The Bspec:70151, mentions Chroma subsampling is a 2x downscale
operation. This means that the downscale factor is 2 in each direction.
So correct the downscaling factor to 4.
Signed-off-by: Ankit Nautiyal <ankit.k.nauti...@intel.com>
Reviewed-by: Mitul Golani <mitulkumar.ajitkumar.gol...@intel.com>
---
drivers/gpu/drm/i915/display/skl_watermark.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/skl_watermark.c
b/drivers/gpu/drm/i915/display/skl_watermark.c
index def5150231a4..df586509a742 100644
--- a/drivers/gpu/drm/i915/display/skl_watermark.c
+++ b/drivers/gpu/drm/i915/display/skl_watermark.c
@@ -2185,7 +2185,7 @@ dsc_prefill_latency(const struct intel_crtc_state
*crtc_state)
crtc_state->hw.adjusted_mode.clock);
int num_scaler_users = hweight32(scaler_state->scaler_users);
int chroma_downscaling_factor =
- crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR420 ? 2 :
1;
+ crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR420 ? 4 :
1;
u32 dsc_prefill_latency = 0;
if (!crtc_state->dsc.compression_enable ||
@@ -2228,7 +2228,7 @@ scaler_prefill_latency(const struct intel_crtc_state
*crtc_state)
u64 hscale_k = max(1000,
mul_u32_u32(scaler_state->scalers[0].hscale, 1000) >> 16);
u64 vscale_k = max(1000,
mul_u32_u32(scaler_state->scalers[0].vscale, 1000) >> 16);
int chroma_downscaling_factor =
- crtc_state->output_format ==
INTEL_OUTPUT_FORMAT_YCBCR420 ? 2 : 1;
+ crtc_state->output_format ==
INTEL_OUTPUT_FORMAT_YCBCR420 ? 4 : 1;
int latency;
latency = DIV_ROUND_UP_ULL((4 * linetime * hscale_k * vscale_k *
--
2.45.2
