[Intel-gfx] [PATCH v2 12/12] drm/i915: Implement transcoder LRR for TGL+
Ville Syrjala
ville.syrjala at linux.intel.com
Fri Sep 15 10:38:00 UTC 2023
From: Ville Syrjälä <ville.syrjala at linux.intel.com>
Implement low refresh rate (LRR) where we change the vblank
length by hand as requested, but otherwise keep the timing
generator running in non-VRR mode (ie. fixed refresh rate).
The panel itself must support VRR for this to work, and
only TGL+ has the double buffred TRANS_VTOTAL.VTOTAL that
we need to make the switch properly. The double buffer
latching happens at the start of transcoders undelayed
vblank. The other thing that we change is
TRANS_VBLANK.VBLANK_END but the hardware entirely ignores
that in DP mode. But I decided to keep writing it anyway
just to avoid more special cases in readout/state check.
v2: Document that TRANS_VBLANK.VBLANK_END is ignored by
the hardware
v3: Reconcile with VRR fastset
Adjust update_lrr flag behaviour
Make sure timings stay within VRR range
v4: Fix up update_m_n vs. update_lrr rebase fail (Manasi)
Drop DOUBLE_BUFFER_VACTIVE define as it's not needed (Manasi)
TODO: Hook LRR into the automatic DRRS downclocking stuff?
Cc: Manasi Navare <navaremanasi at chromium.org>
Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
drivers/gpu/drm/i915/display/intel_atomic.c | 1 +
drivers/gpu/drm/i915/display/intel_crtc.c | 9 +--
drivers/gpu/drm/i915/display/intel_display.c | 60 +++++++++++++++++--
.../drm/i915/display/intel_display_device.h | 1 +
.../drm/i915/display/intel_display_types.h | 3 +-
drivers/gpu/drm/i915/display/intel_vrr.c | 7 ++-
6 files changed, 70 insertions(+), 11 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_atomic.c b/drivers/gpu/drm/i915/display/intel_atomic.c
index aaddd8c0cfa0..5d18145da279 100644
--- a/drivers/gpu/drm/i915/display/intel_atomic.c
+++ b/drivers/gpu/drm/i915/display/intel_atomic.c
@@ -260,6 +260,7 @@ intel_crtc_duplicate_state(struct drm_crtc *crtc)
crtc_state->update_pipe = false;
crtc_state->update_m_n = false;
+ crtc_state->update_lrr = false;
crtc_state->disable_lp_wm = false;
crtc_state->disable_cxsr = false;
crtc_state->update_wm_pre = false;
diff --git a/drivers/gpu/drm/i915/display/intel_crtc.c b/drivers/gpu/drm/i915/display/intel_crtc.c
index a39e31c1ca85..22e85fe7e8aa 100644
--- a/drivers/gpu/drm/i915/display/intel_crtc.c
+++ b/drivers/gpu/drm/i915/display/intel_crtc.c
@@ -495,7 +495,7 @@ static void intel_crtc_vblank_evade_scanlines(struct intel_atomic_state *state,
if (crtc->mode_flags & I915_MODE_FLAG_VRR) {
/* timing changes should happen with VRR disabled */
drm_WARN_ON(state->base.dev, intel_crtc_needs_modeset(new_crtc_state) ||
- new_crtc_state->update_m_n);
+ new_crtc_state->update_m_n || new_crtc_state->update_lrr);
if (intel_vrr_is_push_sent(crtc_state))
*vblank_start = intel_vrr_vmin_vblank_start(crtc_state);
@@ -511,10 +511,11 @@ static void intel_crtc_vblank_evade_scanlines(struct intel_atomic_state *state,
*max = *vblank_start - 1;
/*
- * M/N is double buffered on the transcoder's undelayed vblank,
- * so with seamless M/N we must evade both vblanks.
+ * M/N and TRANS_VTOTAL are double buffered on the transcoder's
+ * undelayed vblank, so with seamless M/N and LRR we must evade
+ * both vblanks.
*/
- if (new_crtc_state->update_m_n)
+ if (new_crtc_state->update_m_n || new_crtc_state->update_lrr)
*min -= adjusted_mode->crtc_vblank_start - adjusted_mode->crtc_vdisplay;
}
diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index f0bb5c70ebfc..988558ccf794 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -928,7 +928,7 @@ static bool vrr_enabling(const struct intel_crtc_state *old_crtc_state,
{
return is_enabling(vrr.enable, old_crtc_state, new_crtc_state) ||
(new_crtc_state->vrr.enable &&
- (new_crtc_state->update_m_n ||
+ (new_crtc_state->update_m_n || new_crtc_state->update_lrr ||
vrr_params_changed(old_crtc_state, new_crtc_state)));
}
@@ -937,7 +937,7 @@ static bool vrr_disabling(const struct intel_crtc_state *old_crtc_state,
{
return is_disabling(vrr.enable, old_crtc_state, new_crtc_state) ||
(old_crtc_state->vrr.enable &&
- (new_crtc_state->update_m_n ||
+ (new_crtc_state->update_m_n || new_crtc_state->update_lrr ||
vrr_params_changed(old_crtc_state, new_crtc_state)));
}
@@ -2586,6 +2586,37 @@ static void intel_set_transcoder_timings(const struct intel_crtc_state *crtc_sta
VTOTAL(crtc_vtotal - 1));
}
+static void intel_set_transcoder_timings_lrr(const struct intel_crtc_state *crtc_state)
+{
+ struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
+ struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+ enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
+ const struct drm_display_mode *adjusted_mode = &crtc_state->hw.adjusted_mode;
+ u32 crtc_vdisplay, crtc_vtotal, crtc_vblank_start, crtc_vblank_end;
+
+ crtc_vdisplay = adjusted_mode->crtc_vdisplay;
+ crtc_vtotal = adjusted_mode->crtc_vtotal;
+ crtc_vblank_start = adjusted_mode->crtc_vblank_start;
+ crtc_vblank_end = adjusted_mode->crtc_vblank_end;
+
+ drm_WARN_ON(&dev_priv->drm, adjusted_mode->flags & DRM_MODE_FLAG_INTERLACE);
+
+ /*
+ * The hardware actually ignores TRANS_VBLANK.VBLANK_END in DP mode.
+ * But let's write it anyway to keep the state checker happy.
+ */
+ intel_de_write(dev_priv, TRANS_VBLANK(cpu_transcoder),
+ VBLANK_START(crtc_vblank_start - 1) |
+ VBLANK_END(crtc_vblank_end - 1));
+ /*
+ * The double buffer latch point for TRANS_VTOTAL
+ * is the transcoder's undelayed vblank.
+ */
+ intel_de_write(dev_priv, TRANS_VTOTAL(cpu_transcoder),
+ VACTIVE(crtc_vdisplay - 1) |
+ VTOTAL(crtc_vtotal - 1));
+}
+
static void intel_set_pipe_src_size(const struct intel_crtc_state *crtc_state)
{
struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
@@ -5082,11 +5113,13 @@ intel_pipe_config_compare(const struct intel_crtc_state *current_config,
PIPE_CONF_CHECK_I(name.crtc_hsync_start); \
PIPE_CONF_CHECK_I(name.crtc_hsync_end); \
PIPE_CONF_CHECK_I(name.crtc_vdisplay); \
- PIPE_CONF_CHECK_I(name.crtc_vtotal); \
PIPE_CONF_CHECK_I(name.crtc_vblank_start); \
- PIPE_CONF_CHECK_I(name.crtc_vblank_end); \
PIPE_CONF_CHECK_I(name.crtc_vsync_start); \
PIPE_CONF_CHECK_I(name.crtc_vsync_end); \
+ if (!fastset || !pipe_config->update_lrr) { \
+ PIPE_CONF_CHECK_I(name.crtc_vtotal); \
+ PIPE_CONF_CHECK_I(name.crtc_vblank_end); \
+ } \
} while (0)
#define PIPE_CONF_CHECK_RECT(name) do { \
@@ -5420,6 +5453,7 @@ int intel_modeset_all_pipes(struct intel_atomic_state *state,
crtc_state->uapi.mode_changed = true;
crtc_state->update_pipe = false;
crtc_state->update_m_n = false;
+ crtc_state->update_lrr = false;
ret = drm_atomic_add_affected_connectors(&state->base,
&crtc->base);
@@ -5537,6 +5571,10 @@ static void intel_crtc_check_fastset(const struct intel_crtc_state *old_crtc_sta
{
struct drm_i915_private *i915 = to_i915(old_crtc_state->uapi.crtc->dev);
+ /* only allow LRR when the timings stay within the VRR range */
+ if (old_crtc_state->vrr.in_range != new_crtc_state->vrr.in_range)
+ new_crtc_state->update_lrr = false;
+
if (!intel_pipe_config_compare(old_crtc_state, new_crtc_state, true))
drm_dbg_kms(&i915->drm, "fastset requirement not met, forcing full modeset\n");
else
@@ -5547,6 +5585,11 @@ static void intel_crtc_check_fastset(const struct intel_crtc_state *old_crtc_sta
&new_crtc_state->dp_m_n))
new_crtc_state->update_m_n = false;
+ if (intel_crtc_needs_modeset(new_crtc_state) ||
