1 // SPDX-License-Identifier: GPL-2.0-only
3 * Tegra host1x Syncpoints
5 * Copyright (c) 2010-2015, NVIDIA Corporation.
8 #include <linux/module.h>
9 #include <linux/device.h>
10 #include <linux/slab.h>
12 #include <trace/events/host1x.h>
19 #define SYNCPT_CHECK_PERIOD (2 * HZ)
20 #define MAX_STUCK_CHECK_COUNT 15
22 static struct host1x_syncpt_base *
23 host1x_syncpt_base_request(struct host1x *host)
25 struct host1x_syncpt_base *bases = host->bases;
28 for (i = 0; i < host->info->nb_bases; i++)
29 if (!bases[i].requested)
32 if (i >= host->info->nb_bases)
35 bases[i].requested = true;
39 static void host1x_syncpt_base_free(struct host1x_syncpt_base *base)
42 base->requested = false;
46 * host1x_syncpt_alloc() - allocate a syncpoint
47 * @host: host1x device data
48 * @flags: bitfield of HOST1X_SYNCPT_* flags
49 * @name: name for the syncpoint for use in debug prints
51 * Allocates a hardware syncpoint for the caller's use. The caller then has
52 * the sole authority to mutate the syncpoint's value until it is freed again.
54 * If no free syncpoints are available, or a NULL name was specified, returns
57 struct host1x_syncpt *host1x_syncpt_alloc(struct host1x *host,
61 struct host1x_syncpt *sp = host->syncpt;
68 mutex_lock(&host->syncpt_mutex);
70 for (i = 0; i < host->info->nb_pts && kref_read(&sp->ref); i++, sp++)
73 if (i >= host->info->nb_pts)
76 if (flags & HOST1X_SYNCPT_HAS_BASE) {
77 sp->base = host1x_syncpt_base_request(host);
82 full_name = kasprintf(GFP_KERNEL, "%u-%s", sp->id, name);
88 if (flags & HOST1X_SYNCPT_CLIENT_MANAGED)
89 sp->client_managed = true;
91 sp->client_managed = false;
95 mutex_unlock(&host->syncpt_mutex);
99 host1x_syncpt_base_free(sp->base);
102 mutex_unlock(&host->syncpt_mutex);
105 EXPORT_SYMBOL(host1x_syncpt_alloc);
108 * host1x_syncpt_id() - retrieve syncpoint ID
109 * @sp: host1x syncpoint
111 * Given a pointer to a struct host1x_syncpt, retrieves its ID. This ID is
112 * often used as a value to program into registers that control how hardware
113 * blocks interact with syncpoints.
115 u32 host1x_syncpt_id(struct host1x_syncpt *sp)
119 EXPORT_SYMBOL(host1x_syncpt_id);
122 * host1x_syncpt_incr_max() - update the value sent to hardware
123 * @sp: host1x syncpoint
124 * @incrs: number of increments
126 u32 host1x_syncpt_incr_max(struct host1x_syncpt *sp, u32 incrs)
128 return (u32)atomic_add_return(incrs, &sp->max_val);
130 EXPORT_SYMBOL(host1x_syncpt_incr_max);
133 * Write cached syncpoint and waitbase values to hardware.
135 void host1x_syncpt_restore(struct host1x *host)
137 struct host1x_syncpt *sp_base = host->syncpt;
140 for (i = 0; i < host1x_syncpt_nb_pts(host); i++) {
142 * Unassign syncpt from channels for purposes of Tegra186
143 * syncpoint protection. This prevents any channel from
144 * accessing it until it is reassigned.
146 host1x_hw_syncpt_assign_to_channel(host, sp_base + i, NULL);
147 host1x_hw_syncpt_restore(host, sp_base + i);
150 for (i = 0; i < host1x_syncpt_nb_bases(host); i++)
151 host1x_hw_syncpt_restore_wait_base(host, sp_base + i);
153 host1x_hw_syncpt_enable_protection(host);
159 * Update the cached syncpoint and waitbase values by reading them
160 * from the registers.
