[PATCH 43 0/3] Kirkwoode cpufreq driver

[PATCH 43 0/3] Kirkwoode cpufreq driver

[Andrew Lunn]

This patchset adds a cpufreq driver for Marvell Kirkwood SoCs.

The changes to kirkwood_defconfig enable it and set the default
governor to ondemand.

Changes since v3:

Check return value of of_find_compatible_node()
Return -EADDRNOTAVAIL when devm_request_and_ioremap() fails.
Remove default: clause.
Made .name consistent.

Changes since v2:

Remove unneeded #include file left over from debugging.
WARN_ON(1) instead of dev_err() for unexpected state
Various blank lines removed.
Reformat comment.
writel -> writel_relaxed

Changes since v1:

tabify Kconfig.arm entry
Sort order of include files
Remove some unnecassary include files
Reformat multiline comment to be coding style conform.

Andrew Lunn (3):
  cpufreq: kirkwood: Add a cpufreq driver for Marvell Kirkwood SoCs
  arm: kirkwood: Instantiate cpufreq driver
  arm: kirkwood: Enable cpufreq and ondemand on kirkwood_defconfig

 arch/arm/Kconfig                                  |    1 +
 arch/arm/configs/kirkwood_defconfig               |    3 +
 arch/arm/mach-kirkwood/board-dt.c                 |    3 +-
 arch/arm/mach-kirkwood/common.c                   |   23 ++
 arch/arm/mach-kirkwood/common.h                   |    2 +
 arch/arm/mach-kirkwood/include/mach/bridge-regs.h |    2 +
 drivers/clk/mvebu/clk-gating-ctrl.c               |    1 +
 drivers/cpufreq/Kconfig.arm                       |    6 +
 drivers/cpufreq/Makefile                          |    1 +
 drivers/cpufreq/kirkwood-cpufreq.c                |  264 +++++++++++++++++++++
 10 files changed, 305 insertions(+), 1 deletion(-)
 create mode 100644 drivers/cpufreq/kirkwood-cpufreq.c

-- 
1.7.10.4

[PATCH v4 1/3] cpufreq: kirkwood: Add a cpufreq driver for Marvell Kirkwood SoCs

[Andrew Lunn]

The Marvell Kirkwood SoCs have simple cpufreq support in hardware. The
CPU can either use the a high speed cpu clock, or the slower DDR
clock. Add a driver to swap between these two clock sources.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Jason Cooper <jason@lakedaemon.net>
---

To be commited by: Rafael J. Wysocki

 drivers/clk/mvebu/clk-gating-ctrl.c |    1 +
 drivers/cpufreq/Kconfig.arm         |    6 +
 drivers/cpufreq/Makefile            |    1 +
 drivers/cpufreq/kirkwood-cpufreq.c  |  277 +++++++++++++++++++++++++++++++++++
 4 files changed, 285 insertions(+)
 create mode 100644 drivers/cpufreq/kirkwood-cpufreq.c

diff --git a/drivers/clk/mvebu/clk-gating-ctrl.c b/drivers/clk/mvebu/clk-gating-ctrl.c
index 8fa5408..ebf141d 100644
--- a/drivers/clk/mvebu/clk-gating-ctrl.c
+++ b/drivers/clk/mvebu/clk-gating-ctrl.c
@@ -193,6 +193,7 @@ static const struct mvebu_soc_descr __initconst kirkwood_gating_descr[] = {
 	{ "runit", NULL, 7 },
 	{ "xor0", NULL, 8 },
 	{ "audio", NULL, 9 },
+	{ "powersave", "cpuclk", 11 },
 	{ "sata0", NULL, 14 },
 	{ "sata1", NULL, 15 },
 	{ "xor1", NULL, 16 },
diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
index a0b3661..80c8229 100644
--- a/drivers/cpufreq/Kconfig.arm
+++ b/drivers/cpufreq/Kconfig.arm
@@ -77,6 +77,12 @@ config ARM_EXYNOS5250_CPUFREQ
 	  This adds the CPUFreq driver for Samsung EXYNOS5250
 	  SoC.
 
+config ARM_KIRKWOOD_CPUFREQ
+	def_bool ARCH_KIRKWOOD && OF
+	help
+	  This adds the CPUFreq driver for Marvell Kirkwood
+	  SoCs.
+
 config ARM_SPEAR_CPUFREQ
 	bool "SPEAr CPUFreq support"
 	depends on PLAT_SPEAR
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index fadc4d4..39a0ffe 100644
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -50,6 +50,7 @@ obj-$(CONFIG_ARM_EXYNOS_CPUFREQ)	+= exynos-cpufreq.o
 obj-$(CONFIG_ARM_EXYNOS4210_CPUFREQ)	+= exynos4210-cpufreq.o
 obj-$(CONFIG_ARM_EXYNOS4X12_CPUFREQ)	+= exynos4x12-cpufreq.o
 obj-$(CONFIG_ARM_EXYNOS5250_CPUFREQ)	+= exynos5250-cpufreq.o
+obj-$(CONFIG_ARM_KIRKWOOD_CPUFREQ)	+= kirkwood-cpufreq.o
 obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ)     += omap-cpufreq.o
 obj-$(CONFIG_ARM_SPEAR_CPUFREQ)		+= spear-cpufreq.o
 
diff --git a/drivers/cpufreq/kirkwood-cpufreq.c b/drivers/cpufreq/kirkwood-cpufreq.c
new file mode 100644
index 0000000..8923689
--- /dev/null
+++ b/drivers/cpufreq/kirkwood-cpufreq.c
@@ -0,0 +1,277 @@
+/*
+ *	kirkwood_freq.c: cpufreq driver for the Marvell kirkwood
+ *
+ *	Copyright (C) 2013 Andrew Lunn <andrew@lunn.ch>
+ *
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License
+ *	as published by the Free Software Foundation; either version
+ *	2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/cpufreq.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <asm/proc-fns.h>
+
+#define CPU_SW_INT_BLK BIT(28)
+
+static struct priv
+{
+	struct clk *cpu_clk;
+	struct clk *ddr_clk;
+	struct clk *powersave_clk;
+	struct device *dev;
+	void __iomem *base;
+} priv;
+
+#define STATE_CPU_FREQ 0x01
+#define STATE_DDR_FREQ 0x02
+
+/*
+ * Kirkwood can swap the clock to the CPU between two clocks:
+ *
+ * - cpu clk
+ * - ddr clk
+ *
+ * The frequencies are set at runtime before registering this *
+ * table.
+ */
+static struct cpufreq_frequency_table kirkwood_freq_table[] = {
+	{STATE_CPU_FREQ,	0}, /* CPU uses cpuclk */
+	{STATE_DDR_FREQ,	0}, /* CPU uses ddrclk */
+	{0,			CPUFREQ_TABLE_END},
+};
+
+static unsigned int kirkwood_cpufreq_get_cpu_frequency(unsigned int cpu)
+{
+	if (__clk_is_enabled(priv.powersave_clk))
+		return kirkwood_freq_table[1].frequency;
+	return kirkwood_freq_table[0].frequency;
+}
+
+static void kirkwood_cpufreq_set_cpu_state(unsigned int index)
+{
+	struct cpufreq_freqs freqs;
+	unsigned int state = kirkwood_freq_table[index].index;
+	unsigned long reg;
+
+	freqs.old = kirkwood_cpufreq_get_cpu_frequency(0);
+	freqs.new = kirkwood_freq_table[index].frequency;
+	freqs.cpu = 0; /* Kirkwood is UP */
+
+	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+
+	dev_dbg(priv.dev, "Attempting to set frequency to %i KHz\n",
+		kirkwood_freq_table[index].frequency);
+	dev_dbg(priv.dev, "old frequency was %i KHz\n",
+		kirkwood_cpufreq_get_cpu_frequency(0));
+
+	if (freqs.old != freqs.new) {
+		local_irq_disable();
+
+		/* Disable interrupts to the CPU */
+		reg = readl_relaxed(priv.base);
+		reg |= CPU_SW_INT_BLK;
+		writel_relaxed(reg, priv.base);
+
+		switch (state) {
+		case STATE_CPU_FREQ:
+			clk_disable(priv.powersave_clk);
+			break;
+		case STATE_DDR_FREQ:
+			clk_enable(priv.powersave_clk);
+			break;
+		}
+
+		/* Wait-for-Interrupt, while the hardware changes frequency */
+		cpu_do_idle();
+
+		/* Enable interrupts to the CPU */
+		reg = readl_relaxed(priv.base);
+		reg &= ~CPU_SW_INT_BLK;
+		writel_relaxed(reg, priv.base);
+
+		local_irq_enable();
+	}
+	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+};
+
+static int kirkwood_cpufreq_verify(struct cpufreq_policy *policy)
+{
+	return cpufreq_frequency_table_verify(policy, kirkwood_freq_table);
+}
+
+static int kirkwood_cpufreq_target(struct cpufreq_policy *policy,
+			    unsigned int target_freq,
+			    unsigned int relation)
+{
+	unsigned int index = 0;
+
+	if (cpufreq_frequency_table_target(policy, kirkwood_freq_table,
+				target_freq, relation, &index))
+		return -EINVAL;
+
+	kirkwood_cpufreq_set_cpu_state(index);
+
+	return 0;
+}
+
