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|
/*
* Copyright 2009 Jerome Glisse.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
* USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
*/
/*
* Authors:
* Jerome Glisse <glisse@freedesktop.org>
* Dave Airlie
*/
#include <linux/seq_file.h>
#include <linux/atomic.h>
#include <linux/wait.h>
#include <linux/list.h>
#include <linux/kref.h>
#include <linux/slab.h>
#include "drmP.h"
#include "drm.h"
#include "radeon_reg.h"
#include "radeon.h"
#include "radeon_trace.h"
static void radeon_fence_write(struct radeon_device *rdev, u32 seq, int ring)
{
if (rdev->wb.enabled) {
*rdev->fence_drv[ring].cpu_addr = cpu_to_le32(seq);
} else {
WREG32(rdev->fence_drv[ring].scratch_reg, seq);
}
}
static u32 radeon_fence_read(struct radeon_device *rdev, int ring)
{
u32 seq = 0;
if (rdev->wb.enabled) {
seq = le32_to_cpu(*rdev->fence_drv[ring].cpu_addr);
} else {
seq = RREG32(rdev->fence_drv[ring].scratch_reg);
}
return seq;
}
int radeon_fence_emit(struct radeon_device *rdev,
struct radeon_fence **fence,
int ring)
{
/* we are protected by the ring emission mutex */
*fence = kmalloc(sizeof(struct radeon_fence), GFP_KERNEL);
if ((*fence) == NULL) {
return -ENOMEM;
}
kref_init(&((*fence)->kref));
(*fence)->rdev = rdev;
(*fence)->seq = ++rdev->fence_drv[ring].sync_seq[ring];
(*fence)->ring = ring;
radeon_fence_ring_emit(rdev, ring, *fence);
trace_radeon_fence_emit(rdev->ddev, (*fence)->seq);
return 0;
}
void radeon_fence_process(struct radeon_device *rdev, int ring)
{
uint64_t seq, last_seq;
unsigned count_loop = 0;
bool wake = false;
/* Note there is a scenario here for an infinite loop but it's
* very unlikely to happen. For it to happen, the current polling
* process need to be interrupted by another process and another
* process needs to update the last_seq btw the atomic read and
* xchg of the current process.
*
* More over for this to go in infinite loop there need to be
* continuously new fence signaled ie radeon_fence_read needs
* to return a different value each time for both the currently
* polling process and the other process that xchg the last_seq
* btw atomic read and xchg of the current process. And the
* value the other process set as last seq must be higher than
* the seq value we just read. Which means that current process
* need to be interrupted after radeon_fence_read and before
* atomic xchg.
*
* To be even more safe we count the number of time we loop and
* we bail after 10 loop just accepting the fact that we might
* have temporarly set the last_seq not to the true real last
* seq but to an older one.
*/
last_seq = atomic64_read(&rdev->fence_drv[ring].last_seq);
do {
seq = radeon_fence_read(rdev, ring);
seq |= last_seq & 0xffffffff00000000LL;
if (seq < last_seq) {
seq += 0x100000000LL;
}
if (seq == last_seq) {
break;
}
/* If we loop over we don't want to return without
* checking if a fence is signaled as it means that the
* seq we just read is different from the previous on.
*/
wake = true;
last_seq = seq;
if ((count_loop++) > 10) {
/* We looped over too many time leave with the
* fact that we might have set an older fence
* seq then the current real last seq as signaled
* by the hw.
