING,
	22	WLS_REMOVED,
	23	WLS_CANCELLED,
	24	WLS_HANDLED
	25	};
	26
	27	static void waiter_release(struct kref *kref)
	28	{
	29	kfree(container_of(kref, struct host1x_waitlist, refcount));
	30	}
	31
	32	/*
	33	* add a waiter to a waiter queue, sorted by threshold
	34	* returns true if it was added at the head of the queue
	35	*/
	36	static bool add_waiter_to_queue(struct host1x_waitlist *waiter,
	37	struct list_head *queue)
	38	{
	39	struct host1x_waitlist *pos;
	40	u32 thresh = waiter->thresh;
	41
	42	list_for_each_entry_reverse(pos, queue, list)
	43	if ((s32)(pos->thresh - thresh) <= 0) {
	44	list_add(&waiter->list, &pos->list);
	45	return false;
	46	}
	47
	48	list_add(&waiter->list, queue);
	49	return true;
	50	}
	51
	52	/*
	53	* run through a waiter queue for a single sync point ID
	54	* and gather all completed waiters into lists by actions
	55	*/
	56	static void remove_completed_waiters(struct list_head *head, u32 sync,
	57	struct list_head completed[HOST1X_INTR_ACTION_COUNT])
	58	{
	59	struct list_head *dest;
6579324a	60	struct host1x_waitlist waiter, next, *prev;
7ede0b0b TB	61
	62	list_for_each_entry_safe(waiter, next, head, list) {
	63	if ((s32)(waiter->thresh - sync) > 0)
	64	break;
	65
	66	dest = completed + waiter->action;
	67
6579324a TB	68	/* consolidate submit cleanups */
	69	if (waiter->action == HOST1X_INTR_ACTION_SUBMIT_COMPLETE &&
	70	!list_empty(dest)) {
	71	prev = list_entry(dest->prev,
	72	struct host1x_waitlist, list);
	73	if (prev->data == waiter->data) {
	74	prev->count++;
	75	dest = NULL;
	76	}
	77	}
	78
7ede0b0b TB	79	/* PENDING->REMOVED or CANCELLED->HANDLED */
	80	if (atomic_inc_return(&waiter->state) == WLS_HANDLED \|\| !dest) {
	81	list_del(&waiter->list);
	82	kref_put(&waiter->refcount, waiter_release);
	83	} else
	84	list_move_tail(&waiter->list, dest);
	85	}
	86	}
	87
	88	static void reset_threshold_interrupt(struct host1x *host,
	89	struct list_head *head,
	90	unsigned int id)
	91	{
	92	u32 thresh =
	93	list_first_entry(head, struct host1x_waitlist, list)->thresh;
	94
	95	host1x_hw_intr_set_syncpt_threshold(host, id, thresh);
	96	host1x_hw_intr_enable_syncpt_intr(host, id);
	97	}
	98
6579324a TB	99	static void action_submit_complete(struct host1x_waitlist *waiter)
	100	{
	101	struct host1x_channel *channel = waiter->data;
	102
	103	host1x_cdma_update(&channel->cdma);
	104
	105	/* Add nr_completed to trace */
	106	trace_host1x_channel_submit_complete(dev_name(channel->dev),
	107	waiter->count, waiter->thresh);
	108
	109	}
	110
7ede0b0b TB	111	static void action_wakeup(struct host1x_waitlist *waiter)
	112	{
	113	wait_queue_head_t *wq = waiter->data;
6df633d0	114
7ede0b0b TB	115	wake_up(wq);
	116	}
	117
	118	static void action_wakeup_interruptible(struct host1x_waitlist *waiter)
	119	{
	120	wait_queue_head_t *wq = waiter->data;
6df633d0	121
7ede0b0b TB	122	wake_up_interruptible(wq);
	123	}
	124
	125	typedef void (action_handler)(struct host1x_waitlist waiter);
	126
9f2e57ca	127	static const action_handler action_handlers[HOST1X_INTR_ACTION_COUNT] = {
6579324a	128	action_submit_complete,
7ede0b0b TB	129	action_wakeup,
	130	action_wakeup_interruptible,
	131	};
	132
	133	static void run_handlers(struct list_head completed[HOST1X_INTR_ACTION_COUNT])
	134	{
	135	struct list_head *head = completed;
d4ad3ad9	136	unsigned int i;
7ede0b0b TB	137
	138	for (i = 0; i < HOST1X_INTR_ACTION_COUNT; ++i, ++head) {
	139	action_handler handler = action_handlers[i];
	140	struct host1x_waitlist waiter, next;
	141
	142	list_for_each_entry_safe(waiter, next, head, list) {
	143	list_del(&waiter->list);
	144	handler(waiter);
	145	WARN_ON(atomic_xchg(&waiter->state, WLS_HANDLED) !=
	146	WLS_REMOVED);
	147	kref_put(&waiter->refcount, waiter_release);
	148	}
	149	}
	150	}
	151
	152	/*
	153	* Remove & handle all waiters that have completed for the given syncpt
	154	*/
	155	static int process_wait_list(struct host1x *host,
	156	struct host1x_syncpt *syncpt,
	157	u32 threshold)
	158	{
	159	struct list_head completed[HOST1X_INTR_ACTION_COUNT];
	160	unsigned int i;
	161	int empty;
	162
	163	for (i = 0; i < HOST1X_INTR_ACTION_COUNT; ++i)
	164	INIT_LIST_HEAD(completed + i);
	165
	166	spin_lock(&syncpt->intr.lock);
	167
	168	remove_completed_waiters(&syncpt->intr.wait_head, threshold,
	169	completed);
	170
	171	empty = list_empty(&syncpt->intr.wait_head);
	172	if (empty)
	173	host1x_hw_intr_disable_syncpt_intr(host, syncpt->id);
	174	else
	175	reset_threshold_interrupt(host, &syncpt->intr.wait_head,
	176	syncpt->id);
	177
	178	spin_unlock(&syncpt->intr.lock);
	179
	180	run_handlers(completed);
	181
	182	return empty;
	183	}
	184
	185	/*
	186	* Sync point threshold interrupt service thread function
	187	* Handles sync point threshold triggers, in thread context
	188	*/
	189
	190	static void syncpt_thresh_work(struct work_struct *work)
	191	{
	192	struct host1x_syncpt_intr *syncpt_intr =
	193	container_of(work, struct host1x_syncpt_intr, work);
	194	struct host1x_syncpt *syncpt =
	195	container_of(syncpt_intr, struct host1x_syncpt, intr);
	196	unsigned int id = syncpt->id;
	197	struct host1x *host = syncpt->host;
	198
	199	(void)process_wait_list(host, syncpt,
	200	host1x_syncpt_load(host->syncpt + id));
201	}
202
ac330f45 TR	203	int host1x_intr_add_action(struct host1x host, struct host1x_syncpt syncpt,
	204	u32 thresh, enum host1x_intr_action action,
	205	void data, struct host1x_waitlist waiter,
	206	void **ref)
7ede0b0b	207	{
7ede0b0b TB	208	int queue_was_empty;
	209
	210	if (waiter == NULL) {
	211	pr_warn("%s: NULL waiter\n", __func__);
	212	return -EINVAL;
	213	}
	214
	215	/* initialize a new waiter */
	216	INIT_LIST_HEAD(&waiter->list);
	217	kref_init(&waiter->refcount);
	218	if (ref)
	219	kref_get(&waiter->refcount);
	220	waiter->thresh = thresh;
	221	waiter->action = action;
	222	atomic_set(&waiter->state, WLS_PENDING);
	223	waiter->data = data;
	224	waiter->count = 1;
	225
7ede0b0b TB	226	spin_lock(&syncpt->intr.lock);
	227
	228	queue_was_empty = list_empty(&syncpt->intr.wait_head);
	229
	230	if (add_waiter_to_queue(waiter, &syncpt->intr.wait_head)) {
