[Linaro-acpi] [V2 PATCH 2/5] arm64 : Introduce support for ACPI _CCA object

Tom Lendacky thomas.lendacky at amd.com
Tue May 5 09:24:03 PDT 2015

On 05/05/2015 11:13 AM, Suravee Suthikulanit wrote:
> On 5/5/2015 11:12 AM, Arnd Bergmann wrote:
>> On Tuesday 05 May 2015 11:09:38 Suravee Suthikulanit wrote:
>>> However, codes in several places are making use of dma_map_ops without
>>> checking if the ops are NULL (i.e.
>>> include/asm-generic/dma-mapping-common.h and in arch-specific
>>> implementation). If setting it to NULL is what we are planning to
>>> support, we would need to scrub the current code to put NULL check.
>>> Also, would you consider if that is safe to do going forward?
>> I mean the dma_mask pointer, not dma_map_ops.

Except a lot of drivers will actually set the dma_mask pointer during
probe (usually by setting dev->dma_mask = &dev->coherent_dma_mask or by
calling dma_coerce_mask_and_coherent).  So I think the dummy_dma_ops
might be the safest way to go.


>>     Arnd
> Ah, got it. Sorry for confusion.
> Suravee
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