2 * Tegra host1x Syncpoints
4 * Copyright (c) 2010-2013, NVIDIA Corporation.
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
19 #include <linux/module.h>
20 #include <linux/device.h>
21 #include <linux/slab.h>
23 #include <trace/events/host1x.h>
30 #define SYNCPT_CHECK_PERIOD (2 * HZ)
31 #define MAX_STUCK_CHECK_COUNT 15
33 static struct host1x_syncpt_base *
34 host1x_syncpt_base_request(struct host1x *host)
36 struct host1x_syncpt_base *bases = host->bases;
39 for (i = 0; i < host->info->nb_bases; i++)
40 if (!bases[i].requested)
43 if (i >= host->info->nb_bases)
46 bases[i].requested = true;
50 static void host1x_syncpt_base_free(struct host1x_syncpt_base *base)
53 base->requested = false;
56 static struct host1x_syncpt *host1x_syncpt_alloc(struct host1x *host,
61 struct host1x_syncpt *sp = host->syncpt;
64 for (i = 0; i < host->info->nb_pts && sp->name; i++, sp++)
67 if (i >= host->info->nb_pts)
70 if (flags & HOST1X_SYNCPT_HAS_BASE) {
71 sp->base = host1x_syncpt_base_request(host);
76 name = kasprintf(GFP_KERNEL, "%02d-%s", sp->id,
77 dev ? dev_name(dev) : NULL);
84 if (flags & HOST1X_SYNCPT_CLIENT_MANAGED)
85 sp->client_managed = true;
87 sp->client_managed = false;
92 u32 host1x_syncpt_id(struct host1x_syncpt *sp)
98 * Updates the value sent to hardware.
100 u32 host1x_syncpt_incr_max(struct host1x_syncpt *sp, u32 incrs)
102 return (u32)atomic_add_return(incrs, &sp->max_val);
106 * Write cached syncpoint and waitbase values to hardware.
108 void host1x_syncpt_restore(struct host1x *host)
110 struct host1x_syncpt *sp_base = host->syncpt;
113 for (i = 0; i < host1x_syncpt_nb_pts(host); i++)
114 host1x_hw_syncpt_restore(host, sp_base + i);
115 for (i = 0; i < host1x_syncpt_nb_bases(host); i++)
116 host1x_hw_syncpt_restore_wait_base(host, sp_base + i);
121 * Update the cached syncpoint and waitbase values by reading them
122 * from the registers.
124 void host1x_syncpt_save(struct host1x *host)
126 struct host1x_syncpt *sp_base = host->syncpt;
129 for (i = 0; i < host1x_syncpt_nb_pts(host); i++) {
130 if (host1x_syncpt_client_managed(sp_base + i))
131 host1x_hw_syncpt_load(host, sp_base + i);
133 WARN_ON(!host1x_syncpt_idle(sp_base + i));
136 for (i = 0; i < host1x_syncpt_nb_bases(host); i++)
137 host1x_hw_syncpt_load_wait_base(host, sp_base + i);
141 * Updates the cached syncpoint value by reading a new value from the hardware
144 u32 host1x_syncpt_load(struct host1x_syncpt *sp)
147 val = host1x_hw_syncpt_load(sp->host, sp);
148 trace_host1x_syncpt_load_min(sp->id, val);
154 * Get the current syncpoint base
156 u32 host1x_syncpt_load_wait_base(struct host1x_syncpt *sp)
159 host1x_hw_syncpt_load_wait_base(sp->host, sp);
165 * Increment syncpoint value from cpu, updating cache
167 int host1x_syncpt_incr(struct host1x_syncpt *sp)
169 return host1x_hw_syncpt_cpu_incr(sp->host, sp);
173 * Updated sync point form hardware, and returns true if syncpoint is expired,
174 * false if we may need to wait
176 static bool syncpt_load_min_is_expired(struct host1x_syncpt *sp, u32 thresh)
178 host1x_hw_syncpt_load(sp->host, sp);
179 return host1x_syncpt_is_expired(sp, thresh);
183 * Main entrypoint for syncpoint value waits.
185 int host1x_syncpt_wait(struct host1x_syncpt *sp, u32 thresh, long timeout,
188 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
190 struct host1x_waitlist *waiter;
191 int err = 0, check_count = 0;
197 /* first check cache */
198 if (host1x_syncpt_is_expired(sp, thresh)) {
200 *value = host1x_syncpt_load(sp);
204 /* try to read from register */
205 val = host1x_hw_syncpt_load(sp->host, sp);
206 if (host1x_syncpt_is_expired(sp, thresh)) {
217 /* allocate a waiter */
218 waiter = kzalloc(sizeof(*waiter), GFP_KERNEL);
224 /* schedule a wakeup when the syncpoint value is reached */
225 err = host1x_intr_add_action(sp->host, sp->id, thresh,
226 HOST1X_INTR_ACTION_WAKEUP_INTERRUPTIBLE,
232 /* Caller-specified timeout may be impractically low */
236 /* wait for the syncpoint, or timeout, or signal */
238 long check = min_t(long, SYNCPT_CHECK_PERIOD, timeout);
239 int remain = wait_event_interruptible_timeout(wq,
240 syncpt_load_min_is_expired(sp, thresh),
242 if (remain > 0 || host1x_syncpt_is_expired(sp, thresh)) {
244 *value = host1x_syncpt_load(sp);
253 if (timeout && check_count <= MAX_STUCK_CHECK_COUNT) {
254 dev_warn(sp->host->dev,
255 "%s: syncpoint id %d (%s) stuck waiting %d, timeout=%ld\n",
256 current->comm, sp->id, sp->name,
259 host1x_debug_dump_syncpts(sp->host);
260 if (check_count == MAX_STUCK_CHECK_COUNT)
261 host1x_debug_dump(sp->host);
265 host1x_intr_put_ref(sp->host, sp->id, ref);
270 EXPORT_SYMBOL(host1x_syncpt_wait);
273 * Returns true if syncpoint is expired, false if we may need to wait
275 bool host1x_syncpt_is_expired(struct host1x_syncpt *sp, u32 thresh)
280 current_val = (u32)atomic_read(&sp->min_val);
281 future_val = (u32)atomic_read(&sp->max_val);
283 /* Note the use of unsigned arithmetic here (mod 1<<32).