162 void host1x_syncpt_save(struct host1x *host)
164 struct host1x_syncpt *sp_base = host->syncpt;
167 for (i = 0; i < host1x_syncpt_nb_pts(host); i++) {
168 if (host1x_syncpt_client_managed(sp_base + i))
169 host1x_hw_syncpt_load(host, sp_base + i);
171 WARN_ON(!host1x_syncpt_idle(sp_base + i));
174 for (i = 0; i < host1x_syncpt_nb_bases(host); i++)
175 host1x_hw_syncpt_load_wait_base(host, sp_base + i);
179 * Updates the cached syncpoint value by reading a new value from the hardware
182 u32 host1x_syncpt_load(struct host1x_syncpt *sp)
186 val = host1x_hw_syncpt_load(sp->host, sp);
187 trace_host1x_syncpt_load_min(sp->id, val);
193 * Get the current syncpoint base
195 u32 host1x_syncpt_load_wait_base(struct host1x_syncpt *sp)
197 host1x_hw_syncpt_load_wait_base(sp->host, sp);
203 * host1x_syncpt_incr() - increment syncpoint value from CPU, updating cache
204 * @sp: host1x syncpoint
206 int host1x_syncpt_incr(struct host1x_syncpt *sp)
208 return host1x_hw_syncpt_cpu_incr(sp->host, sp);
210 EXPORT_SYMBOL(host1x_syncpt_incr);
213 * Updated sync point form hardware, and returns true if syncpoint is expired,
214 * false if we may need to wait
216 static bool syncpt_load_min_is_expired(struct host1x_syncpt *sp, u32 thresh)
218 host1x_hw_syncpt_load(sp->host, sp);
220 return host1x_syncpt_is_expired(sp, thresh);
224 * host1x_syncpt_wait() - wait for a syncpoint to reach a given value
225 * @sp: host1x syncpoint
227 * @timeout: maximum time to wait for the syncpoint to reach the given value
228 * @value: return location for the syncpoint value
230 int host1x_syncpt_wait(struct host1x_syncpt *sp, u32 thresh, long timeout,
233 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
235 struct host1x_waitlist *waiter;
236 int err = 0, check_count = 0;
239 *value = host1x_syncpt_load(sp);
241 if (host1x_syncpt_is_expired(sp, thresh))
249 /* allocate a waiter */
250 waiter = kzalloc(sizeof(*waiter), GFP_KERNEL);
256 /* schedule a wakeup when the syncpoint value is reached */
257 err = host1x_intr_add_action(sp->host, sp, thresh,
258 HOST1X_INTR_ACTION_WAKEUP_INTERRUPTIBLE,
264 /* Caller-specified timeout may be impractically low */
268 /* wait for the syncpoint, or timeout, or signal */
270 long check = min_t(long, SYNCPT_CHECK_PERIOD, timeout);
273 remain = wait_event_interruptible_timeout(wq,
274 syncpt_load_min_is_expired(sp, thresh),
276 if (remain > 0 || host1x_syncpt_is_expired(sp, thresh)) {
278 *value = host1x_syncpt_load(sp);
292 if (timeout && check_count <= MAX_STUCK_CHECK_COUNT) {
293 dev_warn(sp->host->dev,
294 "%s: syncpoint id %u (%s) stuck waiting %d, timeout=%ld\n",
295 current->comm, sp->id, sp->name,
298 host1x_debug_dump_syncpts(sp->host);
300 if (check_count == MAX_STUCK_CHECK_COUNT)
301 host1x_debug_dump(sp->host);
307 host1x_intr_put_ref(sp->host, sp->id, ref, true);
312 EXPORT_SYMBOL(host1x_syncpt_wait);
315 * Returns true if syncpoint is expired, false if we may need to wait
317 bool host1x_syncpt_is_expired(struct host1x_syncpt *sp, u32 thresh)
323 current_val = (u32)atomic_read(&sp->min_val);
325 return ((current_val - thresh) & 0x80000000U) == 0U;
328 int host1x_syncpt_init(struct host1x *host)
330 struct host1x_syncpt_base *bases;
331 struct host1x_syncpt *syncpt;
334 syncpt = devm_kcalloc(host->dev, host->info->nb_pts, sizeof(*syncpt),
339 bases = devm_kcalloc(host->dev, host->info->nb_bases, sizeof(*bases),
344 for (i = 0; i < host->info->nb_pts; i++) {
346 syncpt[i].host = host;
349 for (i = 0; i < host->info->nb_bases; i++)
352 mutex_init(&host->syncpt_mutex);
353 host->syncpt = syncpt;
356 /* Allocate sync point to use for clearing waits for expired fences */
357 host->nop_sp = host1x_syncpt_alloc(host, 0, "reserved-nop");
361 if (host->info->reserve_vblank_syncpts) {
362 kref_init(&host->syncpt[26].ref);
363 kref_init(&host->syncpt[27].ref);
370 * host1x_syncpt_request() - request a syncpoint
371 * @client: client requesting the syncpoint
374 * host1x client drivers can use this function to allocate a syncpoint for
375 * subsequent use. A syncpoint returned by this function will be reserved for
376 * use by the client exclusively. When no longer using a syncpoint, a host1x
377 * client driver needs to release it using host1x_syncpt_put().
