![Arto Merilainen](/assets/img/avatar_default.png)
Currently syncpoints are not locked by mutex and this causes races if we are aggressively freeing and allocating syncpoints. This patch adds missing mutex protection to syncpoint structures. Signed-off-by: Arto Merilainen <amerilainen@nvidia.com> Reviewed-by: Shridhar Rasal <srasal@nvidia.com> Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com> [treding@nvidia.com: use better label names, don't reset local variable] Signed-off-by: Thierry Reding <treding@nvidia.com>
505 lines
11 KiB
C
505 lines
11 KiB
C
/*
|
|
* Tegra host1x Syncpoints
|
|
*
|
|
* Copyright (c) 2010-2015, 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;
|
|
|
|
mutex_lock(&host->syncpt_mutex);
|
|
|
|
for (i = 0; i < host->info->nb_pts && sp->name; i++, sp++)
|
|
;
|
|
|
|
if (i >= host->info->nb_pts)
|
|
goto unlock;
|
|
|
|
if (flags & HOST1X_SYNCPT_HAS_BASE) {
|
|
sp->base = host1x_syncpt_base_request(host);
|
|
if (!sp->base)
|
|
goto unlock;
|
|
}
|
|
|
|
name = kasprintf(GFP_KERNEL, "%02u-%s", sp->id,
|
|
dev ? dev_name(dev) : NULL);
|
|
if (!name)
|
|
goto free_base;
|
|
|
|
sp->dev = dev;
|
|
sp->name = name;
|
|
|
|
if (flags & HOST1X_SYNCPT_CLIENT_MANAGED)
|
|
sp->client_managed = true;
|
|
else
|
|
sp->client_managed = false;
|
|
|
|
mutex_unlock(&host->syncpt_mutex);
|
|
return sp;
|
|
|
|
free_base:
|
|
host1x_syncpt_base_free(sp->base);
|
|
sp->base = NULL;
|
|
unlock:
|
|
mutex_unlock(&host->syncpt_mutex);
|
|
return NULL;
|
|
}
|
|
|
|
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;
|
|
unsigned int 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;
|
|
unsigned int 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)
|
|
{
|
|
host1x_hw_syncpt_load_wait_base(sp->host, sp);
|
|
|
|
return sp->base_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;
|
|
|
|
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 %u (%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;
|
|
unsigned int i;
|
|
|
|
syncpt = devm_kcalloc(host->dev, host->info->nb_pts, sizeof(*syncpt),
|
|
GFP_KERNEL);
|
|
if (!syncpt)
|
|
return -ENOMEM;
|
|
|
|
bases = devm_kcalloc(host->dev, host->info->nb_bases, sizeof(*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;
|
|
|
|
mutex_init(&host->syncpt_mutex);
|
|
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;
|
|
|
|
mutex_lock(&sp->host->syncpt_mutex);
|
|
|
|
host1x_syncpt_base_free(sp->base);
|
|
kfree(sp->name);
|
|
sp->base = NULL;
|
|
sp->dev = NULL;
|
|
sp->name = NULL;
|
|
sp->client_managed = false;
|
|
|
|
mutex_unlock(&sp->host->syncpt_mutex);
|
|
}
|
|
EXPORT_SYMBOL(host1x_syncpt_free);
|
|
|
|
void host1x_syncpt_deinit(struct host1x *host)
|
|
{
|
|
struct host1x_syncpt *sp = host->syncpt;
|
|
unsigned int i;
|
|
|
|
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);
|
|
|
|
unsigned int host1x_syncpt_nb_pts(struct host1x *host)
|
|
{
|
|
return host->info->nb_pts;
|
|
}
|
|
|
|
unsigned int host1x_syncpt_nb_bases(struct host1x *host)
|
|
{
|
|
return host->info->nb_bases;
|
|
}
|
|
|
|
unsigned int host1x_syncpt_nb_mlocks(struct host1x *host)
|
|
{
|
|
return host->info->nb_mlocks;
|
|
}
|
|
|
|
struct host1x_syncpt *host1x_syncpt_get(struct host1x *host, unsigned int 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);
|