diff options
| -rw-r--r-- | drivers/gpu/drm/i915/intel_lrc.c | 22 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/intel_ringbuffer.h | 1 |
2 files changed, 23 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index 4aed00323780..8d0c49388863 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -477,6 +477,7 @@ static void execlists_submit_ports(struct intel_engine_cs *engine) elsp_write(desc, elsp); } + execlists_clear_active(&engine->execlists, EXECLISTS_ACTIVE_HWACK); } static bool ctx_single_port_submission(const struct i915_gem_context *ctx) @@ -529,6 +530,7 @@ static void inject_preempt_context(struct intel_engine_cs *engine) elsp_write(0, elsp); elsp_write(ce->lrc_desc, elsp); + execlists_clear_active(&engine->execlists, EXECLISTS_ACTIVE_HWACK); } static void execlists_dequeue(struct intel_engine_cs *engine) @@ -575,9 +577,20 @@ static void execlists_dequeue(struct intel_engine_cs *engine) * know the next preemption status we see corresponds * to this ELSP update. */ + GEM_BUG_ON(!port_count(&port[0])); if (port_count(&port[0]) > 1) goto unlock; + /* + * If we write to ELSP a second time before the HW has had + * a chance to respond to the previous write, we can confuse + * the HW and hit "undefined behaviour". After writing to ELSP, + * we must then wait until we see a context-switch event from + * the HW to indicate that it has had a chance to respond. + */ + if (!execlists_is_active(execlists, EXECLISTS_ACTIVE_HWACK)) + goto unlock; + if (HAS_LOGICAL_RING_PREEMPTION(engine->i915) && rb_entry(rb, struct i915_priolist, node)->priority > max(last->priotree.priority, 0)) { @@ -871,6 +884,15 @@ static void execlists_submission_tasklet(unsigned long data) GEM_TRACE("%s csb[%dd]: status=0x%08x:0x%08x\n", engine->name, head, status, buf[2*head + 1]); + + if (status & (GEN8_CTX_STATUS_IDLE_ACTIVE | + GEN8_CTX_STATUS_PREEMPTED)) + execlists_set_active(execlists, + EXECLISTS_ACTIVE_HWACK); + if (status & GEN8_CTX_STATUS_ACTIVE_IDLE) + execlists_clear_active(execlists, + EXECLISTS_ACTIVE_HWACK); + if (!(status & GEN8_CTX_STATUS_COMPLETED_MASK)) continue; diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h index c00804ed64c6..e437a9556c08 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.h +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h @@ -251,6 +251,7 @@ struct intel_engine_execlists { unsigned int active; #define EXECLISTS_ACTIVE_USER 0 #define EXECLISTS_ACTIVE_PREEMPT 1 +#define EXECLISTS_ACTIVE_HWACK 2 /** * @port_mask: number of execlist ports - 1 |