[PATCH 0/8] Add cpufreq and cci devfreq for mt8183, and SVS support

[PATCH 0/8] Add cpufreq and cci devfreq for mt8183, and SVS support

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>

MT8183 supports CPU DVFS and CCI DVFS, and LITTLE cpus and CCI are in the same voltage domain.
So, this series is to add drivers to handle the voltage coupling between CPU and CCI DVFS.

For SVS support, add OPP_EVENT_ADJUST_VOLTAGE and corresponding reaction.

Andrew-sh.Cheng (7):
  cpufreq: mediatek: change to regulator_get_optional
  cpufreq: mediatek: add clock enable for intermediate clock
  cpufreq: mediatek: Add support for mt8183
  dt-bindings: devfreq: add compatible for mt8183 cci devfreq
  devfreq: add mediatek cci devfreq
  cpufreq: mediatek: add opp notification for SVS support
  devfreq: cci devfreq register opp notification for SVS support

Stephen Boyd (1):
  PM / OPP: Support adjusting OPP voltages at runtime

 .../bindings/devfreq/mt8183-cci-devfreq.txt        |  20 ++
 drivers/cpufreq/cpufreq-dt-platdev.c               |   1 +
 drivers/cpufreq/mediatek-cpufreq.c                 |  88 +++++-
 drivers/devfreq/Kconfig                            |  10 +
 drivers/devfreq/Makefile                           |   1 +
 drivers/devfreq/mt8183-cci-devfreq.c               | 310 +++++++++++++++++++++
 drivers/opp/core.c                                 |  78 ++++++
 include/linux/pm_opp.h                             |  11 +
 8 files changed, 517 insertions(+), 2 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
 create mode 100644 drivers/devfreq/mt8183-cci-devfreq.c

-- 
2.12.5

[PATCH 0/8] Add cpufreq and cci devfreq for mt8183, and SVS support

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>

MT8183 supports CPU DVFS and CCI DVFS, and LITTLE cpus and CCI are in the same voltage domain.
So, this series is to add drivers to handle the voltage coupling between CPU and CCI DVFS.

For SVS support, add OPP_EVENT_ADJUST_VOLTAGE and corresponding reaction.

Andrew-sh.Cheng (7):
  cpufreq: mediatek: change to regulator_get_optional
  cpufreq: mediatek: add clock enable for intermediate clock
  cpufreq: mediatek: Add support for mt8183
  dt-bindings: devfreq: add compatible for mt8183 cci devfreq
  devfreq: add mediatek cci devfreq
  cpufreq: mediatek: add opp notification for SVS support
  devfreq: cci devfreq register opp notification for SVS support

Stephen Boyd (1):
  PM / OPP: Support adjusting OPP voltages at runtime

 .../bindings/devfreq/mt8183-cci-devfreq.txt        |  20 ++
 drivers/cpufreq/cpufreq-dt-platdev.c               |   1 +
 drivers/cpufreq/mediatek-cpufreq.c                 |  88 +++++-
 drivers/devfreq/Kconfig                            |  10 +
 drivers/devfreq/Makefile                           |   1 +
 drivers/devfreq/mt8183-cci-devfreq.c               | 310 +++++++++++++++++++++
 drivers/opp/core.c                                 |  78 ++++++
 include/linux/pm_opp.h                             |  11 +
 8 files changed, 517 insertions(+), 2 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
 create mode 100644 drivers/devfreq/mt8183-cci-devfreq.c

-- 
2.12.5


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 1/8] cpufreq: mediatek: change to regulator_get_optional

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>

For new mediatek chip mt8183,
cci and little cluster share the same buck,
so need to modify the attribute of regulator from exclusive to optional

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>
---
 drivers/cpufreq/mediatek-cpufreq.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
index 48e9829274c6..f2464c1ff17c 100644
--- a/drivers/cpufreq/mediatek-cpufreq.c
+++ b/drivers/cpufreq/mediatek-cpufreq.c
@@ -346,7 +346,7 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
 		goto out_free_resources;
 	}
 
-	proc_reg = regulator_get_exclusive(cpu_dev, "proc");
+	proc_reg = regulator_get_optional(cpu_dev, "proc");
 	if (IS_ERR(proc_reg)) {
 		if (PTR_ERR(proc_reg) == -EPROBE_DEFER)
 			pr_warn("proc regulator for cpu%d not ready, retry.\n",
-- 
2.12.5

[PATCH 1/8] cpufreq: mediatek: change to regulator_get_optional

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>

For new mediatek chip mt8183,
cci and little cluster share the same buck,
so need to modify the attribute of regulator from exclusive to optional

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
---
 drivers/cpufreq/mediatek-cpufreq.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
index 48e9829274c6..f2464c1ff17c 100644
--- a/drivers/cpufreq/mediatek-cpufreq.c
+++ b/drivers/cpufreq/mediatek-cpufreq.c
@@ -346,7 +346,7 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
 		goto out_free_resources;
 	}
 
-	proc_reg = regulator_get_exclusive(cpu_dev, "proc");
+	proc_reg = regulator_get_optional(cpu_dev, "proc");
 	if (IS_ERR(proc_reg)) {
 		if (PTR_ERR(proc_reg) == -EPROBE_DEFER)
 			pr_warn("proc regulator for cpu%d not ready, retry.\n",
-- 
2.12.5


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 2/8] cpufreq: mediatek: add clock enable for intermediate clock

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>

Intermediate clock is not always enabled by ccf in different projects,
so cpufreq should always enable it by itself.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>
---
 drivers/cpufreq/mediatek-cpufreq.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
index f2464c1ff17c..b2fc01b17b57 100644
--- a/drivers/cpufreq/mediatek-cpufreq.c
+++ b/drivers/cpufreq/mediatek-cpufreq.c
@@ -376,13 +376,17 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
 		goto out_free_resources;
 	}
 
+	ret = clk_prepare_enable(inter_clk);
+	if (ret)
+		goto out_free_opp_table;
+
 	/* Search a safe voltage for intermediate frequency. */
 	rate = clk_get_rate(inter_clk);
 	opp = dev_pm_opp_find_freq_ceil(cpu_dev, &rate);
 	if (IS_ERR(opp)) {
 		pr_err("failed to get intermediate opp for cpu%d\n", cpu);
 		ret = PTR_ERR(opp);
-		goto out_free_opp_table;
+		goto out_disable_clock;
 	}
 	info->intermediate_voltage = dev_pm_opp_get_voltage(opp);
 	dev_pm_opp_put(opp);
@@ -401,6 +405,9 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
 
 	return 0;
 
+out_disable_clock:
+	clk_disable_unprepare(inter_clk);
+
 out_free_opp_table:
 	dev_pm_opp_of_cpumask_remove_table(&info->cpus);
 
@@ -427,6 +434,10 @@ static void mtk_cpu_dvfs_info_release(struct mtk_cpu_dvfs_info *info)
 		clk_put(info->cpu_clk);
 	if (!IS_ERR(info->inter_clk))
 		clk_put(info->inter_clk);
+	if (!IS_ERR(info->inter_clk)) {
+		clk_disable_unprepare(info->inter_clk);
+		clk_put(info->inter_clk);
+	}
 
 	dev_pm_opp_of_cpumask_remove_table(&info->cpus);
 }
-- 
2.12.5

[PATCH 2/8] cpufreq: mediatek: add clock enable for intermediate clock

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>

Intermediate clock is not always enabled by ccf in different projects,
so cpufreq should always enable it by itself.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
---
 drivers/cpufreq/mediatek-cpufreq.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
index f2464c1ff17c..b2fc01b17b57 100644
--- a/drivers/cpufreq/mediatek-cpufreq.c
+++ b/drivers/cpufreq/mediatek-cpufreq.c
@@ -376,13 +376,17 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
 		goto out_free_resources;
 	}
 
+	ret = clk_prepare_enable(inter_clk);
+	if (ret)
+		goto out_free_opp_table;
+
 	/* Search a safe voltage for intermediate frequency. */
 	rate = clk_get_rate(inter_clk);
 	opp = dev_pm_opp_find_freq_ceil(cpu_dev, &rate);
 	if (IS_ERR(opp)) {
 		pr_err("failed to get intermediate opp for cpu%d\n", cpu);
 		ret = PTR_ERR(opp);
-		goto out_free_opp_table;
+		goto out_disable_clock;
 	}
 	info->intermediate_voltage = dev_pm_opp_get_voltage(opp);
 	dev_pm_opp_put(opp);
@@ -401,6 +405,9 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
 
 	return 0;
 
+out_disable_clock:
+	clk_disable_unprepare(inter_clk);
+
 out_free_opp_table:
 	dev_pm_opp_of_cpumask_remove_table(&info->cpus);
 
@@ -427,6 +434,10 @@ static void mtk_cpu_dvfs_info_release(struct mtk_cpu_dvfs_info *info)
 		clk_put(info->cpu_clk);
 	if (!IS_ERR(info->inter_clk))
 		clk_put(info->inter_clk);
+	if (!IS_ERR(info->inter_clk)) {
+		clk_disable_unprepare(info->inter_clk);
+		clk_put(info->inter_clk);
+	}
 
 	dev_pm_opp_of_cpumask_remove_table(&info->cpus);
 }
-- 
2.12.5


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 3/8] cpufreq: mediatek: Add support for mt8183

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>

Add compatible string for mediatek mt8183

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>
---
 drivers/cpufreq/cpufreq-dt-platdev.c | 1 +
 drivers/cpufreq/mediatek-cpufreq.c   | 1 +
 2 files changed, 2 insertions(+)

diff --git a/drivers/cpufreq/cpufreq-dt-platdev.c b/drivers/cpufreq/cpufreq-dt-platdev.c
index 47729a22c159..53ea52b1602e 100644
--- a/drivers/cpufreq/cpufreq-dt-platdev.c
+++ b/drivers/cpufreq/cpufreq-dt-platdev.c
@@ -117,6 +117,7 @@ static const struct of_device_id blacklist[] __initconst = {
 	{ .compatible = "mediatek,mt817x", },
 	{ .compatible = "mediatek,mt8173", },
 	{ .compatible = "mediatek,mt8176", },
+	{ .compatible = "mediatek,mt8183", },
 
 	{ .compatible = "nvidia,tegra124", },
 	{ .compatible = "nvidia,tegra210", },
diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
index b2fc01b17b57..022d86757327 100644
--- a/drivers/cpufreq/mediatek-cpufreq.c
+++ b/drivers/cpufreq/mediatek-cpufreq.c
@@ -554,6 +554,7 @@ static const struct of_device_id mtk_cpufreq_machines[] __initconst = {
 	{ .compatible = "mediatek,mt817x", },
 	{ .compatible = "mediatek,mt8173", },
 	{ .compatible = "mediatek,mt8176", },
+	{ .compatible = "mediatek,mt8183", },
 
 	{ }
 };
-- 
2.12.5

[PATCH 3/8] cpufreq: mediatek: Add support for mt8183

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>

Add compatible string for mediatek mt8183

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
---
 drivers/cpufreq/cpufreq-dt-platdev.c | 1 +
 drivers/cpufreq/mediatek-cpufreq.c   | 1 +
 2 files changed, 2 insertions(+)

diff --git a/drivers/cpufreq/cpufreq-dt-platdev.c b/drivers/cpufreq/cpufreq-dt-platdev.c
index 47729a22c159..53ea52b1602e 100644
--- a/drivers/cpufreq/cpufreq-dt-platdev.c
+++ b/drivers/cpufreq/cpufreq-dt-platdev.c
@@ -117,6 +117,7 @@ static const struct of_device_id blacklist[] __initconst = {
 	{ .compatible = "mediatek,mt817x", },
 	{ .compatible = "mediatek,mt8173", },
 	{ .compatible = "mediatek,mt8176", },
+	{ .compatible = "mediatek,mt8183", },
 
 	{ .compatible = "nvidia,tegra124", },
 	{ .compatible = "nvidia,tegra210", },
diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
index b2fc01b17b57..022d86757327 100644
--- a/drivers/cpufreq/mediatek-cpufreq.c
+++ b/drivers/cpufreq/mediatek-cpufreq.c
@@ -554,6 +554,7 @@ static const struct of_device_id mtk_cpufreq_machines[] __initconst = {
 	{ .compatible = "mediatek,mt817x", },
 	{ .compatible = "mediatek,mt8173", },
 	{ .compatible = "mediatek,mt8176", },
+	{ .compatible = "mediatek,mt8183", },
 
 	{ }
 };
-- 
2.12.5


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 4/8] dt-bindings: devfreq: add compatible for mt8183 cci devfreq

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>

This adds dt-binding documentation of cci devfreq
for Mediatek MT8183 SoC platform.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>
---
 .../bindings/devfreq/mt8183-cci-devfreq.txt          | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt

diff --git a/Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt b/Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
new file mode 100644
index 000000000000..3189902902e0
--- /dev/null
+++ b/Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
@@ -0,0 +1,20 @@
+* Mediatek Cache Coherent Interconnect(CCI) frequency device
+
+Required properties:
+- compatible: should contain "mediatek,mt8183-cci" for frequency scaling of CCI
+- clocks: for frequency scaling of CCI
+- clock-names: for frequency scaling of CCI driver to reference
+- regulator: for voltage scaling of CCI
+- operating-points-v2: for frequency scaling of CCI opp table
+
+Example:
+	cci: cci {
+		compatible = "mediatek,cci";
+		clocks = <&apmixedsys CLK_APMIXED_CCIPLL>;
+		clock-names = "cci_clock";
+		operating-points-v2 = <&cci_opp>;
+	};
+
+	&cci {
+		proc-supply = <&mt6358_vproc12_reg>;
+	};
\ No newline at end of file
-- 
2.12.5

[PATCH 4/8] dt-bindings: devfreq: add compatible for mt8183 cci devfreq

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>

This adds dt-binding documentation of cci devfreq
for Mediatek MT8183 SoC platform.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
---
 .../bindings/devfreq/mt8183-cci-devfreq.txt          | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt

diff --git a/Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt b/Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
new file mode 100644
index 000000000000..3189902902e0
--- /dev/null
+++ b/Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
@@ -0,0 +1,20 @@
+* Mediatek Cache Coherent Interconnect(CCI) frequency device
+
+Required properties:
+- compatible: should contain "mediatek,mt8183-cci" for frequency scaling of CCI
+- clocks: for frequency scaling of CCI
+- clock-names: for frequency scaling of CCI driver to reference
+- regulator: for voltage scaling of CCI
+- operating-points-v2: for frequency scaling of CCI opp table
+
+Example:
+	cci: cci {
+		compatible = "mediatek,cci";
+		clocks = <&apmixedsys CLK_APMIXED_CCIPLL>;
+		clock-names = "cci_clock";
+		operating-points-v2 = <&cci_opp>;
+	};
+
+	&cci {
+		proc-supply = <&mt6358_vproc12_reg>;
+	};
\ No newline at end of file
-- 
2.12.5


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 5/8] devfreq: add mediatek cci devfreq

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>

This adds a devfreq driver for the Cache Coherent Interconnect (CCI)
of the Mediatek MT8183.

On the MT8183 the CCI is supplied by the same regulator as the LITTLE
cores. The driver is notified when the regulator voltage changes
(driven by cpufreq) and adjusts the CCI frequency to the maximum
possible value.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>
---
 drivers/devfreq/Kconfig              |  10 ++
 drivers/devfreq/Makefile             |   1 +
 drivers/devfreq/mt8183-cci-devfreq.c | 247 +++++++++++++++++++++++++++++++++++
 3 files changed, 258 insertions(+)
 create mode 100644 drivers/devfreq/mt8183-cci-devfreq.c

diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
index 6a172d338f6d..da2f8ec18369 100644
--- a/drivers/devfreq/Kconfig
+++ b/drivers/devfreq/Kconfig
@@ -91,6 +91,16 @@ config ARM_EXYNOS_BUS_DEVFREQ
 	  and adjusts the operating frequencies and voltages with OPP support.
 	  This does not yet operate with optimal voltages.
 
+config ARM_MT8183_CCI_DEVFREQ
+	tristate "MT8183 CCI DEVFREQ Driver"
+	depends on ARM_MEDIATEK_CPUFREQ
+	help
+		This adds a devfreq driver for Cache Coherent Interconnect
+		of Mediatek MT8183, which is shared the same regulator
+		with cpu cluster.
+		It can track buck voltage and update a proper cci frequency.
+		Use notification to get regulator status.
+
 config ARM_TEGRA_DEVFREQ
 	tristate "Tegra DEVFREQ Driver"
 	depends on ARCH_TEGRA_124_SOC
diff --git a/drivers/devfreq/Makefile b/drivers/devfreq/Makefile
index 32b8d4d3f12c..817dde779f16 100644
--- a/drivers/devfreq/Makefile
+++ b/drivers/devfreq/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_DEVFREQ_GOV_PASSIVE)	+= governor_passive.o
 
 # DEVFREQ Drivers
 obj-$(CONFIG_ARM_EXYNOS_BUS_DEVFREQ)	+= exynos-bus.o
+obj-$(CONFIG_ARM_MT8183_CCI_DEVFREQ)    += mt8183-cci-devfreq.o
 obj-$(CONFIG_ARM_RK3399_DMC_DEVFREQ)	+= rk3399_dmc.o
 obj-$(CONFIG_ARM_TEGRA_DEVFREQ)		+= tegra-devfreq.o
 
diff --git a/drivers/devfreq/mt8183-cci-devfreq.c b/drivers/devfreq/mt8183-cci-devfreq.c
new file mode 100644
index 000000000000..818a167c442f
--- /dev/null
+++ b/drivers/devfreq/mt8183-cci-devfreq.c
@@ -0,0 +1,247 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 MediaTek Inc.
+
+ * Author: Andrew-sh.Cheng <andrew-sh.cheng-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>
+ */
+
+#include <linux/clk.h>
+#include <linux/devfreq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+
+#include "governor.h"
+
+struct cci_devfreq {
+	struct devfreq *devfreq;
+	struct regulator *proc_reg;
+	unsigned long proc_reg_uV;
+	struct clk *cci_clk;
+	struct notifier_block nb;
+};
+
+static int cci_devfreq_regulator_notifier(struct notifier_block *nb,
+					  unsigned long val, void *data)
+{
+	int ret;
+	struct cci_devfreq *cci_df =
+		container_of(nb, struct cci_devfreq, nb);
+
+	/* deal with reduce frequency */
+	if (val & REGULATOR_EVENT_PRE_VOLTAGE_CHANGE) {
+		struct pre_voltage_change_data *pvc_data = data;
+
+		if (pvc_data->min_uV < pvc_data->old_uV) {
+			cci_df->proc_reg_uV =
+				(unsigned long)(pvc_data->min_uV);
+			mutex_lock(&cci_df->devfreq->lock);
+			ret = update_devfreq(cci_df->devfreq);
+			if (ret)
+				pr_err("Fail to reduce cci frequency: %d\n",
+				       ret);
+			mutex_unlock(&cci_df->devfreq->lock);
+		}
+	} else if ((val & REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE) &&
+	    ((unsigned long)data > cci_df->proc_reg_uV)) {
+		cci_df->proc_reg_uV = (unsigned long)data;
+		mutex_lock(&cci_df->devfreq->lock);
+		ret = update_devfreq(cci_df->devfreq);
+		if (ret)
+			pr_err("Fail to raise cci frequency back: %d\n", ret);
+		mutex_unlock(&cci_df->devfreq->lock);
+	} else if ((val & REGULATOR_EVENT_VOLTAGE_CHANGE) &&
+	    (cci_df->proc_reg_uV < (unsigned long)data)) {
+		/* deal with increase frequency */
+		cci_df->proc_reg_uV = (unsigned long)data;
+		mutex_lock(&cci_df->devfreq->lock);
+		ret = update_devfreq(cci_df->devfreq);
+		if (ret)
+			pr_err("Fail to raise cci frequency: %d\n", ret);
+		mutex_unlock(&cci_df->devfreq->lock);
+	}
+
+	return 0;
+}
+
+static int mtk_cci_governor_get_target(struct devfreq *devfreq,
+				       unsigned long *freq)
+{
+	struct cci_devfreq *cci_df;
+	struct dev_pm_opp *opp;
+
+	cci_df = dev_get_drvdata(devfreq->dev.parent);
+
+	/* find available frequency */
+	opp = dev_pm_opp_find_freq_ceil_by_volt(devfreq->dev.parent,
+						cci_df->proc_reg_uV);
+	*freq = dev_pm_opp_get_freq(opp);
+
+	return 0;
+}
+
+static int mtk_cci_governor_event_handler(struct devfreq *devfreq,
+					  unsigned int event, void *data)
+{
+	int ret;
+	struct cci_devfreq *cci_df;
+	struct notifier_block *nb;
+
+	cci_df = dev_get_drvdata(devfreq->dev.parent);
+	nb = &cci_df->nb;
+
+	switch (event) {
+	case DEVFREQ_GOV_START:
+	case DEVFREQ_GOV_RESUME:
+		nb->notifier_call = cci_devfreq_regulator_notifier;
+		ret = regulator_register_notifier(cci_df->proc_reg,
+						  nb);
+		if (ret)
+			pr_err("%s: failed to add governor: %d\n", __func__,
+			       ret);
+		break;
+
+	case DEVFREQ_GOV_STOP:
+	case DEVFREQ_GOV_SUSPEND:
+		ret = regulator_unregister_notifier(cci_df->proc_reg,
+						    nb);
+		if (ret)
+			pr_err("%s: failed to add governor: %d\n", __func__,
+			       ret);
+		break;
+
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static struct devfreq_governor mtk_cci_devfreq_governor = {
+	.name = "mtk_cci_vmon",
+	.get_target_freq = mtk_cci_governor_get_target,
+	.event_handler = mtk_cci_governor_event_handler,
+	.immutable = true
+};
+
+static int mtk_cci_devfreq_target(struct device *dev, unsigned long *freq,
+				  u32 flags)
+{
+	int ret;
+	struct cci_devfreq *cci_df = dev_get_drvdata(dev);
+
+	if (!cci_df)
+		return -EINVAL;
+
+	ret = clk_set_rate(cci_df->cci_clk, *freq);
+	if (ret) {
+		pr_err("%s: failed cci to set rate: %d\n", __func__,
+		       ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static struct devfreq_dev_profile cci_devfreq_profile = {
+	.target = mtk_cci_devfreq_target,
+};
+
+static int mtk_cci_devfreq_probe(struct platform_device *pdev)
+{
+	struct device *cci_dev = &pdev->dev;
+	struct cci_devfreq *cci_df;
+	int ret;
+
+	cci_df = devm_kzalloc(cci_dev, sizeof(*cci_df), GFP_KERNEL);
+	if (!cci_df)
+		return -ENOMEM;
+
+	cci_df->cci_clk = devm_clk_get(cci_dev, "cci_clock");
+	ret = PTR_ERR_OR_ZERO(cci_df->cci_clk);
+	if (ret) {
+		if (ret != -EPROBE_DEFER)
+			dev_err(cci_dev, "failed to get clock for CCI: %d\n",
+				ret);
+		return ret;
+	}
+	cci_df->proc_reg = devm_regulator_get_optional(cci_dev, "proc");
+	ret = PTR_ERR_OR_ZERO(cci_df->proc_reg);
+	if (ret) {
+		if (ret != -EPROBE_DEFER)
+			dev_err(cci_dev, "failed to get regulator for CCI: %d\n",
+				ret);
+		return ret;
+	}
+
+	ret = dev_pm_opp_of_add_table(cci_dev);
+	if (ret) {
+		dev_err(cci_dev, "Fail to init CCI OPP table: %d\n", ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, cci_df);
+
+	cci_df->devfreq = devm_devfreq_add_device(cci_dev,
+						  &cci_devfreq_profile,
+						  "mtk_cci_vmon",
+						  NULL);
+	if (IS_ERR(cci_df->devfreq)) {
+		ret = PTR_ERR(cci_df->devfreq);
+		dev_err(cci_dev, "cannot create cci devfreq device:%d\n", ret);
+		dev_pm_opp_of_remove_table(cci_dev);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const __maybe_unused struct of_device_id
+	mediatek_cci_devfreq_of_match[] = {
+	{ .compatible = "mediatek,mt8183-cci" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, mediatek_cci_devfreq_of_match);
+
+static struct platform_driver cci_devfreq_driver = {
+	.probe	= mtk_cci_devfreq_probe,
+	.driver = {
+		.name = "mediatek-cci-devfreq",
+		.of_match_table = of_match_ptr(mediatek_cci_devfreq_of_match),
+	},
+};
+
+static int __init mtk_cci_devfreq_init(void)
+{
+	int ret;
+
+	ret = devfreq_add_governor(&mtk_cci_devfreq_governor);
+	if (ret) {
+		pr_err("%s: failed to add governor: %d\n", __func__, ret);
+		return ret;
+	}
+
+	ret = platform_driver_register(&cci_devfreq_driver);
+	if (ret)
+		devfreq_remove_governor(&mtk_cci_devfreq_governor);
+
+	return ret;
+}
+module_init(mtk_cci_devfreq_init)
+
+static void __exit mtk_cci_devfreq_exit(void)
+{
+	int ret;
+
+	ret = devfreq_remove_governor(&mtk_cci_devfreq_governor);
+	if (ret)
+		pr_err("%s: failed to remove governor: %d\n", __func__, ret);
+
+	platform_driver_unregister(&cci_devfreq_driver);
+}
+module_exit(mtk_cci_devfreq_exit)
+
+MODULE_DESCRIPTION("Mediatek CCI devfreq driver");
+MODULE_AUTHOR("Andrew-sh.Cheng <andrew-sh.cheng-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>");
+MODULE_LICENSE("GPL v2");
-- 
2.12.5

[PATCH 5/8] devfreq: add mediatek cci devfreq

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>

This adds a devfreq driver for the Cache Coherent Interconnect (CCI)
of the Mediatek MT8183.

On the MT8183 the CCI is supplied by the same regulator as the LITTLE
cores. The driver is notified when the regulator voltage changes
(driven by cpufreq) and adjusts the CCI frequency to the maximum
possible value.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
---
 drivers/devfreq/Kconfig              |  10 ++
 drivers/devfreq/Makefile             |   1 +
 drivers/devfreq/mt8183-cci-devfreq.c | 247 +++++++++++++++++++++++++++++++++++
 3 files changed, 258 insertions(+)
 create mode 100644 drivers/devfreq/mt8183-cci-devfreq.c

diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
index 6a172d338f6d..da2f8ec18369 100644
--- a/drivers/devfreq/Kconfig
+++ b/drivers/devfreq/Kconfig
@@ -91,6 +91,16 @@ config ARM_EXYNOS_BUS_DEVFREQ
 	  and adjusts the operating frequencies and voltages with OPP support.
 	  This does not yet operate with optimal voltages.
 
+config ARM_MT8183_CCI_DEVFREQ
+	tristate "MT8183 CCI DEVFREQ Driver"
+	depends on ARM_MEDIATEK_CPUFREQ
+	help
+		This adds a devfreq driver for Cache Coherent Interconnect
+		of Mediatek MT8183, which is shared the same regulator
+		with cpu cluster.
+		It can track buck voltage and update a proper cci frequency.
+		Use notification to get regulator status.
+
 config ARM_TEGRA_DEVFREQ
 	tristate "Tegra DEVFREQ Driver"
 	depends on ARCH_TEGRA_124_SOC
diff --git a/drivers/devfreq/Makefile b/drivers/devfreq/Makefile
index 32b8d4d3f12c..817dde779f16 100644
--- a/drivers/devfreq/Makefile
+++ b/drivers/devfreq/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_DEVFREQ_GOV_PASSIVE)	+= governor_passive.o
 
 # DEVFREQ Drivers
 obj-$(CONFIG_ARM_EXYNOS_BUS_DEVFREQ)	+= exynos-bus.o
+obj-$(CONFIG_ARM_MT8183_CCI_DEVFREQ)    += mt8183-cci-devfreq.o
 obj-$(CONFIG_ARM_RK3399_DMC_DEVFREQ)	+= rk3399_dmc.o
 obj-$(CONFIG_ARM_TEGRA_DEVFREQ)		+= tegra-devfreq.o
 
diff --git a/drivers/devfreq/mt8183-cci-devfreq.c b/drivers/devfreq/mt8183-cci-devfreq.c
new file mode 100644
index 000000000000..818a167c442f
--- /dev/null
+++ b/drivers/devfreq/mt8183-cci-devfreq.c
@@ -0,0 +1,247 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 MediaTek Inc.
+
+ * Author: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/devfreq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+
+#include "governor.h"
+
+struct cci_devfreq {
+	struct devfreq *devfreq;
+	struct regulator *proc_reg;
+	unsigned long proc_reg_uV;
+	struct clk *cci_clk;
+	struct notifier_block nb;
+};
+
+static int cci_devfreq_regulator_notifier(struct notifier_block *nb,
+					  unsigned long val, void *data)
+{
+	int ret;
+	struct cci_devfreq *cci_df =
+		container_of(nb, struct cci_devfreq, nb);
+
+	/* deal with reduce frequency */
+	if (val & REGULATOR_EVENT_PRE_VOLTAGE_CHANGE) {
+		struct pre_voltage_change_data *pvc_data = data;
+
+		if (pvc_data->min_uV < pvc_data->old_uV) {
+			cci_df->proc_reg_uV =
+				(unsigned long)(pvc_data->min_uV);
+			mutex_lock(&cci_df->devfreq->lock);
+			ret = update_devfreq(cci_df->devfreq);
+			if (ret)
+				pr_err("Fail to reduce cci frequency: %d\n",
+				       ret);
+			mutex_unlock(&cci_df->devfreq->lock);
+		}
+	} else if ((val & REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE) &&
+	    ((unsigned long)data > cci_df->proc_reg_uV)) {
+		cci_df->proc_reg_uV = (unsigned long)data;
+		mutex_lock(&cci_df->devfreq->lock);
+		ret = update_devfreq(cci_df->devfreq);
+		if (ret)
+			pr_err("Fail to raise cci frequency back: %d\n", ret);
+		mutex_unlock(&cci_df->devfreq->lock);
+	} else if ((val & REGULATOR_EVENT_VOLTAGE_CHANGE) &&
+	    (cci_df->proc_reg_uV < (unsigned long)data)) {
+		/* deal with increase frequency */
+		cci_df->proc_reg_uV = (unsigned long)data;
+		mutex_lock(&cci_df->devfreq->lock);
+		ret = update_devfreq(cci_df->devfreq);
+		if (ret)
+			pr_err("Fail to raise cci frequency: %d\n", ret);
+		mutex_unlock(&cci_df->devfreq->lock);
+	}
+
+	return 0;
+}
+
+static int mtk_cci_governor_get_target(struct devfreq *devfreq,
+				       unsigned long *freq)
+{
+	struct cci_devfreq *cci_df;
+	struct dev_pm_opp *opp;
+
+	cci_df = dev_get_drvdata(devfreq->dev.parent);
+
+	/* find available frequency */
+	opp = dev_pm_opp_find_freq_ceil_by_volt(devfreq->dev.parent,
+						cci_df->proc_reg_uV);
+	*freq = dev_pm_opp_get_freq(opp);
+
+	return 0;
+}
+
+static int mtk_cci_governor_event_handler(struct devfreq *devfreq,
+					  unsigned int event, void *data)
+{
+	int ret;
+	struct cci_devfreq *cci_df;
+	struct notifier_block *nb;
+
+	cci_df = dev_get_drvdata(devfreq->dev.parent);
+	nb = &cci_df->nb;
+
+	switch (event) {
+	case DEVFREQ_GOV_START:
+	case DEVFREQ_GOV_RESUME:
+		nb->notifier_call = cci_devfreq_regulator_notifier;
+		ret = regulator_register_notifier(cci_df->proc_reg,
+						  nb);
+		if (ret)
+			pr_err("%s: failed to add governor: %d\n", __func__,
+			       ret);
+		break;
+
+	case DEVFREQ_GOV_STOP:
+	case DEVFREQ_GOV_SUSPEND:
+		ret = regulator_unregister_notifier(cci_df->proc_reg,
+						    nb);
+		if (ret)
+			pr_err("%s: failed to add governor: %d\n", __func__,
+			       ret);
+		break;
+
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static struct devfreq_governor mtk_cci_devfreq_governor = {
+	.name = "mtk_cci_vmon",
+	.get_target_freq = mtk_cci_governor_get_target,
+	.event_handler = mtk_cci_governor_event_handler,
+	.immutable = true
+};
+
+static int mtk_cci_devfreq_target(struct device *dev, unsigned long *freq,
+				  u32 flags)
+{
+	int ret;
+	struct cci_devfreq *cci_df = dev_get_drvdata(dev);
+
+	if (!cci_df)
+		return -EINVAL;
+
+	ret = clk_set_rate(cci_df->cci_clk, *freq);
+	if (ret) {
+		pr_err("%s: failed cci to set rate: %d\n", __func__,
+		       ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static struct devfreq_dev_profile cci_devfreq_profile = {
+	.target = mtk_cci_devfreq_target,
+};
+
+static int mtk_cci_devfreq_probe(struct platform_device *pdev)
+{
+	struct device *cci_dev = &pdev->dev;
+	struct cci_devfreq *cci_df;
+	int ret;
+
+	cci_df = devm_kzalloc(cci_dev, sizeof(*cci_df), GFP_KERNEL);
+	if (!cci_df)
+		return -ENOMEM;
+
+	cci_df->cci_clk = devm_clk_get(cci_dev, "cci_clock");
+	ret = PTR_ERR_OR_ZERO(cci_df->cci_clk);
+	if (ret) {
+		if (ret != -EPROBE_DEFER)
+			dev_err(cci_dev, "failed to get clock for CCI: %d\n",
+				ret);
+		return ret;
+	}
+	cci_df->proc_reg = devm_regulator_get_optional(cci_dev, "proc");
+	ret = PTR_ERR_OR_ZERO(cci_df->proc_reg);
+	if (ret) {
+		if (ret != -EPROBE_DEFER)
+			dev_err(cci_dev, "failed to get regulator for CCI: %d\n",
+				ret);
+		return ret;
+	}
+
+	ret = dev_pm_opp_of_add_table(cci_dev);
+	if (ret) {
+		dev_err(cci_dev, "Fail to init CCI OPP table: %d\n", ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, cci_df);
+
+	cci_df->devfreq = devm_devfreq_add_device(cci_dev,
+						  &cci_devfreq_profile,
+						  "mtk_cci_vmon",
+						  NULL);
+	if (IS_ERR(cci_df->devfreq)) {
+		ret = PTR_ERR(cci_df->devfreq);
+		dev_err(cci_dev, "cannot create cci devfreq device:%d\n", ret);
+		dev_pm_opp_of_remove_table(cci_dev);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const __maybe_unused struct of_device_id
+	mediatek_cci_devfreq_of_match[] = {
+	{ .compatible = "mediatek,mt8183-cci" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, mediatek_cci_devfreq_of_match);
+
+static struct platform_driver cci_devfreq_driver = {
+	.probe	= mtk_cci_devfreq_probe,
+	.driver = {
+		.name = "mediatek-cci-devfreq",
+		.of_match_table = of_match_ptr(mediatek_cci_devfreq_of_match),
+	},
+};
+
+static int __init mtk_cci_devfreq_init(void)
+{
+	int ret;
+
+	ret = devfreq_add_governor(&mtk_cci_devfreq_governor);
+	if (ret) {
+		pr_err("%s: failed to add governor: %d\n", __func__, ret);
+		return ret;
+	}
+
+	ret = platform_driver_register(&cci_devfreq_driver);
+	if (ret)
+		devfreq_remove_governor(&mtk_cci_devfreq_governor);
+
+	return ret;
+}
+module_init(mtk_cci_devfreq_init)
+
+static void __exit mtk_cci_devfreq_exit(void)
+{
+	int ret;
+
+	ret = devfreq_remove_governor(&mtk_cci_devfreq_governor);
+	if (ret)
+		pr_err("%s: failed to remove governor: %d\n", __func__, ret);
+
+	platform_driver_unregister(&cci_devfreq_driver);
+}
+module_exit(mtk_cci_devfreq_exit)
+
+MODULE_DESCRIPTION("Mediatek CCI devfreq driver");
+MODULE_AUTHOR("Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>");
+MODULE_LICENSE("GPL v2");
-- 
2.12.5


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 6/8] PM / OPP: Support adjusting OPP voltages at runtime

[Andrew-sh.Cheng]

From: Stephen Boyd <sboyd@codeaurora.org>

On some SoCs the Adaptive Voltage Scaling (AVS) technique is
employed to optimize the operating voltage of a device. At a
given frequency, the hardware monitors dynamic factors and either
makes a suggestion for how much to adjust a voltage for the
current frequency, or it automatically adjusts the voltage
without software intervention. Add an API to the OPP library for
the former case, so that AVS type devices can update the voltages
for an OPP when the hardware determines the voltage should
change. The assumption is that drivers like CPUfreq or devfreq
will register for the OPP notifiers and adjust the voltage
according to suggestions that AVS makes.

This patch is devired from [1] submitted by Stephen.
[1] https://lore.kernel.org/patchwork/patch/599279/

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Roger Lu <roger.lu@mediatek.com>
---
 drivers/opp/core.c     | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/pm_opp.h | 11 +++++++
 2 files changed, 89 insertions(+)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 0420f7e8ad5b..879ca5f50d1a 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -1946,6 +1946,84 @@ static int _opp_set_availability(struct device *dev, unsigned long freq,
 	return r;
 }
 
+/*
+ * dev_pm_opp_adjust_voltage() - helper to change the voltage of an OPP
+ * @dev:		device for which we do this operation
+ * @freq:		OPP frequency to adjust voltage of
+ * @u_volt:		new OPP voltage
+ *
+ * Change the voltage of an OPP with an RCU operation.
+ *
+ * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the
+ * copy operation, returns 0 if no modifcation was done OR modification was
+ * successful.
+ *
+ * Locking: The internal device_opp and opp structures are RCU protected.
+ * Hence this function internally uses RCU updater strategy with mutex locks to
+ * keep the integrity of the internal data structures. Callers should ensure
+ * that this function is *NOT* called under RCU protection or in contexts where
+ * mutex locking or synchronize_rcu() blocking calls cannot be used.
+ */
+int dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq,
+			      unsigned long u_volt)
+{
+	struct opp_table *opp_table;
+	struct dev_pm_opp *new_opp, *tmp_opp, *opp = ERR_PTR(-ENODEV);
+	int r = 0;
+
+	/* Find the opp_table */
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table)) {
+		r = PTR_ERR(opp_table);
+		dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r);
+		return r;
+	}
+
+	/* keep the node allocated */
+	new_opp = kmalloc(sizeof(*new_opp), GFP_KERNEL);
+	if (!new_opp)
+		return -ENOMEM;
+
+	mutex_lock(&opp_table->lock);
+
+	/* Do we have the frequency? */
+	list_for_each_entry(tmp_opp, &opp_table->opp_list, node) {
+		if (tmp_opp->rate == freq) {
+			opp = tmp_opp;
+			break;
+		}
+	}
+
+	if (IS_ERR(opp)) {
+		r = PTR_ERR(opp);
+		goto unlock;
+	}
+
+	/* Is update really needed? */
+	if (opp->supplies->u_volt == u_volt)
+		goto unlock;
+
+	/* copy the old data over */
+	*new_opp = *opp;
+
+	/* plug in new node */
+	new_opp->supplies->u_volt = u_volt;
+
+	list_replace_rcu(&opp->node, &new_opp->node);
+	mutex_unlock(&opp_table->lock);
+
+	/* Notify the change of the OPP */
+	blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADJUST_VOLTAGE,
+				     opp);
+
+	return 0;
+
+unlock:
+	mutex_unlock(&opp_table->lock);
+	kfree(new_opp);
+	return r;
+}
+
 /**
  * dev_pm_opp_enable() - Enable a specific OPP
  * @dev:	device for which we do this operation
diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h
index 24c757a32a7b..70219fe3ca20 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -25,6 +25,7 @@ struct opp_table;
 
 enum dev_pm_opp_event {
 	OPP_EVENT_ADD, OPP_EVENT_REMOVE, OPP_EVENT_ENABLE, OPP_EVENT_DISABLE,
+	OPP_EVENT_ADJUST_VOLTAGE,
 };
 
 /**
@@ -112,6 +113,9 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq,
 void dev_pm_opp_remove(struct device *dev, unsigned long freq);
 void dev_pm_opp_remove_all_dynamic(struct device *dev);
 
+int dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq,
+			      unsigned long u_volt);
+
 int dev_pm_opp_enable(struct device *dev, unsigned long freq);
 
 int dev_pm_opp_disable(struct device *dev, unsigned long freq);
@@ -229,6 +233,13 @@ static inline void dev_pm_opp_remove_all_dynamic(struct device *dev)
 {
 }
 
+static inline int
+dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq,
+			  unsigned long u_volt)
+{
+	return 0;
+}
+
 static inline int dev_pm_opp_enable(struct device *dev, unsigned long freq)
 {
 	return 0;
-- 
2.12.5

[PATCH 6/8] PM / OPP: Support adjusting OPP voltages at runtime

[Andrew-sh.Cheng]

From: Stephen Boyd <sboyd@codeaurora.org>

On some SoCs the Adaptive Voltage Scaling (AVS) technique is
employed to optimize the operating voltage of a device. At a
given frequency, the hardware monitors dynamic factors and either
makes a suggestion for how much to adjust a voltage for the
current frequency, or it automatically adjusts the voltage
without software intervention. Add an API to the OPP library for
the former case, so that AVS type devices can update the voltages
for an OPP when the hardware determines the voltage should
change. The assumption is that drivers like CPUfreq or devfreq
will register for the OPP notifiers and adjust the voltage
according to suggestions that AVS makes.

This patch is devired from [1] submitted by Stephen.
[1] https://lore.kernel.org/patchwork/patch/599279/

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Roger Lu <roger.lu@mediatek.com>
---
 drivers/opp/core.c     | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/pm_opp.h | 11 +++++++
 2 files changed, 89 insertions(+)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 0420f7e8ad5b..879ca5f50d1a 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -1946,6 +1946,84 @@ static int _opp_set_availability(struct device *dev, unsigned long freq,
 	return r;
 }
 
+/*
+ * dev_pm_opp_adjust_voltage() - helper to change the voltage of an OPP
+ * @dev:		device for which we do this operation
+ * @freq:		OPP frequency to adjust voltage of
+ * @u_volt:		new OPP voltage
+ *
+ * Change the voltage of an OPP with an RCU operation.
+ *
+ * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the
+ * copy operation, returns 0 if no modifcation was done OR modification was
+ * successful.
+ *
+ * Locking: The internal device_opp and opp structures are RCU protected.
+ * Hence this function internally uses RCU updater strategy with mutex locks to
+ * keep the integrity of the internal data structures. Callers should ensure
+ * that this function is *NOT* called under RCU protection or in contexts where
+ * mutex locking or synchronize_rcu() blocking calls cannot be used.
+ */
+int dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq,
+			      unsigned long u_volt)
+{
+	struct opp_table *opp_table;
+	struct dev_pm_opp *new_opp, *tmp_opp, *opp = ERR_PTR(-ENODEV);
+	int r = 0;
+
+	/* Find the opp_table */
+	opp_table = _find_opp_table(dev);
+	if (IS_ERR(opp_table)) {
+		r = PTR_ERR(opp_table);
+		dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r);
+		return r;
+	}
+
+	/* keep the node allocated */
+	new_opp = kmalloc(sizeof(*new_opp), GFP_KERNEL);
+	if (!new_opp)
+		return -ENOMEM;
+
+	mutex_lock(&opp_table->lock);
+
+	/* Do we have the frequency? */
+	list_for_each_entry(tmp_opp, &opp_table->opp_list, node) {
+		if (tmp_opp->rate == freq) {
+			opp = tmp_opp;
+			break;
+		}
+	}
+
+	if (IS_ERR(opp)) {
+		r = PTR_ERR(opp);
+		goto unlock;
+	}
+
+	/* Is update really needed? */
+	if (opp->supplies->u_volt == u_volt)
+		goto unlock;
+
+	/* copy the old data over */
+	*new_opp = *opp;
+
+	/* plug in new node */
+	new_opp->supplies->u_volt = u_volt;
+
+	list_replace_rcu(&opp->node, &new_opp->node);
+	mutex_unlock(&opp_table->lock);
+
+	/* Notify the change of the OPP */
+	blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADJUST_VOLTAGE,
+				     opp);
+
+	return 0;
+
+unlock:
+	mutex_unlock(&opp_table->lock);
+	kfree(new_opp);
+	return r;
+}
+
 /**
  * dev_pm_opp_enable() - Enable a specific OPP
  * @dev:	device for which we do this operation
diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h
index 24c757a32a7b..70219fe3ca20 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -25,6 +25,7 @@ struct opp_table;
 
 enum dev_pm_opp_event {
 	OPP_EVENT_ADD, OPP_EVENT_REMOVE, OPP_EVENT_ENABLE, OPP_EVENT_DISABLE,
+	OPP_EVENT_ADJUST_VOLTAGE,
 };
 
 /**
@@ -112,6 +113,9 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq,
 void dev_pm_opp_remove(struct device *dev, unsigned long freq);
 void dev_pm_opp_remove_all_dynamic(struct device *dev);
 
+int dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq,
+			      unsigned long u_volt);
+
 int dev_pm_opp_enable(struct device *dev, unsigned long freq);
 
 int dev_pm_opp_disable(struct device *dev, unsigned long freq);
@@ -229,6 +233,13 @@ static inline void dev_pm_opp_remove_all_dynamic(struct device *dev)
 {
 }
 
