[PATCH] drm/xe/guc: Make creation of SLPC debugfs files conditional

[Aradhya Bhatia]

Platforms that do not support SLPC are exempted from the GuC PC support.
The GuC PC does not get initialized, and neither do its BOs get created.

This causes a problem because the GuC PC debugfs file is still being
created. Whenever the file is attempted to read, it causes a NULL
pointer dereference on the supposed BO of the GuC PC.

So, make the creation of SLPC debugfs files conditional to when SLPC
features are supported.

Suggested-by: Matt Roper <matthew.d.roper at intel.com>
Signed-off-by: Aradhya Bhatia <aradhya.bhatia at intel.com>
---
 drivers/gpu/drm/xe/xe_guc_debugfs.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_guc_debugfs.c b/drivers/gpu/drm/xe/xe_guc_debugfs.c
index f33013f8a0f3..0b102ab46c4d 100644
--- a/drivers/gpu/drm/xe/xe_guc_debugfs.c
+++ b/drivers/gpu/drm/xe/xe_guc_debugfs.c
@@ -113,23 +113,34 @@ static const struct drm_info_list vf_safe_debugfs_list[] = {
 	{ "guc_ctb", .show = guc_debugfs_show, .data = guc_ctb },
 };
 
+/* For GuC debugfs files that require the SLPC support */
+static const struct drm_info_list slpc_debugfs_list[] = {
+	{ "guc_pc", .show = guc_debugfs_show, .data = guc_pc },
+};
+
 /* everything else should be added here */
 static const struct drm_info_list pf_only_debugfs_list[] = {
 	{ "guc_log", .show = guc_debugfs_show, .data = guc_log },
 	{ "guc_log_dmesg", .show = guc_debugfs_show, .data = guc_log_dmesg },
-	{ "guc_pc", .show = guc_debugfs_show, .data = guc_pc },
 };
 
 void xe_guc_debugfs_register(struct xe_guc *guc, struct dentry *parent)
 {
-	struct drm_minor *minor = guc_to_xe(guc)->drm.primary;
+	struct xe_device *xe =  guc_to_xe(guc);
+	struct drm_minor *minor = xe->drm.primary;
 
 	drm_debugfs_create_files(vf_safe_debugfs_list,
 				 ARRAY_SIZE(vf_safe_debugfs_list),
 				 parent, minor);
 
-	if (!IS_SRIOV_VF(guc_to_xe(guc)))
+	if (!IS_SRIOV_VF(xe)) {
 		drm_debugfs_create_files(pf_only_debugfs_list,
 					 ARRAY_SIZE(pf_only_debugfs_list),
 					 parent, minor);
+
+		if (!xe->info.skip_guc_pc)
+			drm_debugfs_create_files(slpc_debugfs_list,
+						 ARRAY_SIZE(slpc_debugfs_list),
+						 parent, minor);
+	}
 }

base-commit: 3d6670fab64cb00b5e6ed80d2517147db533faf1
-- 
2.43.0