From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Guo Subject: [PATCH v3 2/3] PM / OPP: Initialize OPP table from device tree Date: Fri, 10 Aug 2012 13:37:24 +0800 Message-ID: <1344577046-14847-3-git-send-email-shawn.guo@linaro.org> References: <1344577046-14847-1-git-send-email-shawn.guo@linaro.org> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1344577046-14847-1-git-send-email-shawn.guo@linaro.org> Sender: cpufreq-owner@vger.kernel.org To: "Rafael J. Wysocki" Cc: cpufreq@vger.kernel.org, linux-pm@vger.kernel.org, Kevin Hilman , Nishanth Menon , Shilimkar Santosh , Richard Zhao , Russell King - ARM Linux , Mike Turquette , Mark Brown , Rob Herring , devicetree-discuss@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, Shawn Guo List-Id: devicetree@vger.kernel.org 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 --- 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: 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 #include #include +#include /* * 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 . + */ + 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) { -- 1.7.5.4 From mboxrd@z Thu Jan 1 00:00:00 1970 From: shawn.guo@linaro.org (Shawn Guo) Date: Fri, 10 Aug 2012 13:37:24 +0800 Subject: [PATCH v3 2/3] PM / OPP: Initialize OPP table from device tree In-Reply-To: <1344577046-14847-1-git-send-email-shawn.guo@linaro.org> References: <1344577046-14847-1-git-send-email-shawn.guo@linaro.org> Message-ID: <1344577046-14847-3-git-send-email-shawn.guo@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 --- 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: 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 #include #include +#include /* * 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 . + */ + 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) { -- 1.7.5.4