> Dear sirs, > > I am trying to add a DMA transfer component to my driver on > linux 2.6 on a ppc 8541. Following the steps listed in the > reference manual, I write the SAR, SATR, DAR, DATR and BCR > registers before cycling the bit in the MR register to start > the transfer. > What is the DMA transfer mode? Is direct or chaining mode?
> The SR register though indicates a transfer error as soon as > I write the DAR register. Clearly I've gotten the mapping > wrong. I know what the address I am trying to write to in > kernel space is, what is unclear is what address the DAR > register is expecting. > Did you ioremap the DMA register space? The DAR register need the physical address Dave