On Thu, Jun 03, 2021 at 10:50:02AM +0200, Sven Peter wrote: > DART (Device Address Resolution Table) is the iommu found on Apple > ARM SoCs such as the M1. > > Signed-off-by: Sven Peter <sven@xxxxxxxxxxxxx> > --- > .../devicetree/bindings/iommu/apple,dart.yaml | 81 +++++++++++++++++++ > MAINTAINERS | 6 ++ > 2 files changed, 87 insertions(+) > create mode 100644 Documentation/devicetree/bindings/iommu/apple,dart.yaml > > diff --git a/Documentation/devicetree/bindings/iommu/apple,dart.yaml b/Documentation/devicetree/bindings/iommu/apple,dart.yaml > new file mode 100644 > index 000000000000..db21ca07d121 > --- /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@xxxxxxxxxxxxx> > + > +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>; /dart1 is a path, but 'dart1' is a label. You need '&dart1' (or '&{/iommu@82f80000}' but that doesn't really work here because the examples get prefixed with /example-n/...) With that fixed, Reviewed-by: Rob Herring <robh@xxxxxxxxxx> > + }; > + > + - |+ > + 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>; > + }; > diff --git a/MAINTAINERS b/MAINTAINERS > index 673cadd5107a..4373d63f9ccf 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -1240,6 +1240,12 @@ L: linux-input@xxxxxxxxxxxxxxx > S: Odd fixes > F: drivers/input/mouse/bcm5974.c > > +APPLE DART IOMMU DRIVER > +M: Sven Peter <sven@xxxxxxxxxxxxx> > +L: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx > +S: Maintained > +F: Documentation/devicetree/bindings/iommu/apple,dart.yaml > + > APPLE SMC DRIVER > M: Henrik Rydberg <rydberg@xxxxxxxxxxx> > L: linux-hwmon@xxxxxxxxxxxxxxx > -- > 2.25.1
