| Message ID | 20230929142852.578394-2-gatien.chevallier@foss.st.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v5,01/11] dt-bindings: document generic access controller | expand |
Hi Rob, On 10/2/23 19:30, Rob Herring wrote: > On Fri, Sep 29, 2023 at 04:28:42PM +0200, Gatien Chevallier wrote: >> From: Oleksii Moisieiev <Oleksii_Moisieiev@epam.com> >> >> Introducing of the generic access controller bindings for the >> access controller provider and consumer devices. Those bindings are >> intended to allow a better handling of accesses to resources in a >> hardware architecture supporting several compartments. >> >> This patch is based on [1]. It is integrated in this patchset as it >> provides a use-case for it. >> >> Diffs with [1]: >> - Rename feature-domain* properties to access-control* to narrow >> down the scope of the binding >> - YAML errors and typos corrected. >> - Example updated >> - Some rephrasing in the binding description >> >> [1]: https://lore.kernel.org/lkml/0c0a82bb-18ae-d057-562b >> >> Signed-off-by: Oleksii Moisieiev <oleksii_moisieiev@epam.com> >> Signed-off-by: Gatien Chevallier <gatien.chevallier@foss.st.com> >> >> --- >> Changes in V5: >> - Diffs with [1] >> - Discarded the [IGNORE] tag as the patch is now part of the >> patchset >> >> .../access-controllers/access-controller.yaml | 90 +++++++++++++++++++ >> 1 file changed, 90 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/access-controllers/access-controller.yaml >> >> diff --git a/Documentation/devicetree/bindings/access-controllers/access-controller.yaml b/Documentation/devicetree/bindings/access-controllers/access-controller.yaml >> new file mode 100644 >> index 000000000000..9d305fccc333 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/access-controllers/access-controller.yaml >> @@ -0,0 +1,90 @@ >> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) >> +%YAML 1.2 >> +--- >> +$id: http://devicetree.org/schemas/access-controllers/access-controller.yaml# >> +$schema: http://devicetree.org/meta-schemas/core.yaml# >> + >> +title: Generic Domain Access Controller >> + >> +maintainers: >> + - Oleksii Moisieiev <oleksii_moisieiev@epam.com> >> + >> +description: |+ >> + Common access controllers properties >> + >> + Access controllers are in charge of stating which of the hardware blocks under >> + their responsibility (their domain) can be accesssed by which compartment. A >> + compartment can be a cluster of CPUs (or coprocessors), a range of addresses >> + or a group of hardware blocks. An access controller's domain is the set of >> + resources covered by the access controller. >> + >> + This device tree bindings can be used to bind devices to their access >> + controller provided by access-controller property. In this case, the device is >> + a consumer and the access controller is the provider. >> + >> + An access controller can be represented by any node in the device tree and >> + can provide one or more configuration parameters, needed to control parameters >> + of the consumer device. A consumer node can refer to the provider by phandle >> + and a set of phandle arguments, specified by '#access-controller-cells' >> + property in the access controller node. >> + >> + Access controllers are typically used to set/read the permissions of a >> + hardware block and grant access to it. Any of which depends on the access >> + controller. The capabilities of each access controller are defined by the >> + binding of the access controller device. >> + >> + Each node can be a consumer for the several access controllers. >> + >> +# always select the core schema >> +select: true >> + >> +properties: >> + "#access-controller-cells": >> + $ref: /schemas/types.yaml#/definitions/uint32 > > Drop. "#.*-cells" already defines the type. > Ok, I will drop it for V6 >> + description: >> + Number of cells in a access-controller specifier; >> + Can be any value as specified by device tree binding documentation >> + of a particular provider. >> + >> + access-control-provider: >> + description: >> + Indicates that the node is an access controller. > > Drop. The presence of "#access-controller-cells" is enough to do that. > Ok, I wasn't sure. I'll will drop it for V6 >> + >> + access-controller-names: >> + $ref: /schemas/types.yaml#/definitions/string-array >> + description: >> + A list of access-controller names, sorted in the same order as >> + access-controller entries. Consumer drivers will use >> + access-controller-names to match with existing access-controller entries. >> + >> + access-controller: > > For consistency with other provider bindings: access-controllers > Ack >> + $ref: /schemas/types.yaml#/definitions/phandle-array >> + description: >> + A list of access controller specifiers, as defined by the >> + bindings of the access-controller provider. >> + >> +additionalProperties: true >> + >> +examples: >> + - | >> + uart_controller: access-controller@50000 { >> + reg = <0x50000 0x10>; >> + access-control-provider; >> + #access-controller-cells = <2>; >> + }; >> + >> + bus_controller: bus@60000 { >> + reg = <0x60000 0x10000>; >> + #address-cells = <1>; >> + #size-cells = <1>; >> + ranges; >> + access-control-provider; >> + #access-controller-cells = <3>; >> + >> + uart4: serial@60100 { >> + reg = <0x60100 0x400>; >> + access-controller = <&uart_controller 1 2>, >> + <&bus_controller 1 3 5>; >> + access-controller-names = "controller", "bus-controller"; > > Not great names. It should indicate what access is being controlled > locally. Perhaps "reg" for register access, "dma" or "bus" for bus > master access. (Not sure what your uart_controller is controlling access > to.) > > Rob Yes, I agree it's poor naming. I'll come up with something more adequate. Thank you for the input. Best regards, Gatien
diff --git a/Documentation/devicetree/bindings/access-controllers/access-controller.yaml b/Documentation/devicetree/bindings/access-controllers/access-controller.yaml new file mode 100644 index 000000000000..9d305fccc333 --- /dev/null +++ b/Documentation/devicetree/bindings/access-controllers/access-controller.yaml @@ -0,0 +1,90 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/access-controllers/access-controller.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Generic Domain Access Controller + +maintainers: + - Oleksii Moisieiev <oleksii_moisieiev@epam.com> + +description: |+ + Common access controllers properties + + Access controllers are in charge of stating which of the hardware blocks under + their responsibility (their domain) can be accesssed by which compartment. A + compartment can be a cluster of CPUs (or coprocessors), a range of addresses + or a group of hardware blocks. An access controller's domain is the set of + resources covered by the access controller. + + This device tree bindings can be used to bind devices to their access + controller provided by access-controller property. In this case, the device is + a consumer and the access controller is the provider. + + An access controller can be represented by any node in the device tree and + can provide one or more configuration parameters, needed to control parameters + of the consumer device. A consumer node can refer to the provider by phandle + and a set of phandle arguments, specified by '#access-controller-cells' + property in the access controller node. + + Access controllers are typically used to set/read the permissions of a + hardware block and grant access to it. Any of which depends on the access + controller. The capabilities of each access controller are defined by the + binding of the access controller device. + + Each node can be a consumer for the several access controllers. + +# always select the core schema +select: true + +properties: + "#access-controller-cells": + $ref: /schemas/types.yaml#/definitions/uint32 + description: + Number of cells in a access-controller specifier; + Can be any value as specified by device tree binding documentation + of a particular provider. + + access-control-provider: + description: + Indicates that the node is an access controller. + + access-controller-names: + $ref: /schemas/types.yaml#/definitions/string-array + description: + A list of access-controller names, sorted in the same order as + access-controller entries. Consumer drivers will use + access-controller-names to match with existing access-controller entries. + + access-controller: + $ref: /schemas/types.yaml#/definitions/phandle-array + description: + A list of access controller specifiers, as defined by the + bindings of the access-controller provider. + +additionalProperties: true + +examples: + - | + uart_controller: access-controller@50000 { + reg = <0x50000 0x10>; + access-control-provider; + #access-controller-cells = <2>; + }; + + bus_controller: bus@60000 { + reg = <0x60000 0x10000>; + #address-cells = <1>; + #size-cells = <1>; + ranges; + access-control-provider; + #access-controller-cells = <3>; + + uart4: serial@60100 { + reg = <0x60100 0x400>; + access-controller = <&uart_controller 1 2>, + <&bus_controller 1 3 5>; + access-controller-names = "controller", "bus-controller"; + }; + };