[PATCH v6 0/8] ARM64: juno: add SCPI mailbox protocol, clock and CPUFreq support

[PATCH v6 0/8] ARM64: juno: add SCPI mailbox protocol, clock and CPUFreq support

[Sudeep Holla]

Hi ARM-SoC guys,

It has been on the list for a while and have got all the necessary ACKs.
Can you please pull this series for v4.3 ?

Regards,
Sudeep

This patch series adds support for:
  1. SCPI(System Control and Power Interface) mailbox protocol driver.
     It uses ARM MHU mailbox controller driver on Juno but can work with
     any mailbox controllers using standard mailbox APIs
  2. Add support for clocks provided by SCP firmware through the SCPI
     interface
  3. Using the existing arm_big_little cpufreq driver and the newly
     added SCPI clock driver, it also adds support for CPU DVFS on
     ARM64 JUNO development platforms.

The SCPI protocol document is available @[1],[2]

Changes v5->v6:
	- Minor review comments on clock bindings and clock driver
	- Added all the ACKs necessary

Changes v4->v5:
	- Updated the SCPI clock bindings to correct the clock specifier
	  usage and other minor updates as per review feedback
	- Updated clock driver to use SCPI specifier clock specifier
	  decode function
	- Minor reshuffling in Juno DTS files, no functionality change

Changes v3->v4:
	- Updated the SCPI binding based on MarkR's feedback
	- Updated SCPI clock driver to incorporate Stephen Boyd's review
	  comments + used clk_set_rate_range to limit the clock range
	- Since no major changes are expected in SCPI DT, updated the
	  Juno DTS to support SCPI and dependent device nodes.

Changes v2->v3:
	- Minor fix in SCPI driver and added Tixy's reviewed-by tag
	- Updated scpi clock driver to incorporate all the comments from
	  Stephen
	- Added Viresh's ack

Changes v1->v2:
	- Updated the token handling in scpi driver as per Tixy's
	  suggestion along with other review comments
	- Removed multiple drivers in scpi clock as Lorenzo suggested
	- Added free_opp_table in scpi-cpufreq as Viresh suggested
	- Separated the DT binding document
	- Moved SCPI protocol driver to drivers/firmware

[1] http://community.arm.com/servlet/JiveServlet/download/8401-45-18326/DUI0922B_scp_message_interface.pdf
[2] https://wiki.linaro.org/ARM/Juno?action=AttachFile&do=get&target=DUI0922B_scp_message_interface.pdf
v1: https://lkml.org/lkml/2015/4/27/232
v2: https://lkml.org/lkml/2015/5/14/470
v3: https://lkml.org/lkml/2015/5/27/220
v4: https://lkml.org/lkml/2015/6/8/178
v5: https://lkml.org/lkml/2015/7/23/270

Cc: devicetree@vger.kernel.org
Cc: linux-clk@vger.kernel.org
Cc: linux-pm@vger.kernel.org

Sudeep Holla (8):
  Documentation: add DT binding for ARM System Control and Power
    Interface(SCPI) protocol
  firmware: add support for ARM System Control and Power Interface(SCPI)
    protocol
  clk: add support for clocks provided by SCP(System Control Processor)
  clk: scpi: add support for cpufreq virtual device
  cpufreq: arm_big_little: add SCPI interface driver
  arm64: dts: add SRAM, MHU mailbox and SCPI support on Juno
  arm64: dts: add CPU topology on Juno
  arm64: dts: add clock support for all the cpus

 Documentation/devicetree/bindings/arm/arm,scpi.txt | 150 +++++
 MAINTAINERS                                        |  10 +
 arch/arm64/boot/dts/arm/juno-base.dtsi             |  54 ++
 arch/arm64/boot/dts/arm/juno-r1.dts                |  32 +
 arch/arm64/boot/dts/arm/juno.dts                   |  32 +
 drivers/clk/Kconfig                                |  10 +
 drivers/clk/Makefile                               |   1 +
 drivers/clk/clk-scpi.c                             | 325 ++++++++++
 drivers/cpufreq/Kconfig.arm                        |   9 +
 drivers/cpufreq/Makefile                           |   1 +
 drivers/cpufreq/scpi-cpufreq.c                     | 124 ++++
 drivers/firmware/Kconfig                           |  19 +
 drivers/firmware/Makefile                          |   1 +
 drivers/firmware/arm_scpi.c                        | 711 +++++++++++++++++++++
 include/linux/scpi_protocol.h                      |  61 ++
 15 files changed, 1540 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/arm/arm,scpi.txt
 create mode 100644 drivers/clk/clk-scpi.c
 create mode 100644 drivers/cpufreq/scpi-cpufreq.c
 create mode 100644 drivers/firmware/arm_scpi.c
 create mode 100644 include/linux/scpi_protocol.h

