From: Oleksii Moisieiev Oleksii_Moisieiev@epam.com
Introducing of the generic access controllers 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 Reviewed-by: Rob Herring robh@kernel.org ---
Changes in V9: - Added Rob's review tag
Changes in V6: - Renamed access-controller to access-controllers - Example updated - Removal of access-control-provider property
Changes in V5: - Diffs with [1] - Discarded the [IGNORE] tag as the patch is now part of the patchset
.../access-controllers.yaml | 84 +++++++++++++++++++ 1 file changed, 84 insertions(+) create mode 100644 Documentation/devicetree/bindings/access-controllers/access-controllers.yaml
diff --git a/Documentation/devicetree/bindings/access-controllers/access-controllers.yaml b/Documentation/devicetree/bindings/access-controllers/access-controllers.yaml new file mode 100644 index 000000000000..99e2865f0e46 --- /dev/null +++ b/Documentation/devicetree/bindings/access-controllers/access-controllers.yaml @@ -0,0 +1,84 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/access-controllers/access-controllers.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Generic Domain Access Controllers + +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 binding can be used to bind devices to their access + controller provided by access-controllers 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": + description: + Number of cells in an access-controllers specifier; + Can be any value as specified by device tree binding documentation + of a particular provider. The node is an access controller. + + access-controller-names: + $ref: /schemas/types.yaml#/definitions/string-array + description: + A list of access-controllers names, sorted in the same order as + access-controllers entries. Consumer drivers will use + access-controller-names to match with existing access-controllers entries. + + access-controllers: + $ref: /schemas/types.yaml#/definitions/phandle-array + description: + A list of access controller specifiers, as defined by the + bindings of the access-controllers provider. + +additionalProperties: true + +examples: + - | + clock_controller: access-controllers@50000 { + reg = <0x50000 0x400>; + #access-controller-cells = <2>; + }; + + bus_controller: bus@60000 { + reg = <0x60000 0x10000>; + #address-cells = <1>; + #size-cells = <1>; + ranges; + #access-controller-cells = <3>; + + uart4: serial@60100 { + reg = <0x60100 0x400>; + clocks = <&clk_serial>; + access-controllers = <&clock_controller 1 2>, + <&bus_controller 1 3 5>; + access-controller-names = "clock", "bus"; + }; + };