*/
break;
}
} while (atomic64_xchg(&rdev->fence_drv[ring].last_seq, seq) > seq);
if (wake) {
rdev->fence_drv[ring].last_activity = jiffies;
wake_up_all(&rdev->fence_queue);
}
}
static void radeon_fence_destroy(struct kref *kref)
{
struct radeon_fence *fence;
fence = container_of(kref, struct radeon_fence, kref);
kfree(fence);
}
static bool radeon_fence_seq_signaled(struct radeon_device *rdev,
u64 seq, unsigned ring)
{
if (atomic64_read(&rdev->fence_drv[ring].last_seq) >= seq) {
return true;
}
/* poll new last sequence at least once */
radeon_fence_process(rdev, ring);
if (atomic64_read(&rdev->fence_drv[ring].last_seq) >= seq) {
return true;
}
return false;
}
bool radeon_fence_signaled(struct radeon_fence *fence)
{
if (!fence) {
return true;
}
if (fence->seq == RADEON_FENCE_SIGNALED_SEQ) {
return true;
}
if (radeon_fence_seq_signaled(fence->rdev, fence->seq, fence->ring)) {
fence->seq = RADEON_FENCE_SIGNALED_SEQ;
return true;
}
return false;
}
static int radeon_fence_wait_seq(struct radeon_device *rdev, u64 target_seq,
unsigned ring, bool intr, bool lock_ring)
{
unsigned long timeout, last_activity;
uint64_t seq;
unsigned i;
bool signaled;
int r;
while (target_seq > atomic64_read(&rdev->fence_drv[ring].last_seq)) {
if (!rdev->ring[ring].ready) {
return -EBUSY;
}
timeout = jiffies - RADEON_FENCE_JIFFIES_TIMEOUT;
if (time_after(rdev->fence_drv[ring].last_activity, timeout)) {
/* the normal case, timeout is somewhere before last_activity */
timeout = rdev->fence_drv[ring].last_activity - timeout;
} else {
/* either jiffies wrapped around, or no fence was signaled in the last 500ms
* anyway we will just wait for the minimum amount and then check for a lockup
*/
timeout = 1;
}
seq = atomic64_read(&rdev->fence_drv[ring].last_seq);
/* Save current last activity valuee, used to check for GPU lockups */
last_activity = rdev->fence_drv[ring].last_activity;
trace_radeon_fence_wait_begin(rdev->ddev, seq);
radeon_irq_kms_sw_irq_get(rdev, ring);
if (intr) {
r = wait_event_interruptible_timeout(rdev->fence_queue,
(signaled = radeon_fence_seq_signaled(rdev, target_seq, ring)),
timeout);
} else {
r = wait_event_timeout(rdev->fence_queue,
(signaled = radeon_fence_seq_signaled(rdev, target_seq, ring)),
timeout);
}
radeon_irq_kms_sw_irq_put(rdev, ring);
if (unlikely(r < 0)) {
return r;
}
trace_radeon_fence_wait_end(rdev->ddev, seq);
if (unlikely(!signaled)) {
/* we were interrupted for some reason and fence
* isn't signaled yet, resume waiting */
if (r) {
continue;
}
/* check if sequence value has changed since last_activity */
if (seq != atomic64_read(&rdev->fence_drv[ring].last_seq)) {
continue;
}
if (lock_ring) {
mutex_lock(&rdev->ring_lock);
}
/* test if somebody else has already decided that this is a lockup */
if (last_activity != rdev->fence_drv[ring].last_activity) {
if (lock_ring) {
mutex_unlock(&rdev->ring_lock);
}
continue;
}
if (radeon_ring_is_lockup(rdev, ring, &rdev->ring[ring])) {
/* good news we believe it's a lockup */
dev_warn(rdev->dev, "GPU lockup (waiting for 0x%016llx last fence id 0x%016llx)\n",
target_seq, seq);
/* change last activity so nobody else think there is a lockup */
for (i = 0; i < RADEON_NUM_RINGS; ++i) {