-- 
1.9.1

[PATCH v6 1/8] Documentation: add DT binding for ARM System Control and Power Interface(SCPI) protocol

[Sudeep Holla]

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@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
CC: Jassi Brar <jassisinghbrar@gmail.com>
Cc: Liviu Dudau <Liviu.Dudau@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Jon Medhurst (Tixy) <tixy@linaro.org>
Cc: devicetree@vger.kernel.org
---
 Documentation/devicetree/bindings/arm/arm,scpi.txt | 150 +++++++++++++++++++++
 MAINTAINERS                                        |   6 +
 2 files changed, 156 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..e309249db536
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/arm,scpi.txt
@@ -0,0 +1,150 @@
+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 1. Contains the Clock ID value used by SCPI commands.
+- clock-output-names : shall be the corresponding names of the outputs.
+- clock-indices: The identifying number for the clocks(i.e.clock_id) in the
+	node. It can be non linear and hence provide the mapping of identifiers
+	into the clock-output-names array.
+
+SRAM and Shared Memory for SCPI
+-------------------------------
+
+A small area of SRAM is reserved for SCPI communication between application
+processors and SCP.
+
+Required properties:
+- compatible : should be "arm,juno-sram-ns" for Non-secure SRAM on Juno
+
+The rest of the properties should follow the generic mmio-sram description
+found in ../../misc/sysram.txt
+
+Each sub-node represents the reserved area for SCPI.
+
+Required sub-node properties:
+- reg : The base offset and size of the reserved area with the SRAM
+- compatible : should be "arm,juno-scp-shmem" for Non-secure SRAM based
+	       shared memory on Juno platforms
+
+[0] http://community.arm.com/servlet/JiveServlet/download/8401-45-18326/DUI0922B_scp_message_interface.pdf
+[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+
+Example:
+
+sram: sram@50000000 {
+	compatible = "arm,juno-sram-ns", "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,juno-scp-shmem";
+		reg = <0x0 0x200>;
+	};
+
+	cpu_scp_hpri: scp-shmem@200 {
+		compatible = "arm,juno-scp-shmem";
+		reg = <0x200 0x200>;
+	};
+};
+
+mailbox: mailbox0@40000000 {
+	....
+	#mbox-cells = <1>;
+};
+
+scpi_protocol: scpi@2e000000 {
+	compatible = "arm,scpi";
+	mboxes = <&mailbox 0 &mailbox 1>;
+	shmem = <&cpu_scp_lpri &cpu_scp_hpri>;
+
+	clocks {
+		compatible = "arm,scpi-clocks";
+
+		scpi_dvfs: scpi_clocks@0 {
+			compatible = "arm,scpi-dvfs-clocks";
+			#clock-cells = <1>;
+			clock-indices = <0>, <1>, <2>;
+			clock-output-names = "atlclk", "aplclk","gpuclk";
+		};
+		scpi_clk: scpi_clocks@3 {
+			compatible = "arm,scpi-variable-clocks";
+			#clock-cells = <1>;
+			clock-indices = <3>, <4>;
+			clock-output-names = "pxlclk0", "pxlclk1";
+		};
+	};
+};
+
+cpu@0 {
+	...
+	reg = <0 0>;
+	clocks = <&scpi_dvfs 0>;
+};
+
+hdlcd@7ff60000 {
+	...
+	reg = <0 0x7ff60000 0 0x1000>;
+	clocks = <&scpi_clk 4>;
+};
+
+In the above example, the #clock-cells is set to 1 as required.
+scpi_dvfs has 3 output clocks namely: atlclk, aplclk, and gpuclk with 0,
+1 and 2 as clock-indices. scpi_clk has 2 output clocks namely: pxlclk0
+and pxlclk1 with 3 and 4 as clock-indices.
+
+The first consumer in the example is cpu@0 and it has '0' as the clock
+specifier which points to the first entry in the output clocks of
+scpi_dvfs i.e. "atlclk".
+
+Similarly the second example is hdlcd@7ff60000 and it has pxlclk1 as input
+clock. '4' in the clock specifier here points to the second entry
+in the output clocks of scpi_clocks  i.e. "pxlclk1"
diff --git a/MAINTAINERS b/MAINTAINERS
index 9289ecb57b68..7dadaa87afac 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8960,6 +8960,12 @@ W:	http://www.sunplus.com
 S:	Supported
 F:	arch/score/
 
