[PATCH] arm: boards: Add support for MYIR MYD-AM335X Development Board

[Alexander Shiyan]

чт, 21 апр. 2022 г. в 11:30, Sascha Hauer <sha at pengutronix.de>:
> On Thu, Apr 21, 2022 at 10:57:33AM +0300, Alexander Shiyan wrote:
> > чт, 21 апр. 2022 г. в 10:35, Sascha Hauer <sha at pengutronix.de>:
> > >
> > > On Wed, Apr 20, 2022 at 12:53:22PM +0300, Alexander Shiyan wrote:
> > > > The MYD-AM335X Development Board designed by MYIR is a high-performance
> > > > ARM Evaluation Module (EVM) using the MYC-AM335X CPU module as the core
> > > > controller board. It is based on up to 1GHz Texas Instruments (TI)
> > > > Sitara AM335x family of ARM Cortex-A8 Microprocessors (MPUs) that deliver
> > > > high DMIPs at a low cost while also delivering optional 3D graphics
> > > > acceleration and key peripherals.
> > > >
> > > > Signed-off-by: Alexander Shiyan <eagle.alexander923 at gmail.com>
> > ...
> > > > +static struct omap_barebox_part myir_barebox_part = {
> > > > +     .nand_offset = SZ_128K,
> > > > +     .nand_size = SZ_512K,
> > > > +};
> > >
> > > Isn't this a bit too small? Putting a barebox into 128k seems very
> > > ambicous.
> >
> > The boot image (MLO) should not exceed 128 KB in size,
> > so I think this should be enough.
> > In any case this size is already specified for the boot partition
> > in kernel DTS for this board. :)
>
> Oh, I accidently misread nand_size as SZ_128K. Indeed it's SZ_512K which
> is small, but sufficient. Anyway, the BBU code assumes 4 eraseblocks for
> the four MLO images. That would be a nand_offset of SZ_512K also, which
> would then also match the upstream device tree for the board:
>
> &nand0 {
>         partition at 0 {
>                 label = "MLO";
>                 reg = <0x00000 0x20000>;
>         };
>
>         partition at 20000 {
>                 label = "boot";
>                 reg = <0x20000 0x80000>;
>         };
> };
>
> 512k is still very small nowadays. The images built with omap_defconfig
> are just a bit smaller than that.

Do you prefer that we fix this in the local overlay now,
or leave it as is until kernel DTS upstream changes?