[PATCH 5/5] powerpc: Add 86xx support for SWIOTLB

[Becky Bruce]

On Apr 20, 2009, at 12:00 PM, Kumar Gala wrote:

>
> On Apr 20, 2009, at 11:26 AM, Becky Bruce wrote:
>
>> Minor code to allow enabling swiotlb on mpc86xx, including
>> Kconfig addition for SWIOTLB.
>>
>> Signed-off-by: Becky Bruce <beckyb at kernel.crashing.org>
>> ---
>> arch/powerpc/Kconfig                       |   10 ++++++++++
>> arch/powerpc/kernel/dma-swiotlb.c          |    2 ++
>> arch/powerpc/platforms/86xx/mpc86xx_hpcn.c |    3 +++
>> 3 files changed, 15 insertions(+), 0 deletions(-)
>>
>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
>> index 197f6a3..e47c81d 100644
>> --- a/arch/powerpc/Kconfig
>> +++ b/arch/powerpc/Kconfig
>> @@ -292,6 +292,16 @@ config IOMMU_VMERGE
>> config IOMMU_HELPER
>> 	def_bool PPC64
>>
>> +config SWIOTLB
>> +	bool "SWIOTLB support"
>> +	depends on PPC_86xx
>> +	select IOMMU_HELPER
>> +	---help---
>> +	  Support for IO bounce buffering for systems without an IOMMU.
>> +	  This allows us to DMA to the full physical address space on
>> +	  platforms where the size of a physical address is larger
>> +	  than the bus address.
>> +
>
> As stated on previous patch, move the bulk of this into 4/5.

Yep.

>
>
>>
>> config PPC_NEED_DMA_SYNC_OPS
>> 	def_bool y
>> 	depends on (NOT_COHERENT_CACHE || SWIOTLB)
>> diff --git a/arch/powerpc/kernel/dma-swiotlb.c b/arch/powerpc/ 
>> kernel/dma-swiotlb.c
>> index 29a68e6..3065d03 100644
>> --- a/arch/powerpc/kernel/dma-swiotlb.c
>> +++ b/arch/powerpc/kernel/dma-swiotlb.c
>> @@ -159,3 +159,5 @@ static int __init setup_bus_notifier(void)
>>
>> 	return 0;
>> }
>> +
>> +machine_arch_initcall(mpc86xx_hpcn, setup_bus_notifier);
>
> Hmm, not sure what we chatted about here, but I don't want to have  
> to add every board into this file to register the bus notifiers.

We talked about this, and this was what we decided on - I don't really  
like the idea, either, but there's a lot of precedent for it.  I'd  
like to do this differently, but I"m not sure what the solution is -  
we'd need to look into that more (or perhaps someone here will have  
some sage advice).

Cheers,
B