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path: root/drivers/gpu/drm/i915/selftests/intel_workarounds.c
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Diffstat (limited to 'drivers/gpu/drm/i915/selftests/intel_workarounds.c')
-rw-r--r--drivers/gpu/drm/i915/selftests/intel_workarounds.c521
1 files changed, 471 insertions, 50 deletions
diff --git a/drivers/gpu/drm/i915/selftests/intel_workarounds.c b/drivers/gpu/drm/i915/selftests/intel_workarounds.c
index 67017d5175b8..3baed59008d7 100644
--- a/drivers/gpu/drm/i915/selftests/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/selftests/intel_workarounds.c
@@ -5,20 +5,75 @@
*/
#include "../i915_selftest.h"
+#include "../i915_reset.h"
#include "igt_flush_test.h"
#include "igt_reset.h"
#include "igt_spinner.h"
#include "igt_wedge_me.h"
#include "mock_context.h"
+#include "mock_drm.h"
+
+static const struct wo_register {
+ enum intel_platform platform;
+ u32 reg;
+} wo_registers[] = {
+ { INTEL_GEMINILAKE, 0x731c }
+};
+
+#define REF_NAME_MAX (INTEL_ENGINE_CS_MAX_NAME + 4)
+struct wa_lists {
+ struct i915_wa_list gt_wa_list;
+ struct {
+ char name[REF_NAME_MAX];
+ struct i915_wa_list wa_list;
+ } engine[I915_NUM_ENGINES];
+};
+
+static void
+reference_lists_init(struct drm_i915_private *i915, struct wa_lists *lists)
+{
+ struct intel_engine_cs *engine;
+ enum intel_engine_id id;
+
+ memset(lists, 0, sizeof(*lists));
+
+ wa_init_start(&lists->gt_wa_list, "GT_REF");
+ gt_init_workarounds(i915, &lists->gt_wa_list);
+ wa_init_finish(&lists->gt_wa_list);
+
+ for_each_engine(engine, i915, id) {
+ struct i915_wa_list *wal = &lists->engine[id].wa_list;
+ char *name = lists->engine[id].name;
+
+ snprintf(name, REF_NAME_MAX, "%s_REF", engine->name);
+
+ wa_init_start(wal, name);
+ engine_init_workarounds(engine, wal);
+ wa_init_finish(wal);
+ }
+}
+
+static void
+reference_lists_fini(struct drm_i915_private *i915, struct wa_lists *lists)
+{
+ struct intel_engine_cs *engine;
+ enum intel_engine_id id;
+
+ for_each_engine(engine, i915, id)
+ intel_wa_list_free(&lists->engine[id].wa_list);
+
+ intel_wa_list_free(&lists->gt_wa_list);
+}
static struct drm_i915_gem_object *
read_nonprivs(struct i915_gem_context *ctx, struct intel_engine_cs *engine)
{
+ const u32 base = engine->mmio_base;
struct drm_i915_gem_object *result;
+ intel_wakeref_t wakeref;
struct i915_request *rq;
struct i915_vma *vma;
- const u32 base = engine->mmio_base;
u32 srm, *cs;
int err;
int i;
@@ -27,7 +82,7 @@ read_nonprivs(struct i915_gem_context *ctx, struct intel_engine_cs *engine)
if (IS_ERR(result))
return result;
- i915_gem_object_set_cache_level(result, I915_CACHE_LLC);
+ i915_gem_object_set_cache_coherency(result, I915_CACHE_LLC);
cs = i915_gem_object_pin_map(result, I915_MAP_WB);
if (IS_ERR(cs)) {
@@ -35,6 +90,7 @@ read_nonprivs(struct i915_gem_context *ctx, struct intel_engine_cs *engine)
goto err_obj;
}
memset(cs, 0xc5, PAGE_SIZE);
+ i915_gem_object_flush_map(result);
i915_gem_object_unpin_map(result);
