blob: c97423a766420cf23311e86d3ccdc848d4d41c3a [file] [log] [blame]
/*
* SPDX-License-Identifier: MIT
*
* Copyright © 2008-2018 Intel Corporation
*/
#include <linux/sched/mm.h>
#include <linux/stop_machine.h>
#include "display/intel_display_types.h"
#include "display/intel_overlay.h"
#include "gem/i915_gem_context.h"
#include "i915_drv.h"
#include "i915_gpu_error.h"
#include "i915_irq.h"
#include "intel_engine_pm.h"
#include "intel_gt.h"
#include "intel_gt_pm.h"
#include "intel_reset.h"
#include "uc/intel_guc.h"
#define RESET_MAX_RETRIES 3
/* XXX How to handle concurrent GGTT updates using tiling registers? */
#define RESET_UNDER_STOP_MACHINE 0
static void rmw_set_fw(struct intel_uncore *uncore, i915_reg_t reg, u32 set)
{
intel_uncore_rmw_fw(uncore, reg, 0, set);
}
static void rmw_clear_fw(struct intel_uncore *uncore, i915_reg_t reg, u32 clr)
{
intel_uncore_rmw_fw(uncore, reg, clr, 0);
}
static void engine_skip_context(struct i915_request *rq)
{
struct intel_engine_cs *engine = rq->engine;
struct i915_gem_context *hung_ctx = rq->gem_context;
if (!i915_request_is_active(rq))
return;
lockdep_assert_held(&engine->active.lock);
list_for_each_entry_continue(rq, &engine->active.requests, sched.link)
if (rq->gem_context == hung_ctx)
i915_request_skip(rq, -EIO);
}
static void client_mark_guilty(struct drm_i915_file_private *file_priv,
const struct i915_gem_context *ctx)
{
unsigned int score;
unsigned long prev_hang;
if (i915_gem_context_is_banned(ctx))
score = I915_CLIENT_SCORE_CONTEXT_BAN;
else
score = 0;
prev_hang = xchg(&file_priv->hang_timestamp, jiffies);
if (time_before(jiffies, prev_hang + I915_CLIENT_FAST_HANG_JIFFIES))
score += I915_CLIENT_SCORE_HANG_FAST;
if (score) {
atomic_add(score, &file_priv->ban_score);
DRM_DEBUG_DRIVER("client %s: gained %u ban score, now %u\n",
ctx->name, score,
atomic_read(&file_priv->ban_score));
}
}
static bool context_mark_guilty(struct i915_gem_context *ctx)
{
unsigned long prev_hang;
bool banned;
int i;
atomic_inc(&ctx->guilty_count);
/* Cool contexts are too cool to be banned! (Used for reset testing.) */
if (!i915_gem_context_is_bannable(ctx))
return false;
/* Record the timestamp for the last N hangs */
prev_hang = ctx->hang_timestamp[0];
for (i = 0; i < ARRAY_SIZE(ctx->hang_timestamp) - 1; i++)
ctx->hang_timestamp[i] = ctx->hang_timestamp[i + 1];
ctx->hang_timestamp[i] = jiffies;
/* If we have hung N+1 times in rapid succession, we ban the context! */
banned = !i915_gem_context_is_recoverable(ctx);
if (time_before(jiffies, prev_hang + CONTEXT_FAST_HANG_JIFFIES))
banned = true;
if (banned) {
DRM_DEBUG_DRIVER("context %s: guilty %d, banned\n",
ctx->name, atomic_read(&ctx->guilty_count));
i915_gem_context_set_banned(ctx);
}
if (!IS_ERR_OR_NULL(ctx->file_priv))
client_mark_guilty(ctx->file_priv, ctx);
return banned;
}
static void context_mark_innocent(struct i915_gem_context *ctx)
{
atomic_inc(&ctx->active_count);
}
void __i915_request_reset(struct i915_request *rq, bool guilty)
{
GEM_TRACE("%s rq=%llx:%lld, guilty? %s\n",
rq->engine->name,
rq->fence.context,
rq->fence.seqno,
yesno(guilty));
GEM_BUG_ON(i915_request_completed(rq));
if (guilty) {
i915_request_skip(rq, -EIO);
if (context_mark_guilty(rq->gem_context))
engine_skip_context(rq);
} else {
dma_fence_set_error(&rq->fence, -EAGAIN);
context_mark_innocent(rq->gem_context);
}
}
static bool i915_in_reset(struct pci_dev *pdev)
{
u8 gdrst;
pci_read_config_byte(pdev, I915_GDRST, &gdrst);
return gdrst & GRDOM_RESET_STATUS;
}
static int i915_do_reset(struct intel_gt *gt,
intel_engine_mask_t engine_mask,
unsigned int retry)
{
struct pci_dev *pdev = gt->i915->drm.pdev;
int err;
/* Assert reset for at least 20 usec, and wait for acknowledgement. */
pci_write_config_byte(pdev, I915_GDRST, GRDOM_RESET_ENABLE);
udelay(50);
err = wait_for_atomic(i915_in_reset(pdev), 50);
/* Clear the reset request. */
pci_write_config_byte(pdev, I915_GDRST, 0);
udelay(50);
if (!err)
err = wait_for_atomic(!i915_in_reset(pdev), 50);
return err;
}
static bool g4x_reset_complete(struct pci_dev *pdev)
{
u8 gdrst;
pci_read_config_byte(pdev, I915_GDRST, &gdrst);
return (gdrst & GRDOM_RESET_ENABLE) == 0;
}
static int g33_do_reset(struct intel_gt *gt,
intel_engine_mask_t engine_mask,
unsigned int retry)
{
struct pci_dev *pdev = gt->i915->drm.pdev;
pci_write_config_byte(pdev, I915_GDRST, GRDOM_RESET_ENABLE);
return wait_for_atomic(g4x_reset_complete(pdev), 50);
}
static int g4x_do_reset(struct intel_gt *gt,
intel_engine_mask_t engine_mask,
unsigned int retry)
{
struct pci_dev *pdev = gt->i915->drm.pdev;
struct intel_uncore *uncore = gt->uncore;
int ret;
/* WaVcpClkGateDisableForMediaReset:ctg,elk */
rmw_set_fw(uncore, VDECCLK_GATE_D, VCP_UNIT_CLOCK_GATE_DISABLE);
intel_uncore_posting_read_fw(uncore, VDECCLK_GATE_D);
pci_write_config_byte(pdev, I915_GDRST,
GRDOM_MEDIA | GRDOM_RESET_ENABLE);
ret = wait_for_atomic(g4x_reset_complete(pdev), 50);
if (ret) {
DRM_DEBUG_DRIVER("Wait for media reset failed\n");
goto out;
}
pci_write_config_byte(pdev, I915_GDRST,
GRDOM_RENDER | GRDOM_RESET_ENABLE);
ret = wait_for_atomic(g4x_reset_complete(pdev), 50);
if (ret) {
DRM_DEBUG_DRIVER("Wait for render reset failed\n");
goto out;
}
out:
pci_write_config_byte(pdev, I915_GDRST, 0);
rmw_clear_fw(uncore, VDECCLK_GATE_D, VCP_UNIT_CLOCK_GATE_DISABLE);
intel_uncore_posting_read_fw(uncore, VDECCLK_GATE_D);
return ret;
}
static int ironlake_do_reset(struct intel_gt *gt,
intel_engine_mask_t engine_mask,
unsigned int retry)
{
struct intel_uncore *uncore = gt->uncore;
int ret;
intel_uncore_write_fw(uncore, ILK_GDSR,
ILK_GRDOM_RENDER | ILK_GRDOM_RESET_ENABLE);
ret = __intel_wait_for_register_fw(uncore, ILK_GDSR,
ILK_GRDOM_RESET_ENABLE, 0,
5000, 0,
NULL);
if (ret) {
DRM_DEBUG_DRIVER("Wait for render reset failed\n");
goto out;
}
intel_uncore_write_fw(uncore, ILK_GDSR,
ILK_GRDOM_MEDIA | ILK_GRDOM_RESET_ENABLE);
ret = __intel_wait_for_register_fw(uncore, ILK_GDSR,
ILK_GRDOM_RESET_ENABLE, 0,
5000, 0,
NULL);
if (ret) {
DRM_DEBUG_DRIVER("Wait for media reset failed\n");
goto out;
}
out:
intel_uncore_write_fw(uncore, ILK_GDSR, 0);
intel_uncore_posting_read_fw(uncore, ILK_GDSR);
return ret;
}
/* Reset the hardware domains (GENX_GRDOM_*) specified by mask */
static int gen6_hw_domain_reset(struct intel_gt *gt, u32 hw_domain_mask)
{
struct intel_uncore *uncore = gt->uncore;
int err;
/*
* GEN6_GDRST is not in the gt power well, no need to check
* for fifo space for the write or forcewake the chip for
* the read
*/
intel_uncore_write_fw(uncore, GEN6_GDRST, hw_domain_mask);
/* Wait for the device to ack the reset requests */
err = __intel_wait_for_register_fw(uncore,
GEN6_GDRST, hw_domain_mask, 0,
500, 0,
NULL);
if (err)
DRM_DEBUG_DRIVER("Wait for 0x%08x engines reset failed\n",
hw_domain_mask);
return err;
}
static int gen6_reset_engines(struct intel_gt *gt,
intel_engine_mask_t engine_mask,
unsigned int retry)
{
static const u32 hw_engine_mask[] = {
[RCS0] = GEN6_GRDOM_RENDER,
[BCS0] = GEN6_GRDOM_BLT,
[VCS0] = GEN6_GRDOM_MEDIA,
[VCS1] = GEN8_GRDOM_MEDIA2,
[VECS0] = GEN6_GRDOM_VECS,
};
struct intel_engine_cs *engine;
u32 hw_mask;
if (engine_mask == ALL_ENGINES) {
hw_mask = GEN6_GRDOM_FULL;
} else {
intel_engine_mask_t tmp;
hw_mask = 0;
for_each_engine_masked(engine, gt, engine_mask, tmp) {
GEM_BUG_ON(engine->id >= ARRAY_SIZE(hw_engine_mask));
hw_mask |= hw_engine_mask[engine->id];
}
}
return gen6_hw_domain_reset(gt, hw_mask);
}
static int gen11_lock_sfc(struct intel_engine_cs *engine, u32 *hw_mask)
{
struct intel_uncore *uncore = engine->uncore;
u8 vdbox_sfc_access = RUNTIME_INFO(engine->i915)->vdbox_sfc_access;
i915_reg_t sfc_forced_lock, sfc_forced_lock_ack;
u32 sfc_forced_lock_bit, sfc_forced_lock_ack_bit;
i915_reg_t sfc_usage;
u32 sfc_usage_bit;
u32 sfc_reset_bit;
int ret;
switch (engine->class) {
case VIDEO_DECODE_CLASS:
if ((BIT(engine->instance) & vdbox_sfc_access) == 0)
return 0;
sfc_forced_lock = GEN11_VCS_SFC_FORCED_LOCK(engine);
sfc_forced_lock_bit = GEN11_VCS_SFC_FORCED_LOCK_BIT;
sfc_forced_lock_ack = GEN11_VCS_SFC_LOCK_STATUS(engine);
sfc_forced_lock_ack_bit = GEN11_VCS_SFC_LOCK_ACK_BIT;
sfc_usage = GEN11_VCS_SFC_LOCK_STATUS(engine);
sfc_usage_bit = GEN11_VCS_SFC_USAGE_BIT;
sfc_reset_bit = GEN11_VCS_SFC_RESET_BIT(engine->instance);
break;
case VIDEO_ENHANCEMENT_CLASS:
sfc_forced_lock = GEN11_VECS_SFC_FORCED_LOCK(engine);
sfc_forced_lock_bit = GEN11_VECS_SFC_FORCED_LOCK_BIT;
sfc_forced_lock_ack = GEN11_VECS_SFC_LOCK_ACK(engine);
sfc_forced_lock_ack_bit = GEN11_VECS_SFC_LOCK_ACK_BIT;
sfc_usage = GEN11_VECS_SFC_USAGE(engine);
sfc_usage_bit = GEN11_VECS_SFC_USAGE_BIT;
sfc_reset_bit = GEN11_VECS_SFC_RESET_BIT(engine->instance);
break;
default:
return 0;
}
/*
* If the engine is using a SFC, tell the engine that a software reset
* is going to happen. The engine will then try to force lock the SFC.
