Reading from CTX_INFO upsets rc6, requiring us to detect and prevent
possible rc6 context corruption. Poke at the bear!
Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk>
Cc: Imre Deak <imre.d...@intel.com>
Cc: Mika Kuoppala <mika.kuopp...@linux.intel.com>
---
drivers/gpu/drm/i915/gt/intel_rc6.c | 4 +
drivers/gpu/drm/i915/gt/selftest_gt_pm.c | 13 ++
drivers/gpu/drm/i915/gt/selftest_rc6.c | 146 ++++++++++++++++++
drivers/gpu/drm/i915/gt/selftest_rc6.h | 12 ++
.../drm/i915/selftests/i915_live_selftests.h | 1 +
5 files changed, 176 insertions(+)
create mode 100644 drivers/gpu/drm/i915/gt/selftest_rc6.c
create mode 100644 drivers/gpu/drm/i915/gt/selftest_rc6.h
diff --git a/drivers/gpu/drm/i915/gt/intel_rc6.c
b/drivers/gpu/drm/i915/gt/intel_rc6.c
index 977a617a196d..7a0bc6dde009 100644
--- a/drivers/gpu/drm/i915/gt/intel_rc6.c
+++ b/drivers/gpu/drm/i915/gt/intel_rc6.c
@@ -783,3 +783,7 @@ u64 intel_rc6_residency_us(struct intel_rc6 *rc6,
i915_reg_t reg)
{
return DIV_ROUND_UP_ULL(intel_rc6_residency_ns(rc6, reg), 1000);
}
+
+#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
+#include "selftest_rc6.c"
+#endif
diff --git a/drivers/gpu/drm/i915/gt/selftest_gt_pm.c
b/drivers/gpu/drm/i915/gt/selftest_gt_pm.c
index d1752f15702a..1d5bf93d1258 100644
--- a/drivers/gpu/drm/i915/gt/selftest_gt_pm.c
+++ b/drivers/gpu/drm/i915/gt/selftest_gt_pm.c
@@ -6,6 +6,7 @@
*/
#include "selftest_llc.h"
+#include "selftest_rc6.h"
static int live_gt_resume(void *arg)
{
@@ -58,3 +59,15 @@ int intel_gt_pm_live_selftests(struct drm_i915_private *i915)
return intel_gt_live_subtests(tests, &i915->gt);
}
+
+int intel_gt_pm_late_selftests(struct drm_i915_private *i915)
+{
+ static const struct i915_subtest tests[] = {
+ SUBTEST(live_rc6_ctx),
+ };
+
+ if (intel_gt_is_wedged(&i915->gt))
+ return 0;
+
+ return intel_gt_live_subtests(tests, &i915->gt);
+}
diff --git a/drivers/gpu/drm/i915/gt/selftest_rc6.c
b/drivers/gpu/drm/i915/gt/selftest_rc6.c
new file mode 100644
index 000000000000..c8b729f7e93e
--- /dev/null
+++ b/drivers/gpu/drm/i915/gt/selftest_rc6.c
@@ -0,0 +1,146 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2019 Intel Corporation
+ */
+
+#include "intel_context.h"
+#include "intel_engine_pm.h"
+#include "intel_gt_requests.h"
+#include "intel_ring.h"
+#include "selftest_rc6.h"
+
+#include "selftests/i915_random.h"
+
+static const u32 *__live_rc6_ctx(struct intel_context *ce)
+{
+ struct i915_request *rq;
+ u32 const *result;
+ u32 cmd;
+ u32 *cs;
+
+ rq = intel_context_create_request(ce);
+ if (IS_ERR(rq))
+ return ERR_CAST(rq);
+
+ cs = intel_ring_begin(rq, 4);
+ if (IS_ERR(cs)) {
+ i915_request_add(rq);
+ return cs;
+ }
+
+ cmd = MI_STORE_REGISTER_MEM | MI_USE_GGTT;
+ if (INTEL_GEN(rq->i915) >= 8)
+ cmd++;
+
+ *cs++ = cmd;
+ *cs++ = i915_mmio_reg_offset(GEN8_RC6_CTX_INFO);
+ *cs++ = ce->timeline->hwsp_offset + 8;
+ *cs++ = 0;
+ intel_ring_advance(rq, cs);
+
+ result = rq->hwsp_seqno + 2;
+ i915_request_add(rq);
+
+ return result;