	231	/* added at head of list - new threshold value */
ac330f45	232	host1x_hw_intr_set_syncpt_threshold(host, syncpt->id, thresh);
7ede0b0b TB	233
	234	/* added as first waiter - enable interrupt */
	235	if (queue_was_empty)
ac330f45	236	host1x_hw_intr_enable_syncpt_intr(host, syncpt->id);
7ede0b0b TB	237	}
	238
	239	spin_unlock(&syncpt->intr.lock);
	240
	241	if (ref)
	242	*ref = waiter;
	243	return 0;
	244	}
	245
5c0d8d38	246	void host1x_intr_put_ref(struct host1x host, unsigned int id, void ref)
7ede0b0b TB	247	{
	248	struct host1x_waitlist *waiter = ref;
	249	struct host1x_syncpt *syncpt;
	250
	251	while (atomic_cmpxchg(&waiter->state, WLS_PENDING, WLS_CANCELLED) ==
	252	WLS_REMOVED)
	253	schedule();
	254
	255	syncpt = host->syncpt + id;
	256	(void)process_wait_list(host, syncpt,
	257	host1x_syncpt_load(host->syncpt + id));
	258
	259	kref_put(&waiter->refcount, waiter_release);
	260	}
	261
	262	int host1x_intr_init(struct host1x *host, unsigned int irq_sync)
	263	{
	264	unsigned int id;
	265	u32 nb_pts = host1x_syncpt_nb_pts(host);
	266
	267	mutex_init(&host->intr_mutex);
	268	host->intr_syncpt_irq = irq_sync;
7ede0b0b TB	269
	270	for (id = 0; id < nb_pts; ++id) {
	271	struct host1x_syncpt *syncpt = host->syncpt + id;
	272
	273	spin_lock_init(&syncpt->intr.lock);
	274	INIT_LIST_HEAD(&syncpt->intr.wait_head);
	275	snprintf(syncpt->intr.thresh_irq_name,
	276	sizeof(syncpt->intr.thresh_irq_name),
5c0d8d38	277	"host1x_sp_%02u", id);
7ede0b0b TB	278	}
	279
	280	host1x_intr_start(host);
	281
	282	return 0;
	283	}
	284
	285	void host1x_intr_deinit(struct host1x *host)
	286	{
	287	host1x_intr_stop(host);
7ede0b0b TB	288	}
	289
	290	void host1x_intr_start(struct host1x *host)
	291	{
	292	u32 hz = clk_get_rate(host->clk);
	293	int err;
	294
	295	mutex_lock(&host->intr_mutex);
	296	err = host1x_hw_intr_init_host_sync(host, DIV_ROUND_UP(hz, 1000000),
	297	syncpt_thresh_work);
	298	if (err) {
	299	mutex_unlock(&host->intr_mutex);
	300	return;
	301	}
	302	mutex_unlock(&host->intr_mutex);
	303	}
	304
	305	void host1x_intr_stop(struct host1x *host)
	306	{
	307	unsigned int id;
	308	struct host1x_syncpt *syncpt = host->syncpt;
	309	u32 nb_pts = host1x_syncpt_nb_pts(host);
	310
	311	mutex_lock(&host->intr_mutex);
	312
	313	host1x_hw_intr_disable_all_syncpt_intrs(host);
	314
	315	for (id = 0; id < nb_pts; ++id) {
	316	struct host1x_waitlist waiter, next;
	317
	318	list_for_each_entry_safe(waiter, next,
	319	&syncpt[id].intr.wait_head, list) {
	320	if (atomic_cmpxchg(&waiter->state,
	321	WLS_CANCELLED, WLS_HANDLED) == WLS_CANCELLED) {
	322	list_del(&waiter->list);
	323	kref_put(&waiter->refcount, waiter_release);
	324	}
	325	}
	326
	327	if (!list_empty(&syncpt[id].intr.wait_head)) {
	328	/* output diagnostics */
	329	mutex_unlock(&host->intr_mutex);
5c0d8d38	330	pr_warn("%s cannot stop syncpt intr id=%u\n",
7ede0b0b TB	331	__func__, id);
	332	return;
	333	}
	334	}
	335
	336	host1x_hw_intr_free_syncpt_irq(host);
	337
	338	mutex_unlock(&host->intr_mutex);
	339	}