[PATCH v2] mtd: onenand: omap2: Disable DMA for HIGHMEM buffers
Boris Brezillon
boris.brezillon at bootlin.com
Fri Apr 20 13:01:34 PDT 2018
Hi Ladislav,
On Mon, 16 Apr 2018 08:52:59 +0200
Ladislav Michl <ladis at linux-mips.org> wrote:
> dma_map_single doesn't get the proper DMA address for vmalloced area,
That's not true, it returns the right DMA (physical) address, it's just
that:
1/ the memory location is not necessarily physically contiguous
2/ in case your arch is VIVT ot VIPT, there may be several entries in
the cache pointing to the same physical location, and the cache
maintenance operations done by dma_map_single() will only operate on
one of these entries.
> so disable DMA in this case.
>
The fix looks good though. Can you rephrase your commit message to make
it clearer.
Thanks,
Boris
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