From: Etienne Carriere Date: Mon, 21 Feb 2022 08:22:38 +0000 (+0100) Subject: doc: binding: scmi: link to latest Linux kernel binding X-Git-Url: http://git.dujemihanovic.xyz/login.html?a=commitdiff_plain;h=4dea25a00d723425c8e2030a849af77b133dfaa1;p=u-boot.git doc: binding: scmi: link to latest Linux kernel binding Changes SCMI bindings documentation to relate to Linux kernel source tree that recently changed the bindings description to YAML format. Reviewed-by: Patrick Delaunay Signed-off-by: Etienne Carriere --- diff --git a/doc/device-tree-bindings/arm/arm,scmi.txt b/doc/device-tree-bindings/arm/arm,scmi.txt index 92572eabb5..0a7886da24 100644 --- a/doc/device-tree-bindings/arm/arm,scmi.txt +++ b/doc/device-tree-bindings/arm/arm,scmi.txt @@ -1,234 +1,2 @@ -System Control and Management Interface (SCMI) Message Protocol ----------------------------------------------------------- - -The SCMI is intended to allow agents such as OSPM to manage various functions -that are provided by the hardware platform it is running on, including power -and performance functions. - -This binding is intended to define the interface the firmware implementing -the SCMI as described in ARM document number ARM DEN 0056A ("ARM System Control -and Management Interface Platform Design Document")[0] provide for OSPM in -the device tree. - -Required properties: - -The scmi node with the following properties shall be under the /firmware/ node. - -- compatible : shall be "arm,scmi" or "arm,scmi-smc" for smc/hvc transports, - or "linaro,scmi-optee" for OP-TEE transport. -- mboxes: List of phandle and mailbox channel specifiers. It should contain - exactly one or two mailboxes, one for transmitting messages("tx") - and another optional for receiving the notifications("rx") if - supported. -- shmem : List of phandle pointing to the shared memory(SHM) area as per - generic mailbox client binding. -- #address-cells : should be '1' if the device has sub-nodes, maps to - protocol identifier for a given sub-node. -- #size-cells : should be '0' as 'reg' property doesn't have any size - associated with it. -- arm,smc-id : SMC id required when using smc or hvc transports -- linaro,optee-channel-id : Channel specifier required when using OP-TEE - transport. - -Optional properties: - -- mbox-names: shall be "tx" or "rx" depending on mboxes entries. - -See Documentation/devicetree/bindings/mailbox/mailbox.txt for more details -about the generic mailbox controller and client driver bindings. -Mailbox doorbell is used as a mechanism to alert the presence of a -messages and/or notification. - -Each protocol supported shall have a sub-node with corresponding compatible -as described in the following sections. If the platform supports dedicated -communication channel for a particular protocol, properties shall be present -in the sub-node corresponding to that protocol. These properties are: -- mboxes, mbox-names and shmem for mailbox transport -- arm,smc-id and shmem for smc/hvc transport -- linaro,optee-channel-id and possibly shmem for OP-TEE transport - -Clock/Performance bindings for the clocks/OPPs based on SCMI Message Protocol ------------------------------------------------------------- - -This binding uses the common clock binding[1]. - -Required properties: -- #clock-cells : Should be 1. Contains the Clock ID value used by SCMI commands. - -Power domain bindings for the power domains based on SCMI Message Protocol ------------------------------------------------------------- - -This binding for the SCMI power domain providers uses the generic power -domain binding[2]. - -Required properties: - - #power-domain-cells : Should be 1. Contains the device or the power - domain ID value used by SCMI commands. - -Regulator bindings for the SCMI Regulator based on SCMI Message Protocol ------------------------------------------------------------- -An SCMI Regulator is permanently bound to a well defined SCMI Voltage Domain, -and should be always