On 31/07/15 17:00, Mark Rutland wrote:
Hi, On Thu, Jul 23, 2015 at 12:10:21PM +0100, Sudeep Holla wrote:This patch adds devicetree binding for System Control and Power Interface (SCPI) Message Protocol used between the Application Cores(AP) and the System Control Processor(SCP). The MHU peripheral provides a mechanism for inter-processor communication between SCP's M3 processor and AP. SCP offers control and management of the core/cluster power states, various power domain DVFS including the core/cluster, certain system clocks configuration, thermal sensors and many others. Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx> Cc: Rob Herring <robh+dt@xxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> CC: Jassi Brar <jassisinghbrar@xxxxxxxxx> Cc: Liviu Dudau <Liviu.Dudau@xxxxxxx> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> Cc: Jon Medhurst (Tixy) <tixy@xxxxxxxxxx> Cc: devicetree@xxxxxxxxxxxxxxx --- Documentation/devicetree/bindings/arm/arm,scpi.txt | 151 +++++++++++++++++++++ MAINTAINERS | 6 + 2 files changed, 157 insertions(+) create mode 100644 Documentation/devicetree/bindings/arm/arm,scpi.txt diff --git a/Documentation/devicetree/bindings/arm/arm,scpi.txt b/Documentation/devicetree/bindings/arm/arm,scpi.txt new file mode 100644 index 000000000000..e21cce646561 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/arm,scpi.txt @@ -0,0 +1,151 @@ +System Control and Power Interface (SCPI) Message Protocol +---------------------------------------------------------- + +Firmware implementing the SCPI described in ARM document number ARM DUI 0922B +("ARM Compute Subsystem SCP: Message Interface Protocols")[0] can be used +by Linux to initiate various system control and power operations. + +Required properties: + +- compatible : should be "arm,scpi" +- mboxes: List of phandle and mailbox channel specifiers + All the channels reserved by remote SCP firmware for use by + SCPI message protocol should be specified in any order +- shmem : List of phandle pointing to the shared memory(SHM) area between the + processors using these mailboxes for IPC, one for each mailbox + SHM can be any memory reserved for the purpose of this communication + between the processors. + +See Documentation/devicetree/bindings/mailbox/mailbox.txt +for more details about the generic mailbox controller and +client driver bindings. + +Clock bindings for the clocks based on SCPI Message Protocol +------------------------------------------------------------ + +This binding uses the common clock binding[1]. + +Container Node +============== +Required properties: +- compatible : should be "arm,scpi-clocks" + All the clocks provided by SCP firmware via SCPI message + protocol much be listed as sub-nodes under this node. + +Sub-nodes +========= +Required properties: +- compatible : shall include one of the following + "arm,scpi-dvfs-clocks" - all the clocks that are variable and index based. + These clocks don't provide an entire range of values between the + limits but only discrete points within the range. The firmware + provides the mapping for each such operating frequency and the + index associated with it. The firmware also manages the + voltage scaling appropriately with the clock scaling. + "arm,scpi-variable-clocks" - all the clocks that are variable and provide full + range within the specified range. The firmware provides the + range of values within a specified range. + +Other required properties for all clocks(all from common clock binding): +- #clock-cells : should be set to 1 as each of the SCPI clocks have multiple + outputs.Could you change this to: #clock-cells: Should be 1. Contains the Clock ID value used by SCPI commands.
Changed now.
That will make it clear what value should be used when writing a dts (the raw value commands use, as opposed to some logical abstraction thereof).
Agreed.
With that: Acked-by: Mark Rutland <mark.rutland@xxxxxxx>
Thanks. Regards, Sudeep -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