379 struct host1x_syncpt *host1x_syncpt_request(struct host1x_client *client,
382 struct host1x *host = dev_get_drvdata(client->host->parent);
384 return host1x_syncpt_alloc(host, flags, dev_name(client->dev));
386 EXPORT_SYMBOL(host1x_syncpt_request);
388 static void syncpt_release(struct kref *ref)
390 struct host1x_syncpt *sp = container_of(ref, struct host1x_syncpt, ref);
392 atomic_set(&sp->max_val, host1x_syncpt_read(sp));
396 mutex_lock(&sp->host->syncpt_mutex);
398 host1x_syncpt_base_free(sp->base);
402 sp->client_managed = false;
404 mutex_unlock(&sp->host->syncpt_mutex);
408 * host1x_syncpt_put() - free a requested syncpoint
409 * @sp: host1x syncpoint
411 * Release a syncpoint previously allocated using host1x_syncpt_request(). A
412 * host1x client driver should call this when the syncpoint is no longer in
415 void host1x_syncpt_put(struct host1x_syncpt *sp)
420 kref_put(&sp->ref, syncpt_release);
422 EXPORT_SYMBOL(host1x_syncpt_put);
424 void host1x_syncpt_deinit(struct host1x *host)
426 struct host1x_syncpt *sp = host->syncpt;
429 for (i = 0; i < host->info->nb_pts; i++, sp++)
434 * host1x_syncpt_read_max() - read maximum syncpoint value
435 * @sp: host1x syncpoint
437 * The maximum syncpoint value indicates how many operations there are in
438 * queue, either in channel or in a software thread.
440 u32 host1x_syncpt_read_max(struct host1x_syncpt *sp)
444 return (u32)atomic_read(&sp->max_val);
446 EXPORT_SYMBOL(host1x_syncpt_read_max);
449 * host1x_syncpt_read_min() - read minimum syncpoint value
450 * @sp: host1x syncpoint
452 * The minimum syncpoint value is a shadow of the current sync point value in
455 u32 host1x_syncpt_read_min(struct host1x_syncpt *sp)
459 return (u32)atomic_read(&sp->min_val);
461 EXPORT_SYMBOL(host1x_syncpt_read_min);
464 * host1x_syncpt_read() - read the current syncpoint value
465 * @sp: host1x syncpoint
467 u32 host1x_syncpt_read(struct host1x_syncpt *sp)
469 return host1x_syncpt_load(sp);
471 EXPORT_SYMBOL(host1x_syncpt_read);
473 unsigned int host1x_syncpt_nb_pts(struct host1x *host)
475 return host->info->nb_pts;
478 unsigned int host1x_syncpt_nb_bases(struct host1x *host)
480 return host->info->nb_bases;
483 unsigned int host1x_syncpt_nb_mlocks(struct host1x *host)
485 return host->info->nb_mlocks;
489 * host1x_syncpt_get_by_id() - obtain a syncpoint by ID
490 * @host: host1x controller
493 struct host1x_syncpt *host1x_syncpt_get_by_id(struct host1x *host,
496 if (id >= host->info->nb_pts)
499 if (kref_get_unless_zero(&host->syncpt[id].ref))
500 return &host->syncpt[id];
504 EXPORT_SYMBOL(host1x_syncpt_get_by_id);
507 * host1x_syncpt_get_by_id_noref() - obtain a syncpoint by ID but don't
508 * increase the refcount.
509 * @host: host1x controller
512 struct host1x_syncpt *host1x_syncpt_get_by_id_noref(struct host1x *host,
515 if (id >= host->info->nb_pts)
518 return &host->syncpt[id];
520 EXPORT_SYMBOL(host1x_syncpt_get_by_id_noref);
523 * host1x_syncpt_get() - increment syncpoint refcount
526 struct host1x_syncpt *host1x_syncpt_get(struct host1x_syncpt *sp)
532 EXPORT_SYMBOL(host1x_syncpt_get);
535 * host1x_syncpt_get_base() - obtain the wait base associated with a syncpoint
536 * @sp: host1x syncpoint
538 struct host1x_syncpt_base *host1x_syncpt_get_base(struct host1x_syncpt *sp)
540 return sp ? sp->base : NULL;
542 EXPORT_SYMBOL(host1x_syncpt_get_base);
545 * host1x_syncpt_base_id() - retrieve the ID of a syncpoint wait base
546 * @base: host1x syncpoint wait base
548 u32 host1x_syncpt_base_id(struct host1x_syncpt_base *base)
552 EXPORT_SYMBOL(host1x_syncpt_base_id);
554 static void do_nothing(struct kref *ref)
559 * host1x_syncpt_release_vblank_reservation() - Make VBLANK syncpoint
560 * available for allocation
562 * @client: host1x bus client
563 * @syncpt_id: syncpoint ID to make available
565 * Makes VBLANK<i> syncpoint available for allocatation if it was
566 * reserved at initialization time. This should be called by the display
567 * driver after it has ensured that any VBLANK increment programming configured
568 * by the boot chain has been disabled.
570 void host1x_syncpt_release_vblank_reservation(struct host1x_client *client,
573 struct host1x *host = dev_get_drvdata(client->host->parent);
575 if (!host->info->reserve_vblank_syncpts)
578 kref_put(&host->syncpt[syncpt_id].ref, do_nothing);
580 EXPORT_SYMBOL(host1x_syncpt_release_vblank_reservation);