[Intel-gfx] [PATCH v3 10/25] drm/i915/fdi: Improve FDI BW sharing between pipe B and C
Imre Deak
imre.deak at intel.com
Thu Sep 14 19:26:44 UTC 2023
At the moment modesetting pipe C on IVB will fail if pipe B uses 4 FDI
lanes. Make the BW sharing more dynamic by trying to reduce pipe B's
link bpp in this case, until pipe B uses only up to 2 FDI lanes.
For this instead of the encoder compute config retry loop - which
reduced link bpp only for the encoder's pipe - reduce the maximum link
bpp for pipe B/C as required after all CRTC states are computed and
recompute the CRTC states with the new bpp limit.
v2:
- Don't assume that a CRTC is already in the atomic state, while
reducing its link bpp.
- Add DocBook description to intel_fdi_atomic_check_link().
v3:
- Enable BW management for FDI links in a separate patch. (Ville)
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: Imre Deak <imre.deak at intel.com>
---
drivers/gpu/drm/i915/display/g4x_hdmi.c | 6 +-
drivers/gpu/drm/i915/display/intel_crt.c | 7 ++
drivers/gpu/drm/i915/display/intel_display.c | 14 +---
drivers/gpu/drm/i915/display/intel_dp.c | 3 +-
drivers/gpu/drm/i915/display/intel_fdi.c | 87 +++++++++++++++-----
drivers/gpu/drm/i915/display/intel_fdi.h | 4 +
drivers/gpu/drm/i915/display/intel_link_bw.c | 7 +-
drivers/gpu/drm/i915/display/intel_lvds.c | 10 ++-
drivers/gpu/drm/i915/display/intel_sdvo.c | 10 ++-
9 files changed, 107 insertions(+), 41 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/g4x_hdmi.c b/drivers/gpu/drm/i915/display/g4x_hdmi.c
index 634b14116d9dd..8b5d26cd3b85e 100644
--- a/drivers/gpu/drm/i915/display/g4x_hdmi.c
+++ b/drivers/gpu/drm/i915/display/g4x_hdmi.c
@@ -19,6 +19,7 @@
#include "intel_fifo_underrun.h"
#include "intel_hdmi.h"
#include "intel_hotplug.h"
+#include "intel_link_bw.h"
#include "intel_sdvo.h"
#include "vlv_sideband.h"
@@ -133,8 +134,11 @@ static int g4x_hdmi_compute_config(struct intel_encoder *encoder,
struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
struct drm_i915_private *i915 = to_i915(encoder->base.dev);
- if (HAS_PCH_SPLIT(i915))
+ if (HAS_PCH_SPLIT(i915)) {
crtc_state->has_pch_encoder = true;
+ if (!intel_link_bw_compute_pipe_bpp(crtc_state))
+ return -EINVAL;
+ }
if (IS_G4X(i915))
crtc_state->has_hdmi_sink = g4x_compute_has_hdmi_sink(state, crtc);
diff --git a/drivers/gpu/drm/i915/display/intel_crt.c b/drivers/gpu/drm/i915/display/intel_crt.c
index f6df6c4fa72ef..7aa89d0fa3d6c 100644
--- a/drivers/gpu/drm/i915/display/intel_crt.c
+++ b/drivers/gpu/drm/i915/display/intel_crt.c
@@ -49,6 +49,7 @@
#include "intel_gmbus.h"
#include "intel_hotplug.h"
#include "intel_hotplug_irq.h"
+#include "intel_link_bw.h"
#include "intel_load_detect.h"
#include "intel_pch_display.h"
#include "intel_pch_refclk.h"
@@ -413,6 +414,9 @@ static int pch_crt_compute_config(struct intel_encoder *encoder,
return -EINVAL;
pipe_config->has_pch_encoder = true;
+ if (!intel_link_bw_compute_pipe_bpp(pipe_config))
+ return -EINVAL;
+
pipe_config->output_format = INTEL_OUTPUT_FORMAT_RGB;
return 0;
@@ -435,6 +439,9 @@ static int hsw_crt_compute_config(struct intel_encoder *encoder,
return -EINVAL;
pipe_config->has_pch_encoder = true;
+ if (!intel_link_bw_compute_pipe_bpp(pipe_config))
+ return -EINVAL;
+
pipe_config->output_format = INTEL_OUTPUT_FORMAT_RGB;
/* LPT FDI RX only supports 8bpc. */
diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 29816153fdd59..aad16dcceb788 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -4607,7 +4607,6 @@ intel_modeset_pipe_config(struct intel_atomic_state *state,
struct drm_connector_state *connector_state;
int pipe_src_w, pipe_src_h;
int base_bpp, ret, i;
- bool retry = true;
crtc_state->cpu_transcoder = (enum transcoder) crtc->pipe;
@@ -4637,6 +4636,7 @@ intel_modeset_pipe_config(struct intel_atomic_state *state,
"[CRTC:%d:%s] Link bpp limited to " BPP_X16_FMT "\n",
crtc->base.base.id, crtc->base.name,
BPP_X16_ARGS(crtc_state->max_link_bpp_x16));
+ crtc_state->bw_constrained = true;
}
base_bpp = crtc_state->pipe_bpp;
@@ -4680,7 +4680,6 @@ intel_modeset_pipe_config(struct intel_atomic_state *state,
crtc_state->output_types |= BIT(encoder->type);
}
-encoder_retry:
/* Ensure the port clock defaults are reset when retrying. */
crtc_state->port_clock = 0;
crtc_state->pixel_multiplier = 1;
@@ -4720,17 +4719,6 @@ intel_modeset_pipe_config(struct intel_atomic_state *state,
ret = intel_crtc_compute_config(state, crtc);
if (ret == -EDEADLK)
return ret;
- if (ret == -EAGAIN) {
- if (drm_WARN(&i915->drm, !retry,
- "[CRTC:%d:%s] loop in pipe configuration computation\n",
- crtc->base.base.id, crtc->base.name))
- return -EINVAL;
-
- drm_dbg_kms(&i915->drm, "[CRTC:%d:%s] bw constrained, retrying\n",
- crtc->base.base.id, crtc->base.name);
- retry = false;
- goto encoder_retry;
- }
if (ret < 0) {
drm_dbg_kms(&i915->drm, "[CRTC:%d:%s] config failure: %d\n",
crtc->base.base.id, crtc->base.name, ret);
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index d5e6813d36c8f..03010accc1c7f 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -2219,7 +2219,8 @@ intel_dp_compute_config_link_bpp_limits(struct intel_dp *intel_dp,
const struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
int max_link_bpp_x16;
- max_link_bpp_x16 = to_bpp_x16(limits->pipe.max_bpp);
+ max_link_bpp_x16 = min(crtc_state->max_link_bpp_x16,
+ to_bpp_x16(limits->pipe.max_bpp));
if (!dsc) {
max_link_bpp_x16 = rounddown(max_link_bpp_x16, to_bpp_x16(2 * 3));
diff --git a/drivers/gpu/drm/i915/display/intel_fdi.c b/drivers/gpu/drm/i915/display/intel_fdi.c
index 4d7d524c68017..ad01915a4a39b 100644
--- a/drivers/gpu/drm/i915/display/intel_fdi.c
+++ b/drivers/gpu/drm/i915/display/intel_fdi.c
@@ -13,6 +13,7 @@
#include "intel_display_types.h"
#include "intel_fdi.h"
#include "intel_fdi_regs.h"
+#include "intel_link_bw.h"
struct intel_fdi_funcs {
void (*fdi_link_train)(struct intel_crtc *crtc,
@@ -129,13 +130,16 @@ static int pipe_required_fdi_lanes(struct intel_crtc_state *crtc_state)
}
static int ilk_check_fdi_lanes(struct drm_device *dev, enum pipe pipe,
- struct intel_crtc_state *pipe_config)
+ struct intel_crtc_state *pipe_config,
+ enum pipe *pipe_to_reduce)
{
struct drm_i915_private *dev_priv = to_i915(dev);
struct drm_atomic_state *state = pipe_config->uapi.state;
struct intel_crtc *other_crtc;
struct intel_crtc_state *other_crtc_state;
+ *pipe_to_reduce = pipe;
+
drm_dbg_kms(&dev_priv->drm,
"checking fdi config on pipe %c, lanes %i\n",
pipe_name(pipe), pipe_config->fdi_lanes);
@@ -198,6 +202,9 @@ static int ilk_check_fdi_lanes(struct drm_device *dev, enum pipe pipe,
if (pipe_required_fdi_lanes(other_crtc_state) > 2) {
drm_dbg_kms(&dev_priv->drm,
"fdi link B uses too many lanes to enable link C\n");
+
+ *pipe_to_reduce = PIPE_B;
+
return -EINVAL;
}
return 0;
