Troubles booting kernel with new imx8 board

[Sascha Hauer]

On Fri, May 26, 2023 at 08:46:40PM +1000, marc at cpdesign.com.au wrote:
> Hi all, 
> 
> I'm trying to get barebox going for a new imx8mp based board. I can 
> successfully power on and get to a barebox prompt etc and fiddle with gpios, 
> files on sd, memtest etc, but when booting to kernel it will hang. Note though 
> that the board boots ok with u-boot (using exact same kernel image).

Do you have an example crash dump? Does the kernel crash reproducibly or
randomly?

> 
> I'm trying to figure out what is different between booting via uboot and 
> barebox, I'm new to imx8 so have been going down a few rabbit holes...
> 
> Disabling various drivers (eg imx-cpufreq-dt) in the kernel will get past the 
> hang, but result in a crash later on in the boot sequence. Disabling that may 
> get further but will result in a crash somewhere else.
> My instinct is that its something to do with sdma, but a lot of this is still 
> a black box to me.

SDMA is only used in few devices like UART, I2C, SPI and sound. Apart from
sound all devices should work without SDMA, so you could disable the
driver.

> 
> Any hints or suggestions are very welcome! (I can give more info but didn't 
> want to dump everything straight away)

PMIC comes to my mind. Does it need some configuration?

Is the amount of memory detected correctly by barebox?

Sascha

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