Re: [PATCH] arm64: dts: rockchip: Assign a fixed index to mmc devices on rk3399-roc-pc boards.
From: Chen-Yu Tsai
Date: Wed Nov 04 2020 - 11:04:10 EST
On Wed, Nov 4, 2020 at 11:55 PM Heiko Stübner <heiko@xxxxxxxxx> wrote:
>
> Am Mittwoch, 4. November 2020, 16:42:01 CET schrieb Doug Anderson:
> > Hi,
> >
> > On Wed, Nov 4, 2020 at 2:51 AM Heiko Stübner <heiko@xxxxxxxxx> wrote:
> > >
> > > Hi Markus,
> > >
> > > Am Mittwoch, 4. November 2020, 10:49:45 CET schrieb Markus Reichl:
> > > > 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/
> > > >
> > > > Signed-off-by: Markus Reichl <m.reichl@xxxxxxxxxxxxx>
> > > > ---
> > > > arch/arm64/boot/dts/rockchip/rk3399-roc-pc.dtsi | 5 +++++
> > > > 1 file changed, 5 insertions(+)
> > > >
> > > > diff --git a/arch/arm64/boot/dts/rockchip/rk3399-roc-pc.dtsi b/arch/arm64/boot/dts/rockchip/rk3399-roc-pc.dtsi
> > > > index e7a459fa4322..bc9482b59428 100644
> > > > --- a/arch/arm64/boot/dts/rockchip/rk3399-roc-pc.dtsi
> > > > +++ b/arch/arm64/boot/dts/rockchip/rk3399-roc-pc.dtsi
> > > > @@ -13,6 +13,11 @@ / {
> > > > model = "Firefly ROC-RK3399-PC Board";
> > > > compatible = "firefly,roc-rk3399-pc", "rockchip,rk3399";
> > > >
> > > > + aliases {
> > > > + mmc0 = &sdmmc;
> > > > + mmc1 = &sdhci;
> > > > + };
> > > > +
> > >
> > > Any reason for this odering?
> > >
> > > I.e. some previous incarnations had it ordered as (emmc, mmc, sdio).
> > > This is also true for the ChromeOS out-of-tree usage of those, the
> > > rk3399 dts in the chromeos-4.4 tree also orders this as sdhci, sdmmc, sdio.
> > >
> > > And I guess a further question would be when we're doing arbitary orderings
> > > anyway, why is this not in rk3399.dtsi ;-) ?
> >
> > Though I personally like the idea of eMMC, which is typically
> > built-in, as being the "0" number, I'm personally happy with any
> > numbering scheme that's consistent. Ordering them by base address is
> > OK w/ me and seems less controversial. That seems like it could go in
> > rk3399.dtsi and then if a particular board wanted a different order
> > they could override it in their board file.
>
> Yep that sounds sensible and ordering by base address at least is one
> "simple" type of order without too much explanation needed.
>
> So I guess we'd get a sdio + sdmmc + sdhci ordering
>
>
> @Markus: if nobody else complains, can you do a "simple" rk3399.dtsi
> change with that please?
Please also fix the LED triggers. :)
> > The downside of putting
> > in rk3399 is that boards that don't have all SD/MMC interfaces enabled
> > would definitely get a new number compared to old kernels, but
> > hopefully this is the last time?
>
> With that new asynchronous mmc-probe-thingy in 5.10 that "caused" this,
> it sounds like everything gets a new number anyway ;-) .
Yup.