+ (old_crtc_state->hw.adjusted_mode.crtc_vtotal == new_crtc_state->hw.adjusted_mode.crtc_vtotal &&
+ old_crtc_state->hw.adjusted_mode.crtc_vblank_end == new_crtc_state->hw.adjusted_mode.crtc_vblank_end))
+ new_crtc_state->update_lrr = false;
+
if (!intel_crtc_needs_modeset(new_crtc_state))
new_crtc_state->update_pipe = true;
}
@@ -6262,6 +6305,7 @@ int intel_atomic_check(struct drm_device *dev,
new_crtc_state->uapi.mode_changed = true;
new_crtc_state->update_pipe = false;
new_crtc_state->update_m_n = false;
+ new_crtc_state->update_lrr = false;
}
}
@@ -6275,6 +6319,7 @@ int intel_atomic_check(struct drm_device *dev,
new_crtc_state->uapi.mode_changed = true;
new_crtc_state->update_pipe = false;
new_crtc_state->update_m_n = false;
+ new_crtc_state->update_lrr = false;
}
}
@@ -6283,6 +6328,7 @@ int intel_atomic_check(struct drm_device *dev,
new_crtc_state->uapi.mode_changed = true;
new_crtc_state->update_pipe = false;
new_crtc_state->update_m_n = false;
+ new_crtc_state->update_lrr = false;
}
}
}
@@ -6464,6 +6510,9 @@ static void intel_pipe_fastset(const struct intel_crtc_state *old_crtc_state,
if (new_crtc_state->update_m_n)
intel_cpu_transcoder_set_m1_n1(crtc, new_crtc_state->cpu_transcoder,
&new_crtc_state->dp_m_n);
+
+ if (new_crtc_state->update_lrr)
+ intel_set_transcoder_timings_lrr(new_crtc_state);
}
static void commit_pipe_pre_planes(struct intel_atomic_state *state,
@@ -6600,7 +6649,8 @@ static void intel_update_crtc(struct intel_atomic_state *state,
*
* FIXME Should be synchronized with the start of vblank somehow...
*/
- if (vrr_enabling(old_crtc_state, new_crtc_state) || new_crtc_state->update_m_n)
+ if (vrr_enabling(old_crtc_state, new_crtc_state) ||
+ new_crtc_state->update_m_n || new_crtc_state->update_lrr)
intel_crtc_update_active_timings(new_crtc_state,
new_crtc_state->vrr.enable);
diff --git a/drivers/gpu/drm/i915/display/intel_display_device.h b/drivers/gpu/drm/i915/display/intel_display_device.h
index 8198401aa5be..ee77750af82b 100644
--- a/drivers/gpu/drm/i915/display/intel_display_device.h
+++ b/drivers/gpu/drm/i915/display/intel_display_device.h
@@ -56,6 +56,7 @@ struct drm_printer;
#define HAS_HW_SAGV_WM(i915) (DISPLAY_VER(i915) >= 13 && !IS_DGFX(i915))
#define HAS_IPC(i915) (DISPLAY_INFO(i915)->has_ipc)
#define HAS_IPS(i915) (IS_HASWELL_ULT(i915) || IS_BROADWELL(i915))
+#define HAS_LRR(i915) (DISPLAY_VER(i915) >= 12)
#define HAS_LSPCON(i915) (IS_DISPLAY_VER(i915, 9, 10))
#define HAS_MBUS_JOINING(i915) (IS_ALDERLAKE_P(i915) || DISPLAY_VER(i915) >= 14)
#define HAS_MSO(i915) (DISPLAY_VER(i915) >= 12)
diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index 2f35560d7e4e..536c642eb562 100644
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -1084,6 +1084,7 @@ struct intel_crtc_state {
unsigned fb_bits; /* framebuffers to flip */
bool update_pipe; /* can a fast modeset be performed? */
bool update_m_n; /* update M/N seamlessly during fastset? */
+ bool update_lrr; /* update TRANS_VTOTAL/etc. during fastset? */
bool disable_cxsr;
bool update_wm_pre, update_wm_post; /* watermarks are updated */
bool fifo_changed; /* FIFO split is changed */
@@ -1383,7 +1384,7 @@ struct intel_crtc_state {
/* Variable Refresh Rate state */
struct {
- bool enable;
+ bool enable, in_range;
u8 pipeline_full;
u16 flipline, vmin, vmax, guardband;
} vrr;
diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
index 12731ad725a8..5d905f932cb4 100644
--- a/drivers/gpu/drm/i915/display/intel_vrr.c
+++ b/drivers/gpu/drm/i915/display/intel_vrr.c
@@ -120,9 +120,14 @@ intel_vrr_compute_config(struct intel_crtc_state *crtc_state,
if (adjusted_mode->flags & DRM_MODE_FLAG_INTERLACE)
return;
- if (!intel_vrr_is_in_range(connector, drm_mode_vrefresh(adjusted_mode)))
+ crtc_state->vrr.in_range =
+ intel_vrr_is_in_range(connector, drm_mode_vrefresh(adjusted_mode));
+ if (!crtc_state->vrr.in_range)
return;
+ if (HAS_LRR(i915))
+ crtc_state->update_lrr = true;
+
vmin = DIV_ROUND_UP(adjusted_mode->crtc_clock * 1000,
adjusted_mode->crtc_htotal * info->monitor_range.max_vfreq);
vmax = adjusted_mode->crtc_clock * 1000 /
--
2.41.0
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