[PATCH kernel] powerpc/powernv/npu: Remove dead iommu code

Gavin Shan gwshan at linux.vnet.ibm.com
Wed Feb 22 09:33:59 AEDT 2017

On Tue, Feb 21, 2017 at 01:40:20PM +1100, Alexey Kardashevskiy wrote:
>PNV_IODA_PE_DEV is only used for NPU devices (emulated PCI bridges
>representing NVLink). These are added to IOMMU groups with corresponding
>NVIDIA devices after all non-NPU PEs are setup; a special helper -
>pnv_pci_ioda_setup_iommu_api() - handles this in pnv_pci_ioda_fixup().
>The pnv_pci_ioda2_setup_dma_pe() helper sets up DMA for a PE. It is called
>for VFs (so it does not handle NPU case) and PCI bridges but only
>IODA1 and IODA2 types. An NPU bridge has its own type id (PNV_PHB_NPU)
>so pnv_pci_ioda2_setup_dma_pe() cannot be called on NPU and therefore
>(pe->flags & PNV_IODA_PE_DEV) is always "false".
>This removes not used iommu_add_device(). This should not cause any
>behavioral change.
>Signed-off-by: Alexey Kardashevskiy <aik at ozlabs.ru>

Acked-by: Gavin Shan <gwshan at linux.vnet.ibm.com>

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