Re: [PATCH] ARM: dts: exynos: Assign a fixed index to mmc devices on ODROID XU3/4 boards

[Markus Reichl]

Hi Marek,

Am 04.11.20 um 13:24 schrieb Marek Szyprowski:
> Hi Markus,
>
> On 04.11.2020 11:08, Markus Reichl wrote:
> > Recently introduced async probe on mmc devices can shuffle block IDs.
> > Pin them to fixed values to ease booting in evironments where UUIDs
> > are not practical. Use newly introduced aliases for mmcblk devices from [1].
> >
> > [1]
> > https://patchwork.kernel.org/patch/11747669/
>
> Wow, this is a long standing issue, called by others 'a feature'. Good
> that this has been finally solved.
>
> > Signed-off-by: Markus Reichl <m.reichl@xxxxxxxxxxxxx>
> > ---
> >   arch/arm/boot/dts/exynos5422-odroidxu3-common.dtsi | 5 +++++
> >   1 file changed, 5 insertions(+)
> >
> > diff --git a/arch/arm/boot/dts/exynos5422-odroidxu3-common.dtsi b/arch/arm/boot/dts/exynos5422-odroidxu3-common.dtsi
> > index e35af40a55cb..91d2840ac8ca 100644
> > --- a/arch/arm/boot/dts/exynos5422-odroidxu3-common.dtsi
> > +++ b/arch/arm/boot/dts/exynos5422-odroidxu3-common.dtsi
> > @@ -13,6 +13,11 @@
> >   #include "exynos5422-odroid-core.dtsi"
> >   
> >   / {
> > +	aliases {
> > +		mmc0 = &mmc_2;
> > +		mmc1 = &mmc_0;
>
> Frankly, I would keep the MMC numbers the same as in u-boot and
> datasheets. 0 for the build-in eMMC and 2 for the SD-card. This would be
> much more natural. On the other hand, I would agree to do it differently
> only on Odroid HC1/HD2/MC1, which don't have build-in eMMC - just use 0
> there for the SD-card.

This would break present and long standing  boot ordering in mainline, which is
mmcblk0 = SD-card and
mmcblk1 = eMMC

Still desired?
> > +	};
> > +
> >   	gpio-keys {
> >   		compatible = "gpio-keys";
> >   		pinctrl-names = "default";
>
> Best regards

Gruß,
--
Markus Reichl