[Arm-netbook] Allwinner F20 (sun3i) SD/MMC boot minimal 'blinking led' app

[Henrik Nordström]

ons 2012-05-16 klockan 17:13 +0200 skrev sysfwlab:

> My goal now is to build a bootable sd/mmc like for the A10.
> I try to use the "native" allwinner-u-boot  and mksunxiboot to create a mmc.
> I dont got anything on the serial port, but the device dont run the 
> app_demo.axf (Boot1) so i think it try to boot the mmc and probably 
> crash but It seem to be a good thing ?

You probably need other DRAM parameters on this device. The DRAM
parameters is currently hardcoded in the source.

> I found a kernel patch with mach-sun3i and mach-sun4i separated, and i 
> need probably confirm that sun3i got the same map registers of sun4i, 
> etc...i see mmc driver différence (SUN4I,SUN5I but no SUN3I...), etc... 
> but can someone already do this and got a working sun3i mmc u-boot ?

There is no stand-alone u-boot for sun3i.

Do you have a firmware file for your device?

> - Does anyone at AllWinner technology or not can confirm me i can boot 
> F20 from MMC ?

If it hangs when booting u-boot-mmc then it can boot from MMC.

> - For a minimal application which put a level on GPIO do i need to 
> init_clock() and clear the watch dog ?
> (Can i directly set the register to init the GPIO ?)

The over all structure is most likely similar to sun4i, but pins and
multiplex functions quite likely differ noticeably.

Regards
Henrik