On Dec 17, 2009, at 11:44 AM, Dan Williams wrote: > Ira W. Snyder wrote: >> Yes, I have used the device_prep_dma_interrupt() functionality quite a >> while back. However, I found it to be pretty much useless. > > The specific case it is needed for Talitos/raid is a channel switch > interrupt. The interrupt causes the cleanup operation to be run which will > kick off any pending dependent operations on the xor channel. In the raid > case we only have callbacks at the end of a chain, so we need the interrupt > to kick the engine in an operation chain like xor->copy->xor->callback.
Ok, I'm still confused as to how the DMA interrupt interacts with the Talitos/raid side of things. The should be completely independent (separate interrupts, separate IP blocks). - k _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
