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authorLinus Torvalds <torvalds@linux-foundation.org>2021-09-03 20:44:35 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2021-09-03 20:44:35 +0300
commit69a5c49a9147e9daca76201e3d6edfea5ed8403a (patch)
treea78018f48e2b278d68363bffd07716527b168325 /Documentation
parent3de18c865f504ab59ed2588b1e11acd4bcb9ea09 (diff)
parentd8768d7eb9c21ef928adb93402d9348bcc4a6915 (diff)
downloadlinux-69a5c49a9147e9daca76201e3d6edfea5ed8403a.tar.xz
Merge tag 'iommu-updates-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull iommu updates from Joerg Roedel: - New DART IOMMU driver for Apple Silicon M1 chips - Optimizations for iommu_[map/unmap] performance - Selective TLB flush support for the AMD IOMMU driver to make it more efficient on emulated IOMMUs - Rework IOVA setup and default domain type setting to move more code out of IOMMU drivers and to support runtime switching between certain types of default domains - VT-d Updates from Lu Baolu: - Update the virtual command related registers - Enable Intel IOMMU scalable mode by default - Preset A/D bits for user space DMA usage - Allow devices to have more than 32 outstanding PRs - Various cleanups - ARM SMMU Updates from Will Deacon: SMMUv3: - Minor optimisation to avoid zeroing struct members on CMD submission - Increased use of batched commands to reduce submission latency - Refactoring in preparation for ECMDQ support SMMUv2: - Fix races when probing devices with identical StreamIDs - Optimise walk cache flushing for Qualcomm implementations - Allow deep sleep states for some Qualcomm SoCs with shared clocks - Various smaller optimizations, cleanups, and fixes * tag 'iommu-updates-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (85 commits) iommu/io-pgtable: Abstract iommu_iotlb_gather access iommu/arm-smmu: Fix missing unlock on error in arm_smmu_device_group() iommu/vt-d: Add present bit check in pasid entry setup helpers iommu/vt-d: Use pasid_pte_is_present() helper function iommu/vt-d: Drop the kernel doc annotation iommu/vt-d: Allow devices to have more than 32 outstanding PRs iommu/vt-d: Preset A/D bits for user space DMA usage iommu/vt-d: Enable Intel IOMMU scalable mode by default iommu/vt-d: Refactor Kconfig a bit iommu/vt-d: Remove unnecessary oom message iommu/vt-d: Update the virtual command related registers iommu: Allow enabling non-strict mode dynamically iommu: Merge strictness and domain type configs iommu: Only log strictness for DMA domains iommu: Expose DMA domain strictness via sysfs iommu: Express DMA strictness via the domain type iommu/vt-d: Prepare for multiple DMA domain types iommu/arm-smmu: Prepare for multiple DMA domain types iommu/amd: Prepare for multiple DMA domain types iommu: Introduce explicit type for non-strict DMA domains ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/ABI/testing/sysfs-kernel-iommu_groups6
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt29
-rw-r--r--Documentation/devicetree/bindings/iommu/apple,dart.yaml81
3 files changed, 98 insertions, 18 deletions
diff --git a/Documentation/ABI/testing/sysfs-kernel-iommu_groups b/Documentation/ABI/testing/sysfs-kernel-iommu_groups
index eae2f1c1e11e..b15af6a5bc08 100644
--- a/Documentation/ABI/testing/sysfs-kernel-iommu_groups
+++ b/Documentation/ABI/testing/sysfs-kernel-iommu_groups
@@ -42,8 +42,12 @@ Description: /sys/kernel/iommu_groups/<grp_id>/type shows the type of default
======== ======================================================
DMA All the DMA transactions from the device in this group
are translated by the iommu.
+ DMA-FQ As above, but using batched invalidation to lazily
+ remove translations after use. This may offer reduced
+ overhead at the cost of reduced memory protection.
identity All the DMA transactions from the device in this group
- are not translated by the iommu.
+ are not translated by the iommu. Maximum performance
+ but zero protection.
auto Change to the type the device was booted with.
======== ======================================================
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 84dc5790741b..828d11441ebf 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -301,10 +301,7 @@
amd_iommu= [HW,X86-64]
Pass parameters to the AMD IOMMU driver in the system.
