[PATCH/RFC] ARM: dts: marzen: Add FLASH node

[Tudor Ambarus]

Hi, Geert!

Vignesh used to review CFI code, maybe he can intervene. I've never
worked with CFI, but I can try to help. I'll need more debug data though.

On 3/20/23 16:43, Geert Uytterhoeven wrote:
> Add a device node for the Spansion S29GL512N NOR FLASH on the Marzen
> development board.
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas at glider.be>
> ---
> Although the S29GL512N is a CFI FLASH, using "cfi-flash" instead of
> "mtd-rom" does not work:
>   1. Probing fails with "physmap-flash 0.flash: map_probe failed",

I would first try to understand why the probe fails.

>   2. The kernel crashes later in a spectacular way, cfr. the logs below.
> 
> U-Boot flinfo says:
> 
>     Bank # 1: CFI conformant flash (16 x 16)  Size: 64 MB in 512 Sectors
>       AMD Standard command set, Manufacturer ID: 0x01, Device ID: 0x227E
>       Erase timeout: 4096 ms, write timeout: 1 ms
>       Buffer write timeout: 3 ms, buffer size: 64 bytes
>       Sector Start Addresses:
>       00000000   RO   00020000        00040000   RO   00060000   RO   00080000
>       000A0000        000C0000        000E0000        00100000        00120000
>       00140000        00160000        00180000        001A0000        001C0000
>       ...
>       03FC0000        03FE0000
> 
>     Bank # 2: missing or unknown FLASH type
> 

Do you use "cfi-flash" compatible in u-boot and it works just fine? If
yes, I would try to understand what are the differences between the
probe paths from u-boot and linux. I know it doesn't help much, but we
should start from somewhere if we don't have any other feedback.

Cheers,
ta