William Rogers

DMA transfer size limited on MPC8272

Discussion created by William Rogers on Apr 6, 2007
Latest reply on May 12, 2009 by William Rogers
I am DMA'ing from 60x memory to PCI memory and from PCI memory to 60x memory in a Linux device driver using the MPC8272 processor.  The DMA completes but the logic analyzer shows that the DMA is broken up into a series of 32 byte (8 dword) transfers, no matter what the byte count is in the segment descriptor.  Shouldn't I be able to do the transfer in a single DMA transfer?  If so, how?  Is there a register setting I am missing?

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