Our USB Device Controller (UDC) driver seems to get stuck in a loop waiting
for the CPM Command Register to indicate that the CPM has finished executing
a command. (It should do this by setting the cpmcr 'Command Done' bit).

This only happens if I disable the 'Early Debug' Kernel Hacking .config
parameter. If Early Debug is enabled, then the problem goes away.

I've narrowed it down to this line in udbg_init_cpm(void):

setbat(1, 0xf0000000, 0xf0000000, 0x40000, PAGE_KERNEL_NCG);

-without this line, the driver gets stuck in the loop.

Can anyone suggest why?

Also, what undesireable effects might there be of keeping the above call to
setbat()?

System:
-MPC8272 (CPM2)
-Kernel 2.6.30.3

Cheers,
Daniel

-- 
View this message in context: 
http://old.nabble.com/setbat%28%29-in-udbg_init_cpm%28%29-required-to-avoid-driver-lockup-tp32088424p32088424.html
Sent from the linuxppc-dev mailing list archive at Nabble.com.

_______________________________________________
Linuxppc-dev mailing list
[email protected]
https://lists.ozlabs.org/listinfo/linuxppc-dev

Reply via email to