[Intel-gfx] [PATCH 5/5] drm/i915: Add YCBCR 4:2:0 support for LSPCON
Shashank Sharma
shashank.sharma at intel.com
Tue Nov 14 15:17:26 UTC 2017
LSPCON chips are capable of generating YCBCR 4:2:0 outputs, if asked
nicely :). In order to generate YCBCR 4:2:0 outputs, a source must:
- send YCBCR 4:4:4 signals to LSPCON
- program color space as 4:2:0 in AVI infoframes
This will indicate LSPCON FW to start scaling down from YCBCR 4:4:4
and generate YCBCR 4:2:0 output. Unlike HDMI 2.0 native case, as the
scaling is done by LSPCON device, we need not to reserve a scaler for
4:2:0 outputs.
Signed-off-by: Shashank Sharma <shashank.sharma at intel.com>
---
drivers/gpu/drm/i915/i915_reg.h | 2 ++
drivers/gpu/drm/i915/intel_ddi.c | 8 ++++++++
drivers/gpu/drm/i915/intel_display.c | 15 +++++++++++----
drivers/gpu/drm/i915/intel_dp.c | 7 ++++++-
drivers/gpu/drm/i915/intel_drv.h | 2 ++
drivers/gpu/drm/i915/intel_lspcon.c | 22 ++++++++++++++++++++++
6 files changed, 51 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index f0f8f60..ea6ef5e 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -8495,6 +8495,8 @@ enum skl_power_gate {
#define TRANS_MSA_MISC(tran) _MMIO_TRANS2(tran, _TRANSA_MSA_MISC)
#define TRANS_MSA_SYNC_CLK (1<<0)
+#define TRANS_MSA_SAMPLING_444 (2<<1)
+#define TRANS_MSA_CLRSP_YCBCR (2<<3)
#define TRANS_MSA_6_BPC (0<<5)
#define TRANS_MSA_8_BPC (1<<5)
#define TRANS_MSA_10_BPC (2<<5)
diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index 9e2ab02..3fd839d 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -1499,6 +1499,14 @@ void intel_ddi_set_pipe_settings(const struct intel_crtc_state *crtc_state)
break;
}
+ /*
+ * To get YCBCR 420 output from LSPCON, we should send YCBCR 444
+ * signals. And as per DP 1.2 spec section 2.3.4.3 while sending
+ * YCBCR 444 signals we should program MSA MISC1/0 fields with
+ * colorspace information.
+ */
+ if (crtc_state->lspcon_active && crtc_state->ycbcr420)
+ temp |= TRANS_MSA_SAMPLING_444 | TRANS_MSA_CLRSP_YCBCR;
I915_WRITE(TRANS_MSA_MISC(cpu_transcoder), temp);
}
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 737de25..787119b 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4638,7 +4638,8 @@ skl_update_scaler(struct intel_crtc_state *crtc_state, bool force_detach,
*/
need_scaling = src_w != dst_w || src_h != dst_h;
- if (crtc_state->ycbcr420 && scaler_user == SKL_CRTC_INDEX)
+ if (crtc_state->ycbcr420 && scaler_user == SKL_CRTC_INDEX &&
+ !crtc_state->lspcon_active)
need_scaling = true;
/*
@@ -8133,9 +8134,15 @@ static void haswell_set_pipemisc(struct drm_crtc *crtc)
val |= PIPEMISC_DITHER_ENABLE | PIPEMISC_DITHER_TYPE_SP;
if (config->ycbcr420) {
- val |= PIPEMISC_OUTPUT_COLORSPACE_YUV |
- PIPEMISC_YUV420_ENABLE |
- PIPEMISC_YUV420_MODE_FULL_BLEND;
+ val |= PIPEMISC_OUTPUT_COLORSPACE_YUV;
+ /*
+ * LSPCON doesn't need scaling/blending to be done in
+ * pipe. It just needs YCBCR444 input and proper AVI
+ * infoframes for 4:2:0 output enabling.
+ */
+ if (!config->lspcon_active)
+ val |= PIPEMISC_YUV420_ENABLE |
+ PIPEMISC_YUV420_MODE_FULL_BLEND;
}
I915_WRITE(PIPEMISC(intel_crtc->pipe), val);
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index fa9e5e6..1d4b669 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1657,8 +1657,13 @@ intel_dp_compute_config(struct intel_encoder *encoder,
intel_dp->max_link_rate);
/* LSPCON needs special handling to drive YCBCR420 outputs */
- if (lspcon->active)
+ if (lspcon->active) {
+ struct drm_connector *connector = &intel_connector->base;
+
pipe_config->lspcon_active = true;
+ pipe_config->ycbcr420 = lspcon_ycbcr420_config(connector,
+ pipe_config);
+ }
/* No common link rates between source and sink */
WARN_ON(common_len <= 0);
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index a468dd6..f271967 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -2047,6 +2047,8 @@ void lspcon_set_infoframes(struct drm_encoder *encoder,
const struct drm_connector_state *conn_state);
bool lspcon_infoframe_enabled(struct drm_encoder *encoder,
const struct intel_crtc_state *pipe_config);
+bool lspcon_ycbcr420_config(struct drm_connector *connector,
+ struct intel_crtc_state *config);
/* intel_pipe_crc.c */
int intel_pipe_crc_create(struct drm_minor *minor);
diff --git a/drivers/gpu/drm/i915/intel_lspcon.c b/drivers/gpu/drm/i915/intel_lspcon.c
index 77f0687..ca77f50 100644
--- a/drivers/gpu/drm/i915/intel_lspcon.c
+++ b/drivers/gpu/drm/i915/intel_lspcon.c
@@ -180,6 +180,26 @@ static bool lspcon_wake_native_aux_ch(struct intel_lspcon *lspcon)
return true;
}
+bool lspcon_ycbcr420_config(struct drm_connector *connector,
+ struct intel_crtc_state *config)
+{
+ struct drm_display_info *info = &connector->display_info;
+ struct drm_display_mode *mode = &config->base.adjusted_mode;
+
+ if (drm_mode_is_420_only(info, mode)) {
+
+ if (!connector->ycbcr_420_allowed) {
+ DRM_ERROR("Platform doesn't support YCBCR420 output\n");
+ return false;
+ }
+
+ config->port_clock /= 2;
+ return true;
+ }
+
+ return false;
+}
+
static bool lspcon_probe(struct intel_lspcon *lspcon)
{
int retry;
@@ -516,6 +536,7 @@ bool lspcon_init(struct intel_digital_port *intel_dig_port)
struct intel_lspcon *lspcon = &intel_dig_port->lspcon;
struct drm_device *dev = intel_dig_port->base.base.dev;
struct drm_i915_private *dev_priv = to_i915(dev);
+ struct drm_connector *connector = &dp->attached_connector->base;
if (!HAS_LSPCON(dev_priv)) {
DRM_ERROR("LSPCON is not supported on this platform\n");
@@ -540,6 +561,7 @@ bool lspcon_init(struct intel_digital_port *intel_dig_port)
return false;
}
+ connector->ycbcr_420_allowed = true;
lspcon->active = true;
DRM_DEBUG_KMS("Success: LSPCON init\n");
return true;
--
2.7.4
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