[coreboot] and/or busybox issue with alix2c3 serial console
leroi.lists at gmail.com
Tue Nov 4 18:38:33 CET 2008
I'm experimenting with coreboot (v3) on alix2c3 and still can't get serial
console working. :( It stops right after kernel is done booting (I can see
coreboot, filo and kernel messages just fine). I use openWRT but tried also
another busybox based distribution (imedialinux) -- same problem. With
original tinybios no problem. At the same time I tried voyage linux (without
busybox) with corebooted alix and it has no such problem. It's obvious that
this problem cannot be identified as 100% busybox's (why then it works on
While digging coreboot sources I've noticed that uart initialization is done
twice for this board -- once in /southbridge/amd/cs5536/cs5536.c (based on
dts config) and second time in /mainboard/pcengines/alix2c3/stage1.c.
I tried playing with these (and /southbridge/amd/cs5536/stage1.c), disabling
one code or another, but no luck.
Tried to set MOD bits:
msr.lo = (1 << 4) | (1 << 5) | (1 << 6);
msr.hi = 0;
Also no luck.
Not enabling upper banks, however, makes uart appear in kernel as regular
16550A (and not as NS16550):
/* Bit 1 = DEVEN (device enable)
* Bit 4 = EN_BANKS (allow access to the upper banks)
//msr.lo = (1 << 4) | (1 << 1);
msr.lo = 1 << 1;
msr.hi = 0;
So... where should I go now? I'm really stuck. Begging for help...
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