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

On Mon, Nov 16, 2015 at 07:02:18PM +1100, Alexey Kardashevskiy wrote:

On 11/05/2015 12:12 AM, Gavin Shan wrote:

quoted

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