[PATCH] fsldma: add support to 36-bit physical address

Timur Tabi timur.tabi at gmail.com
Wed Sep 22 07:43:12 EST 2010

On Tue, Sep 21, 2010 at 4:34 PM, Scott Wood <scottwood at freescale.com> wrote:

> This doesn't control allocation (it probably should with
> dma_alloc_coherent, though I don't see it in the code), it controls
> whether swiotlb will create a bounce buffer -- defeating the point of
> using DMA to accelerate a memcpy.

But it would do that only for the 'dev' used in the dma_set_mask()
call.  That dev is only used here:

	chan->desc_pool = dma_pool_create("fsl_dma_engine_desc_pool",
					  sizeof(struct fsl_desc_sw),
					  __alignof__(struct fsl_desc_sw), 0);

Since we don't DMA the descriptors themselves, I just don't see how
this patch does anything.

Timur Tabi
Linux kernel developer at Freescale

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