Need help with booting from SPI Flash

[Quentin Schulz]

Hi Matwey,

On 2/24/25 10:57 AM, Matwey V. Kornilov wrote:
> Hi,
> 
> I have an Allwinner based board with manually soldered 16MB SPI Flash.
> I am trying to place u-boot into the flash and need some help so far.
> I have already updated the board DTS file and checked that the Linux
> kernel provides me with a /dev/mtd0 device which is writable and
> readable.
> 
> I enable the following config options additionally to the board configuration:
> CONFIG_SPL_SPI_FLASH_SUPPORT,
> CONFIG_SPL_SPI,
> CONFIG_SPL_MTD_SUPPORT,
> CONFIG_SPL_SPI_FLASH_MTD,
> CONFIG_SPL_SPI_LOAD.

Make sure the driver for the SPI controller on your SoC also is enabled 
in SPL.

> I am not sure that I chose every relevant option.
> 
> However, I see the following message from the bootloader:
> 
> U-Boot SPL 2024.01-rc1-45362-g94a35b52f78-dirty (Feb 24 2025 - 12:43:35 +0300)
> mxstatus=0xc0408000 mhcr=0x0000010b mcor=0x00000003 mhint=0x00004000
> Trying to boot from SPI
> Invalid bus 0 (err=-19)
> SPI probe failed.
> SPL: failed to boot from all boot devices
> ### ERROR ### Please RESET the board ###
> 
> Are there any obvious things I missed? How could I debug this?
> 

Can you check your SPL DTB has the SPI bus and flash node?

dtc -I dtb -O dts spl/u-boot-spl.dtb

If not, you're missing a <your-board>-u-boot.dtsi in arch/arm/dts/ where 
the SPI bus (and most of what it is needed to enable the controller, 
power, clock, pinmux, ...) and the flash node has the appropriate 
bootph- property. I believe it should be bootph-pre-ram for SPL, 
according to scripts/Makefile.lib (fdtgrep_props).

Cheers,
Quentin