[Intel-gfx] [PATCH 05/11] drm/i915: Check lane count when determining FEC support

[Ville Syrjala]

From: Ville Syrjälä <ville.syrj...@linux.intel.com>

ICL doesn't support FEC with a x1 DP link. Make sure
we don't try to enable FEC in such cases.

Signed-off-by: Ville Syrjälä <ville.syrj...@linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c 
b/drivers/gpu/drm/i915/display/intel_dp.c
index b27b4fb71ed7..9ac199444155 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -1218,7 +1218,8 @@ static bool intel_dp_source_supports_fec(struct intel_dp 
*intel_dp,
        if (DISPLAY_VER(dev_priv) >= 12)
                return true;
 
-       if (DISPLAY_VER(dev_priv) == 11 && encoder->port != PORT_A)
+       if (DISPLAY_VER(dev_priv) == 11 &&
+           encoder->port != PORT_A && pipe_config->lane_count != 1)
                return true;
 
        return false;
@@ -1234,7 +1235,7 @@ static bool intel_dp_supports_fec(struct intel_dp 
*intel_dp,
 static bool intel_dp_supports_dsc(struct intel_dp *intel_dp,
                                  const struct intel_crtc_state *crtc_state)
 {
-       if (intel_crtc_has_type(crtc_state, INTEL_OUTPUT_DP) && 
!crtc_state->fec_enable)
+       if (!intel_dp_is_edp(intel_dp) && !crtc_state->fec_enable)
                return false;
 
        return intel_dsc_source_support(crtc_state) &&
@@ -1580,15 +1581,6 @@ int intel_dp_dsc_compute_config(struct intel_dp 
*intel_dp,
        int pipe_bpp;
        int ret;
 
-       pipe_config->fec_enable = !intel_dp_is_edp(intel_dp) &&
-               intel_dp_supports_fec(intel_dp, pipe_config);
-
-       if (!intel_dp_supports_dsc(intel_dp, pipe_config))
-               return -EINVAL;
-
-       if (!intel_dp_dsc_supports_format(intel_dp, pipe_config->output_format))
-               return -EINVAL;
-
        if (compute_pipe_bpp)
                pipe_bpp = intel_dp_dsc_compute_bpp(intel_dp, 
conn_state->max_requested_bpc);
        else
@@ -1615,6 +1607,15 @@ int intel_dp_dsc_compute_config(struct intel_dp 
*intel_dp,
        pipe_config->port_clock = limits->max_rate;
        pipe_config->lane_count = limits->max_lane_count;
 
+       pipe_config->fec_enable = !intel_dp_is_edp(intel_dp) &&
+               intel_dp_supports_fec(intel_dp, pipe_config);
+
+       if (!intel_dp_supports_dsc(intel_dp, pipe_config))
+               return -EINVAL;
+
+       if (!intel_dp_dsc_supports_format(intel_dp, pipe_config->output_format))
+               return -EINVAL;
+
        if (intel_dp_is_edp(intel_dp)) {
                pipe_config->dsc.compressed_bpp =
                        min_t(u16, 
drm_edp_dsc_sink_output_bpp(intel_dp->dsc_dpcd) >> 4,
-- 
2.39.2