+static inline int
+dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq,
+			  unsigned long u_volt)
+{
+	return 0;
+}
+
 static inline int dev_pm_opp_enable(struct device *dev, unsigned long freq)
 {
 	return 0;
-- 
2.12.5


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 7/8] cpufreq: mediatek: add opp notification for SVS support

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>

cpufreq should listen opp notification and do proper actions
when receiving disable and voltage adjustment events,
which are triggered when SVS is enabled.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
---
 drivers/cpufreq/mediatek-cpufreq.c | 72 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 72 insertions(+)

diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
index 022d86757327..6514187a43f4 100644
--- a/drivers/cpufreq/mediatek-cpufreq.c
+++ b/drivers/cpufreq/mediatek-cpufreq.c
@@ -50,6 +50,10 @@ struct mtk_cpu_dvfs_info {
 	struct list_head list_head;
 	int intermediate_voltage;
 	bool need_voltage_tracking;
+	struct mutex lock; /* avoid notify and policy race condition */
+	struct notifier_block opp_nb;
+	int opp_cpu;
+	unsigned long opp_freq;
 };
 
 static LIST_HEAD(dvfs_info_list);
@@ -239,6 +243,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 	vproc = dev_pm_opp_get_voltage(opp);
 	dev_pm_opp_put(opp);
 
+	mutex_lock(&info->lock);
 	/*
 	 * If the new voltage or the intermediate voltage is higher than the
 	 * current voltage, scale up voltage first.
@@ -250,6 +255,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 			pr_err("cpu%d: failed to scale up voltage!\n",
 			       policy->cpu);
 			mtk_cpufreq_set_voltage(info, old_vproc);
+			mutex_unlock(&info->lock);
 			return ret;
 		}
 	}
@@ -261,6 +267,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 		       policy->cpu);
 		mtk_cpufreq_set_voltage(info, old_vproc);
 		WARN_ON(1);
+		mutex_unlock(&info->lock);
 		return ret;
 	}
 
@@ -271,6 +278,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 		       policy->cpu);
 		clk_set_parent(cpu_clk, armpll);
 		mtk_cpufreq_set_voltage(info, old_vproc);
+		mutex_unlock(&info->lock);
 		return ret;
 	}
 
@@ -281,6 +289,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 		       policy->cpu);
 		mtk_cpufreq_set_voltage(info, inter_vproc);
 		WARN_ON(1);
+		mutex_unlock(&info->lock);
 		return ret;
 	}
 
@@ -296,15 +305,69 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 			clk_set_parent(cpu_clk, info->inter_clk);
 			clk_set_rate(armpll, old_freq_hz);
 			clk_set_parent(cpu_clk, armpll);
+			mutex_unlock(&info->lock);
 			return ret;
 		}
 	}
 
+	info->opp_freq = freq_hz;
+	mutex_unlock(&info->lock);
+
 	return 0;
 }
 
 #define DYNAMIC_POWER "dynamic-power-coefficient"
 
+static int mtk_cpufreq_opp_notifier(struct notifier_block *nb,
+				    unsigned long event, void *data)
+{
+	struct dev_pm_opp *opp = data;
+	struct dev_pm_opp *opp_item;
+	struct mtk_cpu_dvfs_info *info =
+		container_of(nb, struct mtk_cpu_dvfs_info, opp_nb);
+	unsigned long freq, volt;
+	int ret = 0;
+
+	if (event == OPP_EVENT_ADJUST_VOLTAGE) {
+		freq = dev_pm_opp_get_freq(opp);
+
+		mutex_lock(&info->lock);
+		if (info->opp_freq == freq) {
+			volt = dev_pm_opp_get_voltage(opp);
+			ret = mtk_cpufreq_set_voltage(info, volt);
+			if (ret)
+				dev_err(info->cpu_dev, "failed to scale voltage: %d\n",
+					ret);
+		}
+		mutex_unlock(&info->lock);
+	} else if (event == OPP_EVENT_DISABLE) {
+		freq = info->opp_freq;
+		opp_item = dev_pm_opp_find_freq_ceil(info->cpu_dev, &freq);
+		if (!IS_ERR(opp_item))
+			dev_pm_opp_put(opp_item);
+		else
+			freq = 0;
+
+		/* case of current opp is disabled */
+		if (freq == 0 || freq != info->opp_freq) {
+			// find an enable opp item
+			freq = 1;
+			opp_item = dev_pm_opp_find_freq_ceil(info->cpu_dev,
+							     &freq);
+			if (!IS_ERR(opp_item)) {
+				dev_pm_opp_put(opp_item);
+				cpufreq_driver_target(
+					cpufreq_cpu_get(info->opp_cpu),
+					freq / 1000, CPUFREQ_RELATION_L);
+			} else
+				pr_err("%s: all opp items are disabled\n",
+				       __func__);
+		}
+	}
+
+	return notifier_from_errno(ret);
+}
+
 static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
 {
 	struct device *cpu_dev;
@@ -391,11 +454,20 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
 	info->intermediate_voltage = dev_pm_opp_get_voltage(opp);
 	dev_pm_opp_put(opp);
 
+	info->opp_cpu = cpu;
+	info->opp_nb.notifier_call = mtk_cpufreq_opp_notifier;
+	ret = dev_pm_opp_register_notifier(cpu_dev, &info->opp_nb);
+	if (ret) {
+		pr_warn("cannot register opp notification\n");
+		goto out_free_opp_table;
+	}
+
 	info->cpu_dev = cpu_dev;
 	info->proc_reg = proc_reg;
 	info->sram_reg = IS_ERR(sram_reg) ? NULL : sram_reg;
 	info->cpu_clk = cpu_clk;
 	info->inter_clk = inter_clk;
+	info->opp_freq = clk_get_rate(cpu_clk);
 
 	/*
 	 * If SRAM regulator is present, software "voltage tracking" is needed
-- 
2.12.5

[PATCH 7/8] cpufreq: mediatek: add opp notification for SVS support

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>

cpufreq should listen opp notification and do proper actions
when receiving disable and voltage adjustment events,
which are triggered when SVS is enabled.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
---
 drivers/cpufreq/mediatek-cpufreq.c | 72 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 72 insertions(+)

diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
index 022d86757327..6514187a43f4 100644
--- a/drivers/cpufreq/mediatek-cpufreq.c
+++ b/drivers/cpufreq/mediatek-cpufreq.c
@@ -50,6 +50,10 @@ struct mtk_cpu_dvfs_info {
 	struct list_head list_head;
 	int intermediate_voltage;
 	bool need_voltage_tracking;
+	struct mutex lock; /* avoid notify and policy race condition */
+	struct notifier_block opp_nb;
+	int opp_cpu;
+	unsigned long opp_freq;
 };
 
 static LIST_HEAD(dvfs_info_list);
@@ -239,6 +243,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 	vproc = dev_pm_opp_get_voltage(opp);
 	dev_pm_opp_put(opp);
 
+	mutex_lock(&info->lock);
 	/*
 	 * If the new voltage or the intermediate voltage is higher than the
 	 * current voltage, scale up voltage first.
@@ -250,6 +255,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 			pr_err("cpu%d: failed to scale up voltage!\n",
 			       policy->cpu);
 			mtk_cpufreq_set_voltage(info, old_vproc);
+			mutex_unlock(&info->lock);
 			return ret;
 		}
 	}
@@ -261,6 +267,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 		       policy->cpu);
 		mtk_cpufreq_set_voltage(info, old_vproc);
 		WARN_ON(1);
+		mutex_unlock(&info->lock);
 		return ret;
 	}
 
@@ -271,6 +278,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 		       policy->cpu);
 		clk_set_parent(cpu_clk, armpll);
 		mtk_cpufreq_set_voltage(info, old_vproc);
+		mutex_unlock(&info->lock);
 		return ret;
 	}
 
@@ -281,6 +289,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 		       policy->cpu);
 		mtk_cpufreq_set_voltage(info, inter_vproc);
 		WARN_ON(1);
+		mutex_unlock(&info->lock);
 		return ret;
 	}
 
@@ -296,15 +305,69 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 			clk_set_parent(cpu_clk, info->inter_clk);
 			clk_set_rate(armpll, old_freq_hz);
 			clk_set_parent(cpu_clk, armpll);
+			mutex_unlock(&info->lock);
 			return ret;
 		}
 	}
 
+	info->opp_freq = freq_hz;
+	mutex_unlock(&info->lock);
+
 	return 0;
 }
 
 #define DYNAMIC_POWER "dynamic-power-coefficient"
 
+static int mtk_cpufreq_opp_notifier(struct notifier_block *nb,
+				    unsigned long event, void *data)
+{
+	struct dev_pm_opp *opp = data;
+	struct dev_pm_opp *opp_item;
+	struct mtk_cpu_dvfs_info *info =
+		container_of(nb, struct mtk_cpu_dvfs_info, opp_nb);
+	unsigned long freq, volt;
+	int ret = 0;
+
+	if (event == OPP_EVENT_ADJUST_VOLTAGE) {
+		freq = dev_pm_opp_get_freq(opp);
+
+		mutex_lock(&info->lock);
+		if (info->opp_freq == freq) {
+			volt = dev_pm_opp_get_voltage(opp);
+			ret = mtk_cpufreq_set_voltage(info, volt);
+			if (ret)
+				dev_err(info->cpu_dev, "failed to scale voltage: %d\n",
+					ret);
+		}
+		mutex_unlock(&info->lock);
+	} else if (event == OPP_EVENT_DISABLE) {
+		freq = info->opp_freq;
+		opp_item = dev_pm_opp_find_freq_ceil(info->cpu_dev, &freq);
+		if (!IS_ERR(opp_item))
+			dev_pm_opp_put(opp_item);
+		else
+			freq = 0;
+
+		/* case of current opp is disabled */
+		if (freq == 0 || freq != info->opp_freq) {
+			// find an enable opp item
+			freq = 1;
+			opp_item = dev_pm_opp_find_freq_ceil(info->cpu_dev,
+							     &freq);
+			if (!IS_ERR(opp_item)) {
+				dev_pm_opp_put(opp_item);
+				cpufreq_driver_target(
+					cpufreq_cpu_get(info->opp_cpu),
+					freq / 1000, CPUFREQ_RELATION_L);
+			} else
+				pr_err("%s: all opp items are disabled\n",
+				       __func__);
+		}
+	}
+
+	return notifier_from_errno(ret);
+}
+
 static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
 {
 	struct device *cpu_dev;
@@ -391,11 +454,20 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
 	info->intermediate_voltage = dev_pm_opp_get_voltage(opp);
 	dev_pm_opp_put(opp);
 
+	info->opp_cpu = cpu;
+	info->opp_nb.notifier_call = mtk_cpufreq_opp_notifier;
+	ret = dev_pm_opp_register_notifier(cpu_dev, &info->opp_nb);
+	if (ret) {
+		pr_warn("cannot register opp notification\n");
+		goto out_free_opp_table;
+	}
+
 	info->cpu_dev = cpu_dev;
 	info->proc_reg = proc_reg;
 	info->sram_reg = IS_ERR(sram_reg) ? NULL : sram_reg;
 	info->cpu_clk = cpu_clk;
 	info->inter_clk = inter_clk;
+	info->opp_freq = clk_get_rate(cpu_clk);
 
 	/*
 	 * If SRAM regulator is present, software "voltage tracking" is needed
-- 
2.12.5


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 8/8] devfreq: mediatek: cci devfreq register opp notification for SVS support

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>

SVS will change the voltage of opp item.
CCI devfreq need to react to change frequency.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
---
 drivers/devfreq/mt8183-cci-devfreq.c | 63 ++++++++++++++++++++++++++++++++++++
 1 file changed, 63 insertions(+)

diff --git a/drivers/devfreq/mt8183-cci-devfreq.c b/drivers/devfreq/mt8183-cci-devfreq.c
index 818a167c442f..250c963789f3 100644
--- a/drivers/devfreq/mt8183-cci-devfreq.c
+++ b/drivers/devfreq/mt8183-cci-devfreq.c
@@ -19,7 +19,10 @@ struct cci_devfreq {
 	struct regulator *proc_reg;
 	unsigned long proc_reg_uV;
 	struct clk *cci_clk;
+	unsigned long freq;
 	struct notifier_block nb;
+	struct notifier_block opp_nb;
+	int cci_min_freq;
 };
 
 static int cci_devfreq_regulator_notifier(struct notifier_block *nb,
@@ -65,17 +68,62 @@ static int cci_devfreq_regulator_notifier(struct notifier_block *nb,
 	return 0;
 }
 
+static int ccidevfreq_opp_notifier(struct notifier_block *nb,
+unsigned long event, void *data)
+{
+	int ret;
+	struct dev_pm_opp *opp = data;
+	struct cci_devfreq *cci_df = container_of(nb, struct cci_devfreq,
+						  opp_nb);
+	unsigned long	freq, volt, cur_volt;
+
+	if (event == OPP_EVENT_ADJUST_VOLTAGE) {
+		freq = dev_pm_opp_get_freq(opp);
+		/* current opp item is changed */
+		if (freq == cci_df->freq) {
+			volt = dev_pm_opp_get_voltage(opp);
+			cur_volt = regulator_get_voltage(cci_df->proc_reg);
+
+			if (volt > cur_volt) {
+				/* need reduce freq */
+				mutex_lock(&cci_df->devfreq->lock);
+				ret = update_devfreq(cci_df->devfreq);
+				if (ret)
+					pr_err("Fail to reduce cci frequency by opp notification: %d\n",
+					       ret);
+				mutex_unlock(&cci_df->devfreq->lock);
+			}
+		}
+
+		if (freq == cci_df->cci_min_freq) {
+			volt = dev_pm_opp_get_voltage(opp);
+			regulator_set_voltage(cci_df->proc_reg, volt, INT_MAX);
+		}
+	} else if (event == OPP_EVENT_DISABLE) {
+	}
+
+	return 0;
+}
+
+
 static int mtk_cci_governor_get_target(struct devfreq *devfreq,
 				       unsigned long *freq)
 {
 	struct cci_devfreq *cci_df;
 	struct dev_pm_opp *opp;
+	int ret;
 
 	cci_df = dev_get_drvdata(devfreq->dev.parent);
 
 	/* find available frequency */
 	opp = dev_pm_opp_find_freq_ceil_by_volt(devfreq->dev.parent,
 						cci_df->proc_reg_uV);
+	ret = PTR_ERR_OR_ZERO(opp);
+	if (ret) {
+		pr_err("%s[%d], cannot find opp with voltage=%d: %d\n",
+		       __func__, __LINE__, cci_df->proc_reg_uV, ret);
+		return ret;
+	}
 	*freq = dev_pm_opp_get_freq(opp);
 
 	return 0;
@@ -87,9 +135,11 @@ static int mtk_cci_governor_event_handler(struct devfreq *devfreq,
 	int ret;
 	struct cci_devfreq *cci_df;
 	struct notifier_block *nb;
+	struct notifier_block *opp_nb;
 
 	cci_df = dev_get_drvdata(devfreq->dev.parent);
 	nb = &cci_df->nb;
+	opp_nb = &cci_df->opp_nb;
 
 	switch (event) {
 	case DEVFREQ_GOV_START:
@@ -100,6 +150,8 @@ static int mtk_cci_governor_event_handler(struct devfreq *devfreq,
 		if (ret)
 			pr_err("%s: failed to add governor: %d\n", __func__,
 			       ret);
+		opp_nb->notifier_call = ccidevfreq_opp_notifier;
+		dev_pm_opp_register_notifier(devfreq->dev.parent, opp_nb);
 		break;
 
 	case DEVFREQ_GOV_STOP:
@@ -141,6 +193,8 @@ static int mtk_cci_devfreq_target(struct device *dev, unsigned long *freq,
 		return ret;
 	}
 
+	cci_df->freq = *freq;
+
 	return 0;
 }
 
@@ -152,6 +206,8 @@ static int mtk_cci_devfreq_probe(struct platform_device *pdev)
 {
 	struct device *cci_dev = &pdev->dev;
 	struct cci_devfreq *cci_df;
+	unsigned long freq, volt;
+	struct dev_pm_opp *opp;
 	int ret;
 
 	cci_df = devm_kzalloc(cci_dev, sizeof(*cci_df), GFP_KERNEL);
@@ -181,6 +237,13 @@ static int mtk_cci_devfreq_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	/* set voltage lower bound */
+	freq = 1;
+	opp = dev_pm_opp_find_freq_ceil(cci_dev, &freq);
+	cci_df->cci_min_freq = dev_pm_opp_get_freq(opp);
+	volt = dev_pm_opp_get_voltage(opp);
+	dev_pm_opp_put(opp);
+
 	platform_set_drvdata(pdev, cci_df);
 
 	cci_df->devfreq = devm_devfreq_add_device(cci_dev,
-- 
2.12.5

[PATCH 8/8] devfreq: mediatek: cci devfreq register opp notification for SVS support

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>

SVS will change the voltage of opp item.
CCI devfreq need to react to change frequency.

Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
---
 drivers/devfreq/mt8183-cci-devfreq.c | 63 ++++++++++++++++++++++++++++++++++++
 1 file changed, 63 insertions(+)

diff --git a/drivers/devfreq/mt8183-cci-devfreq.c b/drivers/devfreq/mt8183-cci-devfreq.c
index 818a167c442f..250c963789f3 100644
--- a/drivers/devfreq/mt8183-cci-devfreq.c
+++ b/drivers/devfreq/mt8183-cci-devfreq.c
@@ -19,7 +19,10 @@ struct cci_devfreq {
 	struct regulator *proc_reg;
 	unsigned long proc_reg_uV;
 	struct clk *cci_clk;
+	unsigned long freq;
 	struct notifier_block nb;
+	struct notifier_block opp_nb;
+	int cci_min_freq;
 };
 
 static int cci_devfreq_regulator_notifier(struct notifier_block *nb,
@@ -65,17 +68,62 @@ static int cci_devfreq_regulator_notifier(struct notifier_block *nb,
 	return 0;
 }
 
+static int ccidevfreq_opp_notifier(struct notifier_block *nb,
+unsigned long event, void *data)
+{
+	int ret;
+	struct dev_pm_opp *opp = data;
+	struct cci_devfreq *cci_df = container_of(nb, struct cci_devfreq,
+						  opp_nb);
+	unsigned long	freq, volt, cur_volt;
+
+	if (event == OPP_EVENT_ADJUST_VOLTAGE) {
+		freq = dev_pm_opp_get_freq(opp);
+		/* current opp item is changed */
+		if (freq == cci_df->freq) {
+			volt = dev_pm_opp_get_voltage(opp);
+			cur_volt = regulator_get_voltage(cci_df->proc_reg);
+
+			if (volt > cur_volt) {
+				/* need reduce freq */
+				mutex_lock(&cci_df->devfreq->lock);
+				ret = update_devfreq(cci_df->devfreq);
+				if (ret)
+					pr_err("Fail to reduce cci frequency by opp notification: %d\n",
+					       ret);
+				mutex_unlock(&cci_df->devfreq->lock);
+			}
+		}
+
+		if (freq == cci_df->cci_min_freq) {
+			volt = dev_pm_opp_get_voltage(opp);
+			regulator_set_voltage(cci_df->proc_reg, volt, INT_MAX);
+		}
+	} else if (event == OPP_EVENT_DISABLE) {
+	}
+
+	return 0;
+}
+
+
 static int mtk_cci_governor_get_target(struct devfreq *devfreq,
 				       unsigned long *freq)
 {
 	struct cci_devfreq *cci_df;
 	struct dev_pm_opp *opp;
+	int ret;
 
 	cci_df = dev_get_drvdata(devfreq->dev.parent);
 
 	/* find available frequency */
 	opp = dev_pm_opp_find_freq_ceil_by_volt(devfreq->dev.parent,
 						cci_df->proc_reg_uV);
+	ret = PTR_ERR_OR_ZERO(opp);
+	if (ret) {
+		pr_err("%s[%d], cannot find opp with voltage=%d: %d\n",
+		       __func__, __LINE__, cci_df->proc_reg_uV, ret);
+		return ret;
+	}
 	*freq = dev_pm_opp_get_freq(opp);
 
 	return 0;
@@ -87,9 +135,11 @@ static int mtk_cci_governor_event_handler(struct devfreq *devfreq,
 	int ret;
 	struct cci_devfreq *cci_df;
 	struct notifier_block *nb;
+	struct notifier_block *opp_nb;
 
 	cci_df = dev_get_drvdata(devfreq->dev.parent);
 	nb = &cci_df->nb;
+	opp_nb = &cci_df->opp_nb;
 
 	switch (event) {
 	case DEVFREQ_GOV_START:
@@ -100,6 +150,8 @@ static int mtk_cci_governor_event_handler(struct devfreq *devfreq,
 		if (ret)
 			pr_err("%s: failed to add governor: %d\n", __func__,
 			       ret);
+		opp_nb->notifier_call = ccidevfreq_opp_notifier;
+		dev_pm_opp_register_notifier(devfreq->dev.parent, opp_nb);
 		break;
 
 	case DEVFREQ_GOV_STOP:
@@ -141,6 +193,8 @@ static int mtk_cci_devfreq_target(struct device *dev, unsigned long *freq,
 		return ret;
 	}
 
+	cci_df->freq = *freq;
+
 	return 0;
 }
 
@@ -152,6 +206,8 @@ static int mtk_cci_devfreq_probe(struct platform_device *pdev)
 {
 	struct device *cci_dev = &pdev->dev;
 	struct cci_devfreq *cci_df;
+	unsigned long freq, volt;
+	struct dev_pm_opp *opp;
 	int ret;
 
 	cci_df = devm_kzalloc(cci_dev, sizeof(*cci_df), GFP_KERNEL);
@@ -181,6 +237,13 @@ static int mtk_cci_devfreq_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	/* set voltage lower bound */
+	freq = 1;
+	opp = dev_pm_opp_find_freq_ceil(cci_dev, &freq);
+	cci_df->cci_min_freq = dev_pm_opp_get_freq(opp);
+	volt = dev_pm_opp_get_voltage(opp);
+	dev_pm_opp_put(opp);
+
 	platform_set_drvdata(pdev, cci_df);
 
 	cci_df->devfreq = devm_devfreq_add_device(cci_dev,
-- 
2.12.5


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH 0/8] Add cpufreq and cci devfreq for mt8183, and SVS support

[Viresh Kumar]

On 16-05-19, 17:08, Andrew-sh.Cheng wrote:
> From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>
> 
> MT8183 supports CPU DVFS and CCI DVFS, and LITTLE cpus and CCI are in the same voltage domain.
> So, this series is to add drivers to handle the voltage coupling between CPU and CCI DVFS.
> 
> For SVS support, add OPP_EVENT_ADJUST_VOLTAGE and corresponding reaction.

No version information here or what has changed. That doesn't help.

I believe this is V3.

Don't resend it but please mention the changes in reply now. Thanks.

> Andrew-sh.Cheng (7):
>   cpufreq: mediatek: change to regulator_get_optional
>   cpufreq: mediatek: add clock enable for intermediate clock
>   cpufreq: mediatek: Add support for mt8183
>   dt-bindings: devfreq: add compatible for mt8183 cci devfreq
>   devfreq: add mediatek cci devfreq
>   cpufreq: mediatek: add opp notification for SVS support
>   devfreq: cci devfreq register opp notification for SVS support
> 
> Stephen Boyd (1):
>   PM / OPP: Support adjusting OPP voltages at runtime
> 
>  .../bindings/devfreq/mt8183-cci-devfreq.txt        |  20 ++
>  drivers/cpufreq/cpufreq-dt-platdev.c               |   1 +
>  drivers/cpufreq/mediatek-cpufreq.c                 |  88 +++++-
>  drivers/devfreq/Kconfig                            |  10 +
>  drivers/devfreq/Makefile                           |   1 +
>  drivers/devfreq/mt8183-cci-devfreq.c               | 310 +++++++++++++++++++++
>  drivers/opp/core.c                                 |  78 ++++++
>  include/linux/pm_opp.h                             |  11 +
>  8 files changed, 517 insertions(+), 2 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
>  create mode 100644 drivers/devfreq/mt8183-cci-devfreq.c
> 
> -- 
> 2.12.5

-- 
viresh

Re: [PATCH 0/8] Add cpufreq and cci devfreq for mt8183, and SVS support

[Viresh Kumar]

On 16-05-19, 17:08, Andrew-sh.Cheng wrote:
> From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>
> 
> MT8183 supports CPU DVFS and CCI DVFS, and LITTLE cpus and CCI are in the same voltage domain.
> So, this series is to add drivers to handle the voltage coupling between CPU and CCI DVFS.
> 
> For SVS support, add OPP_EVENT_ADJUST_VOLTAGE and corresponding reaction.

No version information here or what has changed. That doesn't help.

I believe this is V3.

Don't resend it but please mention the changes in reply now. Thanks.

> Andrew-sh.Cheng (7):
>   cpufreq: mediatek: change to regulator_get_optional
>   cpufreq: mediatek: add clock enable for intermediate clock
>   cpufreq: mediatek: Add support for mt8183
>   dt-bindings: devfreq: add compatible for mt8183 cci devfreq
>   devfreq: add mediatek cci devfreq
>   cpufreq: mediatek: add opp notification for SVS support
>   devfreq: cci devfreq register opp notification for SVS support
> 
> Stephen Boyd (1):
>   PM / OPP: Support adjusting OPP voltages at runtime
> 
>  .../bindings/devfreq/mt8183-cci-devfreq.txt        |  20 ++
>  drivers/cpufreq/cpufreq-dt-platdev.c               |   1 +
>  drivers/cpufreq/mediatek-cpufreq.c                 |  88 +++++-
>  drivers/devfreq/Kconfig                            |  10 +
>  drivers/devfreq/Makefile                           |   1 +
>  drivers/devfreq/mt8183-cci-devfreq.c               | 310 +++++++++++++++++++++
>  drivers/opp/core.c                                 |  78 ++++++
>  include/linux/pm_opp.h                             |  11 +
>  8 files changed, 517 insertions(+), 2 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
>  create mode 100644 drivers/devfreq/mt8183-cci-devfreq.c
> 
> -- 
> 2.12.5

-- 
viresh

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH 0/8] Add cpufreq and cci devfreq for mt8183, and SVS support

[andrew-sh.cheng]

On Thu, 2019-05-16 at 14:53 +0530, Viresh Kumar wrote:
> On 16-05-19, 17:08, Andrew-sh.Cheng wrote:
> > From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>
> > 
> > MT8183 supports CPU DVFS and CCI DVFS, and LITTLE cpus and CCI are in the same voltage domain.
> > So, this series is to add drivers to handle the voltage coupling between CPU and CCI DVFS.
> > 
> > For SVS support, add OPP_EVENT_ADJUST_VOLTAGE and corresponding reaction.
> 
> No version information here or what has changed. That doesn't help.
> 
> I believe this is V3.
> 
> Don't resend it but please mention the changes in reply now. Thanks.
Yes, this is patch v3

Change since v2:
- Separate cpufreq modification into 3 patches.
- Modify dt-binding for more HW information.
- Refine cci devfreq coding style.
- patch 6 ~ patch 8 are for SVS support

> 
> > Andrew-sh.Cheng (7):
> >   cpufreq: mediatek: change to regulator_get_optional
> >   cpufreq: mediatek: add clock enable for intermediate clock
> >   cpufreq: mediatek: Add support for mt8183
> >   dt-bindings: devfreq: add compatible for mt8183 cci devfreq
> >   devfreq: add mediatek cci devfreq
> >   cpufreq: mediatek: add opp notification for SVS support
> >   devfreq: cci devfreq register opp notification for SVS support
> > 
> > Stephen Boyd (1):
> >   PM / OPP: Support adjusting OPP voltages at runtime
> > 
> >  .../bindings/devfreq/mt8183-cci-devfreq.txt        |  20 ++
> >  drivers/cpufreq/cpufreq-dt-platdev.c               |   1 +
> >  drivers/cpufreq/mediatek-cpufreq.c                 |  88 +++++-
> >  drivers/devfreq/Kconfig                            |  10 +
> >  drivers/devfreq/Makefile                           |   1 +
> >  drivers/devfreq/mt8183-cci-devfreq.c               | 310 +++++++++++++++++++++
> >  drivers/opp/core.c                                 |  78 ++++++
> >  include/linux/pm_opp.h                             |  11 +
> >  8 files changed, 517 insertions(+), 2 deletions(-)
> >  create mode 100644 Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
> >  create mode 100644 drivers/devfreq/mt8183-cci-devfreq.c
> > 
> > -- 
> > 2.12.5
> 

Re: [PATCH 0/8] Add cpufreq and cci devfreq for mt8183, and SVS support

[andrew-sh.cheng]

On Thu, 2019-05-16 at 14:53 +0530, Viresh Kumar wrote:
> On 16-05-19, 17:08, Andrew-sh.Cheng wrote:
> > From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>
> > 
> > MT8183 supports CPU DVFS and CCI DVFS, and LITTLE cpus and CCI are in the same voltage domain.
> > So, this series is to add drivers to handle the voltage coupling between CPU and CCI DVFS.
> > 
> > For SVS support, add OPP_EVENT_ADJUST_VOLTAGE and corresponding reaction.
> 
> No version information here or what has changed. That doesn't help.
> 
> I believe this is V3.
> 
> Don't resend it but please mention the changes in reply now. Thanks.
Yes, this is patch v3

Change since v2:
- Separate cpufreq modification into 3 patches.
- Modify dt-binding for more HW information.
- Refine cci devfreq coding style.
- patch 6 ~ patch 8 are for SVS support

> 
> > Andrew-sh.Cheng (7):
> >   cpufreq: mediatek: change to regulator_get_optional
> >   cpufreq: mediatek: add clock enable for intermediate clock
> >   cpufreq: mediatek: Add support for mt8183
> >   dt-bindings: devfreq: add compatible for mt8183 cci devfreq
> >   devfreq: add mediatek cci devfreq
> >   cpufreq: mediatek: add opp notification for SVS support
> >   devfreq: cci devfreq register opp notification for SVS support
> > 
> > Stephen Boyd (1):
> >   PM / OPP: Support adjusting OPP voltages at runtime
> > 
> >  .../bindings/devfreq/mt8183-cci-devfreq.txt        |  20 ++
> >  drivers/cpufreq/cpufreq-dt-platdev.c               |   1 +
> >  drivers/cpufreq/mediatek-cpufreq.c                 |  88 +++++-
> >  drivers/devfreq/Kconfig                            |  10 +
> >  drivers/devfreq/Makefile                           |   1 +
> >  drivers/devfreq/mt8183-cci-devfreq.c               | 310 +++++++++++++++++++++
> >  drivers/opp/core.c                                 |  78 ++++++
> >  include/linux/pm_opp.h                             |  11 +
> >  8 files changed, 517 insertions(+), 2 deletions(-)
> >  create mode 100644 Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
> >  create mode 100644 drivers/devfreq/mt8183-cci-devfreq.c
> > 
> > -- 
> > 2.12.5
> 



_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH 4/8] dt-bindings: devfreq: add compatible for mt8183 cci devfreq

[Viresh Kumar]

On 16-05-19, 17:08, Andrew-sh.Cheng wrote:
> From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>
> 
> This adds dt-binding documentation of cci devfreq
> for Mediatek MT8183 SoC platform.
> 
> Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
> ---
>  .../bindings/devfreq/mt8183-cci-devfreq.txt          | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
> 
> diff --git a/Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt b/Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
> new file mode 100644
> index 000000000000..3189902902e0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
> @@ -0,0 +1,20 @@
> +* Mediatek Cache Coherent Interconnect(CCI) frequency device
> +
> +Required properties:
> +- compatible: should contain "mediatek,mt8183-cci" for frequency scaling of CCI

Example doesn't have this compatible .

