On 2024-02-01 9:05 pm, Georgi Djakov wrote:
Add common bindings for the TBUs to describe their properties. The TBUs are modelled as child devices of the IOMMU and each of them is described with their compatible, reg and stream-id-range properties. There could be other implementation specific properties to describe any resources like clocks, regulators, power-domains, interconnects that would be needed for TBU operation. Such properties will be documented in a separate vendor-specific TBU schema. Signed-off-by: Georgi Djakov <quic_c_gdjako@xxxxxxxxxxx> --- .../devicetree/bindings/iommu/arm,smmu.yaml | 14 ++++++++++ .../devicetree/bindings/iommu/tbu-common.yaml | 28 +++++++++++++++++++ 2 files changed, 42 insertions(+) create mode 100644 Documentation/devicetree/bindings/iommu/tbu-common.yaml diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml index a4042ae24770..ba3237023b39 100644 --- a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml +++ b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml @@ -235,6 +235,20 @@ properties: enabled for any given device. $ref: /schemas/types.yaml#/definitions/phandle+ '#address-cells':+ enum: [ 1, 2 ] + + '#size-cells': + enum: [ 1, 2 ] + + ranges: true + +patternProperties: + "^tbu@[0-9a-f]+$": + description: TBU child nodes + type: object + $ref: tbu-common.yaml# + required: - compatible - reg diff --git a/Documentation/devicetree/bindings/iommu/tbu-common.yaml b/Documentation/devicetree/bindings/iommu/tbu-common.yaml new file mode 100644 index 000000000000..3e95b356e572 --- /dev/null +++ b/Documentation/devicetree/bindings/iommu/tbu-common.yaml @@ -0,0 +1,28 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iommu/tbu-common.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Translation Buffer Unit (TBU) common properties + +maintainers: + - Georgi Djakov <quic_c_gdjako@xxxxxxxxxxx> + +description: + The SMMU implements a TBU for system masters. It consists if a + Translation Lookaside Buffer (TLB) that caches page tables. + +properties: + reg: + maxItems: 1 + + stream-id-range: + $ref: /schemas/types.yaml#/definitions/uint32-array + description: Stream ID range (address and size) that is assigned by the TBU + items: + minItems: 2 + maxItems: 2
Actually, even this doesn't work - for the 15-bit StreamID config, there's no guarantee that the devices behind each TBU will use a single contiguous StreamID range. Conversely, for any other config the StreamIDs are already uniquely associated with a TBU by their top 5 bits, so the "size" doesn't matter.
Thanks, Robin.
+ +additionalProperties: true +...
