[PATCH 2/2] drm/i915/lnl: Program PKGC_LATENCY register
Suraj Kandpal
suraj.kandpal at intel.com
Tue Feb 13 06:28:54 UTC 2024
If fixed refresh rate program the PKGC_LATENCY register
with the highest latency from level 1 and above LP registers
and program ADDED_WAKE_TIME = DSB execution time.
else program PKGC_LATENCY with all 1's and ADDED_WAKE_TIME as 0.
This is used to improve package C residency by sending the highest
latency tolerance requirement (LTR) when the planes are done with the
frame until the next frame programming window (set context latency,
window 2) starts.
Bspec: 68986
--v2
-Fix indentation [Chaitanya]
--v3
-Take into account if fixed refrersh rate or not [Vinod]
-Added wake time dependengt on DSB execution time [Vinod]
-Use REG_FIELD_PREP [Jani]
-Call program_pkgc_latency from appropriate place [Jani]
-no need for the ~0 while setting max latency [Jani]
-change commit message to add the new changes made in.
Signed-off-by: Suraj Kandpal <suraj.kandpal at intel.com>
Reviewed-by: Chaitanya Kumar Borah <chaitanya.kumar.borah at intel.com>
---
drivers/gpu/drm/i915/display/intel_dsb.c | 2 +-
drivers/gpu/drm/i915/display/skl_watermark.c | 59 +++++++++++++++++++-
drivers/gpu/drm/i915/display/skl_watermark.h | 4 +-
3 files changed, 60 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c b/drivers/gpu/drm/i915/display/intel_dsb.c
index a6c7122fd671..d62e050185e7 100644
--- a/drivers/gpu/drm/i915/display/intel_dsb.c
+++ b/drivers/gpu/drm/i915/display/intel_dsb.c
@@ -325,7 +325,7 @@ static int intel_dsb_dewake_scanline(const struct intel_crtc_state *crtc_state)
{
struct drm_i915_private *i915 = to_i915(crtc_state->uapi.crtc->dev);
const struct drm_display_mode *adjusted_mode = &crtc_state->hw.adjusted_mode;
- unsigned int latency = skl_watermark_max_latency(i915);
+ unsigned int latency = skl_watermark_max_latency(i915, 0);
int vblank_start;
if (crtc_state->vrr.enable) {
diff --git a/drivers/gpu/drm/i915/display/skl_watermark.c b/drivers/gpu/drm/i915/display/skl_watermark.c
index 614f319d754e..1d423ce0f42d 100644
--- a/drivers/gpu/drm/i915/display/skl_watermark.c
+++ b/drivers/gpu/drm/i915/display/skl_watermark.c
@@ -23,6 +23,12 @@
#include "skl_watermark.h"
#include "skl_watermark_regs.h"
+/*It is expected that DSB can do posted writes to every register in
+ * the pipe and planes within 100us. For flip queue use case, the
+ * recommended DSB execution time is 100us + one SAGV block time.
+ */
+#define DSB_EXE_TIME 100
+
static void skl_sagv_disable(struct drm_i915_private *i915);
/* Stores plane specific WM parameters */
@@ -2904,12 +2910,51 @@ static int skl_wm_add_affected_planes(struct intel_atomic_state *state,
return 0;
}
+/*
+ * If Fixed Refresh Rate:
+ * Program DEEP PKG_C_LATENCY Pkg C with highest valid latency from
+ * watermark level1 and up and above. If watermark level 1 is
+ * invalid program it with all 1's.
+ * Program PKG_C_LATENCY Added Wake Time = DSB execution time
+ * If Variable Refresh Rate:
+ * Program DEEP PKG_C_LATENCY Pkg C with all 1's.
