kernel boot stuck at udbg_putc_cpm()
Shawn Jin
shawnxjin at gmail.com
Mon Jul 12 16:26:45 EST 2010
> You're probably getting to the point where udbg is disabled because the
> real serial driver is trying to take over -- and something's going
> wrong with the real serial port driver. Check to make sure the brg
> config is correct (both the input clock and the baud rate you're trying
> to switch to). Commenting out the call to cpm_set_brg can be
> a quick way of determining if that's the problem.
It seems that the last CP command RESTART_TX never completes in the
cpm_uart_console_setup(). I commented out the writes to brgc1 in
cpm_setbrg() in cpm1.c so that the brgc1 value stays the same as
previously set.
The registers related to SMC1 are dumped below before the last
RESTART_TX command. The CPCR was 0x0090. But after issuing the
RESTART_TX command the CPCR kept at 0x0691. Is there any other obvious
reason for CPM not completing the command? It got to be something
related to the settings.
BDI>rd cpcr
cpcr : 0x0090 144
BDI>rd rccr
rccr : 0x0001 1
BDI>rd rmds
rmds : 0x00 0
BDI>rd rctr1
rctr1 : 0x0000 0
BDI>rd rctr2
rctr2 : 0x0000 0
BDI>rd rctr3
rctr3 : 0x802e -32722
BDI>rd rctr4
rctr4 : 0x802c -32724
BDI>rd rter
rter : 0x0000 0
BDI>rd rtmr
rtmr : 0x0000 0
BDI>rd brgc1
brgc1 : 0x00010618 67096
BDI>rd smcmr1
smcmr1 : 0x4823 18467
BDI>rd smce1
smce1 : 0x00 0
BDI>rd smcm1
smcm1 : 0x00 0
Thanks,
-Shawn.
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