From: Michal Wajdeczko <michal.wajdeczko@intel.com>
Date: Mon, 28 May 2018 17:16:18 +0000
Subject: drm/i915/guc: Don't read SOFT_SCRATCH(15) on MMIO error
Git-commit: 13295bd887d07a9d904401808f41a8d35946d8c2
Patch-mainline: v4.19-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

SOFT_SCRATCH(15) is used by GuC for sending MMIO GuC events to host and
those events are now handled by intel_guc_to_host_event_handler_mmio().

We should not try to read it on MMIO action error as 1) we may be using
different set of registers for GuC MMIO communication, and 2) GuC may
use CTB mechanism for sending events to host.

While here, upgrade error message to DRM_ERROR.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180528171618.10436-1-michal.wajdeczko@intel.com

Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/i915/intel_guc.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

--- a/drivers/gpu/drm/i915/intel_guc.c
+++ b/drivers/gpu/drm/i915/intel_guc.c
@@ -346,10 +346,8 @@ int intel_guc_send_mmio(struct intel_guc
 		ret = -EIO;
 
 	if (ret) {
-		DRM_DEBUG_DRIVER("INTEL_GUC_SEND: Action 0x%X failed;"
-				 " ret=%d status=0x%08X response=0x%08X\n",
-				 action[0], ret, status,
-				 I915_READ(SOFT_SCRATCH(15)));
+		DRM_ERROR("MMIO: GuC action %#x failed with error %d %#x\n",
+			  action[0], ret, status);
 		goto out;
 	}