[PATCH 4/4] drm/i915/reset: Add "display_reset_count" debugfs file

[Ville Syrjala <ville.syrjala@linux.intel.com>]

From: Ville Syrjälä <ville.syrjala@linux.intel.com>

Expose the number of display resets performed in a new
"display_reset_count" debugfs file. kms_busy can use this to
confirm that the kernel actually took the full display reset path.

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Jouni Högander <jouni.hogander@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_display_core.h    |  4 ++++
 drivers/gpu/drm/i915/display/intel_display_debugfs.c |  2 ++
 drivers/gpu/drm/i915/display/intel_display_reset.c   | 10 ++++++++++
 drivers/gpu/drm/i915/display/intel_display_reset.h   |  2 ++
 drivers/gpu/drm/xe/Makefile                          |  1 +
 5 files changed, 19 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_display_core.h b/drivers/gpu/drm/i915/display/intel_display_core.h
index 9e77003addd0..38535d1056d1 100644
--- a/drivers/gpu/drm/i915/display/intel_display_core.h
+++ b/drivers/gpu/drm/i915/display/intel_display_core.h
@@ -556,6 +556,10 @@ struct intel_display {
 		unsigned long mask;
 	} quirks;
 
+	struct {
+		u32 count;
+	} reset;
+
 	struct {
 		/* restore state for suspend/resume and display reset */
 		struct drm_atomic_state *modeset_state;
diff --git a/drivers/gpu/drm/i915/display/intel_display_debugfs.c b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
index f244a2b5d139..81bef000a4e3 100644
--- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
+++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
@@ -27,6 +27,7 @@
 #include "intel_display_power.h"
 #include "intel_display_power_well.h"
 #include "intel_display_regs.h"
+#include "intel_display_reset.h"
 #include "intel_display_rpm.h"
 #include "intel_display_types.h"
 #include "intel_dmc.h"
@@ -838,6 +839,7 @@ void intel_display_debugfs_register(struct intel_display *display)
 
 	intel_bios_debugfs_register(display);
 	intel_cdclk_debugfs_register(display);
+	intel_display_reset_debugfs_register(display);
 	intel_dmc_debugfs_register(display);
 	intel_dp_test_debugfs_register(display);
 	intel_fbc_debugfs_register(display);
diff --git a/drivers/gpu/drm/i915/display/intel_display_reset.c b/drivers/gpu/drm/i915/display/intel_display_reset.c
index ca15dc18ef0f..79c2e77ca137 100644
--- a/drivers/gpu/drm/i915/display/intel_display_reset.c
+++ b/drivers/gpu/drm/i915/display/intel_display_reset.c
@@ -3,6 +3,8 @@
  * Copyright © 2023 Intel Corporation
  */
 
+#include <linux/debugfs.h>
+
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_print.h>
 
@@ -66,6 +68,7 @@ void intel_display_reset_prepare(struct intel_display *display)
 		return;
 	}
 
+	display->reset.count++;
 	display->restore.modeset_state = state;
 	state->acquire_ctx = ctx;
 }
@@ -114,3 +117,10 @@ void intel_display_reset_finish(struct intel_display *display, bool test_only)
 	drm_modeset_acquire_fini(ctx);
 	mutex_unlock(&display->drm->mode_config.mutex);
 }
+
+void intel_display_reset_debugfs_register(struct intel_display *display)
+{
+	debugfs_create_u32("display_reset_count", 0400,
+			   display->drm->debugfs_root,
+			   &display->reset.count);
+}
diff --git a/drivers/gpu/drm/i915/display/intel_display_reset.h b/drivers/gpu/drm/i915/display/intel_display_reset.h
index a8aa7729d33f..b88c330a3441 100644
--- a/drivers/gpu/drm/i915/display/intel_display_reset.h
+++ b/drivers/gpu/drm/i915/display/intel_display_reset.h
@@ -15,4 +15,6 @@ bool intel_display_reset_test(struct intel_display *display);
 void intel_display_reset_prepare(struct intel_display *display);
 void intel_display_reset_finish(struct intel_display *display, bool test_only);
 
+void intel_display_reset_debugfs_register(struct intel_display *display);
+
 #endif /* __INTEL_RESET_H__ */
diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
index 110fef511fe2..1a85dfe457f0 100644
--- a/drivers/gpu/drm/xe/Makefile
+++ b/drivers/gpu/drm/xe/Makefile
@@ -262,6 +262,7 @@ xe-$(CONFIG_DRM_XE_DISPLAY) += \
 	i915-display/intel_display_power.o \
 	i915-display/intel_display_power_map.o \
 	i915-display/intel_display_power_well.o \
+	i915-display/intel_display_reset.o \
 	i915-display/intel_display_rpm.o \
 	i915-display/intel_display_rps.o \
 	i915-display/intel_display_trace.o \
-- 
2.52.0