+/* Module init and exit code */
+static int kirkwood_cpufreq_cpu_init(struct cpufreq_policy *policy)
+{
+	int result;
+
+	/* cpuinfo and default policy values */
+	policy->cpuinfo.transition_latency = 5000; /* 5uS */
+	policy->cur = kirkwood_cpufreq_get_cpu_frequency(0);
+
+	result = cpufreq_frequency_table_cpuinfo(policy, kirkwood_freq_table);
+	if (result)
+		return result;
+
+	cpufreq_frequency_table_get_attr(kirkwood_freq_table, policy->cpu);
+
+	return 0;
+}
+
+static int kirkwood_cpufreq_cpu_exit(struct cpufreq_policy *policy)
+{
+	cpufreq_frequency_table_put_attr(policy->cpu);
+	return 0;
+}
+
+static struct freq_attr *kirkwood_cpufreq_attr[] = {
+	&cpufreq_freq_attr_scaling_available_freqs,
+	NULL,
+};
+
+static struct cpufreq_driver kirkwood_cpufreq_driver = {
+	.get	= kirkwood_cpufreq_get_cpu_frequency,
+	.verify	= kirkwood_cpufreq_verify,
+	.target	= kirkwood_cpufreq_target,
+	.init	= kirkwood_cpufreq_cpu_init,
+	.exit	= kirkwood_cpufreq_cpu_exit,
+	.name	= "kirkwood-cpufreq",
+	.owner	= THIS_MODULE,
+	.attr	= kirkwood_cpufreq_attr,
+};
+
+static int kirkwood_cpufreq_probe(struct platform_device *pdev)
+{
+	struct device_node *np_core = of_find_compatible_node(
+		NULL, NULL, "marvell,kirkwood-core-clock");
+	struct device_node *np_gating = of_find_compatible_node(
+		NULL, NULL, "marvell,kirkwood-gating-clock");
+	struct of_phandle_args clkspec;
+	struct resource *res;
+	int err;
+
+	if (!np_core || !np_gating) {
+		if (np_core)
+			of_node_put(np_core);
+		if (np_gating)
+			of_node_put(np_gating);
+		return -ENODEV;
+	}
+	
+	priv.dev = &pdev->dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "Cannot get memory resource\n");
+		return -ENODEV;
+	}
+	priv.base = devm_request_and_ioremap(&pdev->dev, res);
+	if (!priv.base) {
+		dev_err(&pdev->dev, "Cannot ioremap\n");
+		return -EADDRNOTAVAIL;
+	}
+
+	clkspec.np = np_core;
+	clkspec.args_count = 1;
+	clkspec.args[0] = 1;
+
+	priv.cpu_clk = of_clk_get_from_provider(&clkspec);
+	if (IS_ERR(priv.cpu_clk)) {
+		dev_err(priv.dev, "Unable to get cpuclk");
+		return PTR_ERR(priv.cpu_clk);
+	}
+
+	clk_prepare_enable(priv.cpu_clk);
+	kirkwood_freq_table[0].frequency = clk_get_rate(priv.cpu_clk) / 1000;
+
+	clkspec.args[0] = 3;
+	priv.ddr_clk = of_clk_get_from_provider(&clkspec);
+	if (IS_ERR(priv.ddr_clk)) {
+		dev_err(priv.dev, "Unable to get ddrclk");
+		err = PTR_ERR(priv.ddr_clk);
+		goto out_cpu;
+	}
+
+	clk_prepare_enable(priv.ddr_clk);
+	kirkwood_freq_table[1].frequency = clk_get_rate(priv.ddr_clk) / 1000;
+
+	clkspec.np = np_gating;
+	clkspec.args[0] = 11;
+	priv.powersave_clk = of_clk_get_from_provider(&clkspec);
+	if (IS_ERR(priv.powersave_clk)) {
+		dev_err(priv.dev, "Unable to get powersave");
+		err = PTR_ERR(priv.powersave_clk);
+		goto out_ddr;
+	}
+	clk_prepare(priv.powersave_clk);
+
+	of_node_put(np_core);
+	np_core = NULL;
+	of_node_put(np_gating);
+	np_gating = NULL;
+
+	err = cpufreq_register_driver(&kirkwood_cpufreq_driver);
+	if (!err)
+		return 0;
+
+	dev_err(priv.dev, "Failed to register cpufreq driver");
+
+	clk_disable_unprepare(priv.powersave_clk);
+out_ddr:
+	clk_disable_unprepare(priv.ddr_clk);
+out_cpu:
+	clk_disable_unprepare(priv.cpu_clk);
+	of_node_put(np_core);
+	of_node_put(np_gating);
+
+	return err;
+}
+
+static int kirkwood_cpufreq_remove(struct platform_device *pdev)
+{
+	cpufreq_unregister_driver(&kirkwood_cpufreq_driver);
+
+	clk_disable_unprepare(priv.powersave_clk);
+	clk_disable_unprepare(priv.ddr_clk);
+	clk_disable_unprepare(priv.cpu_clk);
+
+	return 0;
+}
+
+static struct platform_driver kirkwood_cpufreq_platform_driver = {
+	.probe = kirkwood_cpufreq_probe,
+	.remove = kirkwood_cpufreq_remove,
+	.driver = {
+		.name = "kirkwood-cpufreq",
+		.owner = THIS_MODULE,
+	},
+};
+
+module_platform_driver(kirkwood_cpufreq_platform_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch");
+MODULE_DESCRIPTION("cpufreq driver for Marvell's kirkwood CPU");
+MODULE_ALIAS("platform:kirkwood-cpufreq");
-- 
1.7.10.4

