Messages in this thread | | | Date | Sun, 24 May 2009 00:59:26 +0200 | Subject | Re: [PATCH V2 2/3] powerpc: Add support for swiotlb on 32-bit | From | Leon Woestenberg <> |
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Hello,
On Sat, May 23, 2009 at 1:55 AM, Jeremy Fitzhardinge <jeremy@goop.org> wrote: > Ian Campbell wrote: >> >> On Thu, 2009-05-21 at 14:27 -0400, Becky Bruce wrote: >> >>> >>> I can work with that, but it's going to be a bit inefficient, as I >>> actually need the dma_addr_t, not the phys_addr_t, so I'll have to >>> convert. In every case, this is a conversion I've already done and that I >>> need in the calling code as well. >> >> Does >> >> dma_addr_t dma_map_range(struct device *hwdev, phys_addr_t addr, >> size_t size); >> >> work for you? >> >> If the range does not need mapping then it returns the dma address, if >> you needed to calculate the dma address anyway to figure out if mapping >> is required then this is fine. If the range does need mapping then it >> returns NULL. >> > > My only concern is whether dma_addr_t == 0 is actually equivalent to NULL. > That is, can we be sure that address 0 will never be used? > Indeed, I remember seeing 0 returned on pci_alloc_coherent() as an address (cookie).
Regards, -- Leon -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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