Possible values are:
- fullflush - enable flushing of IO/TLB entries when
- they are unmapped. Otherwise they are
- flushed before they will be reused, which
- is a lot of faster
+ fullflush - Deprecated, equivalent to iommu.strict=1
off - do not initialize any AMD IOMMU found in
the system
force_isolation - Force device isolation for all
@@ -1958,18 +1955,17 @@
this case, gfx device will use physical address for
DMA.
strict [Default Off]
- With this option on every unmap_single operation will
- result in a hardware IOTLB flush operation as opposed
- to batching them for performance.
+ Deprecated, equivalent to iommu.strict=1.
sp_off [Default Off]
By default, super page will be supported if Intel IOMMU
has the capability. With this option, super page will
not be supported.
- sm_on [Default Off]
- By default, scalable mode will be disabled even if the
- hardware advertises that it has support for the scalable
- mode translation. With this option set, scalable mode
- will be used on hardware which claims to support it.
+ sm_on
+ Enable the Intel IOMMU scalable mode if the hardware
+ advertises that it has support for the scalable mode
+ translation.
+ sm_off
+ Disallow use of the Intel IOMMU scalable mode.
tboot_noforce [Default Off]
Do not force the Intel IOMMU enabled under tboot.
By default, tboot will force Intel IOMMU on, which
@@ -2061,13 +2057,12 @@
throughput at the cost of reduced device isolation.
Will fall back to strict mode if not supported by
the relevant IOMMU driver.
- 1 - Strict mode (default).
+ 1 - Strict mode.
DMA unmap operations invalidate IOMMU hardware TLBs
synchronously.
- Note: on x86, the default behaviour depends on the
- equivalent driver-specific parameters, but a strict
- mode explicitly specified by either method takes
- precedence.
+ unset - Use value of CONFIG_IOMMU_DEFAULT_DMA_{LAZY,STRICT}.
+ Note: on x86, strict mode specified via one of the
+ legacy driver-specific options takes precedence.
iommu.passthrough=
[ARM64, X86] Configure DMA to bypass the IOMMU by default.
diff --git a/Documentation/devicetree/bindings/iommu/apple,dart.yaml b/Documentation/devicetree/bindings/iommu/apple,dart.yaml
new file mode 100644
index 000000000000..94aa9e9afa59
--- /dev/null
+++ b/Documentation/devicetree/bindings/iommu/apple,dart.yaml
@@ -0,0 +1,81 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iommu/apple,dart.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Apple DART IOMMU
+
+maintainers:
+ - Sven Peter <sven@svenpeter.dev>
+
+description: |+
+ Apple SoCs may contain an implementation of their Device Address
+ Resolution Table which provides a mandatory layer of address
+ translations for various masters.
+
+ Each DART instance is capable of handling up to 16 different streams
+ with individual pagetables and page-level read/write protection flags.
+
+ This DART IOMMU also raises interrupts in response to various
+ fault conditions.
+
+properties:
+ compatible:
+ const: apple,t8103-dart
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ clocks:
+ description:
+ Reference to the gate clock phandle if required for this IOMMU.
+ Optional since not all IOMMUs are attached to a clock gate.
+
+ '#iommu-cells':
+ const: 1
+ description:
+ Has to be one. The single cell describes the stream id emitted by
+ a master to the IOMMU.
+
+required:
+ - compatible
+ - reg
+ - '#iommu-cells'
+ - interrupts
+
+additionalProperties: false
+
+examples:
+ - |+
+ dart1: iommu@82f80000 {
+ compatible = "apple,t8103-dart";
+ reg = <0x82f80000 0x4000>;
+ interrupts = <1 781 4>;
+ #iommu-cells = <1>;
+ };
+
+ master1 {
+ iommus = <&dart1 0>;
+ };
+
+ - |+
+ dart2a: iommu@82f00000 {
+ compatible = "apple,t8103-dart";
+ reg = <0x82f00000 0x4000>;
+ interrupts = <1 781 4>;
+ #iommu-cells = <1>;
+ };
+ dart2b: iommu@82f80000 {
+ compatible = "apple,t8103-dart";
+ reg = <0x82f80000 0x4000>;
+ interrupts = <1 781 4>;
+ #iommu-cells = <1>;
+ };
+
+ master2 {
+ iommus = <&dart2a 0>, <&dart2b 1>;
+ };