linux/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml
Jean-Philippe Brucker d2f2f1d10c dt-bindings: iommu: arm,smmu-v3: Relax order of interrupt names
The QEMU devicetree uses a different order for SMMUv3 interrupt names,
and there isn't a good reason for enforcing a specific order. Since all
interrupt lines are optional, operating systems should not expect a
fixed interrupt array layout; they should instead match each interrupt
to its name individually. Besides, as a result of commit e4783856a2
("dt-bindings: iommu: arm,smmu-v3: make PRI IRQ optional"), "cmdq-sync"
and "priq" are already permutable. Relax the interrupt-names array
entirely by allowing any permutation, incidentally making the schema
more readable.

Note that dt-validate won't allow duplicate names here so we don't need
to specify maxItems or add additional checks, it's quite neat.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220916133145.1910549-1-jean-philippe@linaro.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2022-09-26 14:05:58 +02:00

96 lines
2.6 KiB
YAML

# SPDX-License-Identifier: GPL-2.0-only
%YAML 1.2
---
$id: http://devicetree.org/schemas/iommu/arm,smmu-v3.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: ARM SMMUv3 Architecture Implementation
maintainers:
- Will Deacon <will@kernel.org>
- Robin Murphy <Robin.Murphy@arm.com>
description: |+
The SMMUv3 architecture is a significant departure from previous
revisions, replacing the MMIO register interface with in-memory command
and event queues and adding support for the ATS and PRI components of
the PCIe specification.
properties:
$nodename:
pattern: "^iommu@[0-9a-f]*"
compatible:
const: arm,smmu-v3
reg:
maxItems: 1
interrupts:
minItems: 1
maxItems: 4
interrupt-names:
oneOf:
- const: combined
description:
The combined interrupt is optional, and should only be provided if the
hardware supports just a single, combined interrupt line.
If provided, then the combined interrupt will be used in preference to
any others.
- minItems: 1
items:
enum:
- eventq # Event Queue not empty
- gerror # Global Error activated
- cmdq-sync # CMD_SYNC complete
- priq # PRI Queue not empty
'#iommu-cells':
const: 1
dma-coherent:
description: |
Present if page table walks made by the SMMU are cache coherent with the
CPU.
NOTE: this only applies to the SMMU itself, not masters connected
upstream of the SMMU.
msi-parent: true
hisilicon,broken-prefetch-cmd:
type: boolean
description: Avoid sending CMD_PREFETCH_* commands to the SMMU.
cavium,cn9900-broken-page1-regspace:
type: boolean
description:
Replaces all page 1 offsets used for EVTQ_PROD/CONS, PRIQ_PROD/CONS
register access with page 0 offsets. Set for Cavium ThunderX2 silicon that
doesn't support SMMU page1 register space.
required:
- compatible
- reg
- '#iommu-cells'
additionalProperties: false
examples:
- |+
#include <dt-bindings/interrupt-controller/arm-gic.h>
#include <dt-bindings/interrupt-controller/irq.h>
iommu@2b400000 {
compatible = "arm,smmu-v3";
reg = <0x2b400000 0x20000>;
interrupts = <GIC_SPI 74 IRQ_TYPE_EDGE_RISING>,
<GIC_SPI 75 IRQ_TYPE_EDGE_RISING>,
<GIC_SPI 77 IRQ_TYPE_EDGE_RISING>,
<GIC_SPI 79 IRQ_TYPE_EDGE_RISING>;
interrupt-names = "eventq", "gerror", "priq", "cmdq-sync";
dma-coherent;
#iommu-cells = <1>;
msi-parent = <&its 0xff0000>;
};