Re: [PATCH 2/2] arm64:?==?utf-8?q? dts: rockchip: Make eeprom read-only for Radxa ROCK 5A

[Dragan Simic]

On Monday, November 10, 2025 08:05 CET, FUKAUMI Naoki <naoki at radxa.com> wrote:
> On 11/10/25 14:17, Dragan Simic wrote:
> > On Monday, November 10, 2025 04:54 CET, FUKAUMI Naoki <naoki at radxa.com> wrote:
> >> Make EEPROM read-only as it may contain factory-programmed
> >> board-specific data.
> >>
> >> Fixes: 89c880808cff8 ("arm64: dts: rockchip: add I2C EEPROM to rock-5a")
> >> Signed-off-by: FUKAUMI Naoki <naoki at radxa.com>
> >> ---
> >>   arch/arm64/boot/dts/rockchip/rk3588s-rock-5a.dts | 1 +
> >>   1 file changed, 1 insertion(+)
> >>
> >> diff --git a/arch/arm64/boot/dts/rockchip/rk3588s-rock-5a.dts b/arch/arm64/boot/dts/rockchip/rk3588s-rock-5a.dts
> >> index 19a08f7794e67..ae7b03488c9e7 100644
> >> --- a/arch/arm64/boot/dts/rockchip/rk3588s-rock-5a.dts
> >> +++ b/arch/arm64/boot/dts/rockchip/rk3588s-rock-5a.dts
> >> @@ -254,6 +254,7 @@ eeprom: eeprom at 50 {
> >>   		compatible = "belling,bl24c16a", "atmel,24c16";
> >>   		reg = <0x50>;
> >>   		pagesize = <16>;
> >> +		read-only;
> >>   	};
> >>   };
> > 
> > I've checked the board schematic and making this BL24C16 chip
> > read-only makes sense to me.  However, I think that the patch
> > description should be expanded to contain a better description
> > of what might be found in the chip, such as a factory-programmed
> > MAC address.  Also, providing a link to the board schematic, as
> > a reference, would be a good idea.
> 
> ----
> arm64: dts: rockchip: Make eeprom read-only for Radxa ROCK 3C/5A/5C
> 
> Make the EEPROM[1][2][3] read-only. Board-specific data written to the 
> EEPROM at the factory includes, but is not limited to, the SKU (~ 
> product name), BOM version (~ board version), and MAC address.

Thanks for the improvements!  I'd just suggest that the opening
sentence above is rewritten like this:

  Make the BL24C16 EEPROM chips found on Radxa ROCK 3C, 5A and
  5C SBCs [1][2][3] read-only, because they contain factory-
  programmed data that isn't supposed to be modified by the end
  users.

This would also be perfect timing for Radxa to officially release
the layout of the board-specific data that goes into these EPROM
chips, so the data can actually be used.

> [1] 
> https://dl.radxa.com/rock3/docs/hw/3c/v1400/radxa_rock_3c_v1400_schematic.pdf 
> p.13
> [2] https://dl.radxa.com/rock5/5a/docs/hw/radxa_rock5a_V1.1_sch.pdf p.19
> [3] 
> https://dl.radxa.com/rock5/5c/docs/hw/v1100/radxa_rock_5c_schematic_v1100.pdf 
> p.18
> ----
> 
> > With these remarks addressed in a v2, please feel free to include
> > 
> > Reviewed-by: Dragan Simic <dsimic at manjaro.org>
> > 
> > Additionally, it would make sense to squash this patch and your
> > other patch that addresses the ROCK 5C together.  They're very
> > similar and having them together in a single commit might actually
> > help the people browsing the repository understand it better.
> 
> I'll drop eeprom patch from ROCK 5C v7 patch series, and squash eeprom 
> patches for ROCK 3C/5A/5C.

Thanks!