diff options
Diffstat (limited to 'drivers/iommu/Kconfig')
| -rw-r--r-- | drivers/iommu/Kconfig | 71 |
1 files changed, 64 insertions, 7 deletions
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index 07b7c25cbed8..8ad8618b3530 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -79,16 +79,57 @@ config IOMMU_DEBUGFS debug/iommu directory, and then populate a subdirectory with entries as required. -config IOMMU_DEFAULT_PASSTHROUGH - bool "IOMMU passthrough by default" +choice + prompt "IOMMU default domain type" depends on IOMMU_API + default IOMMU_DEFAULT_DMA_LAZY if AMD_IOMMU || INTEL_IOMMU + default IOMMU_DEFAULT_DMA_STRICT help - Enable passthrough by default, removing the need to pass in - iommu.passthrough=on or iommu=pt through command line. If this - is enabled, you can still disable with iommu.passthrough=off - or iommu=nopt depending on the architecture. + Choose the type of IOMMU domain used to manage DMA API usage by + device drivers. The options here typically represent different + levels of tradeoff between robustness/security and performance, + depending on the IOMMU driver. Not all IOMMUs support all options. + This choice can be overridden at boot via the command line, and for + some devices also at runtime via sysfs. - If unsure, say N here. + If unsure, keep the default. + +config IOMMU_DEFAULT_DMA_STRICT + bool "Translated - Strict" + help + Trusted devices use translation to restrict their access to only + DMA-mapped pages, with strict TLB invalidation on unmap. Equivalent + to passing "iommu.passthrough=0 iommu.strict=1" on the command line. + + Untrusted devices always use this mode, with an additional layer of + bounce-buffering such that they cannot gain access to any unrelated + data within a mapped page. + +config IOMMU_DEFAULT_DMA_LAZY + bool "Translated - Lazy" + help + Trusted devices use translation to restrict their access to only + DMA-mapped pages, but with "lazy" batched TLB invalidation. This + mode allows higher performance with some IOMMUs due to reduced TLB + flushing, but at the cost of reduced isolation since devices may be + able to access memory for some time after it has been unmapped. + Equivalent to passing "iommu.passthrough=0 iommu.strict=0" on the + command line. + + If this mode is not supported by the IOMMU driver, the effective + runtime default will fall back to IOMMU_DEFAULT_DMA_STRICT. + +config IOMMU_DEFAULT_PASSTHROUGH + bool "Passthrough" + help + Trusted devices are identity-mapped, giving them unrestricted access + to memory with minimal performance overhead. Equivalent to passing + "iommu.passthrough=1" (historically "iommu=pt") on the command line. + + If this mode is not supported by the IOMMU driver, the effective + runtime default will fall back to IOMMU_DEFAULT_DMA_STRICT. + +endchoice config OF_IOMMU def_bool y @@ -249,10 +290,25 @@ config SPAPR_TCE_IOMMU Enables bits of IOMMU API required by VFIO. The iommu_ops is not implemented as it is not necessary for VFIO. +config APPLE_DART + tristate "Apple DART IOMMU Support" + depends on ARCH_APPLE || (COMPILE_TEST && !GENERIC_ATOMIC64) + select IOMMU_API + select IOMMU_IO_PGTABLE_LPAE + default ARCH_APPLE + help + Support for Apple DART (Device Address Resolution Table) IOMMUs + found in Apple ARM SoCs like the M1. + This IOMMU is required for most peripherals using DMA to access + the main memory. + + Say Y here if you are using an Apple SoC. + # ARM IOMMU support config ARM_SMMU tristate "ARM Ltd. System MMU (SMMU) Support" depends on ARM64 || ARM || (COMPILE_TEST && !GENERIC_ATOMIC64) + depends on QCOM_SCM || !QCOM_SCM #if QCOM_SCM=m this can't be =y select IOMMU_API select IOMMU_IO_PGTABLE_LPAE select ARM_DMA_USE_IOMMU if ARM @@ -382,6 +438,7 @@ config QCOM_IOMMU # Note: iommu drivers cannot (yet?) be built as modules bool "Qualcomm IOMMU Support" depends on ARCH_QCOM || (COMPILE_TEST && !GENERIC_ATOMIC64) + depends on QCOM_SCM=y select IOMMU_API select IOMMU_IO_PGTABLE_LPAE select ARM_DMA_USE_IOMMU |