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/dma-fence.h>
11 #include <linux/slab.h>
13 #include <trace/events/host1x.h>
20 #define SYNCPT_CHECK_PERIOD (2 * HZ)
21 #define MAX_STUCK_CHECK_COUNT 15
23 static struct host1x_syncpt_base *
24 host1x_syncpt_base_request(struct host1x *host)
26 struct host1x_syncpt_base *bases = host->bases;
29 for (i = 0; i < host->info->nb_bases; i++)
30 if (!bases[i].requested)
33 if (i >= host->info->nb_bases)
36 bases[i].requested = true;
40 static void host1x_syncpt_base_free(struct host1x_syncpt_base *base)
43 base->requested = false;
47 * host1x_syncpt_alloc() - allocate a syncpoint
48 * @host: host1x device data
49 * @flags: bitfield of HOST1X_SYNCPT_* flags
50 * @name: name for the syncpoint for use in debug prints
52 * Allocates a hardware syncpoint for the caller's use. The caller then has
53 * the sole authority to mutate the syncpoint's value until it is freed again.
55 * If no free syncpoints are available, or a NULL name was specified, returns
58 struct host1x_syncpt *host1x_syncpt_alloc(struct host1x *host,
62 struct host1x_syncpt *sp = host->syncpt;
69 mutex_lock(&host->syncpt_mutex);
71 for (i = 0; i < host->info->nb_pts && kref_read(&sp->ref); i++, sp++)
74 if (i >= host->info->nb_pts)
77 if (flags & HOST1X_SYNCPT_HAS_BASE) {
78 sp->base = host1x_syncpt_base_request(host);
83 full_name = kasprintf(GFP_KERNEL, "%u-%s", sp->id, name);
89 if (flags & HOST1X_SYNCPT_CLIENT_MANAGED)
90 sp->client_managed = true;
92 sp->client_managed = false;
96 mutex_unlock(&host->syncpt_mutex);
100 host1x_syncpt_base_free(sp->base);
103 mutex_unlock(&host->syncpt_mutex);
106 EXPORT_SYMBOL(host1x_syncpt_alloc);
109 * host1x_syncpt_id() - retrieve syncpoint ID
110 * @sp: host1x syncpoint
112 * Given a pointer to a struct host1x_syncpt, retrieves its ID. This ID is
113 * often used as a value to program into registers that control how hardware
114 * blocks interact with syncpoints.
116 u32 host1x_syncpt_id(struct host1x_syncpt *sp)
120 EXPORT_SYMBOL(host1x_syncpt_id);
123 * host1x_syncpt_incr_max() - update the value sent to hardware
124 * @sp: host1x syncpoint
125 * @incrs: number of increments
127 u32 host1x_syncpt_incr_max(struct host1x_syncpt *sp, u32 incrs)
129 return (u32)atomic_add_return(incrs, &sp->max_val);
131 EXPORT_SYMBOL(host1x_syncpt_incr_max);
134 * Write cached syncpoint and waitbase values to hardware.
136 void host1x_syncpt_restore(struct host1x *host)
138 struct host1x_syncpt *sp_base = host->syncpt;
141 for (i = 0; i < host1x_syncpt_nb_pts(host); i++) {
143 * Unassign syncpt from channels for purposes of Tegra186
144 * syncpoint protection. This prevents any channel from
145 * accessing it until it is reassigned.
147 host1x_hw_syncpt_assign_to_channel(host, sp_base + i, NULL);
148 host1x_hw_syncpt_restore(host, sp_base + i);
151 for (i = 0; i < host1x_syncpt_nb_bases(host); i++)
152 host1x_hw_syncpt_restore_wait_base(host, sp_base + i);
154 host1x_hw_syncpt_enable_protection(host);
160 * Update the cached syncpoint and waitbase values by reading them
161 * from the registers.
163 void host1x_syncpt_save(struct host1x *host)
165 struct host1x_syncpt *sp_base = host->syncpt;
168 for (i = 0; i < host1x_syncpt_nb_pts(host); i++) {
169 if (host1x_syncpt_client_managed(sp_base + i))
170 host1x_hw_syncpt_load(host, sp_base + i);
172 WARN_ON(!host1x_syncpt_idle(sp_base + i));
175 for (i = 0; i < host1x_syncpt_nb_bases(host); i++)
176 host1x_hw_syncpt_load_wait_base(host, sp_base + i);
180 * Updates the cached syncpoint value by reading a new value from the hardware
183 u32 host1x_syncpt_load(struct host1x_syncpt *sp)
187 val = host1x_hw_syncpt_load(sp->host, sp);
188 trace_host1x_syncpt_load_min(sp->id, val);
194 * Get the current syncpoint base
196 u32 host1x_syncpt_load_wait_base(struct host1x_syncpt *sp)
198 host1x_hw_syncpt_load_wait_base(sp->host, sp);
204 * host1x_syncpt_incr() - increment syncpoint value from CPU, updating cache
205 * @sp: host1x syncpoint
207 int host1x_syncpt_incr(struct host1x_syncpt *sp)
209 return host1x_hw_syncpt_cpu_incr(sp->host, sp);
211 EXPORT_SYMBOL(host1x_syncpt_incr);
214 * host1x_syncpt_wait() - wait for a syncpoint to reach a given value
215 * @sp: host1x syncpoint
217 * @timeout: maximum time to wait for the syncpoint to reach the given value
218 * @value: return location for the syncpoint value
220 int host1x_syncpt_wait(struct host1x_syncpt *sp, u32 thresh, long timeout,
223 struct dma_fence *fence;
226 host1x_hw_syncpt_load(sp->host, sp);
229 *value = host1x_syncpt_load(sp);
231 if (host1x_syncpt_is_expired(sp, thresh))
236 else if (timeout == 0)
239 fence = host1x_fence_create(sp, thresh, false);
241 return PTR_ERR(fence);
243 wait_err = dma_fence_wait_timeout(fence, true, timeout);
245 host1x_fence_cancel(fence);
246 dma_fence_put(fence);
249 *value = host1x_syncpt_load(sp);
252 * Don't rely on dma_fence_wait_timeout return value,
253 * since it returns zero both on timeout and if the
254 * wait completed with 0 jiffies left.
256 host1x_hw_syncpt_load(sp->host, sp);
257 if (wait_err == 0 && !host1x_syncpt_is_expired(sp, thresh))
259 else if (wait_err < 0)
264 EXPORT_SYMBOL(host1x_syncpt_wait);
267 * Returns true if syncpoint is expired, false if we may need to wait
269 bool host1x_syncpt_is_expired(struct host1x_syncpt *sp, u32 thresh)
275 current_val = (u32)atomic_read(&sp->min_val);
277 return ((current_val - thresh) & 0x80000000U) == 0U;
280 int host1x_syncpt_init(struct host1x *host)
282 struct host1x_syncpt_base *bases;
283 struct host1x_syncpt *syncpt;
286 syncpt = devm_kcalloc(host->dev, host->info->nb_pts, sizeof(*syncpt),
291 bases = devm_kcalloc(host->dev, host->info->nb_bases, sizeof(*bases),
296 for (i = 0; i < host->info->nb_pts; i++) {
298 syncpt[i].host = host;
301 for (i = 0; i < host->info->nb_bases; i++)
304 mutex_init(&host->syncpt_mutex);
305 host->syncpt = syncpt;
308 /* Allocate sync point to use for clearing waits for expired fences */
309 host->nop_sp = host1x_syncpt_alloc(host, 0, "reserved-nop");
313 if (host->info->reserve_vblank_syncpts) {
314 kref_init(&host->syncpt[26].ref);
315 kref_init(&host->syncpt[27].ref);
322 * host1x_syncpt_request() - request a syncpoint
323 * @client: client requesting the syncpoint
326 * host1x client drivers can use this function to allocate a syncpoint for
327 * subsequent use. A syncpoint returned by this function will be reserved for
328 * use by the client exclusively. When no longer using a syncpoint, a host1x
329 * client driver needs to release it using host1x_syncpt_put().
331 struct host1x_syncpt *host1x_syncpt_request(struct host1x_client *client,
334 struct host1x *host = dev_get_drvdata(client->host->parent);
336 return host1x_syncpt_alloc(host, flags, dev_name(client->dev));
338 EXPORT_SYMBOL(host1x_syncpt_request);
340 static void syncpt_release(struct kref *ref)
342 struct host1x_syncpt *sp = container_of(ref, struct host1x_syncpt, ref);
344 atomic_set(&sp->max_val, host1x_syncpt_read(sp));
348 mutex_lock(&sp->host->syncpt_mutex);
350 host1x_syncpt_base_free(sp->base);
354 sp->client_managed = false;
356 mutex_unlock(&sp->host->syncpt_mutex);
360 * host1x_syncpt_put() - free a requested syncpoint
361 * @sp: host1x syncpoint
363 * Release a syncpoint previously allocated using host1x_syncpt_request(). A
364 * host1x client driver should call this when the syncpoint is no longer in
367 void host1x_syncpt_put(struct host1x_syncpt *sp)
372 kref_put(&sp->ref, syncpt_release);
374 EXPORT_SYMBOL(host1x_syncpt_put);
376 void host1x_syncpt_deinit(struct host1x *host)
378 struct host1x_syncpt *sp = host->syncpt;
381 for (i = 0; i < host->info->nb_pts; i++, sp++)
386 * host1x_syncpt_read_max() - read maximum syncpoint value
387 * @sp: host1x syncpoint
389 * The maximum syncpoint value indicates how many operations there are in
390 * queue, either in channel or in a software thread.
