APPLIED[artful]: [Resend][pull request][SRU][Zesty] Support SMMU passthrough using the default domain

[Seth Forshee]

On Fri, May 19, 2017 at 09:40:54PM -0500, Manoj Iyer wrote:
> Paolo found build issues with the patch series I had sent earlier and nak'ed
> it because of build failure. Rather than sending large number of patches
> with git send-email I am resending these as a pull-request (I should have
> done this initially).
> 
> I am resending the patch series to add  support for SMMU passthrough using
> the default domain, the patch series implements a kernel command-line option
> iommu.passthrough=0/1 1 - Bypass the IOMMU for DMA, 0 - Use IOMMU
> translation for DMA. This feature  is desired on both Qualcomm Centriq 2400
> and Thunder-X platforms.
> 
> The bug report http://bugs.launchpad.net/bugs/1688158 has detailed test
> results from Qualcomm demonstrating performance improvements using
> passthrough. I  have  also tested the kernel on Thundex-X for any
> regressions, for both boot test and  pci passthrough.
> 
> I builtsuccessfully the kernel in the centriq ppa with patches applied to
> zesty master for ARM64, AMD64 and i386.
> https://launchpad.net/~centriq-team/+archive/ubuntu/sru/+packages
> 
> Please consider this patch series for review and SRU to zesty.
> 
> The following changes since commit 6e2b676684d740b6c781cf631453127f3f4d7631:
> 
>  UBUNTU: Ubuntu-4.10.0-21.23 (2017-04-28 12:46:22 +0200)
> 
> are available in the git repository at:
> 
>  git+ssh://git.launchpad.net/~centriq-team/+git/linux-sru lp1688158
> 
> for you to fetch changes up to ac9d3fd2c6f4a7d7bd0d3329ac073eca1961f8e5:
> 
>  arm64: dma-mapping: Only swizzle DMA ops for IOMMU_DOMAIN_DMA (2017-05-19
> 14:40:57 -0500)

Applied the following patches from 4.12 to artful/master-next:

iommu/arm-smmu: Restrict domain attributes to UNMANAGED domains
iommu/arm-smmu: Install bypass S2CRs for IOMMU_DOMAIN_IDENTITY domains
iommu/arm-smmu-v3: Make arm_smmu_install_ste_for_dev return void
iommu/arm-smmu-v3: Install bypass STEs for IOMMU_DOMAIN_IDENTITY domains
iommu: Allow default domain type to be set on the kernel command line