rdev->fence_drv[i].last_activity = jiffies;
}
/* mark the ring as not ready any more */
rdev->ring[ring].ready = false;
if (lock_ring) {
mutex_unlock(&rdev->ring_lock);
}
return -EDEADLK;
}
if (lock_ring) {
mutex_unlock(&rdev->ring_lock);
}
}
}
return 0;
}
int radeon_fence_wait(struct radeon_fence *fence, bool intr)
{
int r;
if (fence == NULL) {
WARN(1, "Querying an invalid fence : %p !\n", fence);
return -EINVAL;
}
r = radeon_fence_wait_seq(fence->rdev, fence->seq,
fence->ring, intr, true);
if (r) {
return r;
}
fence->seq = RADEON_FENCE_SIGNALED_SEQ;
return 0;
}
bool radeon_fence_any_seq_signaled(struct radeon_device *rdev, u64 *seq)
{
unsigned i;
for (i = 0; i < RADEON_NUM_RINGS; ++i) {
if (seq[i] && radeon_fence_seq_signaled(rdev, seq[i], i)) {
return true;
}
}
return false;
}
static int radeon_fence_wait_any_seq(struct radeon_device *rdev,
u64 *target_seq, bool intr)
{
unsigned long timeout, last_activity, tmp;
unsigned i, ring = RADEON_NUM_RINGS;
bool signaled;
int r;
for (i = 0, last_activity = 0; i < RADEON_NUM_RINGS; ++i) {
if (!target_seq[i]) {
continue;
}
/* use the most recent one as indicator */
if (time_after(rdev->fence_drv[i].last_activity, last_activity)) {
last_activity = rdev->fence_drv[i].last_activity;
}
/* For lockup detection just pick the lowest ring we are
* actively waiting for
*/
if (i < ring) {
ring = i;
}
}
/* nothing to wait for ? */
if (ring == RADEON_NUM_RINGS) {
return 0;
}
while (!radeon_fence_any_seq_signaled(rdev, target_seq)) {
timeout = jiffies - RADEON_FENCE_JIFFIES_TIMEOUT;
if (time_after(last_activity, timeout)) {
/* the normal case, timeout is somewhere before last_activity */
timeout = last_activity - timeout;
} else {
/* either jiffies wrapped around, or no fence was signaled in the last 500ms
* anyway we will just wait for the minimum amount and then check for a lockup
*/
timeout = 1;
}
trace_radeon_fence_wait_begin(rdev->ddev, target_seq[ring]);
for (i = 0; i < RADEON_NUM_RINGS; ++i) {
if (target_seq[i]) {
radeon_irq_kms_sw_irq_get(rdev, i);
}
}
if (intr) {
r = wait_event_interruptible_timeout(rdev->fence_queue,
(signaled = radeon_fence_any_seq_signaled(rdev, target_seq)),
timeout);
} else {
r = wait_event_timeout(rdev->fence_queue,
(signaled = radeon_fence_any_seq_signaled(rdev, target_seq)),
timeout);
}
for (i = 0; i < RADEON_NUM_RINGS; ++i) {
if (target_seq[i]) {
radeon_irq_kms_sw_irq_put(rdev, i);
}
}
if (unlikely(r < 0)) {
return r;
}
trace_radeon_fence_wait_end(rdev->ddev, target_seq[ring]);
if (unlikely(!signaled)) {
/* we were interrupted for some reason and fence
* isn't signaled yet, resume waiting */
if (r) {
continue;
}
mutex_lock(&rdev->ring_lock);
for (i = 0, tmp = 0; i < RADEON_NUM_RINGS; ++i) {
if (time_after(rdev->fence_drv[i].last_activity, tmp)) {
tmp = rdev->fence_drv[i].last_activity;
}
}
/* test if somebody else has already decided that this is a lockup */
if (last_activity != tmp) {
last_activity = tmp;
mutex_unlock(&rdev->ring_lock);
continue;
}
if (radeon_ring_is_lockup(rdev, ring, &rdev->ring[ring])) {
/* good news we believe it's a lockup */
dev_warn(rdev->dev, "GPU lockup (waiting for 0x%016llx)\n",
target_seq[ring]);
/* change last activity so nobody else think there is a lockup */
