Re: dvd kernelmodule: memory address problem

On Wednesday 14 April 2004 18:44, JockyW wrote:
> Thanks for your assistance Arthur,
>
> My simple dvd characterdevice works quite well. I rewrote the linux IRQ2
> handler to handle all dvd irqs (not just the cover int).
>
> But now I stumbled on a memory problem. My devicedriver uses a read buffer
> which is a 2048 bytes static char array. When I print the address, it sits
> on 0xC200EB24. That address doesn't work when I pass it to the DMA Memory
> Address Register. It is a strange address, because in "yagcd"
> http://www.gc-linux.org/docs/yagcd/chap4.html#sec4 it is written that
> uncached logical ram addresses run from 0xc0000000-0xc17fffff
>
> What kind of address translation should I apply to get the dma to work?

for a start, make sure the address you pass to the dma registers is 32 byte
aligned (didnt i write it somewhere? :=P)

gpz



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