positioned as a root regulator. -It does not support any current operation. - -SCMI Regulators are grouped under a 'regulators' node which in turn is a child -of the SCMI Voltage protocol node inside the desired SCMI instance node. - -This binding uses the common regulator binding[6]. - -Required properties: - - reg : shall identify an existent SCMI Voltage Domain. - -Sensor bindings for the sensors based on SCMI Message Protocol --------------------------------------------------------------- -SCMI provides an API to access the various sensors on the SoC. - -Required properties: -- #thermal-sensor-cells: should be set to 1. This property follows the - thermal device tree bindings[3]. - - Valid cell values are raw identifiers (Sensor ID) - as used by the firmware. Refer to platform details - for your implementation for the IDs to use. - -Reset signal bindings for the reset domains based on SCMI Message Protocol ------------------------------------------------------------- - -This binding for the SCMI reset domain providers uses the generic reset -signal binding[5]. - -Required properties: - - #reset-cells : Should be 1. Contains the reset domain ID value used - by SCMI commands. - -SRAM and Shared Memory for SCMI -------------------------------- - -A small area of SRAM is reserved for SCMI communication between application -processors and SCP. - -The properties should follow the generic mmio-sram description found in [4] - -Each sub-node represents the reserved area for SCMI. - -Required sub-node properties: -- reg : The base offset and size of the reserved area with the SRAM -- compatible : should be "arm,scmi-shmem" for Non-secure SRAM based - shared memory - -[0] http://infocenter.arm.com/help/topic/com.arm.doc.den0056a/index.html -[1] Documentation/devicetree/bindings/clock/clock-bindings.txt -[2] Documentation/devicetree/bindings/power/power-domain.yaml -[3] Documentation/devicetree/bindings/thermal/thermal.txt -[4] Documentation/devicetree/bindings/sram/sram.yaml -[5] Documentation/devicetree/bindings/reset/reset.txt -[6] Documentation/devicetree/bindings/regulator/regulator.yaml - -Example: - -sram@50000000 { - compatible = "mmio-sram"; - reg = <0x0 0x50000000 0x0 0x10000>; - - #address-cells = <1>; - #size-cells = <1>; - ranges = <0 0x0 0x50000000 0x10000>; - - cpu_scp_lpri: scp-shmem@0 { - compatible = "arm,scmi-shmem"; - reg = <0x0 0x200>; - }; - - cpu_scp_hpri: scp-shmem@200 { - compatible = "arm,scmi-shmem"; - reg = <0x200 0x200>; - }; -}; - -mailbox@40000000 { - .... - #mbox-cells = <1>; - reg = <0x0 0x40000000 0x0 0x10000>; -}; - -firmware { - - ... - - scmi { - compatible = "arm,scmi"; - mboxes = <&mailbox 0 &mailbox 1>; - mbox-names = "tx", "rx"; - shmem = <&cpu_scp_lpri &cpu_scp_hpri>; - #address-cells = <1>; - #size-cells = <0>; - - scmi_devpd: protocol@11 { - reg = <0x11>; - #power-domain-cells = <1>; - }; - - scmi_dvfs: protocol@13 { - reg = <0x13>; - #clock-cells = <1>; - }; - - scmi_clk: protocol@14 { - reg = <0x14>; - #clock-cells = <1>; - }; - - scmi_sensors0: protocol@15 { - reg = <0x15>; - #thermal-sensor-cells = <1>; - }; - - scmi_reset: protocol@16 { - reg = <0x16>; - #reset-cells = <1>; - }; - - scmi_voltage: protocol@17 { - reg = <0x17>; - - regulators { - regulator_devX: regulator@0 { - reg = <0x0>; - regulator-max-microvolt = <3300000>; - }; - - regulator_devY: regulator@9 { - reg = <0x9>; - regulator-min-microvolt = <500000>; - regulator-max-microvolt = <4200000>; - }; - - ... - }; - }; - }; -}; - -cpu@0 { - ... - reg = <0 0>; - clocks = <&scmi_dvfs 0>; -}; - -hdlcd@7ff60000 { - ... - reg = <0 0x7ff60000 0 0x1000>; - clocks = <&scmi_clk 4>; - power-domains = <&scmi_devpd 1>; - resets = <&scmi_reset 10>; -}; - -thermal-zones { - soc_thermal { - polling-delay-passive = <100>; - polling-delay = <1000>; - /* sensor ID */ - thermal-sensors = <&scmi_sensors0 3>; - ... - }; -}; +See Binding in Linux documentation: +Documentation/devicetree/bindings/firmware/arm,scmi.yaml