Re: [PATCH v5 1/7] dt-bindings: Arm: Add Firmware Framework for Armv8-A (FF-A) binding
From: Sumit Garg <hidden>
Date: 2021-03-26 05:06:55
Also in:
linux-devicetree
Hi Sudeep, Apologies for catching up late on this patch-set. On Thu, 25 Mar 2021 at 20:05, Sudeep Holla [off-list ref] wrote:
Since the FF-A v1.0 specification doesn't list the UUID of all the partitions in the discovery API, we need to specify the UUID of the partitions that need to be accessed by drivers within the kernel.
Wouldn't we be able to implement auto-discovery of ffa partitions? I think enumeration of ffa partitions on FFA bus should be quite similar to enumeration of TAs on TEE bus (see [1]). Otherwise we need to put these redundant DT entries for every ffa partition which IMHO would bloat up device trees for every platform. [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/tee/optee/device.c#n153 -Sumit
quoted hunk ↗ jump to hunk
This binding to provide the list of partitions that kernel drivers may need to access. Signed-off-by: Sudeep Holla <redacted> --- .../devicetree/bindings/arm/arm,ffa.yaml | 57 +++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 Documentation/devicetree/bindings/arm/arm,ffa.yamldiff --git a/Documentation/devicetree/bindings/arm/arm,ffa.yaml b/Documentation/devicetree/bindings/arm/arm,ffa.yaml new file mode 100644 index 000000000000..42ed33464ba7 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/arm,ffa.yaml@@ -0,0 +1,57 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/arm/arm,ffa.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Arm Firmware Framework for Arm v8-A (in-kernel users) + +maintainers: + - Sudeep Holla <sudeep.holla@arm.com> + +description: | + Firmware frameworks implementing partition according to the FF-A + specification defined by ARM document number ARM DEN 0077A ("Arm Firmware + Framework for Arm v8-A") [0], providing services to be used by other + partitions. + + [0] https://developer.arm.com/docs/den0077/latest + +properties: + $nodename: + const: ffa + + compatible: + oneOf: + - const: arm,ffa-1.0 + +patternProperties: + "^ffa-partition-[0-9]+$": + type: object + description: One or more child nodes, each describing an FFA partition. + properties: + $nodename: + const: ffa_partition + + compatible: + const: arm,ffa-1.0-partition + + uuid: + $ref: '/schemas/types.yaml#definitions/string' + description: | + The 128-bit UUID [2] of the service implemented by this partition. + + [2] https://tools.ietf.org/html/rfc4122 + +additionalProperties: false + +examples: + - | + ffa { + compatible = "arm,ffa-1.0"; + + ffa-partition-0 { + compatible = "arm,ffa-1.0-partition"; + uuid = "12345678-9abc-def0-1234-56789abcdef0"; + }; + }; --2.25.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
_______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel