Dear Reinhard Meyer,
In message 4D3D2F34.6020903@emk-elektronik.de you wrote:
Dear all,
its quite funny to see how we go around in circles here, this proposal of Albert now is quite close to my original proposal. Only that I factored the ms_to_ticks AND the comparison into the timer calls:
u64 timer_setup(u32 timeout_in_ms) { return get_ticks() + ms_to_ticks(timeout_in_ms); }
No. I said this severaltimes before, and I repeat it here one other time: I do not want to see such a function. There nothing to be done to "set up a timer".
/* * convert the unsigned difference to signed, to easyly * check for "carry". In assembly we could just do a BCC * after the subtraction to see whether get_ticks() * has passed ahead of endtime. */ return (signed)(endtime - get_ticks()) < 0;
Are you sure this is really working? Why do you insist on this approach instead of using the proven to be correct way to write this?
u32 start = get_timer(); /* start time, in ticks */
No. I do not see any reason to change existing interfaces.
If ticks are wanted, then use get_ticks(). And deal with the overhead or 64 bit arithmetics.
But in general code I prefer get_timer() - milliseconds, u32.
Best regards,
Wolfgang Denk