lkml.org 
[lkml]   [2019]   [Oct]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v2] dt-bindings: iommu: Convert Arm SMMUv3 to DT schema
From
Date
On 14/10/2019 20:12, Rob Herring wrote:
> Convert the Arm SMMv3 binding to the DT schema format.
>
> Cc: Joerg Roedel <joro@8bytes.org>
> Cc: Mark Rutland <mark.rutland@arm.com>
> Cc: Will Deacon <will@kernel.org>
> Cc: Robin Murphy <Robin.Murphy@arm.com>
> Cc: iommu@lists.linux-foundation.org
> Signed-off-by: Rob Herring <robh@kernel.org>
> ---
> v2:
> - Refine interrupt definition based on Robin's comments
>
> .../devicetree/bindings/iommu/arm,smmu-v3.txt | 77 --------------
> .../bindings/iommu/arm,smmu-v3.yaml | 100 ++++++++++++++++++
> 2 files changed, 100 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.txt b/Documentation/devicetree/bindings/iommu/arm,smmu-v3.txt
> deleted file mode 100644
> index c9abbf3e4f68..000000000000
> --- a/Documentation/devicetree/bindings/iommu/arm,smmu-v3.txt
> +++ /dev/null
> @@ -1,77 +0,0 @@
> -* ARM SMMUv3 Architecture Implementation
> -
> -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.
> -
> -** SMMUv3 required properties:
> -
> -- compatible : Should include:
> -
> - * "arm,smmu-v3" for any SMMUv3 compliant
> - implementation. This entry should be last in the
> - compatible list.
> -
> -- reg : Base address and size of the SMMU.
> -
> -- interrupts : Non-secure interrupt list describing the wired
> - interrupt sources corresponding to entries in
> - interrupt-names. If no wired interrupts are
> - present then this property may be omitted.
> -
> -- interrupt-names : When the interrupts property is present, should
> - include the following:
> - * "eventq" - Event Queue not empty
> - * "priq" - PRI Queue not empty
> - * "cmdq-sync" - CMD_SYNC complete
> - * "gerror" - Global Error activated
> - * "combined" - 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.
> -
> -- #iommu-cells : See the generic IOMMU binding described in
> - devicetree/bindings/pci/pci-iommu.txt
> - for details. For SMMUv3, must be 1, with each cell
> - describing a single stream ID. All possible stream
> - IDs which a device may emit must be described.
> -
> -** SMMUv3 optional properties:
> -
> -- dma-coherent : Present if DMA operations made by the SMMU (page
> - table walks, stream table accesses etc) are cache
> - coherent with the CPU.
> -
> - NOTE: this only applies to the SMMU itself, not
> - masters connected upstream of the SMMU.
> -
> -- msi-parent : See the generic MSI binding described in
> - devicetree/bindings/interrupt-controller/msi.txt
> - for a description of the msi-parent property.
> -
> -- hisilicon,broken-prefetch-cmd
> - : Avoid sending CMD_PREFETCH_* commands to the SMMU.
> -
> -- cavium,cn9900-broken-page1-regspace
> - : 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.
> -
> -** Example
> -
> - smmu@2b400000 {
> - compatible = "arm,smmu-v3";
> - reg = <0x0 0x2b400000 0x0 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", "priq", "cmdq-sync", "gerror";
> - dma-coherent;
> - #iommu-cells = <1>;
> - msi-parent = <&its 0xff0000>;
> - };
> 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..662cbc4592c9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iommu/arm,smmu-v3.yaml
> @@ -0,0 +1,100 @@
> +# 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.
> + - items:
> + - const: eventq # Event Queue not empt
> + - const: priq # PRI Queue not empty
> + - const: cmdq-sync # CMD_SYNC complete
> + - const: gerror # Global Error activated

Isn't this effectively redundant with the 4-item case of the version
below? If it's purely about the ordering, and we can't express "one or
more of any of:" without spelling out all 64 possible permutations, then
TBH I'd rather just settle on a single definition that can work for all
current cases and update the Fast Model DT if necessary.

Otherwise, though, this looks like a fair starting point to me;

Reviewed-by: Robin Murphy <robin.murphy@arm.com>

> + - minItems: 2
> + maxItems: 4
> + items:
> + - const: eventq
> + - const: gerror
> + - const: priq
> + - const: cmdq-sync
> +
> + '#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", "priq", "cmdq-sync", "gerror";
> + dma-coherent;
> + #iommu-cells = <1>;
> + msi-parent = <&its 0xff0000>;
> + };
>

\
 
 \ /
  Last update: 2019-10-22 18:56    [W:0.240 / U:0.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site