Replacing dma_alloc_writecombine for aarch64
Catalin Marinas
catalin.marinas at arm.com
Mon Dec 3 12:25:25 EST 2012
On Mon, Dec 03, 2012 at 05:18:35PM +0000, Ryan Harkin wrote:
> Some time ago, I converted the PL111 driver to use device tree [1]. I
> gathered some feedback after an RFC and I was recently updating my
> driver. However, with my aarch64 work, I found that the driver
> doesn't compile for aarch64 because I've been using
> dma_alloc_writecombine in the driver. As aarch64 doesn't use the
> driver with DMA, I hacked it to get my aarch64 branch working.
>
> Is there another API you can recommend I use for DMA that will work
> with both flavours?
You can use dma_alloc_coherent() which gives the same thing on ARMv7
(and some ARMv6) and AArch64 (write-combine memory). However, there is
ARMv5 where this translates to strongly ordered memory, so you can't the
coherent variant all the time.
--
Catalin
More information about the linux-arm-kernel
mailing list