Re: [Intel-gfx] [PATCH 2/2] drivers/drm/i915: Honor limits->max_bpp while computing DSC max input bpp

[Nautiyal, Ankit K]

On 8/24/2023 3:14 PM, Jani Nikula wrote:
On Wed, 23 Aug 2023, Ankit Nautiyal <ankit.k.nauti...@intel.com> wrote:
Edid specific BPC constraints are stored in limits->max_bpp. Honor these
limits while computing the input bpp for DSC.

Signed-off-by: Ankit Nautiyal <ankit.k.nauti...@intel.com>
---
  drivers/gpu/drm/i915/display/intel_dp.c | 4 +++-
  1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c 
b/drivers/gpu/drm/i915/display/intel_dp.c
index 5b48bfe09d0e..2a7f6cfe2832 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -2061,9 +2061,11 @@ static int intel_edp_dsc_compute_pipe_bpp(struct 
intel_dp *intel_dp,
        if (forced_bpp) {
                pipe_bpp = forced_bpp;
        } else {
+               u8 max_bpc = limits->max_bpp / 3;
+
                int max_bpc = min_t(int, limits->max_bpp / 3, 
conn_state->max_requested_bpc);

                /* For eDP use max bpp that can be supported with DSC. */
                pipe_bpp = intel_dp_dsc_compute_max_bpp(intel_dp, max_bbc);
Nitpick, IMO looks cleaner this way, as well as uses int instead of u8
for computations.

BR,
Jani.

Thanks Jani for the comments, it does makes sense. Will fix in next 
version shortly.

Regards,

Ankit

                if (!is_dsc_pipe_bpp_sufficient(i915, conn_state, limits, 
pipe_bpp)) {
                        drm_dbg_kms(&i915->drm,
                                    "Computed BPC is not in DSC BPC limits\n");