Hi all, this series adds support for Host1x 'context isolation'. Since when programming engines through Host1x, userspace can program in any addresses it wants, we need some way to isolate the engines' memory spaces. Traditionally this has either been done imperfectly with a single shared IOMMU domain, or by copying and verifying the programming command stream at submit time (Host1x firewall). Since Tegra186 there is a privileged (only usable by kernel) Host1x opcode that allows setting the stream ID sent by the engine to the SMMU. So, by allocating a number of context banks and stream IDs for this purpose, and using this opcode at the beginning of each job, we can implement isolation. Due to the limited number of context banks only each process gets its own context, and not each channel. This feature also allows sharing engines among multiple VMs when used with Host1x's hardware virtualization support - up to 8 VMs can be configured with a subset of allowed stream IDs, enforced at hardware level. To implement this, this series adds a new host1x context bus, which will contain the 'struct device's corresponding to each context bank / stream ID, changes to device tree and SMMU code to allow registering the devices and using the bus, as well as the Host1x stream ID programming code and support in TegraDRM. The series is based on v5 of the "Host1x/TegraDRM UAPI" series, which still hasn't quite settled. Also, I haven't updated the device tree bindings (or converted them to YAML) yet, so this is RFC for now. Thanks! Mikko Mikko Perttunen (8): of/device: Allow specifying a custom iommu_spec to of_dma_configure gpu: host1x: Add context bus gpu: host1x: Add context device management code gpu: host1x: Program context stream ID on submission iommu/arm-smmu: Attach to host1x context device bus arm64: tegra: Add Host1x context stream IDs on Tegra186+ drm/tegra: Support context isolation drm/tegra: vic: Implement get_streamid_offset arch/arm64/boot/dts/nvidia/tegra186.dtsi | 9 ++ drivers/gpu/Makefile | 3 +- drivers/gpu/drm/tegra/drm.h | 1 + drivers/gpu/drm/tegra/uapi.h | 1 + drivers/gpu/drm/tegra/uapi/submit.c | 13 ++ drivers/gpu/drm/tegra/uapi/uapi.c | 34 ++++- drivers/gpu/drm/tegra/vic.c | 38 +++++ drivers/gpu/host1x/Kconfig | 5 + drivers/gpu/host1x/Makefile | 2 + drivers/gpu/host1x/context.c | 161 ++++++++++++++++++++++ drivers/gpu/host1x/context.h | 27 ++++ drivers/gpu/host1x/context_bus.c | 31 +++++ drivers/gpu/host1x/dev.c | 12 +- drivers/gpu/host1x/dev.h | 2 + drivers/gpu/host1x/hw/channel_hw.c | 52 ++++++- drivers/gpu/host1x/hw/host1x06_hardware.h | 10 ++ drivers/gpu/host1x/hw/host1x07_hardware.h | 10 ++ drivers/iommu/arm/arm-smmu/arm-smmu.c | 13 ++ drivers/iommu/of_iommu.c | 12 +- drivers/of/device.c | 9 +- include/linux/host1x.h | 21 +++ include/linux/host1x_context_bus.h | 15 ++ include/linux/of_device.h | 34 ++++- include/linux/of_iommu.h | 6 +- 24 files changed, 495 insertions(+), 26 deletions(-) create mode 100644 drivers/gpu/host1x/context.c create mode 100644 drivers/gpu/host1x/context.h create mode 100644 drivers/gpu/host1x/context_bus.c create mode 100644 include/linux/host1x_context_bus.h -- 2.30.0
