setbat() in udbg_init_cpm() required to avoid driver lockup
daniel.ng1234 at gmail.com
Tue Jul 19 15:39:01 EST 2011
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
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