vma = i915_vma_instance(result, &engine->i915->ggtt.vm, NULL);
@@ -47,9 +103,9 @@ read_nonprivs(struct i915_gem_context *ctx, struct intel_engine_cs *engine)
if (err)
goto err_obj;
- intel_runtime_pm_get(engine->i915);
- rq = i915_request_alloc(engine, ctx);
- intel_runtime_pm_put(engine->i915);
+ rq = ERR_PTR(-ENODEV);
+ with_intel_runtime_pm(engine->i915, wakeref)
+ rq = i915_request_alloc(engine, ctx);
if (IS_ERR(rq)) {
err = PTR_ERR(rq);
goto err_pin;
@@ -134,7 +190,7 @@ static int check_whitelist(struct i915_gem_context *ctx,
err = 0;
igt_wedge_on_timeout(&wedge, ctx->i915, HZ / 5) /* a safety net! */
err = i915_gem_object_set_to_cpu_domain(results, false);
- if (i915_terminally_wedged(&ctx->i915->gpu_error))
+ if (i915_terminally_wedged(ctx->i915))
err = -EIO;
if (err)
goto out_put;
@@ -167,8 +223,7 @@ out_put:
static int do_device_reset(struct intel_engine_cs *engine)
{
- set_bit(I915_RESET_HANDOFF, &engine->i915->gpu_error.flags);
- i915_reset(engine->i915, ENGINE_MASK(engine->id), "live_workarounds");
+ i915_reset(engine->i915, engine->mask, "live_workarounds");
return 0;
}
@@ -183,20 +238,18 @@ switch_to_scratch_context(struct intel_engine_cs *engine,
{
struct i915_gem_context *ctx;
struct i915_request *rq;
+ intel_wakeref_t wakeref;
int err = 0;
ctx = kernel_context(engine->i915);
if (IS_ERR(ctx))
return PTR_ERR(ctx);
- intel_runtime_pm_get(engine->i915);
+ GEM_BUG_ON(i915_gem_context_is_bannable(ctx));
- if (spin)
+ rq = ERR_PTR(-ENODEV);
+ with_intel_runtime_pm(engine->i915, wakeref)
rq = igt_spinner_create_request(spin, ctx, engine, MI_NOOP);
- else
- rq = i915_request_alloc(engine, ctx);
-
- intel_runtime_pm_put(engine->i915);
kernel_context_close(ctx);
@@ -225,19 +278,17 @@ static int check_whitelist_across_reset(struct intel_engine_cs *engine,
const char *name)
{
struct drm_i915_private *i915 = engine->i915;
- bool want_spin = reset == do_engine_reset;
struct i915_gem_context *ctx;
struct igt_spinner spin;
+ intel_wakeref_t wakeref;
int err;
pr_info("Checking %d whitelisted registers (RING_NONPRIV) [%s]\n",
engine->whitelist.count, name);
- if (want_spin) {
- err = igt_spinner_init(&spin, i915);
- if (err)
- return err;
- }
+ err = igt_spinner_init(&spin, i915);
+ if (err)
+ return err;
ctx = kernel_context(i915);
if (IS_ERR(ctx))
@@ -249,18 +300,15 @@ static int check_whitelist_across_reset(struct intel_engine_cs *engine,
goto out;
}
- err = switch_to_scratch_context(engine, want_spin ? &spin : NULL);
+ err = switch_to_scratch_context(engine, &spin);
if (err)
goto out;
- intel_runtime_pm_get(i915);
- err = reset(engine);
- intel_runtime_pm_put(i915);
+ with_intel_runtime_pm(i915, wakeref)
+ err = reset(engine);
- if (want_spin) {
- igt_spinner_end(&spin);
- igt_spinner_fini(&spin);
- }
+ igt_spinner_end(&spin);
+ igt_spinner_fini(&spin);
if (err) {
pr_err("%s reset failed\n", name);
@@ -292,10 +340,379 @@ out:
return err;
}
+static struct i915_vma *create_scratch(struct i915_gem_context *ctx)
+{
+ struct drm_i915_gem_object *obj;
+ struct i915_vma *vma;
