Re: [PATCH] drm/mediatek: add mt8183 dpi support

From: CK Hu
Date: Mon Feb 18 2019 - 21:36:47 EST


Hi, Jitao:

On Tue, 2019-02-19 at 09:53 +0800, Jitao Shi wrote:
> On Fri, 2019-02-15 at 00:13 +0800, CK Hu wrote:
> > Hi, Jitao:
> >
> > On Mon, 2019-02-11 at 12:50 +0800, Jitao Shi wrote:
> > > MT8183 sample on rising and falling edge. It can reduce half data io.
> > >
> > > Signed-off-by: Jitao Shi <jitao.shi@xxxxxxxxxxxx>
> > > ---
> > > drivers/gpu/drm/mediatek/mtk_dpi.c | 29 +++++++++++++++++++++++++++++
> > > 1 file changed, 29 insertions(+)
> > >
> > > diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c
> > > index 62a9d47df948..610c23334047 100644
> > > --- a/drivers/gpu/drm/mediatek/mtk_dpi.c
> > > +++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
> > > @@ -117,6 +117,7 @@ struct mtk_dpi_conf {
> > > unsigned int (*cal_factor)(int clock);
> > > u32 reg_h_fre_con;
> > > bool edge_sel_en;
> > > + bool dual_edge;
> > > };
> > >
> > > static void mtk_dpi_mask(struct mtk_dpi *dpi, u32 offset, u32 val, u32 mask)
> > > @@ -353,6 +354,13 @@ static void mtk_dpi_config_disable_edge(struct mtk_dpi *dpi)
> > > mtk_dpi_mask(dpi, dpi->conf->reg_h_fre_con, 0, EDGE_SEL_EN);
> > > }
> > >
> > > +static void mtk_dpi_enable_dual_edge(struct mtk_dpi *dpi)
> > > +{
> > > + mtk_dpi_mask(dpi, DPI_DDR_SETTING, DDR_EN | DDR_4PHASE,
> > > + DDR_EN | DDR_4PHASE);
> > > + mtk_dpi_mask(dpi, DPI_OUTPUT_SETTING, EDGE_SEL, EDGE_SEL);
> > > +}
> >
> > All these register exist in MT8173, if you do the same setting in
> > MT8173, could it also sample on rising edge and falling edge?
> >
> > Regards,
> > CK
>
> Hi CK,
>
> MT8173 has those registers. But the hw function is removed.
> So MT8173 doesn't support DPI dual edge sample.

OK, please add this information in commit message.

Regards,
CK

>
> Best Regards
> Jitao
>
> >
> > > +
> > > static void mtk_dpi_config_color_format(struct mtk_dpi *dpi,
> > > enum mtk_dpi_out_color_format format)
> > > {
> > > @@ -509,6 +517,8 @@ static int mtk_dpi_set_display_mode(struct mtk_dpi *dpi,
> > > mtk_dpi_config_color_format(dpi, dpi->color_format);
> > > mtk_dpi_config_2n_h_fre(dpi);
> > > mtk_dpi_config_disable_edge(dpi);
> > > + if (dpi->conf->dual_edge)
> > > + mtk_dpi_enable_dual_edge(dpi);
> > > mtk_dpi_sw_reset(dpi, false);
> > >
> > > return 0;
> > > @@ -671,6 +681,16 @@ static unsigned int mt2701_calculate_factor(int clock)
> > > return 2;
> > > }
> > >
> > > +static unsigned int mt8183_calculate_factor(int clock)
> > > +{
> > > + if (clock <= 27000)
> > > + return 8;
> > > + else if (clock <= 167000)
> > > + return 4;
> > > + else
> > > + return 2;
> > > +}
> > > +
> > > static const struct mtk_dpi_conf mt8173_conf = {
> > > .cal_factor = mt8173_calculate_factor,
> > > .reg_h_fre_con = 0xe0,
> > > @@ -682,6 +702,12 @@ static const struct mtk_dpi_conf mt2701_conf = {
> > > .edge_sel_en = true,
> > > };
> > >
> > > +static const struct mtk_dpi_conf mt8183_conf = {
> > > + .cal_factor = mt8183_calculate_factor,
> > > + .reg_h_fre_con = 0xe0,
> > > + .dual_edge = true,
> > > +};
> > > +
> > > static int mtk_dpi_probe(struct platform_device *pdev)
> > > {
> > > struct device *dev = &pdev->dev;
> > > @@ -777,6 +803,9 @@ static const struct of_device_id mtk_dpi_of_ids[] = {
> > > { .compatible = "mediatek,mt8173-dpi",
> > > .data = &mt8173_conf,
> > > },
> > > + { .compatible = "mediatek,mt8183-dpi",
> > > + .data = &mt8183_conf,
> > > + },
> > > { },
> > > };
> > >
> >
> >
>
>