1 files changed, 27 insertions, 53 deletions

diff --git a/drivers/gpu/drm/i915/intel_guc_submission.c b/drivers/gpu/drm/i915/intel_guc_submission.c
index 07b9d313b019..a81f04d46e87 100644
--- a/drivers/gpu/drm/i915/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/intel_guc_submission.c
@@ -557,16 +557,36 @@ static void inject_preempt_context(struct work_struct *work)
                                              preempt_work[engine->id]);
         struct intel_guc_client *client = guc->preempt_client;
         struct guc_stage_desc *stage_desc = __get_stage_desc(client);
-        u32 ctx_desc = lower_32_bits(to_intel_context(client->owner,
-                                                      engine)->lrc_desc);
+        struct intel_context *ce = to_intel_context(client->owner, engine);
         u32 data[7];
 
-        /*
-         * The ring contains commands to write GUC_PREEMPT_FINISHED into HWSP.
-         * See guc_fill_preempt_context().
-         */
+        if (!ce->ring->emit) { /* recreate upon load/resume */
+                u32 addr = intel_hws_preempt_done_address(engine);
+                u32 *cs;
+
+                cs = ce->ring->vaddr;
+                if (engine->id == RCS) {
+                        cs = gen8_emit_ggtt_write_rcs(cs,
+                                                      GUC_PREEMPT_FINISHED,
+                                                      addr);
+                } else {
+                        cs = gen8_emit_ggtt_write(cs,
+                                                  GUC_PREEMPT_FINISHED,
+                                                  addr);
+                        *cs++ = MI_NOOP;
+                        *cs++ = MI_NOOP;
+                }
+                *cs++ = MI_USER_INTERRUPT;
+                *cs++ = MI_NOOP;
+
+                ce->ring->emit = GUC_PREEMPT_BREADCRUMB_BYTES;
+                GEM_BUG_ON((void *)cs - ce->ring->vaddr != ce->ring->emit);
+
+                flush_ggtt_writes(ce->ring->vma);
+        }
+
         spin_lock_irq(&client->wq_lock);
-        guc_wq_item_append(client, engine->guc_id, ctx_desc,
+        guc_wq_item_append(client, engine->guc_id, lower_32_bits(ce->lrc_desc),
                            GUC_PREEMPT_BREADCRUMB_BYTES / sizeof(u64), 0);
         spin_unlock_irq(&client->wq_lock);
 
@@ -1044,50 +1064,6 @@ static inline bool ctx_save_restore_disabled(struct intel_context *ce)
 #undef SR_DISABLED
 }
 
-static void guc_fill_preempt_context(struct intel_guc *guc)
-{
-        struct drm_i915_private *dev_priv = guc_to_i915(guc);
-        struct intel_guc_client *client = guc->preempt_client;
-        struct intel_engine_cs *engine;
-        enum intel_engine_id id;
-
-        for_each_engine(engine, dev_priv, id) {
-                struct intel_context *ce =
-                        to_intel_context(client->owner, engine);
-                u32 addr = intel_hws_preempt_done_address(engine);
-                u32 *cs;
-
-                GEM_BUG_ON(!ce->pin_count);
-
-                /*
-                 * We rely on this context image *not* being saved after
-                 * preemption. This ensures that the RING_HEAD / RING_TAIL
-                 * remain pointing at initial values forever.
-                 */
-                GEM_BUG_ON(!ctx_save_restore_disabled(ce));
-
-                cs = ce->ring->vaddr;
-                if (id == RCS) {
-                        cs = gen8_emit_ggtt_write_rcs(cs,
-                                                      GUC_PREEMPT_FINISHED,
-                                                      addr);
-                } else {
-                        cs = gen8_emit_ggtt_write(cs,
-                                                  GUC_PREEMPT_FINISHED,
-                                                  addr);
-                        *cs++ = MI_NOOP;
-                        *cs++ = MI_NOOP;
-                }
-                *cs++ = MI_USER_INTERRUPT;
-                *cs++ = MI_NOOP;
-
-                GEM_BUG_ON((void *)cs - ce->ring->vaddr !=
-                           GUC_PREEMPT_BREADCRUMB_BYTES);
-
-                flush_ggtt_writes(ce->ring->vma);
-        }
-}
-
 static int guc_clients_create(struct intel_guc *guc)
 {
         struct drm_i915_private *dev_priv = guc_to_i915(guc);
@@ -1118,8 +1094,6 @@ static int guc_clients_create(struct intel_guc *guc)
                         return PTR_ERR(client);
                 }
                 guc->preempt_client = client;
-
-                guc_fill_preempt_context(guc);
         }
 
         return 0;