> +- clocks: for frequency scaling of CCI
> +- clock-names: for frequency scaling of CCI driver to reference
> +- regulator: for voltage scaling of CCI
> +- operating-points-v2: for frequency scaling of CCI opp table
> +
> +Example:
> +	cci: cci {
> +		compatible = "mediatek,cci";
> +		clocks = <&apmixedsys CLK_APMIXED_CCIPLL>;
> +		clock-names = "cci_clock";
> +		operating-points-v2 = <&cci_opp>;
> +	};
> +
> +	&cci {
> +		proc-supply = <&mt6358_vproc12_reg>;
> +	};
> \ No newline at end of file
> -- 
> 2.12.5

-- 
viresh

Re: [PATCH 4/8] dt-bindings: devfreq: add compatible for mt8183 cci devfreq

[Viresh Kumar]

On 16-05-19, 17:08, Andrew-sh.Cheng wrote:
> From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>
> 
> This adds dt-binding documentation of cci devfreq
> for Mediatek MT8183 SoC platform.
> 
> Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
> ---
>  .../bindings/devfreq/mt8183-cci-devfreq.txt          | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
> 
> diff --git a/Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt b/Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
> new file mode 100644
> index 000000000000..3189902902e0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/devfreq/mt8183-cci-devfreq.txt
> @@ -0,0 +1,20 @@
> +* Mediatek Cache Coherent Interconnect(CCI) frequency device
> +
> +Required properties:
> +- compatible: should contain "mediatek,mt8183-cci" for frequency scaling of CCI

Example doesn't have this compatible .

> +- clocks: for frequency scaling of CCI
> +- clock-names: for frequency scaling of CCI driver to reference
> +- regulator: for voltage scaling of CCI
> +- operating-points-v2: for frequency scaling of CCI opp table
> +
> +Example:
> +	cci: cci {
> +		compatible = "mediatek,cci";
> +		clocks = <&apmixedsys CLK_APMIXED_CCIPLL>;
> +		clock-names = "cci_clock";
> +		operating-points-v2 = <&cci_opp>;
> +	};
> +
> +	&cci {
> +		proc-supply = <&mt6358_vproc12_reg>;
> +	};
> \ No newline at end of file
> -- 
> 2.12.5

-- 
viresh

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH 6/8] PM / OPP: Support adjusting OPP voltages at runtime

[Viresh Kumar]

On 16-05-19, 17:08, Andrew-sh.Cheng wrote:
> From: Stephen Boyd <sboyd@codeaurora.org>
> 
> On some SoCs the Adaptive Voltage Scaling (AVS) technique is
> employed to optimize the operating voltage of a device. At a
> given frequency, the hardware monitors dynamic factors and either
> makes a suggestion for how much to adjust a voltage for the
> current frequency, or it automatically adjusts the voltage
> without software intervention. Add an API to the OPP library for
> the former case, so that AVS type devices can update the voltages
> for an OPP when the hardware determines the voltage should
> change. The assumption is that drivers like CPUfreq or devfreq
> will register for the OPP notifiers and adjust the voltage
> according to suggestions that AVS makes.
> 
> This patch is devired from [1] submitted by Stephen.
> [1] https://lore.kernel.org/patchwork/patch/599279/
> 
> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
> Signed-off-by: Roger Lu <roger.lu@mediatek.com>
> ---
>  drivers/opp/core.c     | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/pm_opp.h | 11 +++++++
>  2 files changed, 89 insertions(+)

This is an rcu implementation which got removed long back from OPP core. Please
align this with the latest changes.

-- 
viresh

Re: [PATCH 6/8] PM / OPP: Support adjusting OPP voltages at runtime

[Viresh Kumar]

On 16-05-19, 17:08, Andrew-sh.Cheng wrote:
> From: Stephen Boyd <sboyd@codeaurora.org>
> 
> On some SoCs the Adaptive Voltage Scaling (AVS) technique is
> employed to optimize the operating voltage of a device. At a
> given frequency, the hardware monitors dynamic factors and either
> makes a suggestion for how much to adjust a voltage for the
> current frequency, or it automatically adjusts the voltage
> without software intervention. Add an API to the OPP library for
> the former case, so that AVS type devices can update the voltages
> for an OPP when the hardware determines the voltage should
> change. The assumption is that drivers like CPUfreq or devfreq
> will register for the OPP notifiers and adjust the voltage
> according to suggestions that AVS makes.
> 
> This patch is devired from [1] submitted by Stephen.
> [1] https://lore.kernel.org/patchwork/patch/599279/
> 
> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
> Signed-off-by: Roger Lu <roger.lu@mediatek.com>
> ---
>  drivers/opp/core.c     | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/pm_opp.h | 11 +++++++
>  2 files changed, 89 insertions(+)

This is an rcu implementation which got removed long back from OPP core. Please
align this with the latest changes.

-- 
viresh

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH 8/8] devfreq: mediatek: cci devfreq register opp notification for SVS support

[Hsin-Yi Wang]

On Thu, May 16, 2019 at 9:08 AM Andrew-sh.Cheng
<andrew-sh.cheng@mediatek.com> wrote:
>
> From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>
>
> SVS will change the voltage of opp item.
> CCI devfreq need to react to change frequency.
>
> Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
> ---
>  drivers/devfreq/mt8183-cci-devfreq.c | 63 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 63 insertions(+)
>
> diff --git a/drivers/devfreq/mt8183-cci-devfreq.c b/drivers/devfreq/mt8183-cci-devfreq.c
> index 818a167c442f..250c963789f3 100644
> --- a/drivers/devfreq/mt8183-cci-devfreq.c
> +++ b/drivers/devfreq/mt8183-cci-devfreq.c
> @@ -19,7 +19,10 @@ struct cci_devfreq {
>         struct regulator *proc_reg;
>         unsigned long proc_reg_uV;
>         struct clk *cci_clk;
> +       unsigned long freq;
>         struct notifier_block nb;
> +       struct notifier_block opp_nb;
> +       int cci_min_freq;
>  };
>
>  static int cci_devfreq_regulator_notifier(struct notifier_block *nb,
> @@ -65,17 +68,62 @@ static int cci_devfreq_regulator_notifier(struct notifier_block *nb,
>         return 0;
>  }
>
> +static int ccidevfreq_opp_notifier(struct notifier_block *nb,
> +unsigned long event, void *data)
> +{
> +       int ret;
> +       struct dev_pm_opp *opp = data;
> +       struct cci_devfreq *cci_df = container_of(nb, struct cci_devfreq,
> +                                                 opp_nb);
> +       unsigned long   freq, volt, cur_volt;
> +
> +       if (event == OPP_EVENT_ADJUST_VOLTAGE) {
> +               freq = dev_pm_opp_get_freq(opp);
> +               /* current opp item is changed */
> +               if (freq == cci_df->freq) {
> +                       volt = dev_pm_opp_get_voltage(opp);
> +                       cur_volt = regulator_get_voltage(cci_df->proc_reg);
> +
> +                       if (volt > cur_volt) {
> +                               /* need reduce freq */
> +                               mutex_lock(&cci_df->devfreq->lock);
> +                               ret = update_devfreq(cci_df->devfreq);
> +                               if (ret)
> +                                       pr_err("Fail to reduce cci frequency by opp notification: %d\n",
This line is too long
> +                                              ret);
> +                               mutex_unlock(&cci_df->devfreq->lock);
> +                       }
> +               }
> +
> +               if (freq == cci_df->cci_min_freq) {
> +                       volt = dev_pm_opp_get_voltage(opp);
> +                       regulator_set_voltage(cci_df->proc_reg, volt, INT_MAX);
> +               }
> +       } else if (event == OPP_EVENT_DISABLE) {
Is this case handled? If not, is this branch needed?
> +       }
> +
> +       return 0;
> +}
> +
> +
>  static int mtk_cci_governor_get_target(struct devfreq *devfreq,
>                                        unsigned long *freq)
>  {
>         struct cci_devfreq *cci_df;
>         struct dev_pm_opp *opp;
> +       int ret;
>
>         cci_df = dev_get_drvdata(devfreq->dev.parent);
>
>         /* find available frequency */
>         opp = dev_pm_opp_find_freq_ceil_by_volt(devfreq->dev.parent,
>                                                 cci_df->proc_reg_uV);
> +       ret = PTR_ERR_OR_ZERO(opp);
> +       if (ret) {
> +               pr_err("%s[%d], cannot find opp with voltage=%d: %d\n",
> +                      __func__, __LINE__, cci_df->proc_reg_uV, ret);
> +               return ret;
> +       }
>         *freq = dev_pm_opp_get_freq(opp);
>
>         return 0;
> @@ -87,9 +135,11 @@ static int mtk_cci_governor_event_handler(struct devfreq *devfreq,
>         int ret;
>         struct cci_devfreq *cci_df;
>         struct notifier_block *nb;
> +       struct notifier_block *opp_nb;
>
>         cci_df = dev_get_drvdata(devfreq->dev.parent);
>         nb = &cci_df->nb;
> +       opp_nb = &cci_df->opp_nb;
>
>         switch (event) {
>         case DEVFREQ_GOV_START:
> @@ -100,6 +150,8 @@ static int mtk_cci_governor_event_handler(struct devfreq *devfreq,
>                 if (ret)
>                         pr_err("%s: failed to add governor: %d\n", __func__,
>                                ret);
> +               opp_nb->notifier_call = ccidevfreq_opp_notifier;
> +               dev_pm_opp_register_notifier(devfreq->dev.parent, opp_nb);
>                 break;
>
>         case DEVFREQ_GOV_STOP:
> @@ -141,6 +193,8 @@ static int mtk_cci_devfreq_target(struct device *dev, unsigned long *freq,
>                 return ret;
>         }
>
> +       cci_df->freq = *freq;
> +
>         return 0;
>  }
>
> @@ -152,6 +206,8 @@ static int mtk_cci_devfreq_probe(struct platform_device *pdev)
>  {
>         struct device *cci_dev = &pdev->dev;
>         struct cci_devfreq *cci_df;
> +       unsigned long freq, volt;
> +       struct dev_pm_opp *opp;
>         int ret;
>
>         cci_df = devm_kzalloc(cci_dev, sizeof(*cci_df), GFP_KERNEL);
> @@ -181,6 +237,13 @@ static int mtk_cci_devfreq_probe(struct platform_device *pdev)
>                 return ret;
>         }
>
> +       /* set voltage lower bound */
> +       freq = 1;
> +       opp = dev_pm_opp_find_freq_ceil(cci_dev, &freq);
> +       cci_df->cci_min_freq = dev_pm_opp_get_freq(opp);
> +       volt = dev_pm_opp_get_voltage(opp);
> +       dev_pm_opp_put(opp);
> +
>         platform_set_drvdata(pdev, cci_df);
>
>         cci_df->devfreq = devm_devfreq_add_device(cci_dev,

Re: [PATCH 8/8] devfreq: mediatek: cci devfreq register opp notification for SVS support

[Hsin-Yi Wang]

On Thu, May 16, 2019 at 9:08 AM Andrew-sh.Cheng
<andrew-sh.cheng@mediatek.com> wrote:
>
> From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>
>
> SVS will change the voltage of opp item.
> CCI devfreq need to react to change frequency.
>
> Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
> ---
>  drivers/devfreq/mt8183-cci-devfreq.c | 63 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 63 insertions(+)
>
> diff --git a/drivers/devfreq/mt8183-cci-devfreq.c b/drivers/devfreq/mt8183-cci-devfreq.c
> index 818a167c442f..250c963789f3 100644
> --- a/drivers/devfreq/mt8183-cci-devfreq.c
> +++ b/drivers/devfreq/mt8183-cci-devfreq.c
> @@ -19,7 +19,10 @@ struct cci_devfreq {
>         struct regulator *proc_reg;
>         unsigned long proc_reg_uV;
>         struct clk *cci_clk;
> +       unsigned long freq;
>         struct notifier_block nb;
> +       struct notifier_block opp_nb;
> +       int cci_min_freq;
>  };
>
>  static int cci_devfreq_regulator_notifier(struct notifier_block *nb,
> @@ -65,17 +68,62 @@ static int cci_devfreq_regulator_notifier(struct notifier_block *nb,
>         return 0;
>  }
>
> +static int ccidevfreq_opp_notifier(struct notifier_block *nb,
> +unsigned long event, void *data)
> +{
> +       int ret;
> +       struct dev_pm_opp *opp = data;
> +       struct cci_devfreq *cci_df = container_of(nb, struct cci_devfreq,
> +                                                 opp_nb);
> +       unsigned long   freq, volt, cur_volt;
> +
> +       if (event == OPP_EVENT_ADJUST_VOLTAGE) {
> +               freq = dev_pm_opp_get_freq(opp);
> +               /* current opp item is changed */
> +               if (freq == cci_df->freq) {
> +                       volt = dev_pm_opp_get_voltage(opp);
> +                       cur_volt = regulator_get_voltage(cci_df->proc_reg);
> +
> +                       if (volt > cur_volt) {
> +                               /* need reduce freq */
> +                               mutex_lock(&cci_df->devfreq->lock);
> +                               ret = update_devfreq(cci_df->devfreq);
> +                               if (ret)
> +                                       pr_err("Fail to reduce cci frequency by opp notification: %d\n",
This line is too long
> +                                              ret);
> +                               mutex_unlock(&cci_df->devfreq->lock);
> +                       }
> +               }
> +
> +               if (freq == cci_df->cci_min_freq) {
> +                       volt = dev_pm_opp_get_voltage(opp);
> +                       regulator_set_voltage(cci_df->proc_reg, volt, INT_MAX);
> +               }
> +       } else if (event == OPP_EVENT_DISABLE) {
Is this case handled? If not, is this branch needed?
> +       }
> +
> +       return 0;
> +}
> +
> +
>  static int mtk_cci_governor_get_target(struct devfreq *devfreq,
>                                        unsigned long *freq)
>  {
>         struct cci_devfreq *cci_df;
>         struct dev_pm_opp *opp;
> +       int ret;
>
>         cci_df = dev_get_drvdata(devfreq->dev.parent);
>
>         /* find available frequency */
>         opp = dev_pm_opp_find_freq_ceil_by_volt(devfreq->dev.parent,
>                                                 cci_df->proc_reg_uV);
> +       ret = PTR_ERR_OR_ZERO(opp);
> +       if (ret) {
> +               pr_err("%s[%d], cannot find opp with voltage=%d: %d\n",
> +                      __func__, __LINE__, cci_df->proc_reg_uV, ret);
> +               return ret;
> +       }
>         *freq = dev_pm_opp_get_freq(opp);
>
>         return 0;
> @@ -87,9 +135,11 @@ static int mtk_cci_governor_event_handler(struct devfreq *devfreq,
>         int ret;
>         struct cci_devfreq *cci_df;
>         struct notifier_block *nb;
> +       struct notifier_block *opp_nb;
>
>         cci_df = dev_get_drvdata(devfreq->dev.parent);
>         nb = &cci_df->nb;
> +       opp_nb = &cci_df->opp_nb;
>
>         switch (event) {
>         case DEVFREQ_GOV_START:
> @@ -100,6 +150,8 @@ static int mtk_cci_governor_event_handler(struct devfreq *devfreq,
>                 if (ret)
>                         pr_err("%s: failed to add governor: %d\n", __func__,
>                                ret);
> +               opp_nb->notifier_call = ccidevfreq_opp_notifier;
> +               dev_pm_opp_register_notifier(devfreq->dev.parent, opp_nb);
>                 break;
>
>         case DEVFREQ_GOV_STOP:
> @@ -141,6 +193,8 @@ static int mtk_cci_devfreq_target(struct device *dev, unsigned long *freq,
>                 return ret;
>         }
>
> +       cci_df->freq = *freq;
> +
>         return 0;
>  }
>
> @@ -152,6 +206,8 @@ static int mtk_cci_devfreq_probe(struct platform_device *pdev)
>  {
>         struct device *cci_dev = &pdev->dev;
>         struct cci_devfreq *cci_df;
> +       unsigned long freq, volt;
> +       struct dev_pm_opp *opp;
>         int ret;
>
>         cci_df = devm_kzalloc(cci_dev, sizeof(*cci_df), GFP_KERNEL);
> @@ -181,6 +237,13 @@ static int mtk_cci_devfreq_probe(struct platform_device *pdev)
>                 return ret;
>         }
>
> +       /* set voltage lower bound */
> +       freq = 1;
> +       opp = dev_pm_opp_find_freq_ceil(cci_dev, &freq);
> +       cci_df->cci_min_freq = dev_pm_opp_get_freq(opp);
> +       volt = dev_pm_opp_get_voltage(opp);
> +       dev_pm_opp_put(opp);
> +
>         platform_set_drvdata(pdev, cci_df);
>
>         cci_df->devfreq = devm_devfreq_add_device(cci_dev,

