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

[Michael Nazzareno Trimarchi]

On Tue, Jun 16, 2020 at 6:57 PM David Woodhouse <dwmw2 at infradead.org> wrote:
>
> On Tue, 2020-06-16 at 18:21 +0200, Michael Nazzareno Trimarchi wrote:
> > Hi David
> >
> > On Tue, Jun 16, 2020 at 6:16 PM David Woodhouse <dwmw2 at infradead.org> wrote:
> > >
> > > The Banana Pi R2 bootloader will load U-Boot from either the internal
> > > eMMC, or the external SD card if the latter is present.
> > >
> > > If booted from the eMMC (and an SD card is subsequently inserted), both
> > > work from U-Boot. Both also work from Linux, whichever device is booted
> > > from.
> > >
> > > If booted from SD, the internal eMMC cannot be accessed from U-Boot.
> > > This makes it slightly difficult for me to write a U-Boot script which
> > > installs OpenWRT from the SD card to the internal eMMC...
> >
> > I'm thinking that bootrom do the right job for you when both are working.
>
> Yes. It does seem likely that when loading U-Boot from the eMMC, the
> preloader is initialising it for us. But when the preloader loads
> U-Boot from the SD card, it possibly doesn't initialise the eMMC
> controller at all.
>
> The Linux driver does cope with this, and drives the internal eMMC.
> Perhaps there's just some init code missing from the U-Boot mtk-sd
> driver?

what dts are you using and config? I don't find Banana PI R2

Micheal

>
>
>


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| Michael Nazzareno Trimarchi                     Amarula Solutions BV |
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