Re: [PATCH] arm64: dts: Add/fix /memory node unit-addresses

Diogo Ivo
2024-07-01T14:40:01Z

Hi Thierry,

On Fri, Jun 28, 2024 at 05:06:10PM GMT, Thierry Reding wrote:
> On Tue, Apr 30, 2024 at 02:18:54PM GMT, Rob Herring (Arm) wrote:
> [...]
> > diff --git a/arch/arm64/boot/dts/nvidia/tegra210-smaug.dts b/arch/arm64/boot/dts/nvidia/tegra210-smaug.dts
> > index 9ebb7369256e..2e5b6b2c1f56 100644
> > --- a/arch/arm64/boot/dts/nvidia/tegra210-smaug.dts
> > +++ b/arch/arm64/boot/dts/nvidia/tegra210-smaug.dts
> > @@ -25,7 +25,7 @@ chosen {
> > stdout-path = "serial0:115200n8";
> > };
> >
> > - memory {
> > + memory@80000000 {
> > device_type = "memory";
> > reg = <0x0 0x80000000 0x0 0xc0000000>;
> > };
>
> [trimming the recipient list and adding Diogo]
>
> Sorry I just noticed this as I was doing a cleanup path of patchwork.
>
> For tegra210-smaug, unfortunately we can't do this. The problem is that
> the firmware for this device looks for a hard-coded /memory device when
> updating with the proper memory size and this firmware can't always be
> updated.
>
> Diogo, you're one of the few remaining people that I know of that still
> use this device (with an upstream kernel). Do you have any more details
> about this? Is there any way the firmware can be safely updated on these
> devices?

To be honest I am not quite sure. I do know that at least there is a part
of the firmware that is locked down and cannot be updated easily, as you
have to disconnect a ribbon cable inside of the device. Do you know of
any firmware updates for this device? Currently I am not aware of any.

Diogo