Hi,
Is there anyway to restrict the returned bus address(dma address) from dma_poll_alloc to < 4GB ?
The function returns a dma address(of type dma_addr_t). Is there anyway I can ensure to restrict it to < 4B address.
I guess we can do that in pci_alloc_consistent as by default it returns 32bit address.
with regards,
Anil
On Wed, Nov 12, 2008 at 02:14:24PM -0800, Anil kumar wrote:
> Is there anyway to restrict the returned bus address(dma address) from dma_poll_alloc to < 4GB ?
> The function returns a dma address(of type dma_addr_t). Is there anyway I can ensure to restrict it to < 4B address.
> I guess we can do that in pci_alloc_consistent as by default it returns 32bit address.
dma_pool_alloc (as described in the documentation ...) allocates memory
using dma_alloc_coherent(). As long as you've set the coherent mask
to 32-bit (or left it alone, since it's 32-bit by default ...), you'll
get 32-bit dma addresses back.
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