@@ -4455,6 +4455,235 @@ static int live_gpr_clear(void *arg)
return err;
}
+static struct i915_request *
+create_timestamp(struct intel_context *ce, void *slot, int idx)
+{
+ const u32 offset =
+ i915_ggtt_offset(ce->engine->status_page.vma) +
+ offset_in_page(slot);
+ struct i915_request *rq;
+ u32 *cs;
+ int err;
+
+ rq = intel_context_create_request(ce);
+ if (IS_ERR(rq))
+ return rq;
+
+ cs = intel_ring_begin(rq, 10);
+ if (IS_ERR(cs)) {
+ err = PTR_ERR(cs);
+ goto err;
+ }
+
+ *cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
+ *cs++ = MI_NOOP;
+
+ *cs++ = MI_SEMAPHORE_WAIT |
+ MI_SEMAPHORE_GLOBAL_GTT |
+ MI_SEMAPHORE_POLL |
+ MI_SEMAPHORE_SAD_NEQ_SDD;
+ *cs++ = 0;
+ *cs++ = offset;
+ *cs++ = 0;
+
+ *cs++ = MI_STORE_REGISTER_MEM_GEN8 | MI_USE_GGTT;
+ *cs++ = i915_mmio_reg_offset(RING_CTX_TIMESTAMP(rq->engine->mmio_base));
+ *cs++ = offset + idx * sizeof(u32);
+ *cs++ = 0;
+
+ intel_ring_advance(rq, cs);
+
+ rq->sched.attr.priority = I915_PRIORITY_MASK;
+ err = 0;
+err:
+ i915_request_get(rq);
+ i915_request_add(rq);
+ if (err) {
+ i915_request_put(rq);
+ return ERR_PTR(err);
+ }
+
+ return rq;
+}
+
+static int
+emit_timestamp_release(struct intel_context *ce, void *slot)
+{
+ const u32 offset =
+ i915_ggtt_offset(ce->engine->status_page.vma) +
+ offset_in_page(slot);
+ struct i915_request *rq;
+ u32 *cs;
+
+ rq = intel_context_create_request(ce);
+ if (IS_ERR(rq))
+ return PTR_ERR(rq);
+
+ cs = intel_ring_begin(rq, 4);
+ if (IS_ERR(cs)) {
+ i915_request_add(rq);
+ return PTR_ERR(cs);
+ }
+
+ *cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
+ *cs++ = offset;
+ *cs++ = 0;
+ *cs++ = 1;
+
+ intel_ring_advance(rq, cs);
+
+ rq->sched.attr.priority = I915_PRIORITY_BARRIER;
+ i915_request_add(rq);
+ return 0;
+}
+
+struct lrc_timestamp {
+ struct intel_engine_cs *engine;
+ struct intel_context *ce[2];
+ u32 poison;
+};
+
+static bool timestamp_advanced(u32 start, u32 end)
+{
+ return (s32)(end - start) > 0;
+}
+
+static int __lrc_timestamp(const struct lrc_timestamp *arg, bool preempt)
+{
+ u32 *slot = memset32(arg->engine->status_page.addr + 1000, 0, 4);
+ struct i915_request *rq;
+ u32 timestamp;
+ int err = 0;
+
+ arg->ce[0]->lrc_reg_state[CTX_TIMESTAMP] = arg->poison;
+ rq = create_timestamp(arg->ce[0], slot, 1);
+ if (IS_ERR(rq))
+ return PTR_ERR(rq);
+
+ err = wait_for_submit(rq->engine, rq, HZ / 2);
+ if (err)
+ goto err;
+
+ if (preempt) {
+ arg->ce[1]->lrc_reg_state[CTX_TIMESTAMP] = 0xdeadbeef;
+ err = emit_timestamp_release(arg->ce[1], slot);
+ if (err)
+ goto err;
+ } else {
+ slot[0] = 1;
+ wmb();
+ }
+
+ if (i915_request_wait(rq, 0, HZ / 2) < 0) {
+ err = -ETIME;
+ goto err;
+ }
+
+ /* and wait for switch to kernel */
+ if (igt_flush_test(arg->engine->i915)) {
+ err = -EIO;