392 u32 host1x_syncpt_read_max(struct host1x_syncpt *sp)
396 return (u32)atomic_read(&sp->max_val);
398 EXPORT_SYMBOL(host1x_syncpt_read_max);
401 * host1x_syncpt_read_min() - read minimum syncpoint value
402 * @sp: host1x syncpoint
404 * The minimum syncpoint value is a shadow of the current sync point value in
407 u32 host1x_syncpt_read_min(struct host1x_syncpt *sp)
411 return (u32)atomic_read(&sp->min_val);
413 EXPORT_SYMBOL(host1x_syncpt_read_min);
416 * host1x_syncpt_read() - read the current syncpoint value
417 * @sp: host1x syncpoint
419 u32 host1x_syncpt_read(struct host1x_syncpt *sp)
421 return host1x_syncpt_load(sp);
423 EXPORT_SYMBOL(host1x_syncpt_read);
425 unsigned int host1x_syncpt_nb_pts(struct host1x *host)
427 return host->info->nb_pts;
430 unsigned int host1x_syncpt_nb_bases(struct host1x *host)
432 return host->info->nb_bases;
435 unsigned int host1x_syncpt_nb_mlocks(struct host1x *host)
437 return host->info->nb_mlocks;
441 * host1x_syncpt_get_by_id() - obtain a syncpoint by ID
442 * @host: host1x controller
445 struct host1x_syncpt *host1x_syncpt_get_by_id(struct host1x *host,
448 if (id >= host->info->nb_pts)
451 if (kref_get_unless_zero(&host->syncpt[id].ref))
452 return &host->syncpt[id];
456 EXPORT_SYMBOL(host1x_syncpt_get_by_id);
459 * host1x_syncpt_get_by_id_noref() - obtain a syncpoint by ID but don't
460 * increase the refcount.
461 * @host: host1x controller
464 struct host1x_syncpt *host1x_syncpt_get_by_id_noref(struct host1x *host,
467 if (id >= host->info->nb_pts)
470 return &host->syncpt[id];
472 EXPORT_SYMBOL(host1x_syncpt_get_by_id_noref);
475 * host1x_syncpt_get() - increment syncpoint refcount
478 struct host1x_syncpt *host1x_syncpt_get(struct host1x_syncpt *sp)
484 EXPORT_SYMBOL(host1x_syncpt_get);
487 * host1x_syncpt_get_base() - obtain the wait base associated with a syncpoint
488 * @sp: host1x syncpoint
490 struct host1x_syncpt_base *host1x_syncpt_get_base(struct host1x_syncpt *sp)
492 return sp ? sp->base : NULL;
494 EXPORT_SYMBOL(host1x_syncpt_get_base);
497 * host1x_syncpt_base_id() - retrieve the ID of a syncpoint wait base
498 * @base: host1x syncpoint wait base
500 u32 host1x_syncpt_base_id(struct host1x_syncpt_base *base)
504 EXPORT_SYMBOL(host1x_syncpt_base_id);
506 static void do_nothing(struct kref *ref)
511 * host1x_syncpt_release_vblank_reservation() - Make VBLANK syncpoint
512 * available for allocation
514 * @client: host1x bus client
515 * @syncpt_id: syncpoint ID to make available
517 * Makes VBLANK<i> syncpoint available for allocatation if it was
518 * reserved at initialization time. This should be called by the display
519 * driver after it has ensured that any VBLANK increment programming configured
520 * by the boot chain has been disabled.
522 void host1x_syncpt_release_vblank_reservation(struct host1x_client *client,
525 struct host1x *host = dev_get_drvdata(client->host->parent);
527 if (!host->info->reserve_vblank_syncpts)
530 kref_put(&host->syncpt[syncpt_id].ref, do_nothing);
532 EXPORT_SYMBOL(host1x_syncpt_release_vblank_reservation);