All, This isn't really a Linux PPC question, but this is the smartest mailing list I know for asking PPC hardware questions, so here goes.
We're using an MPC8308 and want to use the DMA engine to move data in and out of an FPGA hanging on the local bus. Our bandwidth/local bus burden calculations were done assuming that we could use bursting. So I've setup a UPM to do single beat and burst reads/writes. I've also configured my DMA TCD to use a data transfer size of 32-bytes when accessing the FPGA. The problem I'm having is I can't seem to get the UPM to ever trigger the burst write sequence using the DMA. Single beat reads and writes work okay, but no bursting. In fact, the only thing I've been able to find in the manual that causes a burst transaction is a cache line miss, which is wholly in the purview of the core and really does me no good. Does anyone know of any way (short of issuing a run command to the UPM via MxMR) to force a burst transaction on the 8308? Am I just being dumb and missing something totally fundamental? Thanks. Bruce _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev