On Fri, May 14, 2010 at 01:47:21PM +0200, Rolf Eike Beer wrote:
...
> The trick is like this:
>
> pci_set_dma_mask(pdev, DMA_BIT_MASK(32))
> pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64))
I think this is reversed. The original problem was:
"my PCIe device supports 64-bit DMA for data, but only 32-bit
addresses for fetching descriptors from host memory."
So you want:
pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32))
pci_set_dma_mask(pdev, DMA_BIT_MASK(64))
Quite a few older "64-bit" PCI and PCI-X devices have this same limitation.
However, ISTR that PCI-E spec *requires* 64-bit addressing support for
all DMA accesses. If I've got that correct, this device can not be
considered PCI-E compliant even if it works fine with linux.
hth,
grant
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
