diff options
Diffstat (limited to 'kernel/drivers/gpu/host1x/syncpt.c')
| -rw-r--r-- | kernel/drivers/gpu/host1x/syncpt.c | 467 |
1 files changed, 467 insertions, 0 deletions
diff --git a/kernel/drivers/gpu/host1x/syncpt.c b/kernel/drivers/gpu/host1x/syncpt.c new file mode 100644 index 000000000..6b7fdc1e2 --- /dev/null +++ b/kernel/drivers/gpu/host1x/syncpt.c @@ -0,0 +1,467 @@ +/* + * Tegra host1x Syncpoints + * + * Copyright (c) 2010-2013, NVIDIA Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/module.h> +#include <linux/device.h> +#include <linux/slab.h> + +#include <trace/events/host1x.h> + +#include "syncpt.h" +#include "dev.h" +#include "intr.h" +#include "debug.h" + +#define SYNCPT_CHECK_PERIOD (2 * HZ) +#define MAX_STUCK_CHECK_COUNT 15 + +static struct host1x_syncpt_base * +host1x_syncpt_base_request(struct host1x *host) +{ + struct host1x_syncpt_base *bases = host->bases; + unsigned int i; + + for (i = 0; i < host->info->nb_bases; i++) + if (!bases[i].requested) + break; + + if (i >= host->info->nb_bases) + return NULL; + + bases[i].requested = true; + return &bases[i]; +} + +static void host1x_syncpt_base_free(struct host1x_syncpt_base *base) +{ + if (base) + base->requested = false; +} + +static struct host1x_syncpt *host1x_syncpt_alloc(struct host1x *host, + struct device *dev, + unsigned long flags) +{ + int i; + struct host1x_syncpt *sp = host->syncpt; + char *name; + + for (i = 0; i < host->info->nb_pts && sp->name; i++, sp++) + ; + + if (i >= host->info->nb_pts) + return NULL; + + if (flags & HOST1X_SYNCPT_HAS_BASE) { + sp->base = host1x_syncpt_base_request(host); + if (!sp->base) + return NULL; + } + + name = kasprintf(GFP_KERNEL, "%02d-%s", sp->id, + dev ? dev_name(dev) : NULL); + if (!name) + return NULL; + + sp->dev = dev; + sp->name = name; + + if (flags & HOST1X_SYNCPT_CLIENT_MANAGED) + sp->client_managed = true; + else + sp->client_managed = false; + + return sp; +} + +u32 host1x_syncpt_id(struct host1x_syncpt *sp) +{ + return sp->id; +} +EXPORT_SYMBOL(host1x_syncpt_id); + +/* + * Updates the value sent to hardware. + */ +u32 host1x_syncpt_incr_max(struct host1x_syncpt *sp, u32 incrs) +{ + return (u32)atomic_add_return(incrs, &sp->max_val); +} +EXPORT_SYMBOL(host1x_syncpt_incr_max); + + /* + * Write cached syncpoint and waitbase values to hardware. + */ +void host1x_syncpt_restore(struct host1x *host) +{ + struct host1x_syncpt *sp_base = host->syncpt; + u32 i; + + for (i = 0; i < host1x_syncpt_nb_pts(host); i++) + host1x_hw_syncpt_restore(host, sp_base + i); + for (i = 0; i < host1x_syncpt_nb_bases(host); i++) + host1x_hw_syncpt_restore_wait_base(host, sp_base + i); + wmb(); +} + +/* + * Update the cached syncpoint and waitbase values by reading them + * from the registers. + */ +void host1x_syncpt_save(struct host1x *host) +{ + struct host1x_syncpt *sp_base = host->syncpt; + u32 i; + + for (i = 0; i < host1x_syncpt_nb_pts(host); i++) { + if (host1x_syncpt_client_managed(sp_base + i)) + host1x_hw_syncpt_load(host, sp_base + i); + else + WARN_ON(!host1x_syncpt_idle(sp_base + i)); + } + + for (i = 0; i < host1x_syncpt_nb_bases(host); i++) + host1x_hw_syncpt_load_wait_base(host, sp_base + i); +} + +/* + * Updates the cached syncpoint value by reading a new value from the hardware + * register + */ +u32 host1x_syncpt_load(struct host1x_syncpt *sp) +{ + u32 val; + val = host1x_hw_syncpt_load(sp->host, sp); + trace_host1x_syncpt_load_min(sp->id, val); + + return val; +} + +/* + * Get the current syncpoint base + */ +u32 host1x_syncpt_load_wait_base(struct host1x_syncpt *sp) +{ + u32 val; + host1x_hw_syncpt_load_wait_base(sp->host, sp); + val = sp->base_val; + return val; +} + +/* + * Increment syncpoint