[U-Boot-Users] OCOTEA get_timer() bug
awozniak at mc.com
Mon Mar 28 21:25:38 CEST 2005
I found this bug a while ago and have finally gotten around to looking
at it because I needed its service.
In previous posts to this email list, Wolfgang had mentioned that the
"time unit" returned by get_timer() is 1 msec. Close examination of
interrupt_init_cpu() at cpu/ppc4xx/interrupts.c suggests a timer
interval setup of 10 msec!
A quick experiment via u-boot application, shows this to be true:
tic = get_timer(0);
udelay(2000000); /* 2sec delay so that I can "see" it */
toc = get_timer(0);
printf("...toc\n %d %d\n", tic, toc);
200 = delta
2sec/200 = 10msec time unit from get_timer()
I've tested the following and propose it as a fix, replace this:
val = gd->bd->bi_intfreq/100; /* 10 msec */
val = gd->bd->bi_intfreq/1000; /* 1 msec */
I've also tested some of the network related functions to insure that no
timeout conditions have appeared.
I want to post this patch but would prefer a code review from those that
are more familiar with get_timer() use within the OCOTEA codebase.
Sorry for the long post, Andrew
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