+ void *ptr;
+ int err;
+
+ obj = i915_gem_object_create_internal(ctx->i915, PAGE_SIZE);
+ if (IS_ERR(obj))
+ return ERR_CAST(obj);
+
+ i915_gem_object_set_cache_coherency(obj, I915_CACHE_LLC);
+
+ ptr = i915_gem_object_pin_map(obj, I915_MAP_WB);
+ if (IS_ERR(ptr)) {
+ err = PTR_ERR(ptr);
+ goto err_obj;
+ }
+ memset(ptr, 0xc5, PAGE_SIZE);
+ i915_gem_object_flush_map(obj);
+ i915_gem_object_unpin_map(obj);
+
+ vma = i915_vma_instance(obj, &ctx->ppgtt->vm, NULL);
+ if (IS_ERR(vma)) {
+ err = PTR_ERR(vma);
+ goto err_obj;
+ }
+
+ err = i915_vma_pin(vma, 0, 0, PIN_USER);
+ if (err)
+ goto err_obj;
+
+ err = i915_gem_object_set_to_cpu_domain(obj, false);
+ if (err)
+ goto err_obj;
+
+ return vma;
+
+err_obj:
+ i915_gem_object_put(obj);
+ return ERR_PTR(err);
+}
+
+static struct i915_vma *create_batch(struct i915_gem_context *ctx)
+{
+ struct drm_i915_gem_object *obj;
+ struct i915_vma *vma;
+ int err;
+
+ obj = i915_gem_object_create_internal(ctx->i915, 16 * PAGE_SIZE);
+ if (IS_ERR(obj))
+ return ERR_CAST(obj);
+
+ vma = i915_vma_instance(obj, &ctx->ppgtt->vm, NULL);
+ if (IS_ERR(vma)) {
+ err = PTR_ERR(vma);
+ goto err_obj;
+ }
+
+ err = i915_vma_pin(vma, 0, 0, PIN_USER);
+ if (err)
+ goto err_obj;
+
+ err = i915_gem_object_set_to_wc_domain(obj, true);
+ if (err)
+ goto err_obj;
+
+ return vma;
+
+err_obj:
+ i915_gem_object_put(obj);
+ return ERR_PTR(err);
+}
+
+static u32 reg_write(u32 old, u32 new, u32 rsvd)
+{
+ if (rsvd == 0x0000ffff) {
+ old &= ~(new >> 16);
+ old |= new & (new >> 16);
+ } else {
+ old &= ~rsvd;
+ old |= new & rsvd;
+ }
+
+ return old;
+}
+
+static bool wo_register(struct intel_engine_cs *engine, u32 reg)
+{
+ enum intel_platform platform = INTEL_INFO(engine->i915)->platform;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(wo_registers); i++) {
+ if (wo_registers[i].platform == platform &&
+ wo_registers[i].reg == reg)
+ return true;
+ }
+
+ return false;
+}
+
+static int check_dirty_whitelist(struct i915_gem_context *ctx,
+ struct intel_engine_cs *engine)
+{
+ const u32 values[] = {
+ 0x00000000,
+ 0x01010101,
+ 0x10100101,
+ 0x03030303,
+ 0x30300303,
+ 0x05050505,
+ 0x50500505,
+ 0x0f0f0f0f,
+ 0xf00ff00f,
+ 0x10101010,
+ 0xf0f01010,
+ 0x30303030,
+ 0xa0a03030,
+ 0x50505050,
+ 0xc0c05050,
+ 0xf0f0f0f0,
+ 0x11111111,
+ 0x33333333,
+ 0x55555555,
+ 0x0000ffff,
+ 0x00ff00ff,
+ 0xff0000ff,
+ 0xffff00ff,
+ 0xffffffff,
+ };
+ struct i915_vma *scratch;
+ struct i915_vma *batch;
+ int err = 0, i, v;
+ u32 *cs, *results;
+
+ scratch = create_scratch(ctx);
+ if (IS_ERR(scratch))
+ return PTR_ERR(scratch);
+
+ batch = create_batch(ctx);
+ if (IS_ERR(batch)) {
+ err = PTR_ERR(batch);
+ goto out_scratch;
+ }
+
+ for (i = 0; i < engine->whitelist.count; i++) {
+ u32 reg = i915_mmio_reg_offset(engine->whitelist.list[i].reg);
+ u64 addr = scratch->node.start;
+ struct i915_request *rq;
+ u32 srm, lrm, rsvd;
+ u32 expect;
+ int idx;
+
+ if (wo_register(engine, reg))
+ continue;
+
+ srm = MI_STORE_REGISTER_MEM;
+ lrm = MI_LOAD_REGISTER_MEM;
