[Intel-xe] [PATCH 2/2] drm/xe: nuke GuC on unload

[Matthew Auld]

On PVC unloading followed by reloading the module often results in a
completely dead machine (seems to be plaguing CI). Resetting the GuC
like we do at load seems to cure it at least when locally testing this.

References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/542
References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/597
Signed-off-by: Matthew Auld <matthew.auld at intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
---
 drivers/gpu/drm/xe/xe_guc.c | 16 ++++++++++++++++
 drivers/gpu/drm/xe/xe_uc.c  |  5 +++++
 drivers/gpu/drm/xe/xe_uc.h  |  1 +
 3 files changed, 22 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_guc.c b/drivers/gpu/drm/xe/xe_guc.c
index e102637c0695..bbe06686a706 100644
--- a/drivers/gpu/drm/xe/xe_guc.c
+++ b/drivers/gpu/drm/xe/xe_guc.c
@@ -5,6 +5,8 @@
 
 #include "xe_guc.h"
 
+#include <drm/drm_managed.h>
+
 #include "generated/xe_wa_oob.h"
 #include "regs/xe_gt_regs.h"
 #include "regs/xe_guc_regs.h"
@@ -20,6 +22,7 @@
 #include "xe_guc_submit.h"
 #include "xe_mmio.h"
 #include "xe_platform_types.h"
+#include "xe_uc.h"
 #include "xe_uc_fw.h"
 #include "xe_wa.h"
 #include "xe_wopcm.h"
@@ -217,6 +220,15 @@ static void guc_write_params(struct xe_guc *guc)
 		xe_mmio_write32(gt, SOFT_SCRATCH(1 + i), guc->params[i]);
 }
 
+static void guc_fini(struct drm_device *drm, void *arg)
+{
+	struct xe_guc *guc = arg;
+
+	xe_force_wake_get(gt_to_fw(guc_to_gt(guc)), XE_FORCEWAKE_ALL);
+	xe_uc_fini_hw(&guc_to_gt(guc)->uc);
+	xe_force_wake_put(gt_to_fw(guc_to_gt(guc)), XE_FORCEWAKE_ALL);
+}
+
 int xe_guc_init(struct xe_guc *guc)
 {
 	struct xe_device *xe = guc_to_xe(guc);
@@ -240,6 +252,10 @@ int xe_guc_init(struct xe_guc *guc)
 	if (ret)
 		goto out;
 
+	ret = drmm_add_action_or_reset(&gt_to_xe(gt)->drm, guc_fini, guc);
+	if (ret)
+		goto out;
+
 	ret = xe_guc_pc_init(&guc->pc);
 	if (ret)
 		goto out;
diff --git a/drivers/gpu/drm/xe/xe_uc.c b/drivers/gpu/drm/xe/xe_uc.c
index addd6f2681b9..9c8ce504f4da 100644
--- a/drivers/gpu/drm/xe/xe_uc.c
+++ b/drivers/gpu/drm/xe/xe_uc.c
@@ -167,6 +167,11 @@ int xe_uc_init_hw(struct xe_uc *uc)
 	return 0;
 }
 
+int xe_uc_fini_hw(struct xe_uc *uc)
+{
+	return xe_uc_sanitize_reset(uc);
+}
+
 int xe_uc_reset_prepare(struct xe_uc *uc)
 {
 	/* GuC submission not enabled, nothing to do */
diff --git a/drivers/gpu/drm/xe/xe_uc.h b/drivers/gpu/drm/xe/xe_uc.h
index 42219b361df5..4109ae7028af 100644
--- a/drivers/gpu/drm/xe/xe_uc.h
+++ b/drivers/gpu/drm/xe/xe_uc.h
@@ -12,6 +12,7 @@ int xe_uc_init(struct xe_uc *uc);
 int xe_uc_init_hwconfig(struct xe_uc *uc);
 int xe_uc_init_post_hwconfig(struct xe_uc *uc);
 int xe_uc_init_hw(struct xe_uc *uc);
+int xe_uc_fini_hw(struct xe_uc *uc);
 void xe_uc_gucrc_disable(struct xe_uc *uc);
 int xe_uc_reset_prepare(struct xe_uc *uc);
 void xe_uc_stop_prepare(struct xe_uc *uc);
-- 
2.41.0