Anyone? Is it totally useless or wrong approach? Thanks, On 08/04/2020 19:43, Alexey Kardashevskiy wrote: > > > On 23/03/2020 18:53, Alexey Kardashevskiy wrote: >> Here is an attempt to support bigger DMA space for devices >> supporting DMA masks less than 59 bits (GPUs come into mind >> first). POWER9 PHBs have an option to map 2 windows at 0 >> and select a windows based on DMA address being below or above >> 4GB. >> >> This adds the "iommu=iommu_bypass" kernel parameter and >> supports VFIO+pseries machine - current this requires telling >> upstream+unmodified QEMU about this via >> -global spapr-pci-host-bridge.dma64_win_addr=0x100000000 >> or per-phb property. 4/4 advertises the new option but >> there is no automation around it in QEMU (should it be?). >> >> For now it is either 1<<59 or 4GB mode; dynamic switching is >> not supported (could be via sysfs). >> >> This is a rebased version of >> https://lore.kernel.org/kvm/20191202015953.127902-1-aik@xxxxxxxxx/ >> >> The main change since v1 is that now it is 7 patches with >> clearer separation of steps. >> >> >> This is based on 6c90b86a745a "Merge tag 'mmc-v5.6-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc" >> >> Please comment. Thanks. > > Ping? > > >> >> >> >> Alexey Kardashevskiy (7): >> powerpc/powernv/ioda: Move TCE bypass base to PE >> powerpc/powernv/ioda: Rework for huge DMA window at 4GB >> powerpc/powernv/ioda: Allow smaller TCE table levels >> powerpc/powernv/phb4: Use IOMMU instead of bypassing >> powerpc/iommu: Add a window number to >> iommu_table_group_ops::get_table_size >> powerpc/powernv/phb4: Add 4GB IOMMU bypass mode >> vfio/spapr_tce: Advertise and allow a huge DMA windows at 4GB >> >> arch/powerpc/include/asm/iommu.h | 3 + >> arch/powerpc/include/asm/opal-api.h | 9 +- >> arch/powerpc/include/asm/opal.h | 2 + >> arch/powerpc/platforms/powernv/pci.h | 4 +- >> include/uapi/linux/vfio.h | 2 + >> arch/powerpc/platforms/powernv/npu-dma.c | 1 + >> arch/powerpc/platforms/powernv/opal-call.c | 2 + >> arch/powerpc/platforms/powernv/pci-ioda-tce.c | 4 +- >> arch/powerpc/platforms/powernv/pci-ioda.c | 234 ++++++++++++++---- >> drivers/vfio/vfio_iommu_spapr_tce.c | 17 +- >> 10 files changed, 213 insertions(+), 65 deletions(-) >> > -- Alexey
