drm/i915/guc: Reset implementation for new GuC interface

Reset implementation for new GuC interface. This is the legacy reset
implementation which is called when the i915 owns the engine hang check.
Future patches will offload the engine hang check to GuC but we will
continue to maintain this legacy path as a fallback and this code path
is also required if the GuC dies.

With the new GuC interface it is not possible to reset individual
engines - it is only possible to reset the GPU entirely. This patch
forces an entire chip reset if any engine hangs.

v2:
 (Michal)
  - Check for -EPIPE rather than -EIO (CT deadlock/corrupt check)
v3:
 (John H)
  - Split into a series of smaller patches
v4:
 (John H)
  - Fix typo
  - Add braces around if statements in reset code
v5:
 (Checkpatch)
  - Fix warnings

Cc: John Harrison <john.c.harrison@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: John Harrison <john.c.harrison@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-9-matthew.brost@intel.com

1 files changed, 12 insertions, 6 deletions

diff --git a/drivers/gpu/drm/i915/gt/intel_reset.c b/drivers/gpu/drm/i915/gt/intel_reset.c
index 9586613ee399..721a10e2215e 100644
--- a/drivers/gpu/drm/i915/gt/intel_reset.c
+++ b/drivers/gpu/drm/i915/gt/intel_reset.c
@@ -832,6 +832,8 @@ static int gt_reset(struct intel_gt *gt, intel_engine_mask_t stalled_mask)
 		__intel_engine_reset(engine, stalled_mask & engine->mask);
 	local_bh_enable();
 
+	intel_uc_reset(&gt->uc, true);
+
 	intel_ggtt_restore_fences(gt->ggtt);
 
 	return err;
@@ -856,6 +858,8 @@ static void reset_finish(struct intel_gt *gt, intel_engine_mask_t awake)
 		if (awake & engine->mask)
 			intel_engine_pm_put(engine);
 	}
+
+	intel_uc_reset_finish(&gt->uc);
 }
 
 static void nop_submit_request(struct i915_request *request)
@@ -909,6 +913,7 @@ static void __intel_gt_set_wedged(struct intel_gt *gt)
 	for_each_engine(engine, gt, id)
 		if (engine->reset.cancel)
 			engine->reset.cancel(engine);
+	intel_uc_cancel_requests(&gt->uc);
 	local_bh_enable();
 
 	reset_finish(gt, awake);
@@ -1197,6 +1202,9 @@ int __intel_engine_reset_bh(struct intel_engine_cs *engine, const char *msg)
 	ENGINE_TRACE(engine, "flags=%lx\n", gt->reset.flags);
 	GEM_BUG_ON(!test_bit(I915_RESET_ENGINE + engine->id, &gt->reset.flags));
 
+	if (intel_engine_uses_guc(engine))
+		return -ENODEV;
+
 	if (!intel_engine_pm_get_if_awake(engine))
 		return 0;
 
@@ -1207,13 +1215,10 @@ int __intel_engine_reset_bh(struct intel_engine_cs *engine, const char *msg)
 			   "Resetting %s for %s\n", engine->name, msg);
 	atomic_inc(&engine->i915->gpu_error.reset_engine_count[engine->uabi_class]);
 
-	if (intel_engine_uses_guc(engine))
-		ret = intel_guc_reset_engine(&engine->gt->uc.guc, engine);
-	else
-		ret = intel_gt_reset_engine(engine);
+	ret = intel_gt_reset_engine(engine);
 	if (ret) {
 		/* If we fail here, we expect to fallback to a global reset */
-		ENGINE_TRACE(engine, "Failed to reset, err: %d\n", ret);
+		ENGINE_TRACE(engine, "Failed to reset %s, err: %d\n", engine->name, ret);
 		goto out;
 	}
 
@@ -1347,7 +1352,8 @@ void intel_gt_handle_error(struct intel_gt *gt,
 	 * Try engine reset when available. We fall back to full reset if
 	 * single reset fails.
 	 */
-	if (intel_has_reset_engine(gt) && !intel_gt_is_wedged(gt)) {
+	if (!intel_uc_uses_guc_submission(&gt->uc) &&
+	    intel_has_reset_engine(gt) && !intel_gt_is_wedged(gt)) {
 		local_bh_disable();
 		for_each_engine_masked(engine, gt, engine_mask, tmp) {
 			BUILD_BUG_ON(I915_RESET_MODESET >= I915_RESET_ENGINE);