+SYSTEM CONTROL & POWER INTERFACE (SCPI) Message Protocol drivers
+M:	Sudeep Holla <sudeep.holla@arm.com>
+L:	linux-arm-kernel@lists.infradead.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/arm/arm,scpi.txt
+
 SCSI CDROM DRIVER
 M:	Jens Axboe <axboe@kernel.dk>
 L:	linux-scsi@vger.kernel.org
-- 
1.9.1

Re: [PATCH v6 0/8] ARM64: juno: add SCPI mailbox protocol, clock and CPUFreq support

[Liviu Dudau]

On Fri, Jul 31, 2015 at 06:43:03PM +0100, Sudeep Holla wrote:
> Hi ARM-SoC guys,
> 
> It has been on the list for a while and have got all the necessary ACKs.
> Can you please pull this series for v4.3 ?
> 
> Regards,
> Sudeep
> 
> This patch series adds support for:
>   1. SCPI(System Control and Power Interface) mailbox protocol driver.
>      It uses ARM MHU mailbox controller driver on Juno but can work with
>      any mailbox controllers using standard mailbox APIs
>   2. Add support for clocks provided by SCP firmware through the SCPI
>      interface
>   3. Using the existing arm_big_little cpufreq driver and the newly
>      added SCPI clock driver, it also adds support for CPU DVFS on
>      ARM64 JUNO development platforms.

Hi Sudeep,

Is there a branch where I can pull this series from?

Best regards,
Liviu

> 
> The SCPI protocol document is available @[1],[2]
> 
> Changes v5->v6:
> 	- Minor review comments on clock bindings and clock driver
> 	- Added all the ACKs necessary
> 
> Changes v4->v5:
> 	- Updated the SCPI clock bindings to correct the clock specifier
> 	  usage and other minor updates as per review feedback
> 	- Updated clock driver to use SCPI specifier clock specifier
> 	  decode function
> 	- Minor reshuffling in Juno DTS files, no functionality change
> 
> Changes v3->v4:
> 	- Updated the SCPI binding based on MarkR's feedback
> 	- Updated SCPI clock driver to incorporate Stephen Boyd's review
> 	  comments + used clk_set_rate_range to limit the clock range
> 	- Since no major changes are expected in SCPI DT, updated the
> 	  Juno DTS to support SCPI and dependent device nodes.
> 
> Changes v2->v3:
> 	- Minor fix in SCPI driver and added Tixy's reviewed-by tag
> 	- Updated scpi clock driver to incorporate all the comments from
> 	  Stephen
> 	- Added Viresh's ack
> 
> Changes v1->v2:
> 	- Updated the token handling in scpi driver as per Tixy's
> 	  suggestion along with other review comments
> 	- Removed multiple drivers in scpi clock as Lorenzo suggested
> 	- Added free_opp_table in scpi-cpufreq as Viresh suggested
> 	- Separated the DT binding document
> 	- Moved SCPI protocol driver to drivers/firmware
> 
> [1] http://community.arm.com/servlet/JiveServlet/download/8401-45-18326/DUI0922B_scp_message_interface.pdf
> [2] https://wiki.linaro.org/ARM/Juno?action=AttachFile&do=get&target=DUI0922B_scp_message_interface.pdf
> v1: https://lkml.org/lkml/2015/4/27/232
> v2: https://lkml.org/lkml/2015/5/14/470
> v3: https://lkml.org/lkml/2015/5/27/220
> v4: https://lkml.org/lkml/2015/6/8/178
> v5: https://lkml.org/lkml/2015/7/23/270
> 
> Cc: devicetree@vger.kernel.org
> Cc: linux-clk@vger.kernel.org
> Cc: linux-pm@vger.kernel.org
> 
> Sudeep Holla (8):
>   Documentation: add DT binding for ARM System Control and Power
>     Interface(SCPI) protocol
>   firmware: add support for ARM System Control and Power Interface(SCPI)
>     protocol
>   clk: add support for clocks provided by SCP(System Control Processor)
>   clk: scpi: add support for cpufreq virtual device
>   cpufreq: arm_big_little: add SCPI interface driver
>   arm64: dts: add SRAM, MHU mailbox and SCPI support on Juno
>   arm64: dts: add CPU topology on Juno
>   arm64: dts: add clock support for all the cpus
> 
>  Documentation/devicetree/bindings/arm/arm,scpi.txt | 150 +++++
>  MAINTAINERS                                        |  10 +
>  arch/arm64/boot/dts/arm/juno-base.dtsi             |  54 ++
>  arch/arm64/boot/dts/arm/juno-r1.dts                |  32 +
>  arch/arm64/boot/dts/arm/juno.dts                   |  32 +
>  drivers/clk/Kconfig                                |  10 +
>  drivers/clk/Makefile                               |   1 +
>  drivers/clk/clk-scpi.c                             | 325 ++++++++++
>  drivers/cpufreq/Kconfig.arm                        |   9 +
>  drivers/cpufreq/Makefile                           |   1 +
>  drivers/cpufreq/scpi-cpufreq.c                     | 124 ++++
>  drivers/firmware/Kconfig                           |  19 +
>  drivers/firmware/Makefile                          |   1 +
>  drivers/firmware/arm_scpi.c                        | 711 +++++++++++++++++++++
>  include/linux/scpi_protocol.h                      |  61 ++
>  15 files changed, 1540 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/arm/arm,scpi.txt
>  create mode 100644 drivers/clk/clk-scpi.c
>  create mode 100644 drivers/cpufreq/scpi-cpufreq.c
>  create mode 100644 drivers/firmware/arm_scpi.c
>  create mode 100644 include/linux/scpi_protocol.h
> 
> -- 
> 1.9.1
> 

