Can't access mmc #0 on mt7623 when booted from external SD

[Michael Nazzareno Trimarchi]

Hi David

On Thu, Jun 18, 2020 at 9:21 PM David Woodhouse <dwmw2 at infradead.org> wrote:
>
> On Thu, 2020-06-18 at 16:52 +0100, David Woodhouse wrote:
> > So... whose bug is that? :)
>
> Looks like the pinctrl driver. This *ought* to work (with the caveat
> that I really ought to make two pinctrl setups and change between them
> according to the voltage, like the Linux DT and mtk-sd driver do).
>
> --- a/arch/arm/dts/mt7623n-bananapi-bpi-r2.dts
> +++ b/arch/arm/dts/mt7623n-bananapi-bpi-r2.dts
> @@ -133,12 +133,14 @@
>                                "MSDC0_DAT2", "MSDC0_DAT3",
> "MSDC0_DAT4",
>                                "MSDC0_DAT5", "MSDC0_DAT6",
> "MSDC0_DAT7";
>                         input-enable;
> -                       bias-pull-up;
> +                       drive-strength = <2>;
> +                       bias-pull-up = <3>;
>                 };
>
>                 conf-clk {
>                         pins = "MSDC0_CLK";
> -                       bias-pull-down;
> +                       drive-strength = <2>;
> +                       bias-pull-down = <3>;
>                 };
>
>                 conf-rst {
>
>
> But it doesn't work. Partly because the U-Boot mtk pinctrl driver
> doesn't support the R0 R1 bits encoded in that <3>, and partly because
> it doesn't *even* get pullup/pulldown right at all; it sets the bit in
> the GPIO_PULLSEL registers but *not* the PUPD bit in the correct
> register for MSDC and other pins.

So change them manually, make it work, You have the board. I don't
have any MediaTek board at the moment. Can you implement the missed part?

Michael



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| Michael Nazzareno Trimarchi                     Amarula Solutions BV |
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