Re: [PATCH 8/8] devfreq: mediatek: cci devfreq register opp notification for SVS support

[Hsin-Yi Wang]

On Thu, May 16, 2019 at 9:08 AM Andrew-sh.Cheng
<andrew-sh.cheng@mediatek.com> wrote:
>
> From: "Andrew-sh.Cheng" <andrew-sh.cheng@mediatek.com>
>
> SVS will change the voltage of opp item.
> CCI devfreq need to react to change frequency.
>
> Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng@mediatek.com>
> ---
>  drivers/devfreq/mt8183-cci-devfreq.c | 63 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 63 insertions(+)
>
> diff --git a/drivers/devfreq/mt8183-cci-devfreq.c b/drivers/devfreq/mt8183-cci-devfreq.c
> index 818a167c442f..250c963789f3 100644
> --- a/drivers/devfreq/mt8183-cci-devfreq.c
> +++ b/drivers/devfreq/mt8183-cci-devfreq.c
> @@ -19,7 +19,10 @@ struct cci_devfreq {
>         struct regulator *proc_reg;
>         unsigned long proc_reg_uV;
>         struct clk *cci_clk;
> +       unsigned long freq;
>         struct notifier_block nb;
> +       struct notifier_block opp_nb;
> +       int cci_min_freq;
>  };
>
>  static int cci_devfreq_regulator_notifier(struct notifier_block *nb,
> @@ -65,17 +68,62 @@ static int cci_devfreq_regulator_notifier(struct notifier_block *nb,
>         return 0;
>  }
>
> +static int ccidevfreq_opp_notifier(struct notifier_block *nb,
> +unsigned long event, void *data)
> +{
> +       int ret;
> +       struct dev_pm_opp *opp = data;
> +       struct cci_devfreq *cci_df = container_of(nb, struct cci_devfreq,
> +                                                 opp_nb);
> +       unsigned long   freq, volt, cur_volt;
> +
> +       if (event == OPP_EVENT_ADJUST_VOLTAGE) {
> +               freq = dev_pm_opp_get_freq(opp);
> +               /* current opp item is changed */
> +               if (freq == cci_df->freq) {
> +                       volt = dev_pm_opp_get_voltage(opp);
> +                       cur_volt = regulator_get_voltage(cci_df->proc_reg);
> +
> +                       if (volt > cur_volt) {
> +                               /* need reduce freq */
> +                               mutex_lock(&cci_df->devfreq->lock);
> +                               ret = update_devfreq(cci_df->devfreq);
> +                               if (ret)
> +                                       pr_err("Fail to reduce cci frequency by opp notification: %d\n",
This line is too long
> +                                              ret);
> +                               mutex_unlock(&cci_df->devfreq->lock);
> +                       }
> +               }
> +
> +               if (freq == cci_df->cci_min_freq) {
> +                       volt = dev_pm_opp_get_voltage(opp);
> +                       regulator_set_voltage(cci_df->proc_reg, volt, INT_MAX);
> +               }
> +       } else if (event == OPP_EVENT_DISABLE) {
Is this case handled? If not, is this branch needed?
> +       }
> +
> +       return 0;
> +}
> +
> +
>  static int mtk_cci_governor_get_target(struct devfreq *devfreq,
>                                        unsigned long *freq)
>  {
>         struct cci_devfreq *cci_df;
>         struct dev_pm_opp *opp;
> +       int ret;
>
>         cci_df = dev_get_drvdata(devfreq->dev.parent);
>
>         /* find available frequency */
>         opp = dev_pm_opp_find_freq_ceil_by_volt(devfreq->dev.parent,
>                                                 cci_df->proc_reg_uV);
> +       ret = PTR_ERR_OR_ZERO(opp);
> +       if (ret) {
> +               pr_err("%s[%d], cannot find opp with voltage=%d: %d\n",
> +                      __func__, __LINE__, cci_df->proc_reg_uV, ret);
> +               return ret;
> +       }
>         *freq = dev_pm_opp_get_freq(opp);
>
>         return 0;
> @@ -87,9 +135,11 @@ static int mtk_cci_governor_event_handler(struct devfreq *devfreq,
>         int ret;
>         struct cci_devfreq *cci_df;
>         struct notifier_block *nb;
> +       struct notifier_block *opp_nb;
>
>         cci_df = dev_get_drvdata(devfreq->dev.parent);
>         nb = &cci_df->nb;
> +       opp_nb = &cci_df->opp_nb;
>
>         switch (event) {
>         case DEVFREQ_GOV_START:
> @@ -100,6 +150,8 @@ static int mtk_cci_governor_event_handler(struct devfreq *devfreq,
>                 if (ret)
>                         pr_err("%s: failed to add governor: %d\n", __func__,
>                                ret);
> +               opp_nb->notifier_call = ccidevfreq_opp_notifier;
> +               dev_pm_opp_register_notifier(devfreq->dev.parent, opp_nb);
>                 break;
>
>         case DEVFREQ_GOV_STOP:
> @@ -141,6 +193,8 @@ static int mtk_cci_devfreq_target(struct device *dev, unsigned long *freq,
>                 return ret;
>         }
>
> +       cci_df->freq = *freq;
> +
>         return 0;
>  }
>
> @@ -152,6 +206,8 @@ static int mtk_cci_devfreq_probe(struct platform_device *pdev)
>  {
>         struct device *cci_dev = &pdev->dev;
>         struct cci_devfreq *cci_df;
> +       unsigned long freq, volt;
> +       struct dev_pm_opp *opp;
>         int ret;
>
>         cci_df = devm_kzalloc(cci_dev, sizeof(*cci_df), GFP_KERNEL);
> @@ -181,6 +237,13 @@ static int mtk_cci_devfreq_probe(struct platform_device *pdev)
>                 return ret;
>         }
>
> +       /* set voltage lower bound */
> +       freq = 1;
> +       opp = dev_pm_opp_find_freq_ceil(cci_dev, &freq);
> +       cci_df->cci_min_freq = dev_pm_opp_get_freq(opp);
> +       volt = dev_pm_opp_get_voltage(opp);
> +       dev_pm_opp_put(opp);
> +
>         platform_set_drvdata(pdev, cci_df);
>
>         cci_df->devfreq = devm_devfreq_add_device(cci_dev,

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH 7/8] cpufreq: mediatek: add opp notification for SVS support

[Hsin-Yi Wang]

On Thu, May 16, 2019 at 9:08 AM Andrew-sh.Cheng
<andrew-sh.cheng@mediatek.com> wrote:
>         bool need_voltage_tracking;
> +       struct mutex lock; /* avoid notify and policy race condition */
> +       struct notifier_block opp_nb;
> +       int opp_cpu;
> +       unsigned long opp_freq;
>  };
>
>  static LIST_HEAD(dvfs_info_list);
> @@ -239,6 +243,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
>         vproc = dev_pm_opp_get_voltage(opp);
>         dev_pm_opp_put(opp);
>
> +       mutex_lock(&info->lock);

Should init mutex, otherwise it'll get lockdep warning:
[    0.587055] Call trace:
[    0.587069]  dump_backtrace+0x0/0x168
[    0.587077]  show_stack+0x20/0x2c
[    0.587086]  dump_stack+0xe4/0x134
[    0.587095]  register_lock_class+0x3e8/0x4b0
[    0.587103]  __lock_acquire+0xac/0x14e8
[    0.587110]  lock_acquire+0x1d0/0x208
[    0.587118]  __mutex_lock_common+0xc0/0xb40
[    0.587126]  mutex_lock_nested+0x40/0x50
[    0.587135]  mtk_cpufreq_set_target+0xcc/0x2a8
[    0.587143]  __cpufreq_driver_target+0x438/0x4d8
[    0.587150]  cpufreq_online+0x5b4/0x6e0
[    0.587156]  cpufreq_add_dev+0x4c/0x84
[    0.587164]  subsys_interface_register+0xb8/0x10c
[    0.587171]  cpufreq_register_driver+0x11c/0x1c0
[    0.587178]  mtk_cpufreq_probe+0x378/0x4b8
[    0.587185]  platform_drv_probe+0x80/0xb0
[    0.587192]  really_probe+0x114/0x28c
[    0.587198]  driver_probe_device+0x64/0xfc
[    0.587205]  __device_attach_driver+0xb8/0xd0
[    0.587211]  bus_for_each_drv+0x88/0xd0
[    0.587218]  __device_attach+0xb0/0x134
[    0.587224]  device_initial_probe+0x20/0x2c
[    0.587230]  bus_probe_device+0x34/0x94
[    0.587238]  device_add+0x520/0x5b4
[    0.587245]  platform_device_add+0x17c/0x208
[    0.587252]  platform_device_register_full+0xc0/0x100
[    0.587261]  mtk_cpufreq_driver_init+0x8c/0xdc
[    0.587268]  do_one_initcall+0x1c0/0x3e0
[    0.587276]  do_initcall_level+0x1f4/0x224
[    0.587282]  do_basic_setup+0x34/0x4c
[    0.587288]  kernel_init_freeable+0x10c/0x194
[    0.587295]  kernel_init+0x14/0x100
[    0.587302]  ret_from_fork+0x10/0x18
[    0.587510] cpufreq: cpufreq_online: CPU4: Unlisted initial
frequency changed to: 1248000 KHz

Re: [PATCH 7/8] cpufreq: mediatek: add opp notification for SVS support

[Hsin-Yi Wang]

On Thu, May 16, 2019 at 9:08 AM Andrew-sh.Cheng
<andrew-sh.cheng@mediatek.com> wrote:
>         bool need_voltage_tracking;
> +       struct mutex lock; /* avoid notify and policy race condition */
> +       struct notifier_block opp_nb;
> +       int opp_cpu;
> +       unsigned long opp_freq;
>  };
>
>  static LIST_HEAD(dvfs_info_list);
> @@ -239,6 +243,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
>         vproc = dev_pm_opp_get_voltage(opp);
>         dev_pm_opp_put(opp);
>
> +       mutex_lock(&info->lock);

Should init mutex, otherwise it'll get lockdep warning:
[    0.587055] Call trace:
[    0.587069]  dump_backtrace+0x0/0x168
[    0.587077]  show_stack+0x20/0x2c
[    0.587086]  dump_stack+0xe4/0x134
[    0.587095]  register_lock_class+0x3e8/0x4b0
[    0.587103]  __lock_acquire+0xac/0x14e8
[    0.587110]  lock_acquire+0x1d0/0x208
[    0.587118]  __mutex_lock_common+0xc0/0xb40
[    0.587126]  mutex_lock_nested+0x40/0x50
[    0.587135]  mtk_cpufreq_set_target+0xcc/0x2a8
[    0.587143]  __cpufreq_driver_target+0x438/0x4d8
[    0.587150]  cpufreq_online+0x5b4/0x6e0
[    0.587156]  cpufreq_add_dev+0x4c/0x84
[    0.587164]  subsys_interface_register+0xb8/0x10c
[    0.587171]  cpufreq_register_driver+0x11c/0x1c0
[    0.587178]  mtk_cpufreq_probe+0x378/0x4b8
[    0.587185]  platform_drv_probe+0x80/0xb0
[    0.587192]  really_probe+0x114/0x28c
[    0.587198]  driver_probe_device+0x64/0xfc
[    0.587205]  __device_attach_driver+0xb8/0xd0
[    0.587211]  bus_for_each_drv+0x88/0xd0
[    0.587218]  __device_attach+0xb0/0x134
[    0.587224]  device_initial_probe+0x20/0x2c
[    0.587230]  bus_probe_device+0x34/0x94
[    0.587238]  device_add+0x520/0x5b4
[    0.587245]  platform_device_add+0x17c/0x208
[    0.587252]  platform_device_register_full+0xc0/0x100
[    0.587261]  mtk_cpufreq_driver_init+0x8c/0xdc
[    0.587268]  do_one_initcall+0x1c0/0x3e0
[    0.587276]  do_initcall_level+0x1f4/0x224
[    0.587282]  do_basic_setup+0x34/0x4c
[    0.587288]  kernel_init_freeable+0x10c/0x194
[    0.587295]  kernel_init+0x14/0x100
[    0.587302]  ret_from_fork+0x10/0x18
[    0.587510] cpufreq: cpufreq_online: CPU4: Unlisted initial
frequency changed to: 1248000 KHz

Re: [PATCH 7/8] cpufreq: mediatek: add opp notification for SVS support

[Hsin-Yi Wang]

