Re: [PATCH v7 14/50] powerpc/powernv: M64 support on P7IOC

Gavin Shan
2015-11-17T01:43:06Z

On Mon, Nov 16, 2015 at 07:02:18PM +1100, Alexey Kardashevskiy wrote:
>On 11/05/2015 12:12 AM, Gavin Shan wrote:
>>This enables M64 window on P7IOC, which has been enabled on PHB3.
>>Different from PHB3 where 16 M64 BARs are supported and each of
>>them can be owned by one particular PE# exclusively or divided
>>evenly to 256 segments, every P7IOC PHB has 16 M64 BARs and each
>>of them are divided to 8 segments. So every P7IOC PHB supports
>>128 M64 segments in total. P7IOC has M64DT, which helps mapping
>>one particular M64 segment# to arbitrary PE#. PHB3 doesn't have
>>M64DT, indicating that one M64 segment can only be pinned to the
>>fixed PE#. In order to have same code to support M64 on P7IOC and
>>PHB3, we just provide 128 M64 segments on every P7IOC PHB and each
>>of them is pinned to the fixed PE# by bypassing the function of
>>M64DT. In turn, we just need different phb->init_m64() for P7IOC
>>and PHB3 to support M64.
>
>I thought we decided (Ben suggested?) not to push P7IOC code now (or ever) as
>there is no user for it, has this changed?
>

Remember that the code is mixed for P7IOC/PHB3. It's not harmful to support
M64 window on P7IOC, which is much larger than M32.

>btw please put ioda1/ioda2/p7ioc/etc to the subject line to make it easier to
>see how much work is there about particular PHB type. You rename quite many
>functions and I generally want to ask you to group all renaming patches first
>but it would also make sense to keep them close to (for example)
>p7ioc-related patches so having more descriptive subject lines may help.
>Thanks.
>

As the code is mixed for P7IOC/PHB3, I'm not following the line (IODA1/IODA2/p7ioc/phb3)
in this patchset. Instead, the sequence of patchset is order related to: cod refactoring,
IO/M32/M64, DMA, PE allocation/releaseing.

Thanks,
Gavin