+ goto err;
+ }
+
+ rmb();
+
+ if (!timestamp_advanced(arg->poison, slot[1])) {
+ pr_err("%s(%s): invalid timestamp on restore, context:%x, request:%x\n",
+ arg->engine->name, preempt ? "preempt" : "simple",
+ arg->poison, slot[1]);
+ err = -EINVAL;
+ }
+
+ timestamp = READ_ONCE(arg->ce[0]->lrc_reg_state[CTX_TIMESTAMP]);
+ if (!timestamp_advanced(slot[1], timestamp)) {
+ pr_err("%s(%s): invalid timestamp on save, request:%x, context:%x\n",
+ arg->engine->name, preempt ? "preempt" : "simple",
+ slot[1], timestamp);
+ err = -EINVAL;
+ }
+
+err:
+ memset32(slot, -1, 4);
+ i915_request_put(rq);
+ return err;
+}
+
+static int live_lrc_timestamp(void *arg)
+{
+ struct intel_gt *gt = arg;
+ enum intel_engine_id id;
+ struct lrc_timestamp data;
+ const u32 poison[] = {
+ 0,
+ S32_MAX,
+ (u32)S32_MAX + 1,
+ U32_MAX,
+ };
+
+ /*
+ * We want to verify that the timestamp is saved and restore across
+ * context switches and is monotonic.
+ *
+ * So we do this with a little bit of LRC poisoning to check various
+ * boundary conditions, and see what happens if we preempt the context
+ * with a second request (carrying more poison into the timestamp).
+ */
+
+ for_each_engine(data.engine, gt, id) {
+ unsigned long heartbeat;
+ int i, err = 0;
+
+ engine_heartbeat_disable(data.engine, &heartbeat);
+
+ for (i = 0; i < ARRAY_SIZE(data.ce); i++) {
+ struct intel_context *tmp;
+
+ tmp = intel_context_create(data.engine);
+ if (IS_ERR(tmp)) {
+ err = PTR_ERR(tmp);
+ goto err;
+ }
+
+ err = intel_context_pin(tmp);
+ if (err) {
+ intel_context_put(tmp);
+ goto err;
+ }
+
+ data.ce[i] = tmp;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(poison); i++) {
+ data.poison = poison[i];
+
+ err = __lrc_timestamp(&data, false);
+ if (err)
+ break;
+
+ err = __lrc_timestamp(&data, true);
+ if (err)
+ break;
+ }
+
+err:
+ engine_heartbeat_enable(data.engine, heartbeat);
+ for (i = 0; i < ARRAY_SIZE(data.ce); i++) {
+ if (!data.ce[i])
+ break;
+
+ intel_context_unpin(data.ce[i]);
+ intel_context_put(data.ce[i]);
+ }
+
+ if (igt_flush_test(gt->i915))
+ err = -EIO;
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
static int __live_pphwsp_runtime(struct intel_engine_cs *engine)
{
struct intel_context *ce;
@@ -4552,6 +4781,7 @@ int intel_lrc_live_selftests(struct drm_i915_private *i915)
SUBTEST(live_lrc_fixed),
SUBTEST(live_lrc_state),
SUBTEST(live_gpr_clear),
+ SUBTEST(live_lrc_timestamp),
SUBTEST(live_pphwsp_runtime),
};
Check that the CTX_TIMESTAMP is monotonic across context save/restore and upon preemption. References: https://gitlab.freedesktop.org/drm/intel/issues/1233 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> --- drivers/gpu/drm/i915/gt/selftest_lrc.c | 230 +++++++++++++++++++++++++ 1 file changed, 230 insertions(+)