[PATCH v2 1/9] arm: mvebu: Limit the DMA zone when LPAE is selected

[Gregory CLEMENT]

On 04/05/2013 10:41 PM, Arnd Bergmann wrote:
> On Friday 05 April 2013, Gregory CLEMENT wrote:
>> When LPAE is activated on Armada XP, all registers and IOs are still
>> 32bit, the 40bit extension is on the CPU to DRAM path (windows) only.
>> That means that all the DMA transfer are restricted to the low 32 bits
>> address space. This is limitation is achieved by selecting ZONE_DMA.
>>
>> Signed-off-by: Gregory CLEMENT <gregory.clement at free-electrons.com>
> 
> 
> Shouldn't that be ZONE_DMA32?
> 

Well common code for ARM don't manage the ZONE_DMA32. Whereas with
ZONE_DMA, setup_dma_zone() in arch/arm/mm/init.c does exactly what
I want: setting arm_dma_limit to 0xffffffff.

ZONE_DMA32 is used on arm64 however.

> 	Arnd
> 


-- 
Gregory Clement, Free Electrons
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development, consulting, training and support.
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