for (i = 0; i < RADEON_NUM_RINGS; ++i) {
rdev->fence_drv[i].last_activity = jiffies;
}
/* mark the ring as not ready any more */
rdev->ring[ring].ready = false;
mutex_unlock(&rdev->ring_lock);
return -EDEADLK;
}
mutex_unlock(&rdev->ring_lock);
}
}
return 0;
}
int radeon_fence_wait_any(struct radeon_device *rdev,
struct radeon_fence **fences,
bool intr)
{
uint64_t seq[RADEON_NUM_RINGS];
unsigned i;
int r;
for (i = 0; i < RADEON_NUM_RINGS; ++i) {
seq[i] = 0;
if (!fences[i]) {
continue;
}
if (fences[i]->seq == RADEON_FENCE_SIGNALED_SEQ) {
/* something was allready signaled */
return 0;
}
seq[i] = fences[i]->seq;
}
r = radeon_fence_wait_any_seq(rdev, seq, intr);
if (r) {
return r;
}
return 0;
}
/* caller must hold ring lock */
int radeon_fence_wait_next_locked(struct radeon_device *rdev, int ring)
{
uint64_t seq;
seq = atomic64_read(&rdev->fence_drv[ring].last_seq) + 1ULL;
if (seq >= rdev->fence_drv[ring].sync_seq[ring]) {
/* nothing to wait for, last_seq is
already the last emited fence */
return -ENOENT;
}
return radeon_fence_wait_seq(rdev, seq, ring, false, false);
}
/* caller must hold ring lock */
void radeon_fence_wait_empty_locked(struct radeon_device *rdev, int ring)
{
uint64_t seq = rdev->fence_drv[ring].sync_seq[ring];
while(1) {
int r;
r = radeon_fence_wait_seq(rdev, seq, ring, false, false);
if (r == -EDEADLK) {
mutex_unlock(&rdev->ring_lock);
r = radeon_gpu_reset(rdev);
mutex_lock(&rdev->ring_lock);
if (!r)
continue;
}
if (r) {
dev_err(rdev->dev, "error waiting for ring to become"
" idle (%d)\n", r);
}
return;
}
}
struct radeon_fence *radeon_fence_ref(struct radeon_fence *fence)
{
kref_get(&fence->kref);
return fence;
}
void radeon_fence_unref(struct radeon_fence **fence)
{
struct radeon_fence *tmp = *fence;
*fence = NULL;
if (tmp) {
kref_put(&tmp->kref, radeon_fence_destroy);
}
}
unsigned radeon_fence_count_emitted(struct radeon_device *rdev, int ring)
{
uint64_t emitted;
/* We are not protected by ring lock when reading the last sequence
* but it's ok to report slightly wrong fence count here.
*/
radeon_fence_process(rdev, ring);
emitted = rdev->fence_drv[ring].sync_seq[ring]
- atomic64_read(&rdev->fence_drv[ring].last_seq);
/* to avoid 32bits warp around */
if (emitted > 0x10000000) {
emitted = 0x10000000;
}
return (unsigned)emitted;
}
bool radeon_fence_need_sync(struct radeon_fence *fence, int dst_ring)
{
struct radeon_fence_driver *fdrv;
if (!fence) {
return false;
}
if (fence->ring == dst_ring) {
return false;
}
/* we are protected by the ring mutex */
fdrv = &fence->rdev->fence_drv[dst_ring];
if (fence->seq <= fdrv->sync_seq[fence->ring]) {
return false;
}
return true;
}
void radeon_fence_note_sync(struct radeon_fence *fence, int dst_ring)
{
struct radeon_fence_driver *dst, *src;
unsigned i;
if (!fence) {
return;
}
if (fence->ring == dst_ring) {
return;
}
/* we are protected by the ring mutex */
src = &fence->rdev->fence_drv[fence->ring];
dst = &fence->rdev->fence_drv[dst_ring];
for (i = 0; i < RADEON_NUM_RINGS; ++i) {
if (i == dst_ring) {
continue;
}
dst->sync_seq[i] = max(dst->sync_seq[i], src->sync_seq[i]);
}
}
int radeon_fence_driver_start_ring(struct radeon_device *rdev, int ring)