+ if (INTEL_GEN(ctx->i915) >= 8)
+ lrm++, srm++;
+
+ pr_debug("%s: Writing garbage to %x\n",
+ engine->name, reg);
+
+ cs = i915_gem_object_pin_map(batch->obj, I915_MAP_WC);
+ if (IS_ERR(cs)) {
+ err = PTR_ERR(cs);
+ goto out_batch;
+ }
+
+ /* SRM original */
+ *cs++ = srm;
+ *cs++ = reg;
+ *cs++ = lower_32_bits(addr);
+ *cs++ = upper_32_bits(addr);
+
+ idx = 1;
+ for (v = 0; v < ARRAY_SIZE(values); v++) {
+ /* LRI garbage */
+ *cs++ = MI_LOAD_REGISTER_IMM(1);
+ *cs++ = reg;
+ *cs++ = values[v];
+
+ /* SRM result */
+ *cs++ = srm;
+ *cs++ = reg;
+ *cs++ = lower_32_bits(addr + sizeof(u32) * idx);
+ *cs++ = upper_32_bits(addr + sizeof(u32) * idx);
+ idx++;
+ }
+ for (v = 0; v < ARRAY_SIZE(values); v++) {
+ /* LRI garbage */
+ *cs++ = MI_LOAD_REGISTER_IMM(1);
+ *cs++ = reg;
+ *cs++ = ~values[v];
+
+ /* SRM result */
+ *cs++ = srm;
+ *cs++ = reg;
+ *cs++ = lower_32_bits(addr + sizeof(u32) * idx);
+ *cs++ = upper_32_bits(addr + sizeof(u32) * idx);
+ idx++;
+ }
+ GEM_BUG_ON(idx * sizeof(u32) > scratch->size);
+
+ /* LRM original -- don't leave garbage in the context! */
+ *cs++ = lrm;
+ *cs++ = reg;
+ *cs++ = lower_32_bits(addr);
+ *cs++ = upper_32_bits(addr);
+
+ *cs++ = MI_BATCH_BUFFER_END;
+
+ i915_gem_object_flush_map(batch->obj);
+ i915_gem_object_unpin_map(batch->obj);
+ i915_gem_chipset_flush(ctx->i915);
+
+ rq = i915_request_alloc(engine, ctx);
+ if (IS_ERR(rq)) {
+ err = PTR_ERR(rq);
+ goto out_batch;
+ }
+
+ if (engine->emit_init_breadcrumb) { /* Be nice if we hang */
+ err = engine->emit_init_breadcrumb(rq);
+ if (err)
+ goto err_request;
+ }
+
+ err = engine->emit_bb_start(rq,
+ batch->node.start, PAGE_SIZE,
+ 0);
+ if (err)
+ goto err_request;
+
+err_request:
+ i915_request_add(rq);
+ if (err)
+ goto out_batch;
+
+ if (i915_request_wait(rq, I915_WAIT_LOCKED, HZ / 5) < 0) {
+ pr_err("%s: Futzing %x timedout; cancelling test\n",
+ engine->name, reg);
+ i915_gem_set_wedged(ctx->i915);
+ err = -EIO;
+ goto out_batch;
+ }
+
+ results = i915_gem_object_pin_map(scratch->obj, I915_MAP_WB);
+ if (IS_ERR(results)) {
+ err = PTR_ERR(results);
+ goto out_batch;
+ }
+
+ GEM_BUG_ON(values[ARRAY_SIZE(values) - 1] != 0xffffffff);
+ rsvd = results[ARRAY_SIZE(values)]; /* detect write masking */
+ if (!rsvd) {
+ pr_err("%s: Unable to write to whitelisted register %x\n",
+ engine->name, reg);
+ err = -EINVAL;
+ goto out_unpin;
+ }
+
+ expect = results[0];
+ idx = 1;
+ for (v = 0; v < ARRAY_SIZE(values); v++) {
+ expect = reg_write(expect, values[v], rsvd);
+ if (results[idx] != expect)
+ err++;
+ idx++;
+ }
+ for (v = 0; v < ARRAY_SIZE(values); v++) {
+ expect = reg_write(expect, ~values[v], rsvd);
+ if (results[idx] != expect)
+ err++;
+ idx++;
+ }
+ if (err) {
+ pr_err("%s: %d mismatch between values written to whitelisted register [%x], and values read back!\n",
+ engine->name, err, reg);
+
+ pr_info("%s: Whitelisted register: %x, original value %08x, rsvd %08x\n",
+ engine->name, reg, results[0], rsvd);
+
+ expect = results[0];
+ idx = 1;
+ for (v = 0; v < ARRAY_SIZE(values); v++) {
+ u32 w = values[v];
+
+ expect = reg_write(expect, w, rsvd);
+ pr_info("Wrote %08x, read %08x, expect %08x\n",
+ w, results[idx], expect);
+ idx++;
+ }
+ for (v = 0; v < ARRAY_SIZE(values); v++) {
+ u32 w = ~values[v];
+
+ expect = reg_write(expect, w, rsvd);
+ pr_info("Wrote %08x, read %08x, expect %08x\n",
+ w, results[idx], expect);
+ idx++;
+ }
+
+ err = -EINVAL;
+ }
+out_unpin:
+ i915_gem_object_unpin_map(scratch->obj);
+ if (err)
+ break;
+ }
+
+ if (igt_flush_test(ctx->i915, I915_WAIT_LOCKED))
+ err = -EIO;
+out_batch:
+ i915_vma_unpin_and_release(&batch, 0);
+out_scratch:
+ i915_vma_unpin_and_release(&scratch, 0);
+ return err;
+}
+
+static int live_dirty_whitelist(void *arg)
+{
+ struct drm_i915_private *i915 = arg;
+ struct intel_engine_cs *engine;
+ struct i915_gem_context *ctx;
+ enum intel_engine_id id;
+ intel_wakeref_t wakeref;
+ struct drm_file *file;
+ int err = 0;
+
+ /* Can the user write to the whitelisted registers? */
+
+ if (INTEL_GEN(i915) < 7) /* minimum requirement for LRI, SRM, LRM */
+ return 0;
+
+ wakeref = intel_runtime_pm_get(i915);
+
+ mutex_unlock(&i915->drm.struct_mutex);
+ file = mock_file(i915);
+ mutex_lock(&i915->drm.struct_mutex);
+ if (IS_ERR(file)) {
+ err = PTR_ERR(file);
+ goto out_rpm;
+ }
+
+ ctx = live_context(i915, file);
+ if (IS_ERR(ctx)) {
+ err = PTR_ERR(ctx);
+ goto out_file;
+ }
+
+ for_each_engine(engine, i915, id) {
+ if (engine->whitelist.count == 0)
+ continue;
+
+ err = check_dirty_whitelist(ctx, engine);
+ if (err)
+ goto out_file;
+ }
+
+out_file:
+ mutex_unlock(&i915->drm.struct_mutex);
+ mock_file_free(i915, file);
+ mutex_lock(&i915->drm.struct_mutex);
+out_rpm:
+ intel_runtime_pm_put(i915, wakeref);
+ return err;
+}
+
static int live_reset_whitelist(void *arg)
{
struct drm_i915_private *i915 = arg;
- struct intel_engine_cs *engine = i915->engine[RCS];
+ struct intel_engine_cs *engine = i915->engine[RCS0];
int err = 0;
/* If we reset the gpu, we should not lose the RING_NONPRIV */
@@ -326,16 +743,17 @@ out:
return err;
}
-static bool verify_gt_engine_wa(struct drm_i915_private *i915, const char *str)
+static bool verify_gt_engine_wa(struct drm_i915_private *i915,
+ struct wa_lists *lists, const char *str)
{
struct intel_engine_cs *engine;
enum intel_engine_id id;
bool ok = true;
- ok &= intel_gt_verify_workarounds(i915, str);
+ ok &= wa_list_verify(i915, &lists->gt_wa_list, str);
for_each_engine(engine, i915, id)
- ok &= intel_engine_verify_workarounds(engine, str);
+ ok &= wa_list_verify(i915, &lists->engine[id].wa_list, str);
return ok;
}
@@ -344,7 +762,8 @@ static int
live_gpu_reset_gt_engine_workarounds(void *arg)
{
struct drm_i915_private *i915 = arg;
- struct i915_gpu_error *error = &i915->gpu_error;
+ intel_wakeref_t wakeref;
+ struct wa_lists lists;
bool ok;
if (!intel_has_gpu_reset(i915))
@@ -353,19 +772,21 @@ live_gpu_reset_gt_engine_workarounds(void *arg)
pr_info("Verifying after GPU reset...\n");
igt_global_reset_lock(i915);
