Hi Alessandro,
El Sat, Feb 06, 2010 at 08:53:30PM +0100 Alessandro Rubini ha dit:
I'm porting current u-boot to a board similar to EP9315A, so I'm using arm/master as a basis, as it includes the patches by Matthias Kaehlcke. I'm currently running from RAM (SKIP_LOWLEVEL_INIT), after setting up sdram and pll elsewhere (older vendor u-boot code, still to be ported).
"fix syscon_regs definition" is needed to access any software-locked syscon register from C code (e.g., in reset_cpu() and devicecfg used by me in patch 3).
you are right, i missed the gap between ChipID and SysCfg
"change calculation un early_udelay.h" is needed at least for eldk-4.2 (gcc-4.2.2), as without this patch it will use the stack before setting SP. Actually, we could use the ether buffer as a stack, if needed, but it's not really needed here.
i feared this could happen with different compiler versions, your fix certainly reduces the risk
"enable the uart in devicecfg register" prevents u-boot from freezing at least with SKIP_LOWLEVEL_INIT set, but I'm pretty sure lowlevel_setup assembly code doesn't enable the uart, either.
my ep9301 and ep9307 based boards for some reason boot with the uart enabled, though according to the datasheet it is disabled until enabled explicitly. therefore your fix is necessary for all cpus behaving as expected.
thanks a lot for your patches!