[PATCH v2 4/6] board: starfive: support Milk-V Mars board

[Leo Liang]

Hi Heinrich,

On Wed, Mar 27, 2024 at 12:03:01PM +0100, Heinrich Schuchardt wrote:
> [EXTERNAL MAIL]
> 
> On 24.03.24 16:00, Aurelien Jarno wrote:
> > On 2024-03-21 19:11, Heinrich Schuchardt wrote:
> > > The differences between the Milk-V Mars board and the VisionFive 2 board
> > > are small enough that we can support both using the same U-Boot build.
> > > 
> > > * The model and compatible property are taken from proposed Linux patches.
> > > * The EEPROM is atmel,24c02 according to the vendor U-Boot.
> > > * The second Ethernet port is not available.
> > 
> >  From the device tree that have been submitted to the kernel [1] it seems
> > another difference is that there is a CD gpio for mmc1.
> 
> Yes, the Mars board has
> 
>     cd-gpios = <&sysgpio 41 GPIO_ACTIVE_LOW>;
> 
> while the VisionFive 2 has
> 
>    broken-cd;
> 
> We could add the cd-gpios to the VF2 dts and then set broken-cd in
> spl_fdt_fixup_*().
> 
> What I would really like to understand from the reviewers is if the
> approach with patching the device-tree is what we are targeting for.
> 
> Or should we try to keep the device-trees in sync with Linux, package
> all JH7110 device-trees into the FIT image and in SPL choose the
> device-tree from the fit image and only patch the memory size.
> 
> The device-tree for the Milk-V CM module differs a lot in GPIO routing.
> I am not sure that patching the VF2 device-tree is future proof.

I think we could patch the VF2 device-tree currently with this few differeces,
and create a new device tree for Milk-V Mars CM module if patching the VF2 device tree
is too much of an effort.

Does this sound reasonable ?
Do you have any preference over which scheme we should use ?

Best regards,
Leo

> 
> Best regards
> 
> Heinrich
> 
> 
> > 
> >  From the schematics, it also seems that the usb0 port is not in
> > peripheral mode, but in host mode. That said on the submitted kernel
> > device tree it seems simply disabled.
> > 
> > Aurelien
> > 
> > [1] https://lore.kernel.org/linux-kernel/20240131132600.4067-2-jszhang@kernel.org/T/
> > 
>