On 2023-05-05 14:49:08, Jessica Zhang wrote:
> On 5/5/2023 2:23 PM, Jessica Zhang wrote:
> > Adjust the pclk rate to divide hdisplay by the compression ratio when DSC
> > is enabled.
> >
> > Changes in v2:
> > - Adjusted pclk_rate math to divide only the hdisplay value by
> > compression ratio
> >
> > Signed-off-by: Jessica Zhang <quic_jesszhan@xxxxxxxxxxx>
> > ---
> > drivers/gpu/drm/msm/dsi/dsi_host.c | 17 +++++++++++++----
> > 1 file changed, 13 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
> > index 43a5ec33eee8..0e5778e8091f 100644
> > --- a/drivers/gpu/drm/msm/dsi/dsi_host.c
> > +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
> > @@ -561,7 +561,8 @@ void dsi_link_clk_disable_v2(struct msm_dsi_host *msm_host)
> > clk_disable_unprepare(msm_host->byte_clk);
> > }
> >
> > -static unsigned long dsi_get_pclk_rate(const struct drm_display_mode *mode, bool is_bonded_dsi)
> > +static unsigned long dsi_get_pclk_rate(const struct drm_display_mode *mode,
> > + struct drm_dsc_config *dsc, bool is_bonded_dsi)
> > {
> > unsigned long pclk_rate;
> >
> > @@ -576,6 +577,14 @@ static unsigned long dsi_get_pclk_rate(const struct drm_display_mode *mode, bool
> > if (is_bonded_dsi)
> > pclk_rate /= 2;
> >
> > + /* If DSC is enabled, divide hdisplay by compression ratio */
> > + if (dsc) {
> > + int new_hdisplay = DIV_ROUND_UP(mode->hdisplay * msm_dsc_get_bpp_int(dsc),
> > + dsc->bits_per_component * 3);
> > + int fps = DIV_ROUND_UP(pclk_rate, mode->htotal * mode->vtotal);
>
> Should've used drm_mode_vrefresh() here... Will spin a v3 with that
> change (along with any additional comments)
Perhaps unsigned long on some of these? Overall the computations and
multi-lines look rather cluttered, perhaps (parts of) this is/are a
prime candidate to go into the new helpers?
Note that I cannot get the 4k mode working at 60Hz on one of my panels
(30Hz works with minor corruption), regardless of this patch. See also:
https://gitlab.freedesktop.org/drm/msm/-/issues/24#note_1900031
> > + pclk_rate = (new_hdisplay + (mode->htotal - mode->hdisplay)) * mode->vtotal * fps;
> > + }
> > +
> > return pclk_rate;
> > }
> >
> > @@ -585,7 +594,7 @@ unsigned long dsi_byte_clk_get_rate(struct mipi_dsi_host *host, bool is_bonded_d
> > struct msm_dsi_host *msm_host = to_msm_dsi_host(host);
> > u8 lanes = msm_host->lanes;
> > u32 bpp = dsi_get_bpp(msm_host->format);
> > - unsigned long pclk_rate = dsi_get_pclk_rate(mode, is_bonded_dsi);
> > + unsigned long pclk_rate = dsi_get_pclk_rate(mode, msm_host->dsc, is_bonded_dsi);
> > u64 pclk_bpp = (u64)pclk_rate * bpp;
> >
> > if (lanes == 0) {
> > @@ -604,7 +613,7 @@ unsigned long dsi_byte_clk_get_rate(struct mipi_dsi_host *host, bool is_bonded_d
> >
> > static void dsi_calc_pclk(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
> > {
> > - msm_host->pixel_clk_rate = dsi_get_pclk_rate(msm_host->mode, is_bonded_dsi);
> > + msm_host->pixel_clk_rate = dsi_get_pclk_rate(msm_host->mode, msm_host->dsc, is_bonded_dsi);
> > msm_host->byte_clk_rate = dsi_byte_clk_get_rate(&msm_host->base, is_bonded_dsi,
> > msm_host->mode);
> >
> > @@ -634,7 +643,7 @@ int dsi_calc_clk_rate_v2(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
> >
> > dsi_calc_pclk(msm_host, is_bonded_dsi);
> >
> > - pclk_bpp = (u64)dsi_get_pclk_rate(msm_host->mode, is_bonded_dsi) * bpp;
> > + pclk_bpp = (u64)dsi_get_pclk_rate(msm_host->mode, msm_host->dsc, is_bonded_dsi) * bpp;
Let's rebase on top of "drm/msm/dsi: simplify pixel clk rate handling"
[1] to clean this up.
[1]: https://lore.kernel.org/linux-arm-msm/20230118130031.2345941-1-dmitry.baryshkov@xxxxxxxxxx/
- Marijn
> > do_div(pclk_bpp, 8);
> > msm_host->src_clk_rate = pclk_bpp;
> >
> >
> > --
> > 2.40.1
> >
