Re: [PATCH 1/2] arm: dts: Add override for RB1

[Sumit Garg <sumit.garg@kernel.org>]

On Tue, Apr 08, 2025 at 02:17:29PM +0200, Caleb Connolly wrote:
> 
> 
> On 4/7/25 15:28, Sumit Garg wrote:
> > From: Sumit Garg <sumit.garg@oss.qualcomm.com>
> > 
> > Add U-Boot override for RB1 to for USB in host mode as OTG mode isn't
> > supported. Also, disable sdhc_2 as it's currently not supported, sdhc_1
> > works fine though.
> > 
> > Signed-off-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
> > ---
> >   arch/arm/dts/qrb2210-rb1-u-boot.dtsi | 11 +++++++++++
> >   1 file changed, 11 insertions(+)
> >   create mode 100644 arch/arm/dts/qrb2210-rb1-u-boot.dtsi
> > 
> > diff --git a/arch/arm/dts/qrb2210-rb1-u-boot.dtsi b/arch/arm/dts/qrb2210-rb1-u-boot.dtsi
> > new file mode 100644
> > index 00000000000..1e136ee405a
> > --- /dev/null
> > +++ b/arch/arm/dts/qrb2210-rb1-u-boot.dtsi
> > @@ -0,0 +1,11 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +
> > +/* This is usually OTG but U-Boot doesn't support that properly */
> > +&usb_dwc3 {
> > +	dr_mode = "host";
> > +};
> > +
> > +/* SDHC_2 isn't supported in U-Boot as of now */
> 
> I'd rather avoid disabling this here, I guess it's just missing clocks and
> regulators which doesn't justify modifying DT. An error that mmc1 couldn't
> be enabled seems fine to me?

I totally echo with your thinking that we should avoid modifying DT but
at the same point we shouldn't enable peripherals in U-Boot which throws
errors. It's also possible that U-Boot misconfiguring mmc1 which might
turn as a problem for later stages.

I have been totally working with a remote lab to fix issues on RB1. I
will soon get one on my desk then I will be able to fix mmc1 too.

-Sumit

> > +&sdhc_2 {
> > +	status = "disabled";
> > +};
> -- 
> Caleb (they/them)
>