| Message ID | cover.1725901439.git.jan.kiszka@siemens.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | soc: ti: Add and use PVU on K3-AM65 for DMA isolation | expand |
On Mon, Sep 09, 2024 at 07:03:53PM +0200, Jan Kiszka wrote: > Changes in v6: > - make restricted DMA memory-region available to all pci-keystone > devices, moving property to unconditional section (patch 2) > > Changes in v5: > - resolve review comments on pci-host bindings > - reduce DMA memory regions to 1 - swiotlb does not support more > - move activation into overlay (controlled via firmware) > - use ks_init_vmap helper instead of loop in > rework ks_init_restricted_dma > - add more comments to pci-keystone > - use 2 chained TLBs of PVU to support maximum of swiotlb (320 MB) > > Changes in v4: > - reorder patch queue, moving all DTS changes to the back > - limit activation to IOT2050 Advanced variants > - move DMA pool to allow firmware-based expansion it up to 512M > > Changes in v3: > - fix ti,am654-pvu.yaml according to review comments > - address review comments on ti,am65-pci-host.yaml > - differentiate between different compatibles in ti,am65-pci-host.yaml > - move pvu nodes to k3-am65-main.dtsi > - reorder patch series, pulling bindings and generic DT bits to the front > > Changes in v2: > - fix dt_bindings_check issues (patch 1) > - address first review comments (patch 2) > - extend ti,am65-pci-host bindings for PVU (new patch 3) > > Only few of the K3 SoCs have an IOMMU and, thus, can isolate the system > against DMA-based attacks of external PCI devices. The AM65 is without > an IOMMU, but it comes with something close to it: the Peripheral > Virtualization Unit (PVU). > > The PVU was originally designed to establish static compartments via a > hypervisor, isolate those DMA-wise against each other and the host and > even allow remapping of guest-physical addresses. But it only provides > a static translation region, not page-granular mappings. Thus, it cannot > be handled transparently like an IOMMU. > > Now, to use the PVU for the purpose of isolated PCI devices from the > Linux host, this series takes a different approach. It defines a > restricted-dma-pool for the PCI host, using swiotlb to map all DMA > buffers from a static memory carve-out. And to enforce that the devices > actually follow this, a special PVU soc driver is introduced. The driver > permits access to the GIC ITS and otherwise waits for other drivers that > detect devices with constrained DMA to register pools with the PVU. > > For the AM65, the first (and possibly only) driver where this is > introduced is the pci-keystone host controller. Finally, this series > provides a DT overlay for the IOT2050 Advanced devices (all have > MiniPCIe or M.2 extension slots) to make use of this protection scheme. > Application of this overlay will be handled by firmware. > > Due to the cross-cutting nature of these changes, multiple subsystems > are affected. However, I wanted to present the whole thing in one series > to allow everyone to review with the complete picture in hands. If > preferred, I can also split the series up, of course. I'm not sure where this ended up. The pci-keystone.c patch looks OK to me, and I don't see any comments from the PCI folks who normally take care of host controller drivers. I guess it depends on the soc PVU driver, so I'll ack the keystone part and whoever takes the soc part can include it. > CC: Bjorn Helgaas <bhelgaas@google.com> > CC: "Krzysztof Wilczyński" <kw@linux.com> > CC: linux-pci@vger.kernel.org > CC: Lorenzo Pieralisi <lpieralisi@kernel.org> > > Jan Kiszka (7): > dt-bindings: soc: ti: Add AM65 peripheral virtualization unit > dt-bindings: PCI: ti,am65: Extend for use with PVU > soc: ti: Add IOMMU-like PVU driver > PCI: keystone: Add support for PVU-based DMA isolation on AM654 > arm64: dts: ti: k3-am65-main: Add PVU nodes > arm64: dts: ti: k3-am65-main: Add VMAP registers to PCI root complexes > arm64: dts: ti: iot2050: Add overlay for DMA isolation for devices > behind PCI RC > > .../bindings/pci/ti,am65-pci-host.yaml | 28 +- > .../bindings/soc/ti/ti,am654-pvu.yaml | 51 ++ > arch/arm64/boot/dts/ti/Makefile | 5 + > arch/arm64/boot/dts/ti/k3-am65-main.dtsi | 38 +- > ...am6548-iot2050-advanced-dma-isolation.dtso | 33 ++ > drivers/pci/controller/dwc/pci-keystone.c | 108 ++++ > drivers/soc/ti/Kconfig | 4 + > drivers/soc/ti/Makefile | 1 + > drivers/soc/ti/ti-pvu.c | 500 ++++++++++++++++++ > include/linux/ti-pvu.h | 16 + > 10 files changed, 777 insertions(+), 7 deletions(-) > create mode 100644 Documentation/devicetree/bindings/soc/ti/ti,am654-pvu.yaml > create mode 100644 arch/arm64/boot/dts/ti/k3-am6548-iot2050-advanced-dma-isolation.dtso > create mode 100644 drivers/soc/ti/ti-pvu.c > create mode 100644 include/linux/ti-pvu.h > > -- > 2.43.0 >