+ * Program PKG_C_LATENCY Added Wake Time = 0
+ */
+static void
+skl_program_dpkgc_latency(struct drm_i915_private *i915, bool vrr_enabled)
+{
+ u32 max_latency = 0;
+ u32 clear = 0, val = 0;
+ u32 added_wake_time = 0;
+
+ if (DISPLAY_VER(i915) < 20)
+ return;
+
+ if (vrr_enabled) {
+ max_latency = LNL_PKG_C_LATENCY_MASK;
+ added_wake_time = 0;
+ } else {
+ max_latency = skl_watermark_max_latency(i915, 1);
+ if (max_latency == 0)
+ max_latency = LNL_PKG_C_LATENCY_MASK;
+ added_wake_time = DSB_EXE_TIME +
+ i915->display.sagv.block_time_us;
+ }
+
+ clear |= LNL_ADDED_WAKE_TIME_MASK | LNL_PKG_C_LATENCY_MASK;
+ val |= REG_FIELD_PREP(LNL_PKG_C_LATENCY_MASK, max_latency);
+ val |= REG_FIELD_PREP(LNL_ADDED_WAKE_TIME_MASK, added_wake_time);
+
+ intel_uncore_rmw(&i915->uncore, LNL_PKG_C_LATENCY, clear, val);
+}
+
static int
skl_compute_wm(struct intel_atomic_state *state)
{
struct intel_crtc *crtc;
struct intel_crtc_state __maybe_unused *new_crtc_state;
int ret, i;
+ bool vrr_enabled = false;
for_each_new_intel_crtc_in_state(state, crtc, new_crtc_state, i) {
ret = skl_build_pipe_wm(state, crtc);
@@ -2936,6 +2981,15 @@ skl_compute_wm(struct intel_atomic_state *state)
return ret;
}
+ for_each_new_intel_crtc_in_state(state, crtc, new_crtc_state, i) {
+ if (new_crtc_state->vrr.enable) {
+ vrr_enabled = true;
+ break;
+ }
+ }
+
+ skl_program_dpkgc_latency(to_i915(state->base.dev), vrr_enabled);
+
skl_print_wm_changes(state);
return 0;
@@ -3415,6 +3469,7 @@ static void skl_setup_wm_latency(struct drm_i915_private *i915)
skl_read_wm_latency(i915, i915->display.wm.skl_latency);
intel_print_wm_latency(i915, "Gen9 Plane", i915->display.wm.skl_latency);
+
}
static const struct intel_wm_funcs skl_wm_funcs = {
@@ -3731,11 +3786,11 @@ void skl_watermark_debugfs_register(struct drm_i915_private *i915)
&intel_sagv_status_fops);
}
-unsigned int skl_watermark_max_latency(struct drm_i915_private *i915)
+unsigned int skl_watermark_max_latency(struct drm_i915_private *i915, int initial_wm_level)
{
int level;
- for (level = i915->display.wm.num_levels - 1; level >= 0; level--) {
+ for (level = i915->display.wm.num_levels - 1; level >= initial_wm_level; level--) {
unsigned int latency = skl_wm_latency(i915, level, NULL);
if (latency)
diff --git a/drivers/gpu/drm/i915/display/skl_watermark.h b/drivers/gpu/drm/i915/display/skl_watermark.h
index fb0da36fd3ec..e3d1d74a7b17 100644
--- a/drivers/gpu/drm/i915/display/skl_watermark.h
+++ b/drivers/gpu/drm/i915/display/skl_watermark.h
@@ -46,8 +46,8 @@ void skl_watermark_ipc_update(struct drm_i915_private *i915);
bool skl_watermark_ipc_enabled(struct drm_i915_private *i915);
void skl_watermark_debugfs_register(struct drm_i915_private *i915);
-unsigned int skl_watermark_max_latency(struct drm_i915_private *i915);
-
+unsigned int skl_watermark_max_latency(struct drm_i915_private *i915,
+ int initial_wm_level);
void skl_wm_init(struct drm_i915_private *i915);
struct intel_dbuf_state {
--
2.25.1
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