[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 5/8] cpufreq: arm_big_little: add SCPI interface driver

[Sudeep Holla]

On some ARM based systems, a separate Cortex-M based System Control
Processor(SCP) provides the overall power, clock, reset and system
control including CPU DVFS. SCPI Message Protocol is used to
communicate with the SCPI.

This patch adds a interface driver for adding OPPs and registering
the arm_big_little cpufreq driver for such systems.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: linux-pm@vger.kernel.org
---
 MAINTAINERS                    |   1 +
 drivers/cpufreq/Kconfig.arm    |   9 +++
 drivers/cpufreq/Makefile       |   1 +
 drivers/cpufreq/scpi-cpufreq.c | 124 +++++++++++++++++++++++++++++++++++++++++
 4 files changed, 135 insertions(+)
 create mode 100644 drivers/cpufreq/scpi-cpufreq.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 690122bb4426..d4b912664a93 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8966,6 +8966,7 @@ L:	linux-arm-kernel@lists.infradead.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/arm/arm,scpi.txt
 F:	drivers/clk/clk-scpi.c
+F:	drivers/cpufreq/scpi-cpufreq.c
 F:	drivers/firmware/arm_scpi.c
 F:	include/linux/scpi_protocol.h
 
diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
index cc8a71c267b8..c46b495169af 100644
--- a/drivers/cpufreq/Kconfig.arm
+++ b/drivers/cpufreq/Kconfig.arm
@@ -24,6 +24,15 @@ config ARM_VEXPRESS_SPC_CPUFREQ
           This add the CPUfreq driver support for Versatile Express
 	  big.LITTLE platforms using SPC for power management.
 
+config ARM_SCPI_CPUFREQ
+        tristate "SCPI based CPUfreq driver"
+	depends on ARM_BIG_LITTLE_CPUFREQ && ARM_SCPI_PROTOCOL
+        help
+	  This adds the CPUfreq driver support for ARM big.LITTLE platforms
+	  using SCPI protocol for CPU power management.
+
+	  This driver uses SCPI Message Protocol driver to interact with the
+	  firmware providing the CPU DVFS functionality.
 
 config ARM_EXYNOS_CPUFREQ
 	tristate "SAMSUNG EXYNOS CPUfreq Driver"
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index 2169bf792db7..7e07f5535c3a 100644
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -78,6 +78,7 @@ obj-$(CONFIG_ARM_SA1110_CPUFREQ)	+= sa1110-cpufreq.o
 obj-$(CONFIG_ARM_SPEAR_CPUFREQ)		+= spear-cpufreq.o
 obj-$(CONFIG_ARM_TEGRA_CPUFREQ)		+= tegra-cpufreq.o
 obj-$(CONFIG_ARM_VEXPRESS_SPC_CPUFREQ)	+= vexpress-spc-cpufreq.o
+obj-$(CONFIG_ARM_SCPI_CPUFREQ)		+= scpi-cpufreq.o
 
 ##################################################################################
 # PowerPC platform drivers
diff --git a/drivers/cpufreq/scpi-cpufreq.c b/drivers/cpufreq/scpi-cpufreq.c
new file mode 100644
index 000000000000..2c3b16fd3a01
--- /dev/null
+++ b/drivers/cpufreq/scpi-cpufreq.c
@@ -0,0 +1,124 @@
+/*
+ * System Control and Power Interface (SCPI) based CPUFreq Interface driver
+ *
+ * It provides necessary ops to arm_big_little cpufreq driver.
+ *
+ * Copyright (C) 2015 ARM Ltd.
+ * Sudeep Holla <sudeep.holla@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/cpufreq.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/scpi_protocol.h>
+#include <linux/types.h>
+
+#include "arm_big_little.h"
+
+static struct scpi_ops *scpi_ops;
+
+static struct scpi_dvfs_info *scpi_get_dvfs_info(struct device *cpu_dev)
+{
+	u8 domain = topology_physical_package_id(cpu_dev->id);
+
+	if (domain < 0)
+		return ERR_PTR(-EINVAL);
+	return scpi_ops->dvfs_get_info(domain);
+}
+
+static int scpi_opp_table_ops(struct device *cpu_dev, bool remove)
+{
+	int idx, ret = 0;
+	struct scpi_opp *opp;
+	struct scpi_dvfs_info *info = scpi_get_dvfs_info(cpu_dev);
+
+	if (IS_ERR(info))
+		return PTR_ERR(info);
+
+	if (!info->opps)
+		return -EIO;
+
+	for (opp = info->opps, idx = 0; idx < info->count; idx++, opp++) {
+		if (remove)
+			dev_pm_opp_remove(cpu_dev, opp->freq);
+		else
+			ret = dev_pm_opp_add(cpu_dev, opp->freq,
+					     opp->m_volt * 1000);
+		if (ret) {
+			dev_warn(cpu_dev, "failed to add opp %uHz %umV\n",
+				 opp->freq, opp->m_volt);
+			while (idx-- > 0)
+				dev_pm_opp_remove(cpu_dev, (--opp)->freq);
+			return ret;
+		}
+	}
+	return ret;
+}
+
+static int scpi_get_transition_latency(struct device *cpu_dev)
+{
+	struct scpi_dvfs_info *info = scpi_get_dvfs_info(cpu_dev);
+
+	if (IS_ERR(info))
+		return PTR_ERR(info);
+	return info->latency;
+}
+
+static int scpi_init_opp_table(struct device *cpu_dev)
+{
+	return scpi_opp_table_ops(cpu_dev, false);
+}
+
+static void scpi_free_opp_table(struct device *cpu_dev)
+{
+	scpi_opp_table_ops(cpu_dev, true);
+}
+
+static struct cpufreq_arm_bL_ops scpi_cpufreq_ops = {
+	.name	= "scpi",
+	.get_transition_latency = scpi_get_transition_latency,
+	.init_opp_table = scpi_init_opp_table,
+	.free_opp_table = scpi_free_opp_table,
+};
+
+static int scpi_cpufreq_probe(struct platform_device *pdev)
+{
+	scpi_ops = get_scpi_ops();
+	if (!scpi_ops)
+		return -EIO;
+
+	return bL_cpufreq_register(&scpi_cpufreq_ops);
+}
+
+static int scpi_cpufreq_remove(struct platform_device *pdev)
+{
+	bL_cpufreq_unregister(&scpi_cpufreq_ops);
+	scpi_ops = NULL;
+	return 0;
+}
+
+static struct platform_driver scpi_cpufreq_platdrv = {
+	.driver = {
+		.name	= "scpi-cpufreq",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= scpi_cpufreq_probe,
+	.remove		= scpi_cpufreq_remove,
+};
+module_platform_driver(scpi_cpufreq_platdrv);
+
+MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
+MODULE_DESCRIPTION("ARM SCPI CPUFreq interface driver");
+MODULE_LICENSE("GPL v2");
-- 
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