[PATCH v2] fsldma: add support to 36-bit physical address

Kumar Gala galak at kernel.crashing.org
Tue Nov 16 02:16:57 EST 2010


On Nov 13, 2010, at 4:43 PM, Timur Tabi wrote:

> On Thu, Nov 11, 2010 at 5:56 AM, Kumar Gala <galak at kernel.crashing.org> wrote:
> 
>> Is there any reason we shouldn't set DMA_BIT_MASK(64) since the DMA block programming model allows the address to be 64-bits?
> 
> Can you explain that?  The DMA registers only have room for 36 bits
> for the physical address.

The programming model (if you look at the free-space in the registers and data structures) supports a 64-bit address.  I'm trying to avoid changing the driver in the future if we have >36-bit.  However this is such a minor worry that I'll stop and just ack the patch as is.

- k


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