-- 
====================
| I would like to |
| fix the world,  |
| but they're not |
| giving me the   |
 \ source code!  /
  ---------------
    ¯\_(ツ)_/¯

Re: [PATCH v6 0/8] ARM64: juno: add SCPI mailbox protocol, clock and CPUFreq support

[Sudeep Holla]

On 03/08/15 11:18, Liviu Dudau wrote:
> On Fri, Jul 31, 2015 at 06:43:03PM +0100, Sudeep Holla wrote:
>> Hi ARM-SoC guys,
>>
>> It has been on the list for a while and have got all the necessary ACKs.
>> Can you please pull this series for v4.3 ?
>>
>> Regards,
>> Sudeep
>>
>> This patch series adds support for:
>>    1. SCPI(System Control and Power Interface) mailbox protocol driver.
>>       It uses ARM MHU mailbox controller driver on Juno but can work with
>>       any mailbox controllers using standard mailbox APIs
>>    2. Add support for clocks provided by SCP firmware through the SCPI
>>       interface
>>    3. Using the existing arm_big_little cpufreq driver and the newly
>>       added SCPI clock driver, it also adds support for CPU DVFS on
>>       ARM64 JUNO development platforms.
>
> Hi Sudeep,
>
> Is there a branch where I can pull this series from?
>

Yes, you can pull from
git://linux-arm.org/linux-skn.git juno_dvfs

Regards,
Sudeep

Re: [PATCH v6 0/8] ARM64: juno: add SCPI mailbox protocol, clock and CPUFreq support

[Sudeep Holla]

Hi Olof,

On 31/07/15 18:43, Sudeep Holla wrote:
> Hi ARM-SoC guys,
>
> It has been on the list for a while and have got all the necessary
> ACKs. Can you please pull this series for v4.3 ?
>

Can you pull this patch series directly from the mail or do you prefer
pull-request ?

Regards,
Sudeep

Re: [PATCH v6 0/8] ARM64: juno: add SCPI mailbox protocol, clock and CPUFreq support

[Sudeep Holla]

Hi Olof,

On 05/08/15 10:59, Sudeep Holla wrote:
> Hi Olof,
>
> On 31/07/15 18:43, Sudeep Holla wrote:
>> Hi ARM-SoC guys,
>>
>> It has been on the list for a while and have got all the necessary
>> ACKs. Can you please pull this series for v4.3 ?
>>
>
> Can you pull this patch series directly from the mail or do you prefer
> pull-request ?
>

Any issue with this series ? Let me know. I did send a pull request also
but I haven't got any response so far. Sorry for the nag.

Regards,
Sudeep