+Jouni
On 4/3/2024 1:22 PM, Balasubramani Vivekanandan wrote:
From: Matthew Auld <matthew.auld@xxxxxxxxx>
Perform manual transient cache flush prior to flip and at the end of
frontbuffer_flush. This is needed to ensure display engine doesn't see
garbage if the surface is L3:XD dirty.
Testcase: igt@xe-pat@display-vs-wb-transient
Signed-off-by: Matthew Auld <matthew.auld@xxxxxxxxx>
Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@xxxxxxxxx>
Acked-by: Nirmoy Das <nirmoy.das@xxxxxxxxx>
---
drivers/gpu/drm/i915/display/intel_display.c | 3 +++
.../gpu/drm/i915/display/intel_frontbuffer.c | 2 ++
drivers/gpu/drm/i915/display/intel_tdf.h | 25 +++++++++++++++++++
drivers/gpu/drm/xe/Makefile | 3 ++-
drivers/gpu/drm/xe/display/xe_tdf.c | 13 ++++++++++
5 files changed, 45 insertions(+), 1 deletion(-)
create mode 100644 drivers/gpu/drm/i915/display/intel_tdf.h
create mode 100644 drivers/gpu/drm/xe/display/xe_tdf.c
diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index aed25890b6f5..0a720e9d12a7 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -110,6 +110,7 @@
#include "intel_sdvo.h"
#include "intel_snps_phy.h"
#include "intel_tc.h"
+#include "intel_tdf.h"
#include "intel_tv.h"
#include "intel_vblank.h"
#include "intel_vdsc.h"
@@ -7095,6 +7096,8 @@ static void intel_atomic_commit_tail(struct intel_atomic_state *state)
intel_atomic_commit_fence_wait(state);
+ intel_td_flush(dev_priv);
+
drm_atomic_helper_wait_for_dependencies(&state->base);
drm_dp_mst_atomic_wait_for_dependencies(&state->base);
intel_atomic_global_state_wait_for_dependencies(state);
diff --git a/drivers/gpu/drm/i915/display/intel_frontbuffer.c b/drivers/gpu/drm/i915/display/intel_frontbuffer.c
index 2ea37c0414a9..4923c340a0b6 100644
--- a/drivers/gpu/drm/i915/display/intel_frontbuffer.c
+++ b/drivers/gpu/drm/i915/display/intel_frontbuffer.c
@@ -65,6 +65,7 @@
#include "intel_fbc.h"
#include "intel_frontbuffer.h"
#include "intel_psr.h"
+#include "intel_tdf.h"
/**
* frontbuffer_flush - flush frontbuffer
@@ -93,6 +94,7 @@ static void frontbuffer_flush(struct drm_i915_private *i915,
trace_intel_frontbuffer_flush(i915, frontbuffer_bits, origin);
might_sleep();
+ intel_td_flush(i915);
intel_drrs_flush(i915, frontbuffer_bits);
intel_psr_flush(i915, frontbuffer_bits, origin);
intel_fbc_flush(i915, frontbuffer_bits, origin);
diff --git a/drivers/gpu/drm/i915/display/intel_tdf.h b/drivers/gpu/drm/i915/display/intel_tdf.h
new file mode 100644
index 000000000000..353cde21f6c2
--- /dev/null
+++ b/drivers/gpu/drm/i915/display/intel_tdf.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2024 Intel Corporation
+ */
+
+#ifndef __INTEL_TDF_H__
+#define __INTEL_TDF_H__
+
+/*
+ * TDF (Transient-Data-Flush) is needed for Xe2+ where special L3:XD caching can
+ * be enabled through various PAT index modes. Idea is to use this caching mode
+ * when for example rendering onto the display surface, with the promise that
+ * KMD will ensure transient cache entries are always flushed by the time we do
+ * the display flip, since display engine is never coherent with CPU/GPU caches.
+ */
+
+struct drm_i915_private;
+
+#ifdef I915
+static inline void intel_td_flush(struct drm_i915_private *i915) {}
+#else
+void intel_td_flush(struct drm_i915_private *i915);
+#endif
+
+#endif
diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
index e5b1715f721e..401a4492c625 100644
--- a/drivers/gpu/drm/xe/Makefile
+++ b/drivers/gpu/drm/xe/Makefile
@@ -196,7 +196,8 @@ xe-$(CONFIG_DRM_XE_DISPLAY) += \
display/xe_dsb_buffer.o \
display/xe_fb_pin.o \
display/xe_hdcp_gsc.o \
- display/xe_plane_initial.o
+ display/xe_plane_initial.o \
+ display/xe_tdf.o
# SOC code shared with i915
xe-$(CONFIG_DRM_XE_DISPLAY) += \
diff --git a/drivers/gpu/drm/xe/display/xe_tdf.c b/drivers/gpu/drm/xe/display/xe_tdf.c
new file mode 100644
index 000000000000..2c0d4e144e09
--- /dev/null
+++ b/drivers/gpu/drm/xe/display/xe_tdf.c
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2024 Intel Corporation
+ */
+
+#include "xe_device.h"
+#include "intel_display_types.h"
+#include "intel_tdf.h"
+
+void intel_td_flush(struct drm_i915_private *i915)
+{
+ xe_device_td_flush(i915);
+}