On Fri, Sep 20, 2019 at 9:17 AM Robin Murphy <robin.murphy@xxxxxxx> wrote: > > On 20/09/2019 14:48, Rob Herring wrote: > > Convert the Arm SMMv3 binding to the DT schema format. > > > > Cc: Joerg Roedel <joro@xxxxxxxxxx> > > Cc: Mark Rutland <mark.rutland@xxxxxxx> > > Cc: Will Deacon <will@xxxxxxxxxx> > > Cc: Robin Murphy <Robin.Murphy@xxxxxxx> > > Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx > > Signed-off-by: Rob Herring <robh@xxxxxxxxxx> > > --- > > .../devicetree/bindings/iommu/arm,smmu-v3.txt | 77 ------------- > > .../bindings/iommu/arm,smmu-v3.yaml | 103 ++++++++++++++++++ > > 2 files changed, 103 insertions(+), 77 deletions(-) > > delete mode 100644 Documentation/devicetree/bindings/iommu/arm,smmu-v3.txt > > create mode 100644 Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml > > diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml b/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml > > new file mode 100644 > > index 000000000000..1c97bcfbf82b > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml > > @@ -0,0 +1,103 @@ > > +# 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@xxxxxxxxxx> > > + - Robin Murphy <Robin.Murphy@xxxxxxx> > > + > > +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. > > + - items: > > + - const: eventq # Event Queue not empty > > + - const: priq # PRI Queue not empty > > + - const: cmdq-sync # CMD_SYNC complete > > + - const: gerror # Global Error activated > > + - items: > > + - const: eventq > > + - const: gerror > > + - const: priq > > + - items: > > + - const: eventq > > + - const: gerror > > + - items: > > + - const: eventq > > + - const: priq > > This looks a bit off - in the absence of MSIs, at least "gerror" and > "eventq" should be mandatory; "cmdq-sync" should probably also be from a > binding perspective, but Linux doesn't care about it. PRI is an optional > feature of the architecture, so that IRQ should always be optional. If > we do have MSIs, then technically the implementation is allowed to not > support wired IRQs at all, although in practice is likely to have at > least "gerror" to signal the double-fault condition of a GERROR MSI > write aborting. Well, now I'm not sure where I came up with the last case, it can be dropped. These are the cases we have: arch/arm64/boot/dts/arm/fvp-base-revc.dts: interrupt-names = "eventq", "priq", "cmdq-sync", "gerror"; arch/arm64/boot/dts/hisilicon/hip07.dtsi: interrupt-names = "eventq", "gerror", "priq"; arch/arm64/boot/dts/ti/k3-j721e-main.dtsi: interrupt-names = "eventq", "gerror"; I'm fine if we leave warnings and expect dts files to be fixed. In an ideal world we'd have this with optional irq on the end: - minItems: 3 maxItems: 4 items: - const: eventq # Event Queue not empty - const: cmdq-sync # CMD_SYNC complete - const: gerror # Global Error activated - const: priq # PRI Queue not empty A less invasive approach would be: - items: - const: eventq # Event Queue not empty - const: priq # PRI Queue not empty - const: cmdq-sync # CMD_SYNC complete - const: gerror # Global Error activated - minItems: 2 maxItems: 4 items: - const: eventq - const: gerror - const: priq - const: cmdq-sync Rob