value from cpu, updating cache + */ +int host1x_syncpt_incr(struct host1x_syncpt *sp) +{ + return host1x_hw_syncpt_cpu_incr(sp->host, sp); +} +EXPORT_SYMBOL(host1x_syncpt_incr); + +/* + * Updated sync point form hardware, and returns true if syncpoint is expired, + * false if we may need to wait + */ +static bool syncpt_load_min_is_expired(struct host1x_syncpt *sp, u32 thresh) +{ + host1x_hw_syncpt_load(sp->host, sp); + return host1x_syncpt_is_expired(sp, thresh); +} + +/* + * Main entrypoint for syncpoint value waits. + */ +int host1x_syncpt_wait(struct host1x_syncpt *sp, u32 thresh, long timeout, + u32 *value) +{ + DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); + void *ref; + struct host1x_waitlist *waiter; + int err = 0, check_count = 0; + u32 val; + + if (value) + *value = 0; + + /* first check cache */ + if (host1x_syncpt_is_expired(sp, thresh)) { + if (value) + *value = host1x_syncpt_load(sp); + return 0; + } + + /* try to read from register */ + val = host1x_hw_syncpt_load(sp->host, sp); + if (host1x_syncpt_is_expired(sp, thresh)) { + if (value) + *value = val; + goto done; + } + + if (!timeout) { + err = -EAGAIN; + goto done; + } + + /* allocate a waiter */ + waiter = kzalloc(sizeof(*waiter), GFP_KERNEL); + if (!waiter) { + err = -ENOMEM; + goto done; + } + + /* schedule a wakeup when the syncpoint value is reached */ + err = host1x_intr_add_action(sp->host, sp->id, thresh, + HOST1X_INTR_ACTION_WAKEUP_INTERRUPTIBLE, + &wq, waiter, &ref); + if (err) + goto done; + + err = -EAGAIN; + /* Caller-specified timeout may be impractically low */ + if (timeout < 0) + timeout = LONG_MAX; + + /* wait for the syncpoint, or timeout, or signal */ + while (timeout) { + long check = min_t(long, SYNCPT_CHECK_PERIOD, timeout); + int remain = wait_event_interruptible_timeout(wq, + syncpt_load_min_is_expired(sp, thresh), + check); + if (remain > 0 || host1x_syncpt_is_expired(sp, thresh)) { + if (value) + *value = host1x_syncpt_load(sp); + err = 0; + break; + } + if (remain < 0) { + err = remain; + break; + } + timeout -= check; + if (timeout && check_count <= MAX_STUCK_CHECK_COUNT) { + dev_warn(sp->host->dev, + "%s: syncpoint id %d (%s) stuck waiting %d, timeout=%ld\n", + current->comm, sp->id, sp->name, + thresh, timeout); + + host1x_debug_dump_syncpts(sp->host); + if (check_count == MAX_STUCK_CHECK_COUNT) + host1x_debug_dump(sp->host); + check_count++; + } + } + host1x_intr_put_ref(sp->host, sp->id, ref); + +done: + return err; +} +EXPORT_SYMBOL(host1x_syncpt_wait); + +/* + * Returns true if syncpoint is expired, false if we may need to wait + */ +bool host1x_syncpt_is_expired(struct host1x_syncpt *sp, u32 thresh) +{ + u32 current_val; + u32 future_val; + smp_rmb(); + current_val = (u32)atomic_read(&sp->min_val); + future_val = (u32)atomic_read(&sp->max_val); + + /* Note the use of unsigned arithmetic here (mod 1<<32). + * + * c = current_val = min_val = the current value of the syncpoint. + * t = thresh = the value we are checking + * f = future_val = max_val = the value c will reach when all + * outstanding increments have completed. + * + * Note that c always chases f until it reaches f. + * + * Dtf = (f - t) + * Dtc = (c - t) + * + * Consider all cases: + * + * A) .....c..t..f..... Dtf < Dtc need to wait + * B) .....c.....f..t.. Dtf > Dtc expired + * C) ..t..c.....f..... Dtf > Dtc expired (Dct very large) + * + * Any case where f==c: always expired (for any t). Dtf == Dcf + * Any case where t==c: always expired (for any f). Dtf >= Dtc (because Dtc==0) + * Any case where t==f!=c: always wait. Dtf < Dtc (because Dtf==0, + * Dtc!