{
uint64_t index;
int r;
radeon_scratch_free(rdev, rdev->fence_drv[ring].scratch_reg);
if (rdev->wb.use_event) {
rdev->fence_drv[ring].scratch_reg = 0;
index = R600_WB_EVENT_OFFSET + ring * 4;
} else {
r = radeon_scratch_get(rdev, &rdev->fence_drv[ring].scratch_reg);
if (r) {
dev_err(rdev->dev, "fence failed to get scratch register\n");
return r;
}
index = RADEON_WB_SCRATCH_OFFSET +
rdev->fence_drv[ring].scratch_reg -
rdev->scratch.reg_base;
}
rdev->fence_drv[ring].cpu_addr = &rdev->wb.wb[index/4];
rdev->fence_drv[ring].gpu_addr = rdev->wb.gpu_addr + index;
radeon_fence_write(rdev, rdev->fence_drv[ring].sync_seq[ring], ring);
rdev->fence_drv[ring].initialized = true;
dev_info(rdev->dev, "fence driver on ring %d use gpu addr 0x%016llx and cpu addr 0x%p\n",
ring, rdev->fence_drv[ring].gpu_addr, rdev->fence_drv[ring].cpu_addr);
return 0;
}
static void radeon_fence_driver_init_ring(struct radeon_device *rdev, int ring)
{
int i;
rdev->fence_drv[ring].scratch_reg = -1;
rdev->fence_drv[ring].cpu_addr = NULL;
rdev->fence_drv[ring].gpu_addr = 0;
for (i = 0; i < RADEON_NUM_RINGS; ++i)
rdev->fence_drv[ring].sync_seq[i] = 0;
atomic64_set(&rdev->fence_drv[ring].last_seq, 0);
rdev->fence_drv[ring].last_activity = jiffies;
rdev->fence_drv[ring].initialized = false;
}
int radeon_fence_driver_init(struct radeon_device *rdev)
{
int ring;
init_waitqueue_head(&rdev->fence_queue);
for (ring = 0; ring < RADEON_NUM_RINGS; ring++) {
radeon_fence_driver_init_ring(rdev, ring);
}
if (radeon_debugfs_fence_init(rdev)) {
dev_err(rdev->dev, "fence debugfs file creation failed\n");
}
return 0;
}
void radeon_fence_driver_fini(struct radeon_device *rdev)
{
int ring;
mutex_lock(&rdev->ring_lock);
for (ring = 0; ring < RADEON_NUM_RINGS; ring++) {
if (!rdev->fence_drv[ring].initialized)
continue;
radeon_fence_wait_empty_locked(rdev, ring);
wake_up_all(&rdev->fence_queue);
radeon_scratch_free(rdev, rdev->fence_drv[ring].scratch_reg);
rdev->fence_drv[ring].initialized = false;
}
mutex_unlock(&rdev->ring_lock);
}
/*
* Fence debugfs
*/
#if defined(CONFIG_DEBUG_FS)
static int radeon_debugfs_fence_info(struct seq_file *m, void *data)
{
struct drm_info_node *node = (struct drm_info_node *)m->private;
struct drm_device *dev = node->minor->dev;
struct radeon_device *rdev = dev->dev_private;
int i, j;
for (i = 0; i < RADEON_NUM_RINGS; ++i) {
if (!rdev->fence_drv[i].initialized)
continue;
seq_printf(m, "--- ring %d ---\n", i);
seq_printf(m, "Last signaled fence 0x%016llx\n",
(unsigned long long)atomic64_read(&rdev->fence_drv[i].last_seq));
seq_printf(m, "Last emitted 0x%016llx\n",
rdev->fence_drv[i].sync_seq[i]);
for (j = 0; j < RADEON_NUM_RINGS; ++j) {
if (i != j && rdev->fence_drv[j].initialized)
seq_printf(m, "Last sync to ring %d 0x%016llx\n",
j, rdev->fence_drv[i].sync_seq[j]);
}
}
return 0;
}
static struct drm_info_list radeon_debugfs_fence_list[] = {
{"radeon_fence_info", &radeon_debugfs_fence_info, 0, NULL},
};
#endif
int radeon_debugfs_fence_init(struct radeon_device *rdev)
{
#if defined(CONFIG_DEBUG_FS)
return radeon_debugfs_add_files(rdev, radeon_debugfs_fence_list, 1);
#else
return 0;
#endif
}
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