On Thu, May 16, 2019 at 9:08 AM Andrew-sh.Cheng
<andrew-sh.cheng@mediatek.com> wrote:
>         bool need_voltage_tracking;
> +       struct mutex lock; /* avoid notify and policy race condition */
> +       struct notifier_block opp_nb;
> +       int opp_cpu;
> +       unsigned long opp_freq;
>  };
>
>  static LIST_HEAD(dvfs_info_list);
> @@ -239,6 +243,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
>         vproc = dev_pm_opp_get_voltage(opp);
>         dev_pm_opp_put(opp);
>
> +       mutex_lock(&info->lock);

Should init mutex, otherwise it'll get lockdep warning:
[    0.587055] Call trace:
[    0.587069]  dump_backtrace+0x0/0x168
[    0.587077]  show_stack+0x20/0x2c
[    0.587086]  dump_stack+0xe4/0x134
[    0.587095]  register_lock_class+0x3e8/0x4b0
[    0.587103]  __lock_acquire+0xac/0x14e8
[    0.587110]  lock_acquire+0x1d0/0x208
[    0.587118]  __mutex_lock_common+0xc0/0xb40
[    0.587126]  mutex_lock_nested+0x40/0x50
[    0.587135]  mtk_cpufreq_set_target+0xcc/0x2a8
[    0.587143]  __cpufreq_driver_target+0x438/0x4d8
[    0.587150]  cpufreq_online+0x5b4/0x6e0
[    0.587156]  cpufreq_add_dev+0x4c/0x84
[    0.587164]  subsys_interface_register+0xb8/0x10c
[    0.587171]  cpufreq_register_driver+0x11c/0x1c0
[    0.587178]  mtk_cpufreq_probe+0x378/0x4b8
[    0.587185]  platform_drv_probe+0x80/0xb0
[    0.587192]  really_probe+0x114/0x28c
[    0.587198]  driver_probe_device+0x64/0xfc
[    0.587205]  __device_attach_driver+0xb8/0xd0
[    0.587211]  bus_for_each_drv+0x88/0xd0
[    0.587218]  __device_attach+0xb0/0x134
[    0.587224]  device_initial_probe+0x20/0x2c
[    0.587230]  bus_probe_device+0x34/0x94
[    0.587238]  device_add+0x520/0x5b4
[    0.587245]  platform_device_add+0x17c/0x208
[    0.587252]  platform_device_register_full+0xc0/0x100
[    0.587261]  mtk_cpufreq_driver_init+0x8c/0xdc
[    0.587268]  do_one_initcall+0x1c0/0x3e0
[    0.587276]  do_initcall_level+0x1f4/0x224
[    0.587282]  do_basic_setup+0x34/0x4c
[    0.587288]  kernel_init_freeable+0x10c/0x194
[    0.587295]  kernel_init+0x14/0x100
[    0.587302]  ret_from_fork+0x10/0x18
[    0.587510] cpufreq: cpufreq_online: CPU4: Unlisted initial
frequency changed to: 1248000 KHz

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH 6/8] PM / OPP: Support adjusting OPP voltages at runtime

[Roger Lu]

Dear Stephen Boyd,

This patch is derived from [1]. Please kindly shares the suggestion to
us. Thanks very much.

[1]: https://lore.kernel.org/patchwork/patch/599279/

Dear Viresh,

I followed _opp_set_availability() coding style to refine
dev_pm_opp_adjust_voltage() from this patch. Is this refinement suitable
for OPP core? Thanks a lot.

On Mon, 2019-05-20 at 12:47 +0800, Viresh Kumar wrote:
> On 16-05-19, 17:08, Andrew-sh.Cheng wrote:
> > From: Stephen Boyd <sboyd@codeaurora.org>
> > 
> > On some SoCs the Adaptive Voltage Scaling (AVS) technique is
> > employed to optimize the operating voltage of a device. At a
> > given frequency, the hardware monitors dynamic factors and either
> > makes a suggestion for how much to adjust a voltage for the
> > current frequency, or it automatically adjusts the voltage
> > without software intervention. Add an API to the OPP library for
> > the former case, so that AVS type devices can update the voltages
> > for an OPP when the hardware determines the voltage should
> > change. The assumption is that drivers like CPUfreq or devfreq
> > will register for the OPP notifiers and adjust the voltage
> > according to suggestions that AVS makes.
> > 
> > This patch is devired from [1] submitted by Stephen.
> > [1] https://lore.kernel.org/patchwork/patch/599279/
> > 
> > Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
> > Signed-off-by: Roger Lu <roger.lu@mediatek.com>
> > ---
> >  drivers/opp/core.c     | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++
> >  include/linux/pm_opp.h | 11 +++++++
> >  2 files changed, 89 insertions(+)
> 
> This is an rcu implementation which got removed long back from OPP core. Please
> align this with the latest changes.
> 


/**
 * dev_pm_opp_adjust_voltage() - helper to change the voltage of an OPP
 * @dev:		device for which we do this operation
 * @freq:		OPP frequency to adjust voltage of
 * @u_volt:		new OPP voltage
 *
 * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for
the
 * copy operation, returns 0 if no modifcation was done OR modification
was
 * successful.
 */
int dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq,
			      unsigned long u_volt)
{
	struct opp_table *opp_table;
	struct dev_pm_opp *tmp_opp, *opp = ERR_PTR(-ENODEV);
	int r = 0;

	/* Find the opp_table */
	opp_table = _find_opp_table(dev);
	if (IS_ERR(opp_table)) {
		r = PTR_ERR(opp_table);
		dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r);
		return r;
	}

	mutex_lock(&opp_table->lock);

	/* Do we have the frequency? */
	list_for_each_entry(tmp_opp, &opp_table->opp_list, node) {
		if (tmp_opp->rate == freq) {
			opp = tmp_opp;
			break;
		}
	}

	if (IS_ERR(opp)) {
		r = PTR_ERR(opp);
		goto adjust_unlock;
	}

	/* Is update really needed? */
	if (opp->supplies->u_volt == u_volt)
		goto adjust_unlock;

	opp->supplies->u_volt = u_volt;

	dev_pm_opp_get(opp);
	mutex_unlock(&opp_table->lock);

	/* Notify the voltage change of the OPP */
	blocking_notifier_call_chain(&opp_table->head,
OPP_EVENT_ADJUST_VOLTAGE,
				     opp);

	dev_pm_opp_put(opp);
	goto adjust_put_table;

adjust_unlock:
	mutex_unlock(&opp_table->lock);
adjust_put_table:
	dev_pm_opp_put_opp_table(opp_table);
	return r;
}

Sincerely,
Roger Lu.

Re: [PATCH 6/8] PM / OPP: Support adjusting OPP voltages at runtime

[Roger Lu]

Dear Stephen Boyd,

This patch is derived from [1]. Please kindly shares the suggestion to
us. Thanks very much.

[1]: https://lore.kernel.org/patchwork/patch/599279/

Dear Viresh,

I followed _opp_set_availability() coding style to refine
dev_pm_opp_adjust_voltage() from this patch. Is this refinement suitable
for OPP core? Thanks a lot.

On Mon, 2019-05-20 at 12:47 +0800, Viresh Kumar wrote:
> On 16-05-19, 17:08, Andrew-sh.Cheng wrote:
> > From: Stephen Boyd <sboyd@codeaurora.org>
> > 
> > On some SoCs the Adaptive Voltage Scaling (AVS) technique is
> > employed to optimize the operating voltage of a device. At a
> > given frequency, the hardware monitors dynamic factors and either
> > makes a suggestion for how much to adjust a voltage for the
> > current frequency, or it automatically adjusts the voltage
> > without software intervention. Add an API to the OPP library for
> > the former case, so that AVS type devices can update the voltages
> > for an OPP when the hardware determines the voltage should
> > change. The assumption is that drivers like CPUfreq or devfreq
> > will register for the OPP notifiers and adjust the voltage
> > according to suggestions that AVS makes.
> > 
> > This patch is devired from [1] submitted by Stephen.
> > [1] https://lore.kernel.org/patchwork/patch/599279/
> > 
> > Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
> > Signed-off-by: Roger Lu <roger.lu@mediatek.com>
> > ---
> >  drivers/opp/core.c     | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++
> >  include/linux/pm_opp.h | 11 +++++++
> >  2 files changed, 89 insertions(+)
> 
> This is an rcu implementation which got removed long back from OPP core. Please
> align this with the latest changes.
> 


/**
 * dev_pm_opp_adjust_voltage() - helper to change the voltage of an OPP
 * @dev:		device for which we do this operation
 * @freq:		OPP frequency to adjust voltage of
 * @u_volt:		new OPP voltage
 *
 * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for
the
 * copy operation, returns 0 if no modifcation was done OR modification
was
 * successful.
 */
int dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq,
			      unsigned long u_volt)
{
	struct opp_table *opp_table;
	struct dev_pm_opp *tmp_opp, *opp = ERR_PTR(-ENODEV);
	int r = 0;

	/* Find the opp_table */
	opp_table = _find_opp_table(dev);
	if (IS_ERR(opp_table)) {
		r = PTR_ERR(opp_table);
		dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r);
		return r;
	}

	mutex_lock(&opp_table->lock);

	/* Do we have the frequency? */
	list_for_each_entry(tmp_opp, &opp_table->opp_list, node) {
		if (tmp_opp->rate == freq) {
			opp = tmp_opp;
			break;
		}
	}

	if (IS_ERR(opp)) {
		r = PTR_ERR(opp);
		goto adjust_unlock;
	}

	/* Is update really needed? */
	if (opp->supplies->u_volt == u_volt)
		goto adjust_unlock;

	opp->supplies->u_volt = u_volt;

	dev_pm_opp_get(opp);
	mutex_unlock(&opp_table->lock);

	/* Notify the voltage change of the OPP */
	blocking_notifier_call_chain(&opp_table->head,
OPP_EVENT_ADJUST_VOLTAGE,
				     opp);

	dev_pm_opp_put(opp);
	goto adjust_put_table;

adjust_unlock:
	mutex_unlock(&opp_table->lock);
adjust_put_table:
	dev_pm_opp_put_opp_table(opp_table);
	return r;
}

Sincerely,
Roger Lu.

Re: [PATCH 6/8] PM / OPP: Support adjusting OPP voltages at runtime

[Roger Lu]

Dear Stephen Boyd,

This patch is derived from [1]. Please kindly shares the suggestion to
us. Thanks very much.

[1]: https://lore.kernel.org/patchwork/patch/599279/

Dear Viresh,

I followed _opp_set_availability() coding style to refine
dev_pm_opp_adjust_voltage() from this patch. Is this refinement suitable
for OPP core? Thanks a lot.

On Mon, 2019-05-20 at 12:47 +0800, Viresh Kumar wrote:
> On 16-05-19, 17:08, Andrew-sh.Cheng wrote:
> > From: Stephen Boyd <sboyd@codeaurora.org>
> > 
> > On some SoCs the Adaptive Voltage Scaling (AVS) technique is
> > employed to optimize the operating voltage of a device. At a
> > given frequency, the hardware monitors dynamic factors and either
> > makes a suggestion for how much to adjust a voltage for the
> > current frequency, or it automatically adjusts the voltage
> > without software intervention. Add an API to the OPP library for
> > the former case, so that AVS type devices can update the voltages
> > for an OPP when the hardware determines the voltage should
> > change. The assumption is that drivers like CPUfreq or devfreq
> > will register for the OPP notifiers and adjust the voltage
> > according to suggestions that AVS makes.
> > 
> > This patch is devired from [1] submitted by Stephen.
> > [1] https://lore.kernel.org/patchwork/patch/599279/
> > 
> > Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
> > Signed-off-by: Roger Lu <roger.lu@mediatek.com>
> > ---
> >  drivers/opp/core.c     | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++
> >  include/linux/pm_opp.h | 11 +++++++
> >  2 files changed, 89 insertions(+)
> 
> This is an rcu implementation which got removed long back from OPP core. Please
> align this with the latest changes.
> 


/**
 * dev_pm_opp_adjust_voltage() - helper to change the voltage of an OPP
 * @dev:		device for which we do this operation
 * @freq:		OPP frequency to adjust voltage of
 * @u_volt:		new OPP voltage
 *
 * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for
the
 * copy operation, returns 0 if no modifcation was done OR modification
was
 * successful.
 */
int dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq,
			      unsigned long u_volt)
{
	struct opp_table *opp_table;
	struct dev_pm_opp *tmp_opp, *opp = ERR_PTR(-ENODEV);
	int r = 0;

	/* Find the opp_table */
	opp_table = _find_opp_table(dev);
	if (IS_ERR(opp_table)) {
		r = PTR_ERR(opp_table);
		dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r);
		return r;
	}

	mutex_lock(&opp_table->lock);

	/* Do we have the frequency? */
	list_for_each_entry(tmp_opp, &opp_table->opp_list, node) {
		if (tmp_opp->rate == freq) {
			opp = tmp_opp;
			break;
		}
	}

	if (IS_ERR(opp)) {
		r = PTR_ERR(opp);
		goto adjust_unlock;
	}

	/* Is update really needed? */
	if (opp->supplies->u_volt == u_volt)
		goto adjust_unlock;

	opp->supplies->u_volt = u_volt;

	dev_pm_opp_get(opp);
	mutex_unlock(&opp_table->lock);

	/* Notify the voltage change of the OPP */
	blocking_notifier_call_chain(&opp_table->head,
OPP_EVENT_ADJUST_VOLTAGE,
				     opp);

	dev_pm_opp_put(opp);
	goto adjust_put_table;

adjust_unlock:
	mutex_unlock(&opp_table->lock);
adjust_put_table:
	dev_pm_opp_put_opp_table(opp_table);
	return r;
}

Sincerely,
Roger Lu.


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH 6/8] PM / OPP: Support adjusting OPP voltages at runtime

[Viresh Kumar]

On 29-07-19, 11:39, Roger Lu wrote:
> Dear Stephen Boyd,
> 
> This patch is derived from [1]. Please kindly shares the suggestion to
> us. Thanks very much.
> 
> [1]: https://lore.kernel.org/patchwork/patch/599279/
> 
> Dear Viresh,
> 
> I followed _opp_set_availability() coding style to refine
> dev_pm_opp_adjust_voltage() from this patch. Is this refinement suitable
> for OPP core? Thanks a lot.

Looks okay from a quick look.

-- 
viresh

Re: [PATCH 6/8] PM / OPP: Support adjusting OPP voltages at runtime

[Viresh Kumar]

On 29-07-19, 11:39, Roger Lu wrote:
> Dear Stephen Boyd,
> 
> This patch is derived from [1]. Please kindly shares the suggestion to
> us. Thanks very much.
> 
> [1]: https://lore.kernel.org/patchwork/patch/599279/
> 
> Dear Viresh,
> 
> I followed _opp_set_availability() coding style to refine
> dev_pm_opp_adjust_voltage() from this patch. Is this refinement suitable
> for OPP core? Thanks a lot.

Looks okay from a quick look.

-- 
viresh

Re: [PATCH 6/8] PM / OPP: Support adjusting OPP voltages at runtime

[Viresh Kumar]

On 29-07-19, 11:39, Roger Lu wrote:
> Dear Stephen Boyd,
> 
> This patch is derived from [1]. Please kindly shares the suggestion to
> us. Thanks very much.
> 
> [1]: https://lore.kernel.org/patchwork/patch/599279/
> 
> Dear Viresh,
> 
> I followed _opp_set_availability() coding style to refine
> dev_pm_opp_adjust_voltage() from this patch. Is this refinement suitable
> for OPP core? Thanks a lot.

Looks okay from a quick look.

-- 
viresh

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel