Re: [PATCH v2] spl: Add generic SPL MTD loader support

[Sean Anderson <seanga2@gmail.com>]

On 2/25/26 19:08, Fabio Estevam wrote:
> Hi Sean,
> 
> On Wed, Feb 25, 2026 at 4:45 PM Sean Anderson <seanga2@gmail.com> wrote:
> 
>> Actually, I don't think this is correct. NAND devices have have multiple MTDs for each
>> CS, and SPI-NOR devices are UCLASS_SPI_FLASH and not UCLASS_MTD. So I think it's better
>> to do something like
>>
>>          mtd_probe_devices();
>>          switch (bootdev->boot_device) {
>>          case BOOT_DEVICE_NAND:
>>                  mtd = get_mtd_device_nm(CONFIG_SPL_MTD_NAND_NAME);
>>                  break;
>>          case BOOT_DEVICE_SPI:
>>                  mtd = get_mtd_device_nm(CONFIG_SPL_MTD_SPI_FLASH_NAME);
>>                  break;
>>          default:
>>                  mtd = ERR_PTR(-ENODEV);
>>                  break;
>>          }
>>          if (IS_ERR(mtd)) {
>>                  ret = PTR_ERR(mtd);
>>                  goto out;
>>          }
> ...
> 
>>> Actually, if CONFIG_SPL_NAND_SUPPORT is enabled then the native nand loader is compiled.
>>> Maybe we should add a separate Kconfig for it (CONFIG_SPL_NAND_LOAD) defaulting to
>>> SPL_NAND_SUPPORT. Then users can disable the "native" load method if they want to use MTD.
>>
>> I have a patch for this that I will try to send this week.
> 
> If you would like to prepare a patch for the generic SPL MTD loader,
> I'll be glad to test it.

I can try, but I can't promise I'll be done with it in any particular timeframe.

But TBH I don't think a spi_nand.c-style loader is the right way to do things when UBI exists.
Maybe Dinesh can comment, but I don't really see the point except if e.g. you are really short
on space in SPL, but not so much that you can't fit in MTD.

--Sean