boot problem w/ barebox

[Uwe Kleine-König]

On Sat, Sep 09, 2017 at 11:01:34AM +0200, Enrico Weigelt, metux IT consult wrote:
> Hi folks,
> 
> 
> I've got a really strange booting problem on an phycore-imx6
> based board (pretty much the same as mira):
> 
> * barebox v2017.06.1-phy2 comes up properly, but cant boot
>   the kernel (v4.13) - just hangs w/o any output (not even
>   uncompression message)
> * putting the kernel manually into the factory-image (sdcard)
>   w/ old 2015 barebox boots the kernel
> * w/ DEBUG_LL + earlyprintk it doesn't even does that, just
>   hangs like w/ new barebox
> 
> 
> Here's the last output I've got: (added few more debug outputs)
> 
> > Loading ARM Linux zImage '/mnt/mmc/boot/zImage'
> > Loading devicetree from '/mnt/mmc/boot/imx6q-phytec-mira-rdk-emmc.dtb'
> > Updating DT commandline:  console=ttymxc1,115200n8 root=/dev/mmcblk0p2
> rootwait rw earlyprintk=1
> > DT commandline:  console=ttymxc1,115200n8  root=/dev/mmcblk0p2 rootwait rw
> earlyprintk=1
> > booting kernel with devicetree
> > start_linux: kernel entry point: 12000000
> >                            dtb: 18000000
> >                           swap: 0
> >                           arch: 0
> > shutting down barebox
> 
> My first suspicion was zero'ed DT memory node (which OTOH doesn't
> explain why earlyprintk doesn't work), but fixing that didn't help.
> 
> Could there be any vital low-level init missing in the new bbx ?
> Maybe the entry point correct ?
> 
> Any ideas where I could have a deeper look at ?

Try adding a #define DEBUG in linux-4.13/arch/arm/boot/compressed/head.S
and make sure enabled DEBUG_LL and selected the right UART in your
.config.

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |