From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Rafael J. Wysocki" <rjw@sisk.pl>
Subject: Re: [PATCH v3 2/3] PM / OPP: Initialize OPP table from device tree
Date: Thu, 16 Aug 2012 23:05:54 +0200
Message-ID: <201208162305.55114.rjw@sisk.pl>
References: <1344577046-14847-1-git-send-email-shawn.guo@linaro.org> <1344577046-14847-3-git-send-email-shawn.guo@linaro.org>
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Sender: cpufreq-owner@vger.kernel.org
To: Shawn Guo <shawn.guo@linaro.org>
Cc: cpufreq@vger.kernel.org, linux-pm@vger.kernel.org, Kevin Hilman <khilman@ti.com>, Nishanth Menon <nm@ti.com>, Shilimkar Santosh <santosh.shilimkar@ti.com>, Richard Zhao <richard.zhao@freescale.com>, Russell King - ARM Linux <linux@arm.linux.org.uk>, Mike Turquette <mturquette@linaro.org>, Mark Brown <broonie@opensource.wolfsonmicro.com>, Rob Herring <rob.herring@calxeda.com>, devicetree-discuss@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, Arnd Bergmann <arnd@arndb.de>
List-Id: devicetree@vger.kernel.org

On Friday, August 10, 2012, Shawn Guo wrote:
> With a lot of devices booting from device tree nowadays, it requires
> that OPP table can be initialized from device tree.  The patch adds
> a helper function of_init_opp_table together with a binding doc for
> that purpose.
> 
> Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

I need an ACK from whoever maintains the DT bindings for that.

Thanks,
Rafael


> ---
>  Documentation/devicetree/bindings/power/opp.txt |   25 ++++++++++++
>  drivers/base/power/opp.c                        |   47 +++++++++++++++++++++++
>  include/linux/opp.h                             |    8 ++++
>  3 files changed, 80 insertions(+), 0 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/power/opp.txt
> 
> diff --git a/Documentation/devicetree/bindings/power/opp.txt b/Documentation/devicetree/bindings/power/opp.txt
> new file mode 100644
> index 0000000..74499e5
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/power/opp.txt
> @@ -0,0 +1,25 @@
> +* Generic OPP Interface
> +
> +SoCs have a standard set of tuples consisting of frequency and
> +voltage pairs that the device will support per voltage domain. These
> +are called Operating Performance Points or OPPs.
> +
> +Properties:
> +- operating-points: An array of 2-tuples items, and each item consists
> +  of frequency and voltage like <freq-kHz vol-uV>.
> +	freq: clock frequency in kHz
> +	vol: voltage in microvolt
> +
> +Examples:
> +
> +cpu@0 {
> +	compatible = "arm,cortex-a9";
> +	reg = <0>;
> +	next-level-cache = <&L2>;
> +	operating-points = <
> +		/* kHz    uV */
> +		792000  1100000
> +		396000  950000
> +		198000  850000
> +	>;
> +};
> diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c
> index ac993ea..d946864 100644
> --- a/drivers/base/power/opp.c
> +++ b/drivers/base/power/opp.c
> @@ -22,6 +22,7 @@
>  #include <linux/rculist.h>
>  #include <linux/rcupdate.h>
>  #include <linux/opp.h>
> +#include <linux/of.h>
>  
>  /*
>   * Internal data structure organization with the OPP layer library is as
> @@ -674,3 +675,49 @@ struct srcu_notifier_head *opp_get_notifier(struct device *dev)
>  
>  	return &dev_opp->head;
>  }
> +
> +#ifdef CONFIG_OF
> +/**
> + * of_init_opp_table() - Initialize opp table from device tree
> + * @dev:	device pointer used to lookup device OPPs.
> + *
> + * Register the initial OPP table with the OPP library for given device.
> + */
> +int of_init_opp_table(struct device *dev)
> +{
> +	const struct property *prop;
> +	const __be32 *val;
> +	int nr;
> +
> +	prop = of_find_property(dev->of_node, "operating-points", NULL);
> +	if (!prop)
> +		return -ENODEV;
> +	if (!prop->value)
> +		return -ENODATA;
> +
> +	/*
> +	 * Each OPP is a set of tuples consisting of frequency and
> +	 * voltage like <freq-kHz vol-uV>.
> +	 */
> +	nr = prop->length / sizeof(u32);
> +	if (nr % 2) {
> +		dev_err(dev, "%s: Invalid OPP list\n", __func__);
> +		return -EINVAL;
> +	}
> +
> +	val = prop->value;
> +	while (nr) {
> +		unsigned long freq = be32_to_cpup(val++) * 1000;
> +		unsigned long volt = be32_to_cpup(val++);
> +
> +		if (opp_add(dev, freq, volt)) {
> +			dev_warn(dev, "%s: Failed to add OPP %ld\n",
> +				 __func__, freq);
> +			continue;
> +		}
> +		nr -= 2;
> +	}
> +
> +	return 0;
> +}
> +#endif
> diff --git a/include/linux/opp.h b/include/linux/opp.h
> index 2a4e5fa..214e0eb 100644
> --- a/include/linux/opp.h
> +++ b/include/linux/opp.h
> @@ -48,6 +48,14 @@ int opp_disable(struct device *dev, unsigned long freq);
>  
>  struct srcu_notifier_head *opp_get_notifier(struct device *dev);
>  
> +#ifdef CONFIG_OF
> +int of_init_opp_table(struct device *dev);
> +#else
> +static inline int of_init_opp_table(struct device *dev)
> +{
> +	return -EINVAL;
> +}
> +#endif /* CONFIG_OF */
>  #else
>  static inline unsigned long opp_get_voltage(struct opp *opp)
>  {
> 


