From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sudeep Holla Subject: Re: [PATCH v5 1/8] Documentation: add DT binding for ARM System Control and Power Interface(SCPI) protocol Date: Fri, 31 Jul 2015 17:07:26 +0100 Message-ID: <55BB9D3E.1000605@arm.com> References: <1437649828-14540-1-git-send-email-sudeep.holla@arm.com> <1437649828-14540-2-git-send-email-sudeep.holla@arm.com> <20150731160027.GG25118@leverpostej> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20150731160027.GG25118@leverpostej> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Mark Rutland Cc: Sudeep Holla , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Liviu Dudau , Punit Agrawal , "Jon Medhurst (Tixy)" , Lorenzo Pieralisi , Arnd Bergmann , Olof Johansson , Kevin Hilman , Rob Herring , Jassi Brar , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: devicetree@vger.kernel.org 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 >> Cc: Rob Herring >> Cc: Mark Rutland >> CC: Jassi Brar >> Cc: Liviu Dudau >> Cc: Lorenzo Pieralisi >> Cc: Jon Medhurst (Tixy) >> Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org >> --- >> 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 > Thanks. Regards, Sudeep -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752959AbbGaQHc (ORCPT ); Fri, 31 Jul 2015 12:07:32 -0400 Received: from foss.arm.com ([217.140.101.70]:46250 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751578AbbGaQHa (ORCPT ); Fri, 31 Jul 2015 12:07:30 -0400 Message-ID: <55BB9D3E.1000605@arm.com> Date: Fri, 31 Jul 2015 17:07:26 +0100 From: Sudeep Holla User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.8.0 MIME-Version: 1.0 To: Mark Rutland CC: Sudeep Holla , "linux-kernel@vger.kernel.org" , Liviu Dudau , Punit Agrawal , "Jon Medhurst (Tixy)" , Lorenzo Pieralisi , Arnd Bergmann , Olof Johansson , Kevin Hilman , Rob Herring , Jassi Brar , "devicetree@vger.kernel.org" Subject: Re: [PATCH v5 1/8] Documentation: add DT binding for ARM System Control and Power Interface(SCPI) protocol References: <1437649828-14540-1-git-send-email-sudeep.holla@arm.com> <1437649828-14540-2-git-send-email-sudeep.holla@arm.com> <20150731160027.GG25118@leverpostej> In-Reply-To: <20150731160027.GG25118@leverpostej> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 >> Cc: Rob Herring >> Cc: Mark Rutland >> CC: Jassi Brar >> Cc: Liviu Dudau >> Cc: Lorenzo Pieralisi >> Cc: Jon Medhurst (Tixy) >> Cc: devicetree@vger.kernel.org >> --- >> 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 > Thanks. Regards, Sudeep