On Wed, Mar 29, 2023 at 05:00:55PM +0530, Nautiyal, Ankit K wrote:
>
> On 3/29/2023 4:23 PM, Ville Syrjälä wrote:
> > On Wed, Mar 29, 2023 at 04:06:21PM +0530, Nautiyal, Ankit K wrote:
> >> On 3/29/2023 3:27 PM, Ville Syrjälä wrote:
> >>> On Wed, Mar 29, 2023 at 02:14:49PM +0530, Ankit Nautiyal wrote:
> >>>> As per Bspec, Big Joiner BW check is:
> >>>> Output bpp <= PPC * CDCLK frequency * Big joiner interface bits /
> >>>> Pixel clock
> >>>>
> >>>> Currently we always use max_cdclk in the check for both modevalid
> >>>> and compute config steps.
> >>>>
> >>>> During modevalid use max_cdclk_freq for the check.
> >>>> During compute config step use current cdclk for the check.
> >>> Nak. cdclk is computed much later based on what is actually needed.
> >>> The cdclk freq you are using here is essentially a random number.
> >> Oh I didn't realise that, perhaps I was lucky when I tested this.
> >>
> >> So this check where CDCLK is mentioned, actually expects max_cdclk_freq?
> >>
> >> If it doesnt then, we might have a compressed_bpp value, that might be
> >> violating the big joiner bw check.
> >>
> >> Should this be handled while computing cdclk?
> > Yes. I suggest adding something like intel_vdsc_min_cdclk() that
> > handles all of it.
>
>
> I can try that out.
>
> Will also add *Pipe BW check*: Pixel clock < PPC * CDCLK frequency *
> Number of pipes joined, which seems to be missing.
That is already accounted for in the pixel rate.
>
> So with pipe bw_check cdclk should be > Pixel clock / (PPC * Number of
> pipes joined)
>
> In addition, as per bigjoiner check it should be >= compressed_bpp /
> (PPC * bigjoiner interface bits).
>
> Regards,
>
> Ankit
>
> >> Regards,
> >>
> >> Ankit
> >>
> >>>> Signed-off-by: Ankit Nautiyal <ankit.k.nauti...@intel.com>
> >>>> ---
> >>>> drivers/gpu/drm/i915/display/intel_dp.c | 9 ++++++---
> >>>> drivers/gpu/drm/i915/display/intel_dp.h | 1 +
> >>>> drivers/gpu/drm/i915/display/intel_dp_mst.c | 1 +
> >>>> 3 files changed, 8 insertions(+), 3 deletions(-)
> >>>>
> >>>> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> >>>> b/drivers/gpu/drm/i915/display/intel_dp.c
> >>>> index 3fe651a8f5d0..d6600de1ab49 100644
> >>>> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> >>>> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> >>>> @@ -711,6 +711,7 @@ u32 intel_dp_dsc_nearest_valid_bpp(struct
> >>>> drm_i915_private *i915, u32 bpp, u32 p
> >>>> u16 intel_dp_dsc_get_output_bpp(struct drm_i915_private *i915,
> >>>> u32 link_clock, u32 lane_count,
> >>>> u32 mode_clock, u32 mode_hdisplay,
> >>>> + unsigned int cdclk,
> >>>> bool bigjoiner,
> >>>> u32 pipe_bpp,
> >>>> u32 timeslots)
> >>>> @@ -757,9 +758,9 @@ u16 intel_dp_dsc_get_output_bpp(struct
> >>>> drm_i915_private *i915,
> >>>>
> >>>> if (bigjoiner) {
> >>>> int bigjoiner_interface_bits = DISPLAY_VER(i915) <= 12
> >>>> ? 24 : 36;
> >>>> - u32 max_bpp_bigjoiner =
> >>>> - i915->display.cdclk.max_cdclk_freq * 2 *
> >>>> bigjoiner_interface_bits /
> >>>> - intel_dp_mode_to_fec_clock(mode_clock);
> >>>> +
> >>>> + u32 max_bpp_bigjoiner = cdclk * 2 *
> >>>> bigjoiner_interface_bits /
> >>>> +
> >>>> intel_dp_mode_to_fec_clock(mode_clock);
> >>>>
> >>>> bits_per_pixel = min(bits_per_pixel, max_bpp_bigjoiner);
> >>>> }
> >>>> @@ -1073,6 +1074,7 @@ intel_dp_mode_valid(struct drm_connector
> >>>> *_connector,
> >>>> max_lanes,
> >>>>
> >>>> target_clock,
> >>>>
> >>>> mode->hdisplay,
> >>>> +
> >>>> dev_priv->display.cdclk.max_cdclk_freq,
> >>>> bigjoiner,
> >>>> pipe_bpp,
> >>>> 64) >> 4;
> >>>> dsc_slice_count =
> >>>> @@ -1580,6 +1582,7 @@ int intel_dp_dsc_compute_config(struct intel_dp
> >>>> *intel_dp,
> >>>>
> >>>> pipe_config->lane_count,
> >>>>
> >>>> adjusted_mode->crtc_clock,
> >>>>
> >>>> adjusted_mode->crtc_hdisplay,
> >>>> +
> >>>> dev_priv->display.cdclk.hw.cdclk,
> >>>>
> >>>> pipe_config->bigjoiner_pipes,
> >>>> pipe_bpp,
> >>>> timeslots);
> >>>> diff --git a/drivers/gpu/drm/i915/display/intel_dp.h
> >>>> b/drivers/gpu/drm/i915/display/intel_dp.h
> >>>> index ef39e4f7a329..d150bfe8abf4 100644
> >>>> --- a/drivers/gpu/drm/i915/display/intel_dp.h
> >>>> +++ b/drivers/gpu/drm/i915/display/intel_dp.h
> >>>> @@ -106,6 +106,7 @@ int intel_dp_dsc_compute_bpp(struct intel_dp
> >>>> *intel_dp, u8 dsc_max_bpc);
> >>>> u16 intel_dp_dsc_get_output_bpp(struct drm_i915_private *i915,
> >>>> u32 link_clock, u32 lane_count,
> >>>> u32 mode_clock, u32 mode_hdisplay,
> >>>> + unsigned int cdclk,
> >>>> bool bigjoiner,
> >>>> u32 pipe_bpp,
> >>>> u32 timeslots);
> >>>> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> >>>> b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> >>>> index a860cbc5dbea..266e31b78729 100644
> >>>> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> >>>> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> >>>> @@ -925,6 +925,7 @@ intel_dp_mst_mode_valid_ctx(struct drm_connector
> >>>> *connector,
> >>>> max_lanes,
> >>>>
> >>>> target_clock,
> >>>>
> >>>> mode->hdisplay,
> >>>> +
> >>>> dev_priv->display.cdclk.max_cdclk_freq,
> >>>> bigjoiner,
> >>>> pipe_bpp,
> >>>> 64) >> 4;
> >>>> dsc_slice_count =
> >>>> --
> >>>> 2.25.1
--
Ville Syrjälä
Intel
