Re: [U-Boot] Timer implementations

26 Oct 2010


      Dear Nishanth Menon,
In message 4CC6F23A.2040608@ti.com you wrote:
...
...
No. This code is always wrong. Please fix it as described.
Apologies on being a dudhead, I suppose you mean the following:
ulong start;
start = get_timer(0);
while (!(readl(&mmc_base->stat) & CC_MASK)) {
         if (get_timer(start) > usec2ticks(MAX_RETRY_US)) {
                 printf("%s: timedout waiting for cc2!\n", __func__);
                 return;
         }
}
would this be better?
No, not at all, as get_timer() returns milliseconds, not ticks.
You probably want something like:
ulong start = get_timer(0);
while (!(readl(&mmc_base->stat) & CC_MASK)) {
    	if (get_timer(0) - start >= MAX_RETRY_US/1000) {
    		printf(...);
    		return;
    	}
    	udelay(100);
    }
or such.
Best regards,
Wolfgang Denk
-- 
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