@@ -238,10 +245,8 @@ int ilk_fdi_compute_config(struct intel_crtc *crtc,
struct drm_device *dev = crtc->base.dev;
struct drm_i915_private *i915 = to_i915(dev);
const struct drm_display_mode *adjusted_mode = &pipe_config->hw.adjusted_mode;
- int lane, link_bw, fdi_dotclock, ret;
- bool needs_recompute = false;
+ int lane, link_bw, fdi_dotclock;
-retry:
/* FDI is a binary signal running at ~2.7GHz, encoding
* each output octet as 10 bits. The actual frequency
* is stored as a divider into a 100MHz clock, and the
@@ -261,25 +266,69 @@ int ilk_fdi_compute_config(struct intel_crtc *crtc,
intel_link_compute_m_n(pipe_config->pipe_bpp, lane, fdi_dotclock,
link_bw, &pipe_config->fdi_m_n, false);
- ret = ilk_check_fdi_lanes(dev, crtc->pipe, pipe_config);
- if (ret == -EDEADLK)
+ return 0;
+}
+
+static int intel_fdi_atomic_check_bw(struct intel_atomic_state *state,
+ struct intel_crtc *crtc,
+ struct intel_crtc_state *pipe_config,
+ struct intel_link_bw_limits *limits)
+{
+ struct drm_i915_private *i915 = to_i915(crtc->base.dev);
+ enum pipe pipe_to_reduce;
+ int ret;
+
+ ret = ilk_check_fdi_lanes(&i915->drm, crtc->pipe, pipe_config,
+ &pipe_to_reduce);
+ if (ret != -EINVAL)
return ret;
- if (ret == -EINVAL && pipe_config->pipe_bpp > 6*3) {
- pipe_config->pipe_bpp -= 2*3;
- drm_dbg_kms(&i915->drm,
- "fdi link bw constraint, reducing pipe bpp to %i\n",
- pipe_config->pipe_bpp);
- needs_recompute = true;
- pipe_config->bw_constrained = true;
-
- goto retry;
+ ret = intel_link_bw_reduce_bpp(state, limits,
+ BIT(pipe_to_reduce),
+ "FDI link BW");
+
+ return ret ? : -EAGAIN;
+}
+
+/**
+ * intel_fdi_atomic_check_link - check all modeset FDI link configuration
+ * @state: intel atomic state
+ * @limits: link BW limits
+ *
+ * Check the link configuration for all modeset FDI outputs. If the
+ * configuration is invalid @limits will be updated if possible to
+ * reduce the total BW, after which the configuration for all CRTCs in
+ * @state must be recomputed with the updated @limits.
+ *
+ * Returns:
+ * - 0 if the confugration is valid
+ * - %-EAGAIN, if the configuration is invalid and @limits got updated
+ * with fallback values with which the configuration of all CRTCs
+ * in @state must be recomputed
+ * - Other negative error, if the configuration is invalid without a
+ * fallback possibility, or the check failed for another reason
+ */
+int intel_fdi_atomic_check_link(struct intel_atomic_state *state,
+ struct intel_link_bw_limits *limits)
+{
+ struct intel_crtc *crtc;
+ struct intel_crtc_state *crtc_state;
+ int i;
+
+ for_each_new_intel_crtc_in_state(state, crtc, crtc_state, i) {
+ int ret;
+
+ if (!crtc_state->has_pch_encoder ||
+ !intel_crtc_needs_modeset(crtc_state) ||
+ !crtc_state->hw.enable)
+ continue;
+
+ ret = intel_fdi_atomic_check_bw(state, crtc, crtc_state, limits);
+ if (ret)
+ return ret;
}
- if (needs_recompute)
- return -EAGAIN;
-
- return ret;
+ return 0;
}
static void cpt_set_fdi_bc_bifurcation(struct drm_i915_private *dev_priv, bool enable)
diff --git a/drivers/gpu/drm/i915/display/intel_fdi.h b/drivers/gpu/drm/i915/display/intel_fdi.h
index 1cdb86172702f..129444c580f27 100644
--- a/drivers/gpu/drm/i915/display/intel_fdi.h
+++ b/drivers/gpu/drm/i915/display/intel_fdi.h
@@ -8,14 +8,18 @@
enum pipe;
struct drm_i915_private;
+struct intel_atomic_state;
struct intel_crtc;
struct intel_crtc_state;
struct intel_encoder;
+struct intel_link_bw_limits;
int intel_fdi_link_freq(struct drm_i915_private *i915,
const struct intel_crtc_state *pipe_config);
int ilk_fdi_compute_config(struct intel_crtc *intel_crtc,
struct intel_crtc_state *pipe_config);
+int intel_fdi_atomic_check_link(struct intel_atomic_state *state,
+ struct intel_link_bw_limits *limits);
void intel_fdi_normal_train(struct intel_crtc *crtc);
void ilk_fdi_disable(struct intel_crtc *crtc);
void ilk_fdi_pll_disable(struct intel_crtc *intel_crtc);
diff --git a/drivers/gpu/drm/i915/display/intel_link_bw.c b/drivers/gpu/drm/i915/display/intel_link_bw.c
index 22494772b9d59..aacf22bab3135 100644
--- a/drivers/gpu/drm/i915/display/intel_link_bw.c
+++ b/drivers/gpu/drm/i915/display/intel_link_bw.c
@@ -160,7 +160,12 @@ intel_link_bw_reset_pipe_limit_to_min(struct intel_atomic_state *state,
static int check_all_link_config(struct intel_atomic_state *state,
struct intel_link_bw_limits *limits)
{
- /* TODO: Check all shared display link configurations like FDI */
+ int ret;
+
+ ret = intel_fdi_atomic_check_link(state, limits);
+ if (ret)
+ return ret;
+
return 0;
}
diff --git a/drivers/gpu/drm/i915/display/intel_lvds.c b/drivers/gpu/drm/i915/display/intel_lvds.c
index 3ace56979b70e..0366d4cc6b72b 100644
--- a/drivers/gpu/drm/i915/display/intel_lvds.c
+++ b/drivers/gpu/drm/i915/display/intel_lvds.c
@@ -48,6 +48,7 @@
#include "intel_dpll.h"
#include "intel_fdi.h"
#include "intel_gmbus.h"
+#include "intel_link_bw.h"
#include "intel_lvds.h"
#include "intel_lvds_regs.h"
#include "intel_panel.h"
@@ -425,6 +426,12 @@ static int intel_lvds_compute_config(struct intel_encoder *encoder,
return -EINVAL;
}
+ if (HAS_PCH_SPLIT(i915)) {
+ crtc_state->has_pch_encoder = true;
+ if (!intel_link_bw_compute_pipe_bpp(crtc_state))
+ return -EINVAL;
+ }
+
if (lvds_encoder->a3_power == LVDS_A3_POWER_UP)
lvds_bpp = 8*3;
else
@@ -453,9 +460,6 @@ static int intel_lvds_compute_config(struct intel_encoder *encoder,
if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
return -EINVAL;
- if (HAS_PCH_SPLIT(i915))
- crtc_state->has_pch_encoder = true;
-
ret = intel_panel_fitting(crtc_state, conn_state);
if (ret)
return ret;
diff --git a/drivers/gpu/drm/i915/display/intel_sdvo.c b/drivers/gpu/drm/i915/display/intel_sdvo.c
index 135a2527fd1b4..3c912f3bc10ba 100644
--- a/drivers/gpu/drm/i915/display/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/display/intel_sdvo.c
@@ -48,6 +48,7 @@
#include "intel_gmbus.h"
#include "intel_hdmi.h"
#include "intel_hotplug.h"
+#include "intel_link_bw.h"
#include "intel_panel.h"
#include "intel_sdvo.h"
#include "intel_sdvo_regs.h"
@@ -1351,14 +1352,17 @@ static int intel_sdvo_compute_config(struct intel_encoder *encoder,
struct drm_display_mode *adjusted_mode = &pipe_config->hw.adjusted_mode;
struct drm_display_mode *mode = &pipe_config->hw.mode;
+ if (HAS_PCH_SPLIT(to_i915(encoder->base.dev))) {
+ pipe_config->has_pch_encoder = true;
+ if (!intel_link_bw_compute_pipe_bpp(pipe_config))
+ return -EINVAL;
+ }
+
DRM_DEBUG_KMS("forcing bpc to 8 for SDVO\n");
pipe_config->pipe_bpp = 8*3;
pipe_config->sink_format = INTEL_OUTPUT_FORMAT_RGB;
pipe_config->output_format = INTEL_OUTPUT_FORMAT_RGB;
- if (HAS_PCH_SPLIT(to_i915(encoder->base.dev)))
- pipe_config->has_pch_encoder = true;
-
/*
* We need to construct preferred input timings based on our
* output timings. To do that, we have to set the output
--
2.37.2
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