* If SFC ends up being locked to the engine we want to reset, we have
* to reset it as well (we will unlock it once the reset sequence is
* completed).
*/
if (!(intel_uncore_read_fw(uncore, sfc_usage) & sfc_usage_bit))
return 0;
rmw_set_fw(uncore, sfc_forced_lock, sfc_forced_lock_bit);
ret = __intel_wait_for_register_fw(uncore,
sfc_forced_lock_ack,
sfc_forced_lock_ack_bit,
sfc_forced_lock_ack_bit,
1000, 0, NULL);
/* Was the SFC released while we were trying to lock it? */
if (!(intel_uncore_read_fw(uncore, sfc_usage) & sfc_usage_bit))
return 0;
if (ret) {
DRM_DEBUG_DRIVER("Wait for SFC forced lock ack failed\n");
return ret;
}
*hw_mask |= sfc_reset_bit;
return 0;
}
static void gen11_unlock_sfc(struct intel_engine_cs *engine)
{
struct intel_uncore *uncore = engine->uncore;
u8 vdbox_sfc_access = RUNTIME_INFO(engine->i915)->vdbox_sfc_access;
i915_reg_t sfc_forced_lock;
u32 sfc_forced_lock_bit;
switch (engine->class) {
case VIDEO_DECODE_CLASS:
if ((BIT(engine->instance) & vdbox_sfc_access) == 0)
return;
sfc_forced_lock = GEN11_VCS_SFC_FORCED_LOCK(engine);
sfc_forced_lock_bit = GEN11_VCS_SFC_FORCED_LOCK_BIT;
break;
case VIDEO_ENHANCEMENT_CLASS:
sfc_forced_lock = GEN11_VECS_SFC_FORCED_LOCK(engine);
sfc_forced_lock_bit = GEN11_VECS_SFC_FORCED_LOCK_BIT;
break;
default:
return;
}
rmw_clear_fw(uncore, sfc_forced_lock, sfc_forced_lock_bit);
}
static int gen11_reset_engines(struct intel_gt *gt,
intel_engine_mask_t engine_mask,
unsigned int retry)
{
static const u32 hw_engine_mask[] = {
[RCS0] = GEN11_GRDOM_RENDER,
[BCS0] = GEN11_GRDOM_BLT,
[VCS0] = GEN11_GRDOM_MEDIA,
[VCS1] = GEN11_GRDOM_MEDIA2,
[VCS2] = GEN11_GRDOM_MEDIA3,
[VCS3] = GEN11_GRDOM_MEDIA4,
[VECS0] = GEN11_GRDOM_VECS,
[VECS1] = GEN11_GRDOM_VECS2,
};
struct intel_engine_cs *engine;
intel_engine_mask_t tmp;
u32 hw_mask;
int ret;
if (engine_mask == ALL_ENGINES) {
hw_mask = GEN11_GRDOM_FULL;
} else {
hw_mask = 0;
for_each_engine_masked(engine, gt, engine_mask, tmp) {
GEM_BUG_ON(engine->id >= ARRAY_SIZE(hw_engine_mask));
hw_mask |= hw_engine_mask[engine->id];
ret = gen11_lock_sfc(engine, &hw_mask);
if (ret)
goto sfc_unlock;
}
}
ret = gen6_hw_domain_reset(gt, hw_mask);
sfc_unlock:
/*
* We unlock the SFC based on the lock status and not the result of
* gen11_lock_sfc to make sure that we clean properly if something
* wrong happened during the lock (e.g. lock acquired after timeout
* expiration).
*/
if (engine_mask != ALL_ENGINES)
for_each_engine_masked(engine, gt, engine_mask, tmp)
gen11_unlock_sfc(engine);
return ret;
}
static int gen8_engine_reset_prepare(struct intel_engine_cs *engine)
{
struct intel_uncore *uncore = engine->uncore;
const i915_reg_t reg = RING_RESET_CTL(engine->mmio_base);
u32 request, mask, ack;
int ret;
ack = intel_uncore_read_fw(uncore, reg);
if (ack & RESET_CTL_CAT_ERROR) {
/*
* For catastrophic errors, ready-for-reset sequence
* needs to be bypassed: HAS#396813
*/
request = RESET_CTL_CAT_ERROR;
mask = RESET_CTL_CAT_ERROR;
/* Catastrophic errors need to be cleared by HW */
ack = 0;
} else if (!(ack & RESET_CTL_READY_TO_RESET)) {
request = RESET_CTL_REQUEST_RESET;
mask = RESET_CTL_READY_TO_RESET;
ack = RESET_CTL_READY_TO_RESET;
} else {
return 0;
}
intel_uncore_write_fw(uncore, reg, _MASKED_BIT_ENABLE(request));
ret = __intel_wait_for_register_fw(uncore, reg, mask, ack,
700, 0, NULL);
if (ret)
DRM_ERROR("%s reset request timed out: {request: %08x, RESET_CTL: %08x}\n",
engine->name, request,
intel_uncore_read_fw(uncore, reg));
return ret;
}
static void gen8_engine_reset_cancel(struct intel_engine_cs *engine)
{
intel_uncore_write_fw(engine->uncore,
RING_RESET_CTL(engine->mmio_base),
_MASKED_BIT_DISABLE(RESET_CTL_REQUEST_RESET));
}
static int gen8_reset_engines(struct intel_gt *gt,
intel_engine_mask_t engine_mask,
unsigned int retry)
{
struct intel_engine_cs *engine;
const bool reset_non_ready = retry >= 1;
intel_engine_mask_t tmp;
int ret;
for_each_engine_masked(engine, gt, engine_mask, tmp) {
ret = gen8_engine_reset_prepare(engine);
if (ret && !reset_non_ready)
goto skip_reset;
/*
* If this is not the first failed attempt to prepare,
* we decide to proceed anyway.
*
* By doing so we risk context corruption and with
* some gens (kbl), possible system hang if reset
* happens during active bb execution.
*
* We rather take context corruption instead of
* failed reset with a wedged driver/gpu. And
* active bb execution case should be covered by
* stop_engines() we have before the reset.
*/
}
if (INTEL_GEN(gt->i915) >= 11)
ret = gen11_reset_engines(gt, engine_mask, retry);
else
ret = gen6_reset_engines(gt, engine_mask, retry);
skip_reset:
for_each_engine_masked(engine, gt, engine_mask, tmp)
gen8_engine_reset_cancel(engine);
return ret;
}
static int mock_reset(struct intel_gt *gt,
intel_engine_mask_t mask,
unsigned int retry)
{
return 0;
}
typedef int (*reset_func)(struct intel_gt *,
intel_engine_mask_t engine_mask,
unsigned int retry);
static reset_func intel_get_gpu_reset(const struct intel_gt *gt)
{
struct drm_i915_private *i915 = gt->i915;
if (is_mock_gt(gt))
return mock_reset;
else if (INTEL_GEN(i915) >= 8)
return gen8_reset_engines;
else if (INTEL_GEN(i915) >= 6)
return gen6_reset_engines;
else if (INTEL_GEN(i915) >= 5)
return ironlake_do_reset;
else if (IS_G4X(i915))
return g4x_do_reset;
else if (IS_G33(i915) || IS_PINEVIEW(i915))
return g33_do_reset;
else if (INTEL_GEN(i915) >= 3)
return i915_do_reset;
else
return NULL;
}
int __intel_gt_reset(struct intel_gt *gt, intel_engine_mask_t engine_mask)
{
const int retries = engine_mask == ALL_ENGINES ? RESET_MAX_RETRIES : 1;
reset_func reset;
int ret = -ETIMEDOUT;
int retry;
reset = intel_get_gpu_reset(gt);
if (!reset)
return -ENODEV;
/*
* If the power well sleeps during the reset, the reset
* request may be dropped and never completes (causing -EIO).
*/
intel_uncore_forcewake_get(gt->uncore, FORCEWAKE_ALL);
for (retry = 0; ret == -ETIMEDOUT && retry < retries; retry++) {
GEM_TRACE("engine_mask=%x\n", engine_mask);
preempt_disable();
ret = reset(gt, engine_mask, retry);
preempt_enable();
}
intel_uncore_forcewake_put(gt->uncore, FORCEWAKE_ALL);
return ret;
}
bool intel_has_gpu_reset(const struct intel_gt *gt)
{
if (!i915_modparams.reset)
return NULL;
return intel_get_gpu_reset(gt);
}
bool intel_has_reset_engine(const struct intel_gt *gt)
{
if (i915_modparams.reset < 2)
return false;
return INTEL_INFO(gt->i915)->has_reset_engine;
}
int intel_reset_guc(struct intel_gt *gt)
{
u32 guc_domain =
INTEL_GEN(gt->i915) >= 11 ? GEN11_GRDOM_GUC : GEN9_GRDOM_GUC;
int ret;
GEM_BUG_ON(!HAS_GT_UC(gt->i915));
intel_uncore_forcewake_get(gt->uncore, FORCEWAKE_ALL);
ret = gen6_hw_domain_reset(gt, guc_domain);
intel_uncore_forcewake_put(gt->uncore, FORCEWAKE_ALL);
return ret;
}
/*
* Ensure irq handler finishes, and not run again.
* Also return the active request so that we only search for it once.
