>>>>> "Joakim" == Joakim Tjernlund <[EMAIL PROTECTED]> writes:
Joakim> We have noticed that the spi_mpc83xx.c driver is very slow, the gap Joakim> between words are huge. Joakim> So I started to optimise it and it still sucks. Joakim> However, if I poll the SPIE_NF SPIE_NE bits instead it works MUCH Joakim> better, like so: Yes, I've noticed the same. I get around ~5 times higher throughput with a simple polled loop in U-Boot compared to under Linux (66MHz clock). I've written it of as simply being a question of interrupt overhead (at 66MHz / 32bits we're talking over 2 million interrupts per second - E.G. only ~100 instructions between each!) Maybe it indeed makes more sense to use polling for high bitrates. -- Bye, Peter Korsgaard ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ spi-devel-general mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/spi-devel-general