285 * c = current_val = min_val = the current value of the syncpoint.
286 * t = thresh = the value we are checking
287 * f = future_val = max_val = the value c will reach when all
288 * outstanding increments have completed.
290 * Note that c always chases f until it reaches f.
295 * Consider all cases:
297 * A) .....c..t..f..... Dtf < Dtc need to wait
298 * B) .....c.....f..t.. Dtf > Dtc expired
299 * C) ..t..c.....f..... Dtf > Dtc expired (Dct very large)
301 * Any case where f==c: always expired (for any t). Dtf == Dcf
302 * Any case where t==c: always expired (for any f). Dtf >= Dtc (because Dtc==0)
303 * Any case where t==f!=c: always wait. Dtf < Dtc (because Dtf==0,
308 * A) .....t..f..c..... Dtf < Dtc need to wait
309 * A) .....f..c..t..... Dtf < Dtc need to wait
310 * A) .....f..t..c..... Dtf > Dtc expired
313 * Dtf >= Dtc implies EXPIRED (return true)
314 * Dtf < Dtc implies WAIT (return false)
316 * Note: If t is expired then we *cannot* wait on it. We would wait
317 * forever (hang the system).
319 * Note: do NOT get clever and remove the -thresh from both sides. It
322 * If future valueis zero, we have a client managed sync point. In that
323 * case we do a direct comparison.
325 if (!host1x_syncpt_client_managed(sp))
326 return future_val - thresh >= current_val - thresh;
328 return (s32)(current_val - thresh) >= 0;
331 /* remove a wait pointed to by patch_addr */
332 int host1x_syncpt_patch_wait(struct host1x_syncpt *sp, void *patch_addr)
334 return host1x_hw_syncpt_patch_wait(sp->host, sp, patch_addr);
337 int host1x_syncpt_init(struct host1x *host)
339 struct host1x_syncpt_base *bases;
340 struct host1x_syncpt *syncpt;
343 syncpt = devm_kzalloc(host->dev, sizeof(*syncpt) * host->info->nb_pts,
348 bases = devm_kzalloc(host->dev, sizeof(*bases) * host->info->nb_bases,
353 for (i = 0; i < host->info->nb_pts; i++) {
355 syncpt[i].host = host;
358 for (i = 0; i < host->info->nb_bases; i++)
361 host->syncpt = syncpt;
364 host1x_syncpt_restore(host);
366 /* Allocate sync point to use for clearing waits for expired fences */
367 host->nop_sp = host1x_syncpt_alloc(host, NULL, 0);
374 struct host1x_syncpt *host1x_syncpt_request(struct device *dev,
377 struct host1x *host = dev_get_drvdata(dev->parent);
378 return host1x_syncpt_alloc(host, dev, flags);
381 void host1x_syncpt_free(struct host1x_syncpt *sp)
386 host1x_syncpt_base_free(sp->base);
391 sp->client_managed = false;
394 void host1x_syncpt_deinit(struct host1x *host)
397 struct host1x_syncpt *sp = host->syncpt;
398 for (i = 0; i < host->info->nb_pts; i++, sp++)
403 * Read max. It indicates how many operations there are in queue, either in
404 * channel or in a software thread.
406 u32 host1x_syncpt_read_max(struct host1x_syncpt *sp)
409 return (u32)atomic_read(&sp->max_val);
413 * Read min, which is a shadow of the current sync point value in hardware.
415 u32 host1x_syncpt_read_min(struct host1x_syncpt *sp)
418 return (u32)atomic_read(&sp->min_val);
421 int host1x_syncpt_nb_pts(struct host1x *host)
423 return host->info->nb_pts;
426 int host1x_syncpt_nb_bases(struct host1x *host)
428 return host->info->nb_bases;
431 int host1x_syncpt_nb_mlocks(struct host1x *host)
433 return host->info->nb_mlocks;
436 struct host1x_syncpt *host1x_syncpt_get(struct host1x *host, u32 id)
438 if (host->info->nb_pts < id)
440 return host->syncpt + id;
443 struct host1x_syncpt_base *host1x_syncpt_get_base(struct host1x_syncpt *sp)
445 return sp ? sp->base : NULL;
448 u32 host1x_syncpt_base_id(struct host1x_syncpt_base *base)