Dear U-Boot hackers,
I am trying to let U-Boot work with my archos g9 (omap4430 based-tablet).
I tried with u-boot-2012.07.tar.bz2
So far I succeeded in booting an MLO and u-boot.img from a FAT SD-card after issuing a warm-reboot in a rooted android.
But then I have very random results when loading a file in memory and running a "go 0x82000000".
I compiled without thumb and had to change the base address (0x40300000).
I modified memory settings, based on pandaboard (also a OMAP4430 device). (I don't know if all the settings are correct or not.)
I did not modify anything else, especially MUX settings and clocks.
But since the device successfully accesses the sd-card and load files from there I guess things are "not too bad". (barebox fails at that point)
To test things, I added a simple function "reboot" to U-Boot that issues a warm-reboot after setting good values for registers in the SAR RAM zone. That zone is not touched by android and I then can read /dev/mem in linux to see the data there. So I can see values from U-Boot. A bit cumbersome but works fine.
And to boot from the sd-card, I made a program "reboot-sd", run as root in android that does the same, but in linux, not U-Boot. (I hope I am clear.)
From where I am, I am a bit lost. Calling "reboot" in U-Boot
reboots okay. But creating a uImage file containing the same code, loading it with fatload at 0x82000000 and doing a "go" there fails (ie. the device does not reboot). Why? I can see that it is loaded okay. So why jumping there fails. To be correct, in fact it sometimes works, but most of the time fails. Very random and strange behavior.
So, I ask for some help. Where to look from that point? Is the MUX thing an issue? Or maybe the uImage code runs fine but the reboot it is supposed to do is not done for whatever reason?
So it could be: 1 - problem with how I hacked U-Boot 2 - problem with the payload (uImage simply does a warm reboot for now)
The ultimate goal is to load the linux kernel.
I apologize by advance if I describe things badly, but I don't really know what to do now...
Thanks for your help, Cédric.