+ wakeref = intel_runtime_pm_get(i915);
+
+ reference_lists_init(i915, &lists);
- ok = verify_gt_engine_wa(i915, "before reset");
+ ok = verify_gt_engine_wa(i915, &lists, "before reset");
if (!ok)
goto out;
- intel_runtime_pm_get(i915);
- set_bit(I915_RESET_HANDOFF, &error->flags);
i915_reset(i915, ALL_ENGINES, "live_workarounds");
- intel_runtime_pm_put(i915);
- ok = verify_gt_engine_wa(i915, "after reset");
+ ok = verify_gt_engine_wa(i915, &lists, "after reset");
out:
+ reference_lists_fini(i915, &lists);
+ intel_runtime_pm_put(i915, wakeref);
igt_global_reset_unlock(i915);
return ok ? 0 : -ESRCH;
@@ -380,6 +801,8 @@ live_engine_reset_gt_engine_workarounds(void *arg)
struct igt_spinner spin;
enum intel_engine_id id;
struct i915_request *rq;
+ intel_wakeref_t wakeref;
+ struct wa_lists lists;
int ret = 0;
if (!intel_has_reset_engine(i915))
@@ -390,23 +813,24 @@ live_engine_reset_gt_engine_workarounds(void *arg)
return PTR_ERR(ctx);
igt_global_reset_lock(i915);
+ wakeref = intel_runtime_pm_get(i915);
+
+ reference_lists_init(i915, &lists);
for_each_engine(engine, i915, id) {
bool ok;
pr_info("Verifying after %s reset...\n", engine->name);
- ok = verify_gt_engine_wa(i915, "before reset");
+ ok = verify_gt_engine_wa(i915, &lists, "before reset");
if (!ok) {
ret = -ESRCH;
goto err;
}
- intel_runtime_pm_get(i915);
i915_reset_engine(engine, "live_workarounds");
- intel_runtime_pm_put(i915);
- ok = verify_gt_engine_wa(i915, "after idle reset");
+ ok = verify_gt_engine_wa(i915, &lists, "after idle reset");
if (!ok) {
ret = -ESRCH;
goto err;
@@ -416,13 +840,10 @@ live_engine_reset_gt_engine_workarounds(void *arg)
if (ret)
goto err;
- intel_runtime_pm_get(i915);
-
rq = igt_spinner_create_request(&spin, ctx, engine, MI_NOOP);
if (IS_ERR(rq)) {
ret = PTR_ERR(rq);
igt_spinner_fini(&spin);
- intel_runtime_pm_put(i915);
goto err;
}
@@ -431,19 +852,16 @@ live_engine_reset_gt_engine_workarounds(void *arg)
if (!igt_wait_for_spinner(&spin, rq)) {
pr_err("Spinner failed to start\n");
igt_spinner_fini(&spin);
- intel_runtime_pm_put(i915);
ret = -ETIMEDOUT;
goto err;
}
i915_reset_engine(engine, "live_workarounds");
- intel_runtime_pm_put(i915);
-
igt_spinner_end(&spin);
igt_spinner_fini(&spin);
- ok = verify_gt_engine_wa(i915, "after busy reset");
+ ok = verify_gt_engine_wa(i915, &lists, "after busy reset");
if (!ok) {
ret = -ESRCH;
goto err;
@@ -451,6 +869,8 @@ live_engine_reset_gt_engine_workarounds(void *arg)
}
err:
+ reference_lists_fini(i915, &lists);
+ intel_runtime_pm_put(i915, wakeref);
igt_global_reset_unlock(i915);
kernel_context_close(ctx);
@@ -462,13 +882,14 @@ err:
int intel_workarounds_live_selftests(struct drm_i915_private *i915)
{
static const struct i915_subtest tests[] = {
+ SUBTEST(live_dirty_whitelist),
SUBTEST(live_reset_whitelist),
SUBTEST(live_gpu_reset_gt_engine_workarounds),
SUBTEST(live_engine_reset_gt_engine_workarounds),
};
int err;
- if (i915_terminally_wedged(&i915->gpu_error))
+ if (i915_terminally_wedged(i915))
return 0;
mutex_lock(&i915->drm.struct_mutex);