[v5,01/11] dt-bindings: document generic access controller
Commit Message
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
Comments
On 9/29/23 17:35, Rob Herring wrote:
>
> On Fri, 29 Sep 2023 16:28:42 +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
>>
>
> My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
> on your patch (DT_CHECKER_FLAGS is new in v5.13):
>
> yamllint warnings/errors:
>
> dtschema/dtc warnings/errors:
> /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/access-controllers/access-controller.yaml: access-control-provider: missing type definition
>
> doc reference errors (make refcheckdocs):
>
> See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20230929142852.578394-2-gatien.chevallier@foss.st.com
>
> The base for the series is generally the latest rc1. A different dependency
> should be noted in *this* patch.
>
> If you already ran 'make dt_binding_check' and didn't see the above
> error(s), then make sure 'yamllint' is installed and dt-schema is up to
> date:
>
> pip3 install dtschema --upgrade
>
> Please check and re-submit after running the above command yourself. Note
> that DT_SCHEMA_FILES can be set to your schema file to speed up checking
> your schema. However, it must be unset to test all examples with your schema.
>
Hi Rob,
Running:
1- make dt_binding_check | grep access-control
2- make dt_binding_check
DT_SCHEMA_FILES=Documentation/devicetree/bindings/access-controllers/access-controller.yaml
from Krzysztof's slideset
with
pip3 show dtschema
Name: dtschema
Version: 2023.9
and
pip3 show yamllint
Name: yamllint
Version: 1.32.0
I don't see any of the errors reported by the robot. I have to clone
your repository to reproduce it.
Should I resubmit with a clean dt-check using the latest dtschema?
***********
However, I get:
warning: ignoring duplicate '$id' value
'http://devicetree.org/schemas/reserved-memory/framebuffer.yaml#
warning: ignoring duplicate '$id' value
'http://devicetree.org/schemas/reserved-memory/memory-region.yaml#
warning: ignoring duplicate '$id' value
'http://devicetree.org/schemas/reserved-memory/shared-dma-pool.yaml#
warning: ignoring duplicate '$id' value
'http://devicetree.org/schemas/reserved-memory/reserved-memory.yaml
Above warnings disappears when switching to:
pip3 show dtschema
Name: dtschema
Version: 2023.7
The above YAMLs seem to be duplicated in dtschema's latest version.
I guess it's a synchro that needs to be done since:
https://lore.kernel.org/all/20230830231758.2561402-2-sjg@chromium.org/
***********
Best regards,
Gatien
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
>> + $ref: /schemas/types.yaml#/definitions/phandle-array
>> + description:
>> + A list of access controller specifiers, as defined by the
>> + bindings of the access-controller provider.
>> +
>> +additionalProperties: true
>> +
>> +examples:
>> + - |
>> + uart_controller: access-controller@50000 {
>> + reg = <0x50000 0x10>;
>> + access-control-provider;
>> + #access-controller-cells = <2>;
>> + };
>> +
>> + bus_controller: bus@60000 {
>> + reg = <0x60000 0x10000>;
>> + #address-cells = <1>;
>> + #size-cells = <1>;
>> + ranges;
>> + access-control-provider;
>> + #access-controller-cells = <3>;
>> +
>> + uart4: serial@60100 {
>> + reg = <0x60100 0x400>;
>> + access-controller = <&uart_controller 1 2>,
>> + <&bus_controller 1 3 5>;
>> + access-controller-names = "controller", "bus-controller";
>
> Not great names. It should indicate what access is being controlled
> locally. Perhaps "reg" for register access, "dma" or "bus" for bus
> master access. (Not sure what your uart_controller is controlling access
> to.)
>
> Rob
Yes, I agree it's poor naming. I'll come up with something more
adequate. Thank you for the input.
Best regards,
Gatien
new file mode 100644
@@ -0,0 +1,90 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$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";
+ };
+ };