*/
static void reset_prepare_engine(struct intel_engine_cs *engine)
{
/*
* During the reset sequence, we must prevent the engine from
* entering RC6. As the context state is undefined until we restart
* the engine, if it does enter RC6 during the reset, the state
* written to the powercontext is undefined and so we may lose
* GPU state upon resume, i.e. fail to restart after a reset.
*/
intel_uncore_forcewake_get(engine->uncore, FORCEWAKE_ALL);
engine->reset.prepare(engine);
}
static void revoke_mmaps(struct intel_gt *gt)
{
int i;
for (i = 0; i < gt->ggtt->num_fences; i++) {
struct drm_vma_offset_node *node;
struct i915_vma *vma;
u64 vma_offset;
vma = READ_ONCE(gt->ggtt->fence_regs[i].vma);
if (!vma)
continue;
if (!i915_vma_has_userfault(vma))
continue;
GEM_BUG_ON(vma->fence != &gt->ggtt->fence_regs[i]);
node = &vma->obj->base.vma_node;
vma_offset = vma->ggtt_view.partial.offset << PAGE_SHIFT;
unmap_mapping_range(gt->i915->drm.anon_inode->i_mapping,
drm_vma_node_offset_addr(node) + vma_offset,
vma->size,
1);
}
}
static intel_engine_mask_t reset_prepare(struct intel_gt *gt)
{
struct intel_engine_cs *engine;
intel_engine_mask_t awake = 0;
enum intel_engine_id id;
for_each_engine(engine, gt, id) {
if (intel_engine_pm_get_if_awake(engine))
awake |= engine->mask;
reset_prepare_engine(engine);
}
intel_uc_reset_prepare(&gt->uc);
return awake;
}
static void gt_revoke(struct intel_gt *gt)
{
revoke_mmaps(gt);
}
static int gt_reset(struct intel_gt *gt, intel_engine_mask_t stalled_mask)
{
struct intel_engine_cs *engine;
enum intel_engine_id id;
int err;
/*
* Everything depends on having the GTT running, so we need to start
* there.
*/
err = i915_ggtt_enable_hw(gt->i915);
if (err)
return err;
for_each_engine(engine, gt, id)
__intel_engine_reset(engine, stalled_mask & engine->mask);
i915_gem_restore_fences(gt->ggtt);
return err;
}
static void reset_finish_engine(struct intel_engine_cs *engine)
{
engine->reset.finish(engine);
intel_uncore_forcewake_put(engine->uncore, FORCEWAKE_ALL);
intel_engine_breadcrumbs_irq(engine);
}
static void reset_finish(struct intel_gt *gt, intel_engine_mask_t awake)
{
struct intel_engine_cs *engine;
enum intel_engine_id id;
for_each_engine(engine, gt, id) {
reset_finish_engine(engine);
if (awake & engine->mask)
intel_engine_pm_put(engine);
}
}
static void nop_submit_request(struct i915_request *request)
{
struct intel_engine_cs *engine = request->engine;
unsigned long flags;
GEM_TRACE("%s fence %llx:%lld -> -EIO\n",
engine->name, request->fence.context, request->fence.seqno);
dma_fence_set_error(&request->fence, -EIO);
spin_lock_irqsave(&engine->active.lock, flags);
__i915_request_submit(request);
i915_request_mark_complete(request);
spin_unlock_irqrestore(&engine->active.lock, flags);
intel_engine_queue_breadcrumbs(engine);
}
static void __intel_gt_set_wedged(struct intel_gt *gt)
{
struct intel_engine_cs *engine;
intel_engine_mask_t awake;
enum intel_engine_id id;
if (test_bit(I915_WEDGED, &gt->reset.flags))
return;
if (GEM_SHOW_DEBUG() && !intel_engines_are_idle(gt)) {
struct drm_printer p = drm_debug_printer(__func__);
for_each_engine(engine, gt, id)
intel_engine_dump(engine, &p, "%s\n", engine->name);
}
GEM_TRACE("start\n");
/*
* First, stop submission to hw, but do not yet complete requests by
* rolling the global seqno forward (since this would complete requests
* for which we haven't set the fence error to EIO yet).
*/
awake = reset_prepare(gt);
/* Even if the GPU reset fails, it should still stop the engines */
if (!INTEL_INFO(gt->i915)->gpu_reset_clobbers_display)
__intel_gt_reset(gt, ALL_ENGINES);
for_each_engine(engine, gt, id)
engine->submit_request = nop_submit_request;
/*
* Make sure no request can slip through without getting completed by
* either this call here to intel_engine_write_global_seqno, or the one
* in nop_submit_request.
*/
synchronize_rcu_expedited();
set_bit(I915_WEDGED, &gt->reset.flags);
/* Mark all executing requests as skipped */
for_each_engine(engine, gt, id)
engine->cancel_requests(engine);
reset_finish(gt, awake);
GEM_TRACE("end\n");
}
void intel_gt_set_wedged(struct intel_gt *gt)
{
intel_wakeref_t wakeref;
mutex_lock(&gt->reset.mutex);
with_intel_runtime_pm(gt->uncore->rpm, wakeref)
__intel_gt_set_wedged(gt);
mutex_unlock(&gt->reset.mutex);
}
static bool __intel_gt_unset_wedged(struct intel_gt *gt)
{
struct intel_gt_timelines *timelines = &gt->timelines;
struct intel_timeline *tl;
unsigned long flags;
bool ok;
if (!test_bit(I915_WEDGED, &gt->reset.flags))
return true;
/* Never fully initialised, recovery impossible */
if (test_bit(I915_WEDGED_ON_INIT, &gt->reset.flags))
return false;
GEM_TRACE("start\n");
/*
* Before unwedging, make sure that all pending operations
* are flushed and errored out - we may have requests waiting upon
* third party fences. We marked all inflight requests as EIO, and
* every execbuf since returned EIO, for consistency we want all
* the currently pending requests to also be marked as EIO, which
* is done inside our nop_submit_request - and so we must wait.