[PATCH v4 1/3] cpufreq: kirkwood: Add a cpufreq driver for Marvell Kirkwood SoCs

[Viresh Kumar]

On 1 February 2013 20:01, Andrew Lunn <andrew@lunn.ch> wrote:
> The Marvell Kirkwood SoCs have simple cpufreq support in hardware. The
> CPU can either use the a high speed cpu clock, or the slower DDR
> clock. Add a driver to swap between these two clock sources.
>
> Signed-off-by: Andrew Lunn <andrew@lunn.ch>
> Acked-by: Jason Cooper <jason@lakedaemon.net>

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

[PATCH v4 1/3] cpufreq: kirkwood: Add a cpufreq driver for Marvell Kirkwood SoCs

[Shawn Guo]

On Fri, Feb 01, 2013 at 03:31:33PM +0100, Andrew Lunn wrote:
> The Marvell Kirkwood SoCs have simple cpufreq support in hardware. The
> CPU can either use the a high speed cpu clock, or the slower DDR
> clock. Add a driver to swap between these two clock sources.
> 
> Signed-off-by: Andrew Lunn <andrew@lunn.ch>
> Acked-by: Jason Cooper <jason@lakedaemon.net>
> ---
> 
> To be commited by: Rafael J. Wysocki
> 
>  drivers/clk/mvebu/clk-gating-ctrl.c |    1 +
>  drivers/cpufreq/Kconfig.arm         |    6 +
>  drivers/cpufreq/Makefile            |    1 +
>  drivers/cpufreq/kirkwood-cpufreq.c  |  277 +++++++++++++++++++++++++++++++++++
>  4 files changed, 285 insertions(+)
>  create mode 100644 drivers/cpufreq/kirkwood-cpufreq.c
> 
> diff --git a/drivers/clk/mvebu/clk-gating-ctrl.c b/drivers/clk/mvebu/clk-gating-ctrl.c
> index 8fa5408..ebf141d 100644
> --- a/drivers/clk/mvebu/clk-gating-ctrl.c
> +++ b/drivers/clk/mvebu/clk-gating-ctrl.c
> @@ -193,6 +193,7 @@ static const struct mvebu_soc_descr __initconst kirkwood_gating_descr[] = {
>  	{ "runit", NULL, 7 },
>  	{ "xor0", NULL, 8 },
>  	{ "audio", NULL, 9 },
> +	{ "powersave", "cpuclk", 11 },
>  	{ "sata0", NULL, 14 },
>  	{ "sata1", NULL, 15 },
>  	{ "xor1", NULL, 16 },
> diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
> index a0b3661..80c8229 100644
> --- a/drivers/cpufreq/Kconfig.arm
> +++ b/drivers/cpufreq/Kconfig.arm
> @@ -77,6 +77,12 @@ config ARM_EXYNOS5250_CPUFREQ
>  	  This adds the CPUFreq driver for Samsung EXYNOS5250
>  	  SoC.
>  
> +config ARM_KIRKWOOD_CPUFREQ
> +	def_bool ARCH_KIRKWOOD && OF
> +	help
> +	  This adds the CPUFreq driver for Marvell Kirkwood
> +	  SoCs.
> +
>  config ARM_SPEAR_CPUFREQ
>  	bool "SPEAr CPUFreq support"
>  	depends on PLAT_SPEAR
> diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
> index fadc4d4..39a0ffe 100644
> --- a/drivers/cpufreq/Makefile
> +++ b/drivers/cpufreq/Makefile
> @@ -50,6 +50,7 @@ obj-$(CONFIG_ARM_EXYNOS_CPUFREQ)	+= exynos-cpufreq.o
>  obj-$(CONFIG_ARM_EXYNOS4210_CPUFREQ)	+= exynos4210-cpufreq.o
>  obj-$(CONFIG_ARM_EXYNOS4X12_CPUFREQ)	+= exynos4x12-cpufreq.o
>  obj-$(CONFIG_ARM_EXYNOS5250_CPUFREQ)	+= exynos5250-cpufreq.o
> +obj-$(CONFIG_ARM_KIRKWOOD_CPUFREQ)	+= kirkwood-cpufreq.o
>  obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ)     += omap-cpufreq.o
>  obj-$(CONFIG_ARM_SPEAR_CPUFREQ)		+= spear-cpufreq.o
>  
> diff --git a/drivers/cpufreq/kirkwood-cpufreq.c b/drivers/cpufreq/kirkwood-cpufreq.c
> new file mode 100644
> index 0000000..8923689
> --- /dev/null
> +++ b/drivers/cpufreq/kirkwood-cpufreq.c
> @@ -0,0 +1,277 @@
> +/*
> + *	kirkwood_freq.c: cpufreq driver for the Marvell kirkwood
> + *
> + *	Copyright (C) 2013 Andrew Lunn <andrew@lunn.ch>
> + *
> + *	This program is free software; you can redistribute it and/or
> + *	modify it under the terms of the GNU General Public License
> + *	as published by the Free Software Foundation; either version
> + *	2 of the License, or (at your option) any later version.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/clk.h>
> +#include <linux/clk-provider.h>

