[PATCH] drivers: mmc: mtk-sd: disable dma for MT8188 and MT8195

[Julien Stephan]

Le mar. 17 mars 2026 à 15:21, David Lechner <dlechner at baylibre.com> a écrit :
>
> On 3/17/26 8:31 AM, Julien Stephan wrote:
> > MT8188 and MT8195 SoC should be fully compatible with MT8183, but
> > currently dma is not working on these SoC. For now, disable dma.
> > Investigation needed.
> >
> > Signed-off-by: Julien Stephan <jstephan at baylibre.com>
> > ---
> >  drivers/mmc/mtk-sd.c | 26 ++++++++++++++++++++++++++
> >  1 file changed, 26 insertions(+)
> >
> > diff --git a/drivers/mmc/mtk-sd.c b/drivers/mmc/mtk-sd.c
> > index 7a4bdee7496..8f93e51599f 100644
> > --- a/drivers/mmc/mtk-sd.c
> > +++ b/drivers/mmc/mtk-sd.c
> > @@ -1989,6 +1989,30 @@ static const struct msdc_compatible mt8189_compat = {
> >       .enhance_rx = true,
> >  };
> >
> > +/* MT8188 and MT8195 should be fully compatible with MT8183
> > + * but currently dma is not working on these SoC.
> > + * For now, disable dma. Investigation needed.
> > + */
> > +static const struct msdc_compatible mt8188_compat = {
> > +     .clk_div_bits = 12,
> > +     .pad_tune0 = true,
> > +     .async_fifo = true,
> > +     .data_tune = true,
> > +     .busy_check = true,
> > +     .stop_clk_fix = true,
> > +     .enhance_rx = true,
> > +};
> > +
> > +static const struct msdc_compatible mt8195_compat = {
> > +     .clk_div_bits = 12,
> > +     .pad_tune0 = true,
> > +     .async_fifo = true,
> > +     .data_tune = true,
> > +     .busy_check = true,
> > +     .stop_clk_fix = true,
> > +     .enhance_rx = true,
> > +};
>
> These are identical to mt8189_compat, so we could reuse that instead of
> duplicating it two more times. MT8189 is in the same situation that it
> should work, but needs investigation.
>
> And actually mt8189_compat is also duplicate of mt7986_compat, so I probably
> shouldn't have added that one and just reused mt7986_compat.
>
> Another approach could be to revert the change that enabled DMA in mt8183_compat
> and add a new .compatible = "mediatek,mt8365-mmc" that has DMA enabled since
> that is the only board that has been tested where DMA is actually working.

Fair enough, let me do that
>
> > +
> >  static const struct udevice_id msdc_ids[] = {
> >       { .compatible = "mediatek,mt7620-mmc", .data = (ulong)&mt7620_compat },
> >       { .compatible = "mediatek,mt7621-mmc", .data = (ulong)&mt7621_compat },
> > @@ -2001,6 +2025,8 @@ static const struct udevice_id msdc_ids[] = {
> >       { .compatible = "mediatek,mt8516-mmc", .data = (ulong)&mt8516_compat },
> >       { .compatible = "mediatek,mt8183-mmc", .data = (ulong)&mt8183_compat },
> >       { .compatible = "mediatek,mt8189-mmc", .data = (ulong)&mt8189_compat },
> > +     { .compatible = "mediatek,mt8188-mmc", .data = (ulong)&mt8188_compat },
> > +     { .compatible = "mediatek,mt8195-mmc", .data = (ulong)&mt8195_compat },
> >       {}
> >  };
> >
> >
> > ---
> > base-commit: d31f96cac1e25153779c44f1fe014978f9b06032
> > change-id: 20260317-mt8188-mt8195-disable-mmc-disable-dma-b64499a6a47a
> >
> > Best regards,
>