On Thu, Sep 10, 2020 at 11:59 PM Brian Hutchinson <b.hutchman@...> wrote:

On Thu, Sep 10, 2020 at 05:22 AM, Fabio Estevam wrote:

Hi Otavio,

On Thu, Sep 10, 2020 at 9:09 AM Otavio Salvador
<otavio.salvador@...> wrote:

Could U-Boot load the correct dtb for the board revision?

Unfortunately, this cannot be determined in run-time.

When the sdcard is created, the u-boot environment has fdt_file defaulted to imx8mm-evk.dtb. I've not yet figured out how to override the recipe to specify which .dtb file should be used.

You can try to do something like this in your layer via creating a
u-boot-imx_%.bbapend:

patch_uboot_defconfig () {
sed -i -e '/^[ ]*CONFIG_DEFAULT_FDT_FILE[ ]*=/d' ${S}/configs/$1
echo 'CONFIG_DEFAULT_FDT_FILE="'$2'"' >>${S}/configs/$1
}

do_configure_prepend_imx8mmevk () {
patch_uboot_defconfig imx8mm_evk_defconfig imx8mm-evk-revb.dtb
}

NOTE: This is not the most clean solution on how to approach the
setting of U-Boot DTB and would (most probably) break reproducibility.
You can use it to see what should be changed, and try out if that
would solve the PCIe hang during boot. Also: "For verification
purposes ONLY!". :)

For sdcard boot, all of the .dtb's are on the FAT partition of the sdcard so it's easy enough to change the filename to use.

I use SPI NOR so I just have the .dtb file burned into a specific address so the name doesn't matter in that case.

Regards,

Brian

--
Regards,
Andrey.