From mboxrd@z Thu Jan  1 00:00:00 1970
From: rjw@sisk.pl (Rafael J. Wysocki)
Date: Thu, 16 Aug 2012 23:05:54 +0200
Subject: [PATCH v3 2/3] PM / OPP: Initialize OPP table from device tree
In-Reply-To: <1344577046-14847-3-git-send-email-shawn.guo@linaro.org>
References: <1344577046-14847-1-git-send-email-shawn.guo@linaro.org>
 <1344577046-14847-3-git-send-email-shawn.guo@linaro.org>
Message-ID: <201208162305.55114.rjw@sisk.pl>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Friday, August 10, 2012, Shawn Guo wrote:
> With a lot of devices booting from device tree nowadays, it requires
> that OPP table can be initialized from device tree.  The patch adds
> a helper function of_init_opp_table together with a binding doc for
> that purpose.
> 
> Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

I need an ACK from whoever maintains the DT bindings for that.

Thanks,
Rafael


> ---
>  Documentation/devicetree/bindings/power/opp.txt |   25 ++++++++++++
>  drivers/base/power/opp.c                        |   47 +++++++++++++++++++++++
>  include/linux/opp.h                             |    8 ++++
>  3 files changed, 80 insertions(+), 0 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/power/opp.txt
> 
> diff --git a/Documentation/devicetree/bindings/power/opp.txt b/Documentation/devicetree/bindings/power/opp.txt
> new file mode 100644
> index 0000000..74499e5
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/power/opp.txt
> @@ -0,0 +1,25 @@
> +* Generic OPP Interface
> +
> +SoCs have a standard set of tuples consisting of frequency and
> +voltage pairs that the device will support per voltage domain. These
> +are called Operating Performance Points or OPPs.
> +
> +Properties:
> +- operating-points: An array of 2-tuples items, and each item consists
> +  of frequency and voltage like <freq-kHz vol-uV>.
> +	freq: clock frequency in kHz
> +	vol: voltage in microvolt
> +
> +Examples:
> +
> +cpu at 0 {
> +	compatible = "arm,cortex-a9";
> +	reg = <0>;
> +	next-level-cache = <&L2>;
> +	operating-points = <
> +		/* kHz    uV */
> +		792000  1100000
> +		396000  950000
> +		198000  850000
> +	>;
> +};
> diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c
> index ac993ea..d946864 100644
> --- a/drivers/base/power/opp.c
> +++ b/drivers/base/power/opp.c
> @@ -22,6 +22,7 @@
>  #include <linux/rculist.h>
>  #include <linux/rcupdate.h>
>  #include <linux/opp.h>
> +#include <linux/of.h>
>  
>  /*
>   * Internal data structure organization with the OPP layer library is as
> @@ -674,3 +675,49 @@ struct srcu_notifier_head *opp_get_notifier(struct device *dev)
>  
>  	return &dev_opp->head;
>  }
> +
> +#ifdef CONFIG_OF
> +/**
> + * of_init_opp_table() - Initialize opp table from device tree
> + * @dev:	device pointer used to lookup device OPPs.
> + *
> + * Register the initial OPP table with the OPP library for given device.
> + */
> +int of_init_opp_table(struct device *dev)
> +{
> +	const struct property *prop;
> +	const __be32 *val;
> +	int nr;
> +
> +	prop = of_find_property(dev->of_node, "operating-points", NULL);
> +	if (!prop)
> +		return -ENODEV;
> +	if (!prop->value)
> +		return -ENODATA;
> +
> +	/*
> +	 * Each OPP is a set of tuples consisting of frequency and
> +	 * voltage like <freq-kHz vol-uV>.
> +	 */
> +	nr = prop->length / sizeof(u32);
> +	if (nr % 2) {
> +		dev_err(dev, "%s: Invalid OPP list\n", __func__);
> +		return -EINVAL;
> +	}
> +
> +	val = prop->value;
> +	while (nr) {
> +		unsigned long freq = be32_to_cpup(val++) * 1000;
> +		unsigned long volt = be32_to_cpup(val++);
> +
> +		if (opp_add(dev, freq, volt)) {
> +			dev_warn(dev, "%s: Failed to add OPP %ld\n",
> +				 __func__, freq);
> +			continue;
> +		}
> +		nr -= 2;
> +	}
> +
> +	return 0;
> +}
> +#endif
> diff --git a/include/linux/opp.h b/include/linux/opp.h
> index 2a4e5fa..214e0eb 100644
> --- a/include/linux/opp.h
> +++ b/include/linux/opp.h
> @@ -48,6 +48,14 @@ int opp_disable(struct device *dev, unsigned long freq);
>  
>  struct srcu_notifier_head *opp_get_notifier(struct device *dev);
>  
> +#ifdef CONFIG_OF
> +int of_init_opp_table(struct device *dev);
> +#else
> +static inline int of_init_opp_table(struct device *dev)
> +{
> +	return -EINVAL;
> +}
> +#endif /* CONFIG_OF */
>  #else
>  static inline unsigned long opp_get_voltage(struct opp *opp)
>  {
>