Subject: [PATCH 00/11] powerpv/powernv: Restore pnv_npu_try_dma_set_bypass()

From: Reza Arbab <[email-masked]>
Date: Wed, 30 Oct 2019 11:59:49 -0500

With recent kernels, TCE tables for NPU devices are no longer being
configured. That task was performed by pnv_npu_try_dma_set_bypass(), a
function that got swept away in recent overhauling of dma code.

Patches 1-4 here bring the lost function back and reintegrate it with
the updated generic iommu bypass infrastructure.

Patch 5 fixes a regression in behavior when a requested dma mask can not
be fulfilled.

Patches 6-8 are cleanup. I put these later in the set because they
aren't bisectable until after the restored code is wired back in.

Patches 9-11 refactor pnv_pci_ioda_iommu_bypass_supported(). It seems
wrong for a boolean *_supported() function to have side effects. They
reintroduce a pci controller based dma_set_mask() hook. If that's
undesirable, these last three patches can be dropped.

Reza Arbab (11):
  Revert "powerpc/powernv: Remove unused pnv_npu_try_dma_set_bypass()
    function"
  powerpc/powernv: Add pnv_ioda_pe_iommu_bypass_supported()
  powerpc/powernv/npu: Change pnv_npu_try_dma_set_bypass() argument
  powerpc/powernv/npu: Wire up pnv_npu_try_dma_set_bypass()
  powerpc/powernv: Return failure for some uses of dma_set_mask()
  powerpc/powernv: Remove intermediate variable
  powerpc/powernv/npu: Simplify pnv_npu_try_dma_set_bypass() loop
  powerpc/powernv: Replace open coded pnv_ioda_get_pe()s
  Revert "powerpc/pci: remove the dma_set_mask pci_controller ops
    methods"
  powerpc/powernv: Add pnv_phb3_iommu_bypass_supported()
  powerpc/powernv: Add pnv_pci_ioda_dma_set_mask()

 arch/powerpc/include/asm/pci-bridge.h     |   2 +
 arch/powerpc/kernel/dma-iommu.c           |  19 ++++--
 arch/powerpc/kernel/dma-mask.c            |   9 +++
 arch/powerpc/platforms/powernv/Kconfig    |   1 +
 arch/powerpc/platforms/powernv/npu-dma.c  | 106 +++++++++++++++++++++++++++---
 arch/powerpc/platforms/powernv/pci-ioda.c |  71 ++++++++++++--------
 arch/powerpc/platforms/powernv/pci.h      |  10 ++-
 7 files changed, 177 insertions(+), 41 deletions(-)

-- 
1.8.3.1