+}
+
+static struct intel_engine_cs **
+randomised_engines(struct intel_gt *gt,
+ struct rnd_state *prng,
+ unsigned int *count)
+{
+ struct intel_engine_cs *engine, **engines;
+ enum intel_engine_id id;
+ int n;
+
+ n = 0;
+ for_each_engine(engine, gt, id)
+ n++;
+ if (!n)
+ return NULL;
+
+ engines = kmalloc_array(n, sizeof(*engines), GFP_KERNEL);
+ if (!engines)
+ return NULL;
+
+ n = 0;
+ for_each_engine(engine, gt, id)
+ engines[n++] = engine;
+
+ i915_prandom_shuffle(engines, sizeof(*engines), n, prng);
+
+ *count = n;
+ return engines;
+}
+
+int live_rc6_ctx(void *arg)
+{
+ struct intel_gt *gt = arg;
+ struct intel_engine_cs **engines;
+ unsigned int n, count;
+ I915_RND_STATE(prng);
+ int err = 0;
+
+ /* A read of CTX_INFO upsets rc6. Poke the bear! */
+ if (INTEL_GEN(gt->i915) < 8)
+ return 0;
+
+ engines = randomised_engines(gt, &prng, &count);
+ if (!engines)
+ return 0;
+
+ for (n = 0; n < count; n++) {
+ struct intel_engine_cs *engine = engines[n];
+ int pass;
+
+ for (pass = 0; pass < 2; pass++) {
+ struct intel_context *ce;
+ unsigned int resets =
+ i915_reset_engine_count(>->i915->gpu_error,
+ engine);
+ const u32 *res;
+
+ /* Use a sacrifical context */
+ ce =
intel_context_create(engine->kernel_context->gem_context,
+ engine);
+ if (IS_ERR(ce)) {
+ err = PTR_ERR(ce);
+ goto out;
+ }
+
+ intel_engine_pm_get(engine);
+ res = __live_rc6_ctx(ce);
+ intel_engine_pm_put(engine);
+ intel_context_put(ce);
+ if (IS_ERR(res)) {
+ err = PTR_ERR(res);
+ goto out;
+ }
+
+ if (intel_gt_wait_for_idle(gt, HZ / 5) == -ETIME) {
+ intel_gt_set_wedged(gt);
+ err = -ETIME;
+ goto out;
+ }
+
+ intel_gt_pm_wait_for_idle(gt);
+ pr_debug("%s: CTX_INFO=%0x\n",
+ engine->name, READ_ONCE(*res));
+
+ if (resets !=
+ i915_reset_engine_count(>->i915->gpu_error,
+ engine)) {
+ pr_err("%s: GPU reset required\n",
+ engine->name);
+ add_taint_for_CI(TAINT_WARN);
+ err = -EIO;
+ goto out;
+ }
+ }
+ }
+
+out:
+ kfree(engines);
+ return err;
+}
diff --git a/drivers/gpu/drm/i915/gt/selftest_rc6.h
b/drivers/gpu/drm/i915/gt/selftest_rc6.h
new file mode 100644
index 000000000000..230c6b4c7dc0
--- /dev/null
+++ b/drivers/gpu/drm/i915/gt/selftest_rc6.h
@@ -0,0 +1,12 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2019 Intel Corporation
+ */
+
+#ifndef SELFTEST_RC6_H
+#define SELFTEST_RC6_H
+
+int live_rc6_ctx(void *arg);
+
+#endif /* SELFTEST_RC6_H */
diff --git a/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
b/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
index 11b40bc58e6d..beff59ee9f6f 100644
--- a/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
+++ b/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
@@ -39,3 +39,4 @@ selftest(hangcheck, intel_hangcheck_live_selftests)
selftest(execlists, intel_execlists_live_selftests)
selftest(guc, intel_guc_live_selftest)
selftest(perf, i915_perf_live_selftests)
+selftest(late_gt_pm, intel_gt_pm_late_selftests)
--
2.24.0
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