Changes in v6: - make restricted DMA memory-region available to all pci-keystone devices, moving property to unconditional section (patch 2) Changes in v5: - resolve review comments on pci-host bindings - reduce DMA memory regions to 1 - swiotlb does not support more - move activation into overlay (controlled via firmware) - use ks_init_vmap helper instead of loop in rework ks_init_restricted_dma - add more comments to pci-keystone - use 2 chained TLBs of PVU to support maximum of swiotlb (320 MB) Changes in v4: - reorder patch queue, moving all DTS changes to the back - limit activation to IOT2050 Advanced variants - move DMA pool to allow firmware-based expansion it up to 512M Changes in v3: - fix ti,am654-pvu.yaml according to review comments - address review comments on ti,am65-pci-host.yaml - differentiate between different compatibles in ti,am65-pci-host.yaml - move pvu nodes to k3-am65-main.dtsi - reorder patch series, pulling bindings and generic DT bits to the front Changes in v2: - fix dt_bindings_check issues (patch 1) - address first review comments (patch 2) - extend ti,am65-pci-host bindings for PVU (new patch 3) Only few of the K3 SoCs have an IOMMU and, thus, can isolate the system against DMA-based attacks of external PCI devices. The AM65 is without an IOMMU, but it comes with something close to it: the Peripheral Virtualization Unit (PVU). The PVU was originally designed to establish static compartments via a hypervisor, isolate those DMA-wise against each other and the host and even allow remapping of guest-physical addresses. But it only provides a static translation region, not page-granular mappings. Thus, it cannot be handled transparently like an IOMMU. Now, to use the PVU for the purpose of isolated PCI devices from the Linux host, this series takes a different approach. It defines a restricted-dma-pool for the PCI host, using swiotlb to map all DMA buffers from a static memory carve-out. And to enforce that the devices actually follow this, a special PVU soc driver is introduced. The driver permits access to the GIC ITS and otherwise waits for other drivers that detect devices with constrained DMA to register pools with the PVU. For the AM65, the first (and possibly only) driver where this is introduced is the pci-keystone host controller. Finally, this series provides a DT overlay for the IOT2050 Advanced devices (all have MiniPCIe or M.2 extension slots) to make use of this protection scheme. Application of this overlay will be handled by firmware. Due to the cross-cutting nature of these changes, multiple subsystems are affected. However, I wanted to present the whole thing in one series to allow everyone to review with the complete picture in hands. If preferred, I can also split the series up, of course. Jan CC: Bjorn Helgaas <bhelgaas@google.com> CC: "Krzysztof Wilczyński" <kw@linux.com> CC: linux-pci@vger.kernel.org CC: Lorenzo Pieralisi <lpieralisi@kernel.org> Jan Kiszka (7): dt-bindings: soc: ti: Add AM65 peripheral virtualization unit dt-bindings: PCI: ti,am65: Extend for use with PVU soc: ti: Add IOMMU-like PVU driver PCI: keystone: Add support for PVU-based DMA isolation on AM654 arm64: dts: ti: k3-am65-main: Add PVU nodes arm64: dts: ti: k3-am65-main: Add VMAP registers to PCI root complexes arm64: dts: ti: iot2050: Add overlay for DMA isolation for devices behind PCI RC .../bindings/pci/ti,am65-pci-host.yaml | 28 +- .../bindings/soc/ti/ti,am654-pvu.yaml | 51 ++ arch/arm64/boot/dts/ti/Makefile | 5 + arch/arm64/boot/dts/ti/k3-am65-main.dtsi | 38 +- ...am6548-iot2050-advanced-dma-isolation.dtso | 33 ++ drivers/pci/controller/dwc/pci-keystone.c | 108 ++++ drivers/soc/ti/Kconfig | 4 + drivers/soc/ti/Makefile | 1 + drivers/soc/ti/ti-pvu.c | 500 ++++++++++++++++++ include/linux/ti-pvu.h | 16 + 10 files changed, 777 insertions(+), 7 deletions(-) create mode 100644 Documentation/devicetree/bindings/soc/ti/ti,am654-pvu.yaml create mode 100644 arch/arm64/boot/dts/ti/k3-am6548-iot2050-advanced-dma-isolation.dtso create mode 100644 drivers/soc/ti/ti-pvu.c create mode 100644 include/linux/ti-pvu.h