=0) + * + * Other cases: + * + * A) .....t..f..c..... Dtf < Dtc need to wait + * A) .....f..c..t..... Dtf < Dtc need to wait + * A) .....f..t..c..... Dtf > Dtc expired + * + * So: + * Dtf >= Dtc implies EXPIRED (return true) + * Dtf < Dtc implies WAIT (return false) + * + * Note: If t is expired then we *cannot* wait on it. We would wait + * forever (hang the system). + * + * Note: do NOT get clever and remove the -thresh from both sides. It + * is NOT the same. + * + * If future valueis zero, we have a client managed sync point. In that + * case we do a direct comparison. + */ + if (!host1x_syncpt_client_managed(sp)) + return future_val - thresh >= current_val - thresh; + else + return (s32)(current_val - thresh) >= 0; +} + +/* remove a wait pointed to by patch_addr */ +int host1x_syncpt_patch_wait(struct host1x_syncpt *sp, void *patch_addr) +{ + return host1x_hw_syncpt_patch_wait(sp->host, sp, patch_addr); +} + +int host1x_syncpt_init(struct host1x *host) +{ + struct host1x_syncpt_base *bases; + struct host1x_syncpt *syncpt; + int i; + + syncpt = devm_kzalloc(host->dev, sizeof(*syncpt) * host->info->nb_pts, + GFP_KERNEL); + if (!syncpt) + return -ENOMEM; + + bases = devm_kzalloc(host->dev, sizeof(*bases) * host->info->nb_bases, + GFP_KERNEL); + if (!bases) + return -ENOMEM; + + for (i = 0; i < host->info->nb_pts; i++) { + syncpt[i].id = i; + syncpt[i].host = host; + } + + for (i = 0; i < host->info->nb_bases; i++) + bases[i].id = i; + + host->syncpt = syncpt; + host->bases = bases; + + host1x_syncpt_restore(host); + + /* Allocate sync point to use for clearing waits for expired fences */ + host->nop_sp = host1x_syncpt_alloc(host, NULL, 0); + if (!host->nop_sp) + return -ENOMEM; + + return 0; +} + +struct host1x_syncpt *host1x_syncpt_request(struct device *dev, + unsigned long flags) +{ + struct host1x *host = dev_get_drvdata(dev->parent); + return host1x_syncpt_alloc(host, dev, flags); +} +EXPORT_SYMBOL(host1x_syncpt_request); + +void host1x_syncpt_free(struct host1x_syncpt *sp) +{ + if (!sp) + return; + + host1x_syncpt_base_free(sp->base); + kfree(sp->name); + sp->base = NULL; + sp->dev = NULL; + sp->name = NULL; + sp->client_managed = false; +} +EXPORT_SYMBOL(host1x_syncpt_free); + +void host1x_syncpt_deinit(struct host1x *host) +{ + int i; + struct host1x_syncpt *sp = host->syncpt; + for (i = 0; i < host->info->nb_pts; i++, sp++) + kfree(sp->name); +} + +/* + * Read max. It indicates how many operations there are in queue, either in + * channel or in a software thread. + * */ +u32 host1x_syncpt_read_max(struct host1x_syncpt *sp) +{ + smp_rmb(); + return (u32)atomic_read(&sp->max_val); +} +EXPORT_SYMBOL(host1x_syncpt_read_max); + +/* + * Read min, which is a shadow of the current sync point value in hardware. + */ +u32 host1x_syncpt_read_min(struct host1x_syncpt *sp) +{ + smp_rmb(); + return (u32)atomic_read(&sp->min_val); +} +EXPORT_SYMBOL(host1x_syncpt_read_min); + +u32 host1x_syncpt_read(struct host1x_syncpt *sp) +{ + return host1x_syncpt_load(sp); +} +EXPORT_SYMBOL(host1x_syncpt_read); + +int host1x_syncpt_nb_pts(struct host1x *host) +{ + return host->info->nb_pts; +} + +int host1x_syncpt_nb_bases(struct host1x *host) +{ + return host->info->nb_bases; +} + +int host1x_syncpt_nb_mlocks(struct host1x *host) +{ + return host->info->nb_mlocks; +} + +struct host1x_syncpt *host1x_syncpt_get(struct host1x *host, u32 id) +{ + if (host->info->nb_pts < id) + return NULL; + return host->syncpt + id; +} +EXPORT_SYMBOL(host1x_syncpt_get); + +struct host1x_syncpt_base *host1x_syncpt_get_base(struct host1x_syncpt *sp) +{ + return sp ? sp->base : NULL; +} +EXPORT_SYMBOL(host1x_syncpt_get_base); + +u32 host1x_syncpt_base_id(struct host1x_syncpt_base *base) +{ + return base->id; +} +EXPORT_SYMBOL(host1x_syncpt_base_id); |