Re: [PATCH edk2-platforms] Silicon/SynQuacer: enable coherent DMA for NETSEC and eMMC

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

On 28 November 2017 at 13:49, Leif Lindholm <leif.lindholm@linaro.org> wrote:
> On Tue, Nov 28, 2017 at 01:37:20PM +0000, Ard Biesheuvel wrote:
>> On 28 November 2017 at 13:28, Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote:
>> > As it turns out, it is surprisingly easy to configure both the NETSEC
>> > and eMMC devices as cache coherent for DMA, given that they are both
>> > behind the same SMMU which is already configured in passthrough mode.
>
> Configures in passthrough mode by edk2 or earlier firmware?
>

No, it is the CM3 firmware that configures the various SMMUs on this platform.

>> > So update the static SMMU configuration to make memory accesses performed
>> > by these devices inner shareable, inner/outer writeback cacheable, which
>> > makes them cache coherent with the CPUs.
>> >
>> > Contributed-under: TianoCore Contribution Agreement 1.1
>> > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>> > ---
>> >  Platform/Socionext/SynQuacerEvalBoard/SynQuacerEvalBoard.dsc                              |  2 +-
>> >  Silicon/Socionext/SynQuacer/DeviceTree/SynQuacer.dtsi                                     |  2 ++
>> >  Silicon/Socionext/SynQuacer/Drivers/PlatformDxe/Emmc.c                                    |  2 +-
>> >  Silicon/Socionext/SynQuacer/Drivers/PlatformDxe/PlatformDxe.c                             | 23 ++++++++++++++++++++
>> >  Silicon/Socionext/SynQuacer/Include/Platform/MemoryMap.h                                  |  4 ++++
>> >  Silicon/Socionext/SynQuacer/Library/SynQuacerMemoryInitPeiLib/SynQuacerMemoryInitPeiLib.c |  3 +++
>> >  6 files changed, 34 insertions(+), 2 deletions(-)
>> >
>> > diff --git a/Platform/Socionext/SynQuacerEvalBoard/SynQuacerEvalBoard.dsc b/Platform/Socionext/SynQuacerEvalBoard/SynQuacerEvalBoard.dsc
>> > index 7245240012bc..dd4a7f9baf69 100644
>> > --- a/Platform/Socionext/SynQuacerEvalBoard/SynQuacerEvalBoard.dsc
>> > +++ b/Platform/Socionext/SynQuacerEvalBoard/SynQuacerEvalBoard.dsc
>> > @@ -597,7 +597,7 @@ [Components.common]
>> >    NetworkPkg/HttpBootDxe/HttpBootDxe.inf
>> >    Silicon/Socionext/SynQuacer/Drivers/Net/NetsecDxe/NetsecDxe.inf {
>> >      <LibraryClasses>
>> > -      DmaLib|EmbeddedPkg/Library/NonCoherentDmaLib/NonCoherentDmaLib.inf
>> > +      DmaLib|EmbeddedPkg/Library/CoherentDmaLib/CoherentDmaLib.inf
>> >    }
>> >
>> >    #
>>
>> Note: this hunk ^^^ needs to be applied to DeveloperBox.dsc as well.
>
> Do I wait for a v2 including that?
>

Would you like me to?

I added this for Daniel and/or Masami, in case they were intending to
test this patch. I'd like to get confirmation from them or others that
this works as expected before merging this, so there is no rush.

-- 
Ard.