Why do you need this header?

> +#include <linux/cpufreq.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/io.h>
> +#include <asm/proc-fns.h>
> +
> +#define CPU_SW_INT_BLK BIT(28)
> +
> +static struct priv
> +{
> +	struct clk *cpu_clk;
> +	struct clk *ddr_clk;
> +	struct clk *powersave_clk;
> +	struct device *dev;
> +	void __iomem *base;
> +} priv;
> +
> +#define STATE_CPU_FREQ 0x01
> +#define STATE_DDR_FREQ 0x02
> +
> +/*
> + * Kirkwood can swap the clock to the CPU between two clocks:
> + *
> + * - cpu clk
> + * - ddr clk
> + *
> + * The frequencies are set at runtime before registering this *
> + * table.
> + */
> +static struct cpufreq_frequency_table kirkwood_freq_table[] = {
> +	{STATE_CPU_FREQ,	0}, /* CPU uses cpuclk */
> +	{STATE_DDR_FREQ,	0}, /* CPU uses ddrclk */
> +	{0,			CPUFREQ_TABLE_END},
> +};
> +
> +static unsigned int kirkwood_cpufreq_get_cpu_frequency(unsigned int cpu)
> +{
> +	if (__clk_is_enabled(priv.powersave_clk))
> +		return kirkwood_freq_table[1].frequency;
> +	return kirkwood_freq_table[0].frequency;
> +}
> +
> +static void kirkwood_cpufreq_set_cpu_state(unsigned int index)
> +{
> +	struct cpufreq_freqs freqs;
> +	unsigned int state = kirkwood_freq_table[index].index;
> +	unsigned long reg;
> +
> +	freqs.old = kirkwood_cpufreq_get_cpu_frequency(0);
> +	freqs.new = kirkwood_freq_table[index].frequency;
> +	freqs.cpu = 0; /* Kirkwood is UP */
> +
> +	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
> +
> +	dev_dbg(priv.dev, "Attempting to set frequency to %i KHz\n",
> +		kirkwood_freq_table[index].frequency);
> +	dev_dbg(priv.dev, "old frequency was %i KHz\n",
> +		kirkwood_cpufreq_get_cpu_frequency(0));
> +
> +	if (freqs.old != freqs.new) {
> +		local_irq_disable();
> +
> +		/* Disable interrupts to the CPU */
> +		reg = readl_relaxed(priv.base);
> +		reg |= CPU_SW_INT_BLK;
> +		writel_relaxed(reg, priv.base);
> +
> +		switch (state) {
> +		case STATE_CPU_FREQ:
> +			clk_disable(priv.powersave_clk);
> +			break;
> +		case STATE_DDR_FREQ:
> +			clk_enable(priv.powersave_clk);
> +			break;
> +		}
> +
> +		/* Wait-for-Interrupt, while the hardware changes frequency */
> +		cpu_do_idle();
> +
> +		/* Enable interrupts to the CPU */
> +		reg = readl_relaxed(priv.base);
> +		reg &= ~CPU_SW_INT_BLK;
> +		writel_relaxed(reg, priv.base);
> +
> +		local_irq_enable();
> +	}
> +	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
> +};
> +
> +static int kirkwood_cpufreq_verify(struct cpufreq_policy *policy)
> +{
> +	return cpufreq_frequency_table_verify(policy, kirkwood_freq_table);
> +}
> +
> +static int kirkwood_cpufreq_target(struct cpufreq_policy *policy,
> +			    unsigned int target_freq,
> +			    unsigned int relation)
> +{
> +	unsigned int index = 0;
> +
> +	if (cpufreq_frequency_table_target(policy, kirkwood_freq_table,
> +				target_freq, relation, &index))
> +		return -EINVAL;
> +
> +	kirkwood_cpufreq_set_cpu_state(index);
> +
> +	return 0;
> +}
> +
> +/* Module init and exit code */
> +static int kirkwood_cpufreq_cpu_init(struct cpufreq_policy *policy)
> +{
> +	int result;
> +
> +	/* cpuinfo and default policy values */
> +	policy->cpuinfo.transition_latency = 5000; /* 5uS */
> +	policy->cur = kirkwood_cpufreq_get_cpu_frequency(0);
> +
> +	result = cpufreq_frequency_table_cpuinfo(policy, kirkwood_freq_table);
> +	if (result)
> +		return result;
> +
> +	cpufreq_frequency_table_get_attr(kirkwood_freq_table, policy->cpu);
> +
> +	return 0;
> +}
> +
> +static int kirkwood_cpufreq_cpu_exit(struct cpufreq_policy *policy)
> +{
> +	cpufreq_frequency_table_put_attr(policy->cpu);
> +	return 0;
> +}
> +
> +static struct freq_attr *kirkwood_cpufreq_attr[] = {
> +	&cpufreq_freq_attr_scaling_available_freqs,
> +	NULL,
> +};
> +
> +static struct cpufreq_driver kirkwood_cpufreq_driver = {
> +	.get	= kirkwood_cpufreq_get_cpu_frequency,
> +	.verify	= kirkwood_cpufreq_verify,
> +	.target	= kirkwood_cpufreq_target,
> +	.init	= kirkwood_cpufreq_cpu_init,
> +	.exit	= kirkwood_cpufreq_cpu_exit,
> +	.name	= "kirkwood-cpufreq",
> +	.owner	= THIS_MODULE,
> +	.attr	= kirkwood_cpufreq_attr,
> +};
> +
> +static int kirkwood_cpufreq_probe(struct platform_device *pdev)
> +{
> +	struct device_node *np_core = of_find_compatible_node(
> +		NULL, NULL, "marvell,kirkwood-core-clock");
> +	struct device_node *np_gating = of_find_compatible_node(
> +		NULL, NULL, "marvell,kirkwood-gating-clock");
> +	struct of_phandle_args clkspec;
> +	struct resource *res;
> +	int err;
> +
> +	if (!np_core || !np_gating) {
> +		if (np_core)
> +			of_node_put(np_core);
> +		if (np_gating)
> +			of_node_put(np_gating);
> +		return -ENODEV;
> +	}
> +	
> +	priv.dev = &pdev->dev;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		dev_err(&pdev->dev, "Cannot get memory resource\n");
> +		return -ENODEV;
> +	}
> +	priv.base = devm_request_and_ioremap(&pdev->dev, res);
> +	if (!priv.base) {
> +		dev_err(&pdev->dev, "Cannot ioremap\n");
> +		return -EADDRNOTAVAIL;
> +	}
> +
> +	clkspec.np = np_core;
> +	clkspec.args_count = 1;
> +	clkspec.args[0] = 1;
> +
> +	priv.cpu_clk = of_clk_get_from_provider(&clkspec);

Again, clk client is not really supposed to call this.  Having a node
in device tree consuming all the clocks you need and attaching the
node to pdev->dev.of_node will have devm_clk_get just work for you.
The node could reasonably be /cpus/cpu at 0.

Shawn

> +	if (IS_ERR(priv.cpu_clk)) {
> +		dev_err(priv.dev, "Unable to get cpuclk");
> +		return PTR_ERR(priv.cpu_clk);
> +	}
> +
> +	clk_prepare_enable(priv.cpu_clk);
> +	kirkwood_freq_table[0].frequency = clk_get_rate(priv.cpu_clk) / 1000;
> +
> +	clkspec.args[0] = 3;
> +	priv.ddr_clk = of_clk_get_from_provider(&clkspec);
> +	if (IS_ERR(priv.ddr_clk)) {
> +		dev_err(priv.dev, "Unable to get ddrclk");
> +		err = PTR_ERR(priv.ddr_clk);
> +		goto out_cpu;
> +	}
> +
> +	clk_prepare_enable(priv.ddr_clk);
> +	kirkwood_freq_table[1].frequency = clk_get_rate(priv.ddr_clk) / 1000;
> +
> +	clkspec.np = np_gating;
> +	clkspec.args[0] = 11;
> +	priv.powersave_clk = of_clk_get_from_provider(&clkspec);
> +	if (IS_ERR(priv.powersave_clk)) {
> +		dev_err(priv.dev, "Unable to get powersave");
> +		err = PTR_ERR(priv.powersave_clk);
> +		goto out_ddr;
> +	}
> +	clk_prepare(priv.powersave_clk);
> +
> +	of_node_put(np_core);
> +	np_core = NULL;
> +	of_node_put(np_gating);
> +	np_gating = NULL;
> +
> +	err = cpufreq_register_driver(&kirkwood_cpufreq_driver);
> +	if (!err)
> +		return 0;
> +
> +	dev_err(priv.dev, "Failed to register cpufreq driver");
> +
> +	clk_disable_unprepare(priv.powersave_clk);
> +out_ddr:
> +	clk_disable_unprepare(priv.ddr_clk);
> +out_cpu:
> +	clk_disable_unprepare(priv.cpu_clk);
> +	of_node_put(np_core);
> +	of_node_put(np_gating);
> +
> +	return err;
> +}
> +
> +static int kirkwood_cpufreq_remove(struct platform_device *pdev)
> +{
> +	cpufreq_unregister_driver(&kirkwood_cpufreq_driver);
> +
> +	clk_disable_unprepare(priv.powersave_clk);
> +	clk_disable_unprepare(priv.ddr_clk);
> +	clk_disable_unprepare(priv.cpu_clk);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver kirkwood_cpufreq_platform_driver = {
> +	.probe = kirkwood_cpufreq_probe,
> +	.remove = kirkwood_cpufreq_remove,
> +	.driver = {
> +		.name = "kirkwood-cpufreq",
> +		.owner = THIS_MODULE,
> +	},
> +};
> +
> +module_platform_driver(kirkwood_cpufreq_platform_driver);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch");
> +MODULE_DESCRIPTION("cpufreq driver for Marvell's kirkwood CPU");
> +MODULE_ALIAS("platform:kirkwood-cpufreq");
> -- 
> 1.7.10.4
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH v4 2/3] arm: kirkwood: Instantiate cpufreq driver

[Andrew Lunn]

Register a platform driver structure for the cpufreq driver.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Jason Cooper <jason@lakedaemon.net>
---

To be commited by: Jason Coope

 arch/arm/Kconfig                                  |    1 +
 arch/arm/mach-kirkwood/board-dt.c                 |    3 ++-
 arch/arm/mach-kirkwood/common.c                   |   23 +++++++++++++++++++++
 arch/arm/mach-kirkwood/common.h                   |    2 ++
 arch/arm/mach-kirkwood/include/mach/bridge-regs.h |    2 ++
 5 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 67874b8..830975b 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -543,6 +543,7 @@ config ARCH_DOVE
 
 config ARCH_KIRKWOOD
 	bool "Marvell Kirkwood"
+	select ARCH_HAS_CPUFREQ
 	select ARCH_REQUIRE_GPIOLIB
 	select CPU_FEROCEON
 	select GENERIC_CLOCKEVENTS
diff --git a/arch/arm/mach-kirkwood/board-dt.c b/arch/arm/mach-kirkwood/board-dt.c
index de4fd2b..fab541d 100644
--- a/arch/arm/mach-kirkwood/board-dt.c
+++ b/arch/arm/mach-kirkwood/board-dt.c
@@ -70,7 +70,6 @@ static void __init kirkwood_legacy_clk_init(void)
 	clkspec.args[0] = CGC_BIT_SDIO;
 	orion_clkdev_add(NULL, "mvsdio",
 			 of_clk_get_from_provider(&clkspec));
-
 }
 
 static void __init kirkwood_of_clk_init(void)
@@ -95,6 +94,8 @@ static void __init kirkwood_dt_init(void)
 
 	kirkwood_l2_init();
 
+	kirkwood_cpufreq_init();
+
 	/* Setup root of clk tree */
 	kirkwood_of_clk_init();
 
diff --git a/arch/arm/mach-kirkwood/common.c b/arch/arm/mach-kirkwood/common.c
index bac21a5..a3dc21c 100644
--- a/arch/arm/mach-kirkwood/common.c
+++ b/arch/arm/mach-kirkwood/common.c
@@ -584,6 +584,29 @@ void __init kirkwood_audio_init(void)
 }
 
 /*****************************************************************************
+ * CPU Frequency
+ ****************************************************************************/
+static struct resource kirkwood_cpufreq_resources[] = {
+	[0] = {
+		.start  = CPU_CONTROL_PHYS,
+		.end    = CPU_CONTROL_PHYS + 3,
+		.flags  = IORESOURCE_MEM,
+	},
+};
+
+static struct platform_device kirkwood_cpufreq_device = {
+	.name		= "kirkwood-cpufreq",
+	.id		= -1,
+	.num_resources	= ARRAY_SIZE(kirkwood_cpufreq_resources),
+	.resource	= kirkwood_cpufreq_resources,
+};
+
+void __init kirkwood_cpufreq_init(void)
+{
+	platform_device_register(&kirkwood_cpufreq_device);
+}
+
+/*****************************************************************************
  * General
  ****************************************************************************/
 /*
diff --git a/arch/arm/mach-kirkwood/common.h b/arch/arm/mach-kirkwood/common.h
index 5ffa57f..9ede04b 100644
--- a/arch/arm/mach-kirkwood/common.h
+++ b/arch/arm/mach-kirkwood/common.h
@@ -50,6 +50,8 @@ void kirkwood_nand_init(struct mtd_partition *parts, int nr_parts, int delay);
 void kirkwood_nand_init_rnb(struct mtd_partition *parts, int nr_parts,
 			    int (*dev_ready)(struct mtd_info *));
 void kirkwood_audio_init(void);
+void kirkwood_cpufreq_init(void);
+
 void kirkwood_restart(char, const char *);
 void kirkwood_clk_init(void);
 
diff --git a/arch/arm/mach-kirkwood/include/mach/bridge-regs.h b/arch/arm/mach-kirkwood/include/mach/bridge-regs.h
index 5c82b7d..d4cbe5e 100644
--- a/arch/arm/mach-kirkwood/include/mach/bridge-regs.h
+++ b/arch/arm/mach-kirkwood/include/mach/bridge-regs.h
@@ -17,6 +17,7 @@
 #define CPU_CONFIG_ERROR_PROP	0x00000004
 
 #define CPU_CONTROL		(BRIDGE_VIRT_BASE + 0x0104)
+#define CPU_CONTROL_PHYS	(BRIDGE_PHYS_BASE + 0x0104)
 #define CPU_RESET		0x00000002
 
 #define RSTOUTn_MASK		(BRIDGE_VIRT_BASE + 0x0108)
@@ -69,6 +70,7 @@
 #define CGC_RUNIT		(1 << 7)
 #define CGC_XOR0		(1 << 8)
 #define CGC_AUDIO		(1 << 9)
+#define CGC_POWERSAVE           (1 << 11)
 #define CGC_SATA0		(1 << 14)
 #define CGC_SATA1		(1 << 15)
 #define CGC_XOR1		(1 << 16)
-- 
1.7.10.4

[PATCH v4 3/3] arm: kirkwood: Enable cpufreq and ondemand on kirkwood_defconfig

[Andrew Lunn]

Now that we have a cpufreq driver for kirkwood, enable it in
kirkwood_defconfig and set the default governer to ondemand.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Jason Cooper <jason@lakedaemon.net>
---

To be commited by: Jason Coope

 arch/arm/configs/kirkwood_defconfig |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm/configs/kirkwood_defconfig b/arch/arm/configs/kirkwood_defconfig
index 93f3794..6ecb7de 100644
--- a/arch/arm/configs/kirkwood_defconfig
+++ b/arch/arm/configs/kirkwood_defconfig
@@ -55,6 +55,9 @@ CONFIG_AEABI=y
 # CONFIG_OABI_COMPAT is not set
 CONFIG_ZBOOT_ROM_TEXT=0x0
 CONFIG_ZBOOT_ROM_BSS=0x0
+CONFIG_CPU_FREQ=y
+CONFIG_CPU_FREQ_STAT_DETAILS=y
+CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
 CONFIG_CPU_IDLE=y
 CONFIG_NET=y
 CONFIG_PACKET=y
-- 
1.7.10.4

[PATCH 43 0/3] Kirkwoode cpufreq driver

[Viresh Kumar]

On 1 February 2013 20:01, Andrew Lunn <andrew@lunn.ch> wrote:
> This patchset adds a cpufreq driver for Marvell Kirkwood SoCs.
>
> The changes to kirkwood_defconfig enable it and set the default
> governor to ondemand.

Wow! [PATCH 43 0/3] :)
It looks you are adding v4 manually to every patch? If yes, you need to
use following:

git format-patch A..B --cover-letter --subject-prefix="PATCH V4"

[PATCH 43 0/3] Kirkwoode cpufreq driver

[Andrew Lunn]

On Fri, Feb 01, 2013 at 08:04:27PM +0530, Viresh Kumar wrote:
> On 1 February 2013 20:01, Andrew Lunn <andrew@lunn.ch> wrote:
> > This patchset adds a cpufreq driver for Marvell Kirkwood SoCs.
> >
> > The changes to kirkwood_defconfig enable it and set the default
> > governor to ondemand.
> 
> Wow! [PATCH 43 0/3] :)
> It looks you are adding v4 manually to every patch? 

No, I just edited the cover note. For the others i used --subject=...

    Andrew