Re: [Devel] [PATCH v9 0/3] Cavium ThunderX2 SMMUv3 errata workarounds

[Robert Richter]

On 22.06.17 19:58:22, Will Deacon wrote:
> On Thu, Jun 22, 2017 at 07:22:57PM +0100, Will Deacon wrote:
> > On Thu, Jun 22, 2017 at 05:35:35PM +0530, Geetha sowjanya wrote:
> > > Cavium ThunderX2 SMMUv3 implementation has two Silicon Erratas.
> > > 1. Errata ID #74
> > >    SMMU register alias Page 1 is not implemented
> > > 2. Errata ID #126
> > >    SMMU doesnt support unique IRQ lines and also MSI for gerror,
> > >    eventq and cmdq-sync
> > > 
> > > The following patchset does software workaround for these two erratas.
> > 
> > I've picked up the first two patches, and left comments on the final patch.
> 
> ... except that it doesn't build:
> 
> 
> drivers/acpi/arm64/iort.c: In function âarm_smmu_v3_resource_sizeâ:
> drivers/acpi/arm64/iort.c:837:21: error: âACPI_IORT_SMMU_V3_CAVIUM_CN99XXâ undeclared (first use in this function)
>   if (smmu->model == ACPI_IORT_SMMU_V3_CAVIUM_CN99XX)
>                      ^
> drivers/acpi/arm64/iort.c:837:21: note: each undeclared identifier is reported only once for each function it appears in
> make[4]: *** [drivers/acpi/arm64/iort.o] Error 1
> 
> 
> I don't see ACPI_IORT_SMMU_V3_CAVIUM_CN99XX defined, even in linux-next.
> 
> What's the plan here?

It is defined already in acpica and we actually waiting for the acpi
maintainers to include it:

 https://github.com/acpica/acpica/commit/d00a4eb86e64

We could add

/* Until ACPICA headers cover IORT rev. C */
#ifndef ACPI_IORT_SMMU_V3_CAVIUM_CN99XX
#define ACPI_IORT_SMMU_V3_CAVIUM_CN99XX		0x2
#endif

to both files:

 drivers/acpi/arm64/iort.c
 drivers/iommu/arm-smmu-v3.c

This is similar to what Robin did.

(I checked arm64 include files and the closest was
arch/arm64/include/asm/acpi.h, bug this seems not really suitable to
me.)

I have created a separate patch to be applied at first below. We can
revert it after acpica was updated.

-Robert