[U-Boot] [PATCH v4 0/9] mmc: sunxi: Enable DM_MMC

[Jagan Teki]

On Wed, Jan 30, 2019 at 5:17 PM Andre Przywara <andre.przywara at arm.com> wrote:
>
> On Wed, 30 Jan 2019 11:16:07 +0100
> Tomas Novotny <tomas at novotny.cz> wrote:
>
> Hi,
>
> > On Tue, 29 Jan 2019 15:54:07 +0000, Andre Przywara
> > <andre.przywara at arm.com> wrote:
> > > This series gathers all remaining patches we need to enable DM_MMC
> > > for Allwinner boards. It relies on the clock gates framework
> > > already merged, and adds the respective gates and resets for each
> > > SoC. It then teaches the sunxi MMC driver to use the clock
> > > framework for those reset and gates clocks. The "mod clock",
> > > responsible for setting the actual interface speed, is still
> > > handled in the MMC driver, as the DM_CLK part of that is not ready
> > > yet (and is not trivial). This allows to turn on DM_MMC, and gets
> > > rid of the doomsday warning message every Allwinner board was
> > > blessed with for a while.
> > >
> > > This series is available at:
> > > https://github.com/apritzel/u-boot/commits/sunxi-dm-gates
> >
> > I've briefly tested that branch on A83t mainlined tablet (TBS A711).
> > I was able to boot from SD card and eMMC.
> >
> > Just noticed that message:
> > MMC:   Device 'mmc at 1c11000': seq 1 is in use by 'mmc at 1c10000'
> > mmc at 1c0f000: 0, mmc at 1c10000: 2, mmc at 1c11000: 1
> > I guess that this is the mmc1/2 renaming stuff?
>
> I think so. So is this just a warning, and it continues anyway and
> works?
>
> TBH, I don't like this patch 9/9 very much, I actually believe relying
> on this numbering scheme in /aliases is something odd and fragile.
> Especially since Linux (and other OSes) seem to get away without it.
>
> For MMC, can't we just enumerate them dynamically? AFAIU the MMC driver
> would not probe a block device successfully on an SDIO device, would it?
>
> But for the sake of having something working, I am fine with the patch,
> at least on a for-now basis.

It's not a simple think that 9/9 fix is for,It's something big like
w/o that we can't get the default env and fastboot devices because we
always assign mmc1 for these purposes and indeed mmc1 is SDIO for DT
enumeration.