Re: [PATCH 1/2] iommu/mediatek: select ARM_DMA_USE_IOMMU

From: Arnd Bergmann
Date: Mon Feb 29 2016 - 06:31:44 EST


On Monday 29 February 2016 11:22:24 Robin Murphy wrote:
> >>> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
> >>> index b325954cf8f8..ea0998921702 100644
> >>> --- a/drivers/iommu/Kconfig
> >>> +++ b/drivers/iommu/Kconfig
> >>> @@ -341,6 +341,7 @@ config MTK_IOMMU
> >>> bool "MTK IOMMU Support"
> >>> depends on ARM || ARM64
> >>> depends on ARCH_MEDIATEK || COMPILE_TEST
> >>> + select ARM_DMA_USE_IOMMU
> >>
> >> If going down this route, I'd be inclined to add an "if ARM" there, just
> >> for clarity.
> >
> > That would run into the NEED_SG_DMA_LENGTH problem on other architectures
> > that don't already set it, right?
>
> Sorry, I'm lost - wouldn't "depends on ARM || ARM64" make other
> architectures moot? arm64 already has NEED_SG_DMA_LENGTH=y by default.
>

Nevermind, I didn't notice the dependency on the architecture.

What is keeping us from having 'depends on ARM || ARM64 || COMPILE_TEST'?

I assume it doesn't work yet, but it would be nice to get that done
at some point so we can take advantage of automated build testing like
coverity.

Arnd