*
* No more can be submitted until we reset the wedged bit.
*/
spin_lock_irqsave(&timelines->lock, flags);
list_for_each_entry(tl, &timelines->active_list, link) {
struct dma_fence *fence;
fence = i915_active_fence_get(&tl->last_request);
if (!fence)
continue;
spin_unlock_irqrestore(&timelines->lock, flags);
/*
* All internal dependencies (i915_requests) will have
* been flushed by the set-wedge, but we may be stuck waiting
* for external fences. These should all be capped to 10s
* (I915_FENCE_TIMEOUT) so this wait should not be unbounded
* in the worst case.
*/
dma_fence_default_wait(fence, false, MAX_SCHEDULE_TIMEOUT);
dma_fence_put(fence);
/* Restart iteration after droping lock */
spin_lock_irqsave(&timelines->lock, flags);
tl = list_entry(&timelines->active_list, typeof(*tl), link);
}
spin_unlock_irqrestore(&timelines->lock, flags);
/* We must reset pending GPU events before restoring our submission */
ok = !HAS_EXECLISTS(gt->i915); /* XXX better agnosticism desired */
if (!INTEL_INFO(gt->i915)->gpu_reset_clobbers_display)
ok = __intel_gt_reset(gt, ALL_ENGINES) == 0;
if (!ok) {
/*
* Warn CI about the unrecoverable wedged condition.
* Time for a reboot.
*/
add_taint_for_CI(TAINT_WARN);
return false;
}
/*
* Undo nop_submit_request. We prevent all new i915 requests from
* being queued (by disallowing execbuf whilst wedged) so having
* waited for all active requests above, we know the system is idle
* and do not have to worry about a thread being inside
* engine->submit_request() as we swap over. So unlike installing
* the nop_submit_request on reset, we can do this from normal
* context and do not require stop_machine().
*/
intel_engines_reset_default_submission(gt);
GEM_TRACE("end\n");
smp_mb__before_atomic(); /* complete takeover before enabling execbuf */
clear_bit(I915_WEDGED, &gt->reset.flags);
return true;
}
bool intel_gt_unset_wedged(struct intel_gt *gt)
{
bool result;
mutex_lock(&gt->reset.mutex);
result = __intel_gt_unset_wedged(gt);
mutex_unlock(&gt->reset.mutex);
return result;
}
static int do_reset(struct intel_gt *gt, intel_engine_mask_t stalled_mask)
{
int err, i;
gt_revoke(gt);
err = __intel_gt_reset(gt, ALL_ENGINES);
for (i = 0; err && i < RESET_MAX_RETRIES; i++) {
msleep(10 * (i + 1));
err = __intel_gt_reset(gt, ALL_ENGINES);
}
if (err)
return err;
return gt_reset(gt, stalled_mask);
}
static int resume(struct intel_gt *gt)
{
struct intel_engine_cs *engine;
enum intel_engine_id id;
int ret;
for_each_engine(engine, gt, id) {
ret = engine->resume(engine);
if (ret)
return ret;
}
return 0;
}
/**
* intel_gt_reset - reset chip after a hang
* @gt: #intel_gt to reset
* @stalled_mask: mask of the stalled engines with the guilty requests
* @reason: user error message for why we are resetting
*
* Reset the chip. Useful if a hang is detected. Marks the device as wedged
* on failure.
*
* Procedure is fairly simple:
* - reset the chip using the reset reg
* - re-init context state
* - re-init hardware status page
* - re-init ring buffer
* - re-init interrupt state
* - re-init display
*/
void intel_gt_reset(struct intel_gt *gt,
intel_engine_mask_t stalled_mask,
const char *reason)
{
intel_engine_mask_t awake;
int ret;
GEM_TRACE("flags=%lx\n", gt->reset.flags);
might_sleep();
GEM_BUG_ON(!test_bit(I915_RESET_BACKOFF, &gt->reset.flags));
mutex_lock(&gt->reset.mutex);
/* Clear any previous failed attempts at recovery. Time to try again. */
if (!__intel_gt_unset_wedged(gt))
goto unlock;
if (reason)
dev_notice(gt->i915->drm.dev,
"Resetting chip for %s\n", reason);
atomic_inc(&gt->i915->gpu_error.reset_count);
awake = reset_prepare(gt);
if (!intel_has_gpu_reset(gt)) {
if (i915_modparams.reset)
dev_err(gt->i915->drm.dev, "GPU reset not supported\n");
else
DRM_DEBUG_DRIVER("GPU reset disabled\n");
goto error;
}
if (INTEL_INFO(gt->i915)->gpu_reset_clobbers_display)
intel_runtime_pm_disable_interrupts(gt->i915);
if (do_reset(gt, stalled_mask)) {
dev_err(gt->i915->drm.dev, "Failed to reset chip\n");
goto taint;
}
if (INTEL_INFO(gt->i915)->gpu_reset_clobbers_display)
intel_runtime_pm_enable_interrupts(gt->i915);
intel_overlay_reset(gt->i915);
/*
* Next we need to restore the context, but we don't use those
* yet either...
