Re: [PATCH v17 11/21] drm/mediatek: add display merge start/stop API for cmdq support

[Matthias Brugger]

On 25/04/2022 15:32, Chun-Kuang Hu wrote:
> Hi, Matthias:
>
> Matthias Brugger <matthias.bgg@xxxxxxxxx> 於 2022年4月22日 週五 下午7:48寫道：
> > On 16/04/2022 04:07, Nancy.Lin wrote:
> > > Add merge start/stop API for cmdq support. The ovl_adaptor merges
> > > are configured with each drm plane update. Need to enable/disable
> > > merge with cmdq making sure all the settings taken effect in the
> > > same vblank.
> > >
> > > Signed-off-by: Nancy.Lin <nancy.lin@xxxxxxxxxxxx>
> > > Reviewed-by: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx>
> > > Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
> > > ---
> > >    drivers/gpu/drm/mediatek/mtk_disp_drv.h   |  2 ++
> > >    drivers/gpu/drm/mediatek/mtk_disp_merge.c | 20 +++++++++++++++++---
> > >    2 files changed, 19 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/mediatek/mtk_disp_drv.h b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> > > index 53aa988dde3b..43a412525b75 100644
> > > --- a/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> > > +++ b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> > > @@ -66,6 +66,8 @@ void mtk_merge_stop(struct device *dev);
> > >    void mtk_merge_advance_config(struct device *dev, unsigned int l_w, unsigned int r_w,
> > >                              unsigned int h, unsigned int vrefresh, unsigned int bpc,
> > >                              struct cmdq_pkt *cmdq_pkt);
> > > +void mtk_merge_start_cmdq(struct device *dev, struct cmdq_pkt *cmdq_pkt);
> > > +void mtk_merge_stop_cmdq(struct device *dev, struct cmdq_pkt *cmdq_pkt);
> > >
> > >    void mtk_ovl_bgclr_in_on(struct device *dev);
> > >    void mtk_ovl_bgclr_in_off(struct device *dev);
> > > diff --git a/drivers/gpu/drm/mediatek/mtk_disp_merge.c b/drivers/gpu/drm/mediatek/mtk_disp_merge.c
> > > index 40da0555416d..c0d9b43b2a66 100644
> > > --- a/drivers/gpu/drm/mediatek/mtk_disp_merge.c
> > > +++ b/drivers/gpu/drm/mediatek/mtk_disp_merge.c
> > > @@ -67,17 +67,31 @@ struct mtk_disp_merge {
> > >    };
> > >
> > >    void mtk_merge_start(struct device *dev)
> >
> > Probably not my call, but wouldn't it make sense to enhance mtk_merge_start to
> > pass 'struct cmdq_pkt *cmdq_pkt' directly instead of adding this 'adapter'?
>
> In [1], mtk_merge_start() should match the function prototype of
> mtk_ddp_comp_funcs.start, so keep the non-cmdq interface.

Well other callbacks, namely config hass cmdq_pkt. So we could change the 
callback in a similar way is was done in
d0afe37f5209 ("drm/mediatek: support CMDQ interface in ddp component")


But as i said it's up to you. You are the maintainer.

Regards,
Matthias

> static const struct mtk_ddp_comp_funcs ddp_merge = {
>   .clk_enable = mtk_merge_clk_enable,
>   .clk_disable = mtk_merge_clk_disable,
>   .start = mtk_merge_start,
>   .stop = mtk_merge_stop,
>   .config = mtk_merge_config,
> };
>
> [1] https://patchwork.kernel.org/project/linux-mediatek/patch/20220419094143.9561-5-jason-jh.lin@xxxxxxxxxxxx/
>
> Regards,
> Chun-Kuang.
>
> > In the end this is up to Chun-Kuang.
> >
> > Regards,
> > Matthias
> >
> > > +{
> > > +     mtk_merge_start_cmdq(dev, NULL);
> > > +}
> > > +
> > > +void mtk_merge_stop(struct device *dev)
> > >    {
> > >        struct mtk_disp_merge *priv = dev_get_drvdata(dev);
> > >
> > > -     writel(MERGE_EN, priv->regs + DISP_REG_MERGE_CTRL);
> > > +     mtk_merge_stop_cmdq(dev, NULL);
> > >    }
> > >
> > > -void mtk_merge_stop(struct device *dev)
> > > +void mtk_merge_start_cmdq(struct device *dev, struct cmdq_pkt *cmdq_pkt)
> > > +{
> > > +     struct mtk_disp_merge *priv = dev_get_drvdata(dev);
> > > +
> > > +     mtk_ddp_write(cmdq_pkt, 1, &priv->cmdq_reg, priv->regs,
> > > +                   DISP_REG_MERGE_CTRL);
> > > +}
> > > +
> > > +void mtk_merge_stop_cmdq(struct device *dev, struct cmdq_pkt *cmdq_pkt)
> > >    {
> > >        struct mtk_disp_merge *priv = dev_get_drvdata(dev);
> > >
> > > -     writel(0x0, priv->regs + DISP_REG_MERGE_CTRL);
> > > +     mtk_ddp_write(cmdq_pkt, 0, &priv->cmdq_reg, priv->regs,
> > > +                   DISP_REG_MERGE_CTRL);
> > >    }
> > >
> > >    static void mtk_merge_fifo_setting(struct mtk_disp_merge *priv,