[PATCH 2/3] dt-bindings: iommu: add DART iommu bindings

Sven Peter
2021-03-20T15:21:30Z

DART (Device Address Resolution Table) is the iommu found on Apple
ARM SoCs such as the M1.

Signed-off-by: Sven Peter <sven@svenpeter.dev>
---
.../bindings/iommu/apple,t8103-dart.yaml | 82 +++++++++++++++++++
MAINTAINERS | 6 ++
2 files changed, 88 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iommu/apple,t8103-dart.yaml

diff --git a/Documentation/devicetree/bindings/iommu/apple,t8103-dart.yaml b/Documentation/devicetree/bindings/iommu/apple,t8103-dart.yaml
new file mode 100644
index 000000000000..2ec2d905a2ea
--- /dev/null
+++ b/Documentation/devicetree/bindings/iommu/apple,t8103-dart.yaml
@@ -0,0 +1,82 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iommu/apple,t8103-dart.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Apple DART IOMMU Implementation
+
+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 external to the CPU.
+
+ Each DART instance is capable of handling up to 16 masters
+ mapped to up tp 16 different virtual address spaces with
+ page-level read/write access control flags.
+
+ This DART IOMMU also raises interrupts in response to various
+ fault conditions.
+
+properties:
+ compatible:
+ const: apple,t8103-dart
+
+ reg:
+ const: 1
+
+ interrupts:
+ const: 1
+
+ clocks:
+ maxItems: 1
+
+ '#iommu-cells':
+ const: 1
+ description:
+ The number of the master connected to this DART.
+
+required:
+ - compatible
+ - reg
+ - '#iommu-cells'
+ - interrupts
+
+additionalProperties: false
+
+examples:
+ - |+
+ dart1: dart1@382f80000 {
+ compatible = "apple,t8103-dart";
+ reg = <0x3 0x82f80000 0x0 0x4000>;
+ interrupt-parent = <&aic>;
+ interrupts = <AIC_IRQ 781 IRQ_TYPE_LEVEL_HIGH>;
+ #iommu-cells = <1>;
+ };
+
+ master1 {
+ iommus = <&dart1 0>;
+ };
+
+ - |+
+ usb_dart0: usb_dart0@382f80000 {
+ compatible = "apple,t8103-dart";
+ reg = <0x3 0x82f80000 0x0 0x4000>;
+ interrupt-parent = <&aic>;
+ interrupts = <AIC_IRQ 781 IRQ_TYPE_LEVEL_HIGH>;
+ #iommu-cells = <1>;
+ };
+
+ usbdrd_dwc3_0: dwc3@382280000 {
+ compatible = "snps,dwc3";
+ reg = <0x3 0x82280000 0x0 0x100000>;
+ interrupt-parent = <&aic>;
+ interrupts = <AIC_IRQ 777 IRQ_TYPE_LEVEL_HIGH>;
+ iommus = <&usb_dart0 1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ dr_mode = "peripheral";
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index d5e4d93a536a..1f9a4f2de88b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1236,6 +1236,12 @@ L: linux-input@vger.kernel.org
S: Odd fixes
F: drivers/input/mouse/bcm5974.c

+APPLE DART IOMMU DRIVER
+M: Sven Peter <sven@svenpeter.dev>
+L: iommu@lists.linux-foundation.org
+S: Maintained
+F: Documentation/devicetree/bindings/iommu/apple,t8103-dart.yaml
+
APPLE SMC DRIVER
M: Henrik Rydberg <rydberg@bitmath.org>
L: linux-hwmon@vger.kernel.org
--
2.25.1