*
* Ring buffer needs to be re-initialized in the KMS case, or if X
* was running at the time of the reset (i.e. we weren't VT
* switched away).
*/
ret = intel_gt_init_hw(gt);
if (ret) {
DRM_ERROR("Failed to initialise HW following reset (%d)\n",
ret);
goto taint;
}
ret = resume(gt);
if (ret)
goto taint;
finish:
reset_finish(gt, awake);
unlock:
mutex_unlock(&gt->reset.mutex);
return;
taint:
/*
* History tells us that if we cannot reset the GPU now, we
* never will. This then impacts everything that is run
* subsequently. On failing the reset, we mark the driver
* as wedged, preventing further execution on the GPU.
* We also want to go one step further and add a taint to the
* kernel so that any subsequent faults can be traced back to
* this failure. This is important for CI, where if the
* GPU/driver fails we would like to reboot and restart testing
* rather than continue on into oblivion. For everyone else,
* the system should still plod along, but they have been warned!
*/
add_taint_for_CI(TAINT_WARN);
error:
__intel_gt_set_wedged(gt);
goto finish;
}
static inline int intel_gt_reset_engine(struct intel_engine_cs *engine)
{
return __intel_gt_reset(engine->gt, engine->mask);
}
/**
* intel_engine_reset - reset GPU engine to recover from a hang
* @engine: engine to reset
* @msg: reason for GPU reset; or NULL for no dev_notice()
*
* Reset a specific GPU engine. Useful if a hang is detected.
* Returns zero on successful reset or otherwise an error code.
*
* Procedure is:
* - identifies the request that caused the hang and it is dropped
* - reset engine (which will force the engine to idle)
* - re-init/configure engine
*/
int intel_engine_reset(struct intel_engine_cs *engine, const char *msg)
{
struct intel_gt *gt = engine->gt;
int ret;
GEM_TRACE("%s flags=%lx\n", engine->name, gt->reset.flags);
GEM_BUG_ON(!test_bit(I915_RESET_ENGINE + engine->id, &gt->reset.flags));
if (!intel_engine_pm_get_if_awake(engine))
return 0;
reset_prepare_engine(engine);
if (msg)
dev_notice(engine->i915->drm.dev,
"Resetting %s for %s\n", engine->name, msg);
atomic_inc(&engine->i915->gpu_error.reset_engine_count[engine->uabi_class]);
if (!engine->gt->uc.guc.execbuf_client)
ret = intel_gt_reset_engine(engine);
else
ret = intel_guc_reset_engine(&engine->gt->uc.guc, engine);
if (ret) {
/* If we fail here, we expect to fallback to a global reset */
DRM_DEBUG_DRIVER("%sFailed to reset %s, ret=%d\n",
engine->gt->uc.guc.execbuf_client ? "GuC " : "",
engine->name, ret);
goto out;
}
/*
* The request that caused the hang is stuck on elsp, we know the
* active request and can drop it, adjust head to skip the offending
* request to resume executing remaining requests in the queue.
*/
__intel_engine_reset(engine, true);
/*
* The engine and its registers (and workarounds in case of render)
* have been reset to their default values. Follow the init_ring
* process to program RING_MODE, HWSP and re-enable submission.
*/
ret = engine->resume(engine);
out:
intel_engine_cancel_stop_cs(engine);
reset_finish_engine(engine);
intel_engine_pm_put_async(engine);
return ret;
}
static void intel_gt_reset_global(struct intel_gt *gt,
u32 engine_mask,
const char *reason)
{
struct kobject *kobj = &gt->i915->drm.primary->kdev->kobj;
char *error_event[] = { I915_ERROR_UEVENT "=1", NULL };
char *reset_event[] = { I915_RESET_UEVENT "=1", NULL };
char *reset_done_event[] = { I915_ERROR_UEVENT "=0", NULL };
struct intel_wedge_me w;
kobject_uevent_env(kobj, KOBJ_CHANGE, error_event);
DRM_DEBUG_DRIVER("resetting chip\n");
kobject_uevent_env(kobj, KOBJ_CHANGE, reset_event);
/* Use a watchdog to ensure that our reset completes */
intel_wedge_on_timeout(&w, gt, 5 * HZ) {
intel_prepare_reset(gt->i915);
/* Flush everyone using a resource about to be clobbered */
synchronize_srcu_expedited(&gt->reset.backoff_srcu);
intel_gt_reset(gt, engine_mask, reason);
intel_finish_reset(gt->i915);
}
if (!test_bit(I915_WEDGED, &gt->reset.flags))
kobject_uevent_env(kobj, KOBJ_CHANGE, reset_done_event);
}
/**
* intel_gt_handle_error - handle a gpu error
* @gt: the intel_gt
* @engine_mask: mask representing engines that are hung
* @flags: control flags
* @fmt: Error message format string
*
* Do some basic checking of register state at error time and
* dump it to the syslog. Also call i915_capture_error_state() to make
* sure we get a record and make it available in debugfs. Fire a uevent
* so userspace knows something bad happened (should trigger collection
* of a ring dump etc.).
*/
void intel_gt_handle_error(struct intel_gt *gt,
intel_engine_mask_t engine_mask,
unsigned long flags,
const char *fmt, ...)
{
struct intel_engine_cs *engine;
intel_wakeref_t wakeref;
intel_engine_mask_t tmp;
char error_msg[80];
char *msg = NULL;
if (fmt) {
va_list args;
va_start(args, fmt);
vscnprintf(error_msg, sizeof(error_msg), fmt, args);
va_end(args);
msg = error_msg;
}
/*
* In most cases it's guaranteed that we get here with an RPM
* reference held, for example because there is a pending GPU
* request that won't finish until the reset is done. This
* isn't the case at least when we get here by doing a
* simulated reset via debugfs, so get an RPM reference.
