| Message ID | 20221009184824.457416-6-marijn.suijten@somainline.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/msm: Fix math issues in MSM DSC implementation | expand |
On 09/10/2022 21:48, Marijn Suijten wrote: > This field is currently unread but will come into effect when duplicated > code below is migrated to call drm_dsc_compute_rc_parameters(), which > uses the bpc-dependent value of the local variable mux_words_size in > much the same way. > > The hardcoded constant seems to be a remnant from the `/* bpc 8 */` > comment right above, indicating that this group of field assignments is > applicable to bpc = 8 exclusively and should probably bail out on > different bpc values, until constants for other bpc values are added (or > the current ones are confirmed to be correct across multiple bpc's). > > Fixes: b9080324d6ca ("drm/msm/dsi: add support for dsc data") > Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
On 10/9/2022 11:48 AM, Marijn Suijten wrote: > This field is currently unread but will come into effect when duplicated > code below is migrated to call drm_dsc_compute_rc_parameters(), which > uses the bpc-dependent value of the local variable mux_words_size in > much the same way. > > The hardcoded constant seems to be a remnant from the `/* bpc 8 */` > comment right above, indicating that this group of field assignments is > applicable to bpc = 8 exclusively and should probably bail out on > different bpc values, until constants for other bpc values are added (or > the current ones are confirmed to be correct across multiple bpc's). > Yes, this seems to hard-code it to 8bpc/10bpc. So your code-change is fine. Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com> > Fixes: b9080324d6ca ("drm/msm/dsi: add support for dsc data") > Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org> > --- > drivers/gpu/drm/msm/dsi/dsi_host.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c > index f42794cdd4c1..83cde4d62b68 100644 > --- a/drivers/gpu/drm/msm/dsi/dsi_host.c > +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c > @@ -1808,6 +1808,7 @@ static int dsi_populate_dsc_params(struct drm_dsc_config *dsc) > if (dsc->bits_per_component == 12) > mux_words_size = 64; > > + dsc->mux_word_size = mux_words_size; > dsc->initial_xmit_delay = 512; > dsc->initial_scale_value = 32; > dsc->first_line_bpg_offset = 12; > @@ -1818,7 +1819,6 @@ static int dsi_populate_dsc_params(struct drm_dsc_config *dsc) > dsc->flatness_max_qp = 12; > dsc->rc_quant_incr_limit0 = 11; > dsc->rc_quant_incr_limit1 = 11; > - dsc->mux_word_size = DSC_MUX_WORD_SIZE_8_10_BPC; > > /* FIXME: need to call drm_dsc_compute_rc_parameters() so that rest of > * params are calculated
diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c index f42794cdd4c1..83cde4d62b68 100644 --- a/drivers/gpu/drm/msm/dsi/dsi_host.c +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c @@ -1808,6 +1808,7 @@ static int dsi_populate_dsc_params(struct drm_dsc_config *dsc) if (dsc->bits_per_component == 12) mux_words_size = 64; + dsc->mux_word_size = mux_words_size; dsc->initial_xmit_delay = 512; dsc->initial_scale_value = 32; dsc->first_line_bpg_offset = 12; @@ -1818,7 +1819,6 @@ static int dsi_populate_dsc_params(struct drm_dsc_config *dsc) dsc->flatness_max_qp = 12; dsc->rc_quant_incr_limit0 = 11; dsc->rc_quant_incr_limit1 = 11; - dsc->mux_word_size = DSC_MUX_WORD_SIZE_8_10_BPC; /* FIXME: need to call drm_dsc_compute_rc_parameters() so that rest of * params are calculated
This field is currently unread but will come into effect when duplicated code below is migrated to call drm_dsc_compute_rc_parameters(), which uses the bpc-dependent value of the local variable mux_words_size in much the same way. The hardcoded constant seems to be a remnant from the `/* bpc 8 */` comment right above, indicating that this group of field assignments is applicable to bpc = 8 exclusively and should probably bail out on different bpc values, until constants for other bpc values are added (or the current ones are confirmed to be correct across multiple bpc's). Fixes: b9080324d6ca ("drm/msm/dsi: add support for dsc data") Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org> --- drivers/gpu/drm/msm/dsi/dsi_host.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)