*/
wakeref = intel_runtime_pm_get(gt->uncore->rpm);
engine_mask &= INTEL_INFO(gt->i915)->engine_mask;
if (flags & I915_ERROR_CAPTURE) {
i915_capture_error_state(gt->i915, engine_mask, msg);
intel_gt_clear_error_registers(gt, engine_mask);
}
/*
* Try engine reset when available. We fall back to full reset if
* single reset fails.
*/
if (intel_has_reset_engine(gt) && !intel_gt_is_wedged(gt)) {
for_each_engine_masked(engine, gt, engine_mask, tmp) {
BUILD_BUG_ON(I915_RESET_MODESET >= I915_RESET_ENGINE);
if (test_and_set_bit(I915_RESET_ENGINE + engine->id,
&gt->reset.flags))
continue;
if (intel_engine_reset(engine, msg) == 0)
engine_mask &= ~engine->mask;
clear_and_wake_up_bit(I915_RESET_ENGINE + engine->id,
&gt->reset.flags);
}
}
if (!engine_mask)
goto out;
/* Full reset needs the mutex, stop any other user trying to do so. */
if (test_and_set_bit(I915_RESET_BACKOFF, &gt->reset.flags)) {
wait_event(gt->reset.queue,
!test_bit(I915_RESET_BACKOFF, &gt->reset.flags));
goto out; /* piggy-back on the other reset */
}
/* Make sure i915_reset_trylock() sees the I915_RESET_BACKOFF */
synchronize_rcu_expedited();
/* Prevent any other reset-engine attempt. */
for_each_engine(engine, gt, tmp) {
while (test_and_set_bit(I915_RESET_ENGINE + engine->id,
&gt->reset.flags))
wait_on_bit(&gt->reset.flags,
I915_RESET_ENGINE + engine->id,
TASK_UNINTERRUPTIBLE);
}
intel_gt_reset_global(gt, engine_mask, msg);
for_each_engine(engine, gt, tmp)
clear_bit_unlock(I915_RESET_ENGINE + engine->id,
&gt->reset.flags);
clear_bit_unlock(I915_RESET_BACKOFF, &gt->reset.flags);
smp_mb__after_atomic();
wake_up_all(&gt->reset.queue);
out:
intel_runtime_pm_put(gt->uncore->rpm, wakeref);
}
int intel_gt_reset_trylock(struct intel_gt *gt, int *srcu)
{
might_lock(&gt->reset.backoff_srcu);
might_sleep();
rcu_read_lock();
while (test_bit(I915_RESET_BACKOFF, &gt->reset.flags)) {
rcu_read_unlock();
if (wait_event_interruptible(gt->reset.queue,
!test_bit(I915_RESET_BACKOFF,
&gt->reset.flags)))
return -EINTR;
rcu_read_lock();
}
*srcu = srcu_read_lock(&gt->reset.backoff_srcu);
rcu_read_unlock();
return 0;
}
void intel_gt_reset_unlock(struct intel_gt *gt, int tag)
__releases(&gt->reset.backoff_srcu)
{
srcu_read_unlock(&gt->reset.backoff_srcu, tag);
}
int intel_gt_terminally_wedged(struct intel_gt *gt)
{
might_sleep();
if (!intel_gt_is_wedged(gt))
return 0;
/* Reset still in progress? Maybe we will recover? */
if (!test_bit(I915_RESET_BACKOFF, &gt->reset.flags))
return -EIO;
if (wait_event_interruptible(gt->reset.queue,
!test_bit(I915_RESET_BACKOFF,
&gt->reset.flags)))
return -EINTR;
return intel_gt_is_wedged(gt) ? -EIO : 0;
}
void intel_gt_set_wedged_on_init(struct intel_gt *gt)
{
BUILD_BUG_ON(I915_RESET_ENGINE + I915_NUM_ENGINES >
I915_WEDGED_ON_INIT);
intel_gt_set_wedged(gt);
set_bit(I915_WEDGED_ON_INIT, &gt->reset.flags);
}
void intel_gt_init_reset(struct intel_gt *gt)
{
init_waitqueue_head(&gt->reset.queue);
mutex_init(&gt->reset.mutex);
init_srcu_struct(&gt->reset.backoff_srcu);
}
void intel_gt_fini_reset(struct intel_gt *gt)
{
cleanup_srcu_struct(&gt->reset.backoff_srcu);
}
static void intel_wedge_me(struct work_struct *work)
{
struct intel_wedge_me *w = container_of(work, typeof(*w), work.work);
dev_err(w->gt->i915->drm.dev,
"%s timed out, cancelling all in-flight rendering.\n",
w->name);
intel_gt_set_wedged(w->gt);
}
void __intel_init_wedge(struct intel_wedge_me *w,
struct intel_gt *gt,
long timeout,
const char *name)
{
w->gt = gt;
w->name = name;
INIT_DELAYED_WORK_ONSTACK(&w->work, intel_wedge_me);
schedule_delayed_work(&w->work, timeout);
}
void __intel_fini_wedge(struct intel_wedge_me *w)
{
cancel_delayed_work_sync(&w->work);
destroy_delayed_work_on_stack(&w->work);
w->gt = NULL;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
#include "selftest_reset.c"
#include "selftest_hangcheck.c"
#endif