diff options
Diffstat (limited to 'target/linux/ipq806x/patches-4.4')
2 files changed, 259 insertions, 0 deletions
diff --git a/target/linux/ipq806x/patches-4.4/169-OPP-Support-adjusting-OPP-voltages-at-runtime.patch b/target/linux/ipq806x/patches-4.4/169-OPP-Support-adjusting-OPP-voltages-at-runtime.patch new file mode 100644 index 0000000000..8f0afb504c --- /dev/null +++ b/target/linux/ipq806x/patches-4.4/169-OPP-Support-adjusting-OPP-voltages-at-runtime.patch @@ -0,0 +1,145 @@ +From 111139c943a082364fbbcd9e0cc94cd442481340 Mon Sep 17 00:00:00 2001 +From: Stephen Boyd <sboyd@codeaurora.org> +Date: Mon, 1 Jun 2015 18:47:56 -0700 +Subject: PM / OPP: Support adjusting OPP voltages at runtime + +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. + +Cc: Nishanth Menon <nm@ti.com> +Cc: Viresh Kumar <viresh.kumar@linaro.org> +Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> +Acked-by: Viresh Kumar <viresh.kumar@linaro.org> +--- + drivers/base/power/opp/core.c | 77 +++++++++++++++++++++++++++++++++++++++++++ + include/linux/pm_opp.h | 10 ++++++ + 2 files changed, 87 insertions(+) + +--- a/drivers/base/power/opp/core.c ++++ b/drivers/base/power/opp/core.c +@@ -1039,6 +1039,83 @@ unlock: + } + + /** ++ * 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 device_opp *dev_opp; ++ struct dev_pm_opp *new_opp, *tmp_opp, *opp = ERR_PTR(-ENODEV); ++ int r = 0; ++ ++ /* keep the node allocated */ ++ new_opp = kmalloc(sizeof(*new_opp), GFP_KERNEL); ++ if (!new_opp) ++ return -ENOMEM; ++ ++ mutex_lock(&dev_opp_list_lock); ++ ++ /* Find the device_opp */ ++ dev_opp = _find_device_opp(dev); ++ if (IS_ERR(dev_opp)) { ++ r = PTR_ERR(dev_opp); ++ dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r); ++ goto unlock; ++ } ++ ++ /* Do we have the frequency? */ ++ list_for_each_entry(tmp_opp, &dev_opp->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->u_volt == u_volt) ++ goto unlock; ++ /* copy the old data over */ ++ *new_opp = *opp; ++ ++ /* plug in new node */ ++ new_opp->u_volt = u_volt; ++ ++ list_replace_rcu(&opp->node, &new_opp->node); ++ mutex_unlock(&dev_opp_list_lock); ++ call_srcu(&dev_opp->srcu_head.srcu, &opp->rcu_head, _kfree_opp_rcu); ++ ++ /* Notify the change of the OPP */ ++ srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_ADJUST_VOLTAGE, ++ new_opp); ++ ++ return 0; ++ ++unlock: ++ mutex_unlock(&dev_opp_list_lock); ++ kfree(new_opp); ++ return r; ++} ++ ++/** + * dev_pm_opp_enable() - Enable a specific OPP + * @dev: device for which we do this operation + * @freq: OPP frequency to enable +--- a/include/linux/pm_opp.h ++++ b/include/linux/pm_opp.h +@@ -22,6 +22,7 @@ struct device; + + enum dev_pm_opp_event { + OPP_EVENT_ADD, OPP_EVENT_REMOVE, OPP_EVENT_ENABLE, OPP_EVENT_DISABLE, ++ OPP_EVENT_ADJUST_VOLTAGE, + }; + + #if defined(CONFIG_PM_OPP) +@@ -50,6 +51,9 @@ int dev_pm_opp_add(struct device *dev, u + unsigned long u_volt); + void dev_pm_opp_remove(struct device *dev, unsigned long freq); + ++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); +@@ -114,6 +118,12 @@ static inline void dev_pm_opp_remove(str + { + } + ++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; diff --git a/target/linux/ipq806x/patches-4.4/170-OPP-Allow-notifiers-to-call-dev_pm_opp_get_voltage-freq-RCU-free.patch b/target/linux/ipq806x/patches-4.4/170-OPP-Allow-notifiers-to-call-dev_pm_opp_get_voltage-freq-RCU-free.patch new file mode 100644 index 0000000000..7be47a3509 --- /dev/null +++ b/target/linux/ipq806x/patches-4.4/170-OPP-Allow-notifiers-to-call-dev_pm_opp_get_voltage-freq-RCU-free.patch @@ -0,0 +1,114 @@ +From d330eae026b4a73e77ca0422f5cae5207d80f738 Mon Sep 17 00:00:00 2001 +From: Stephen Boyd <sboyd@codeaurora.org> +Date: Mon, 1 Jun 2015 18:47:57 -0700 +Subject: OPP: Allow notifiers to call dev_pm_opp_get_{voltage, freq} RCU-free + +We pass the dev_pm_opp structure to OPP notifiers but the users +of the notifier need to surround calls to dev_pm_opp_get_*() with +RCU read locks to avoid lockdep warnings. The notifier is already +called with the dev_opp's srcu lock held, so it should be safe to +assume the devm_pm_opp structure is already protected inside the +notifier. Update the lockdep check for this. + +Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com> +Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> +--- + drivers/base/power/opp/core.c | 27 +++++++++++++++------------ + 1 file changed, 15 insertions(+), 12 deletions(-) + +--- a/drivers/base/power/opp/core.c ++++ b/drivers/base/power/opp/core.c +@@ -31,9 +31,10 @@ static LIST_HEAD(dev_opp_list); + /* Lock to allow exclusive modification to the device and opp lists */ + DEFINE_MUTEX(dev_opp_list_lock); + +-#define opp_rcu_lockdep_assert() \ ++#define opp_rcu_lockdep_assert(s) \ + do { \ + RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \ ++ !(s && srcu_read_lock_held(s)) && \ + !lockdep_is_held(&dev_opp_list_lock), \ + "Missing rcu_read_lock() or " \ + "dev_opp_list_lock protection"); \ +@@ -91,7 +92,7 @@ struct device_opp *_find_device_opp(stru + { + struct device_opp *dev_opp; + +- opp_rcu_lockdep_assert(); ++ opp_rcu_lockdep_assert(NULL); + + if (IS_ERR_OR_NULL(dev)) { + pr_err("%s: Invalid parameters\n", __func__); +@@ -125,10 +126,11 @@ unsigned long dev_pm_opp_get_voltage(str + struct dev_pm_opp *tmp_opp; + unsigned long v = 0; + +- opp_rcu_lockdep_assert(); ++ opp_rcu_lockdep_assert(&opp->dev_opp->srcu_head.srcu); + +- tmp_opp = rcu_dereference(opp); +- if (IS_ERR_OR_NULL(tmp_opp)) ++ tmp_opp = srcu_dereference_check(opp, &opp->dev_opp->srcu_head.srcu, ++ rcu_read_lock_held()); ++ if (IS_ERR_OR_NULL(tmp_opp) || !tmp_opp->available) + pr_err("%s: Invalid parameters\n", __func__); + else + v = tmp_opp->u_volt; +@@ -157,9 +159,10 @@ unsigned long dev_pm_opp_get_freq(struct + struct dev_pm_opp *tmp_opp; + unsigned long f = 0; + +- opp_rcu_lockdep_assert(); ++ opp_rcu_lockdep_assert(&opp->dev_opp->srcu_head.srcu); + +- tmp_opp = rcu_dereference(opp); ++ tmp_opp = srcu_dereference_check(opp, &opp->dev_opp->srcu_head.srcu, ++ rcu_read_lock_held()); + if (IS_ERR_OR_NULL(tmp_opp) || !tmp_opp->available) + pr_err("%s: Invalid parameters\n", __func__); + else +@@ -191,7 +194,7 @@ bool dev_pm_opp_is_turbo(struct dev_pm_o + { + struct dev_pm_opp *tmp_opp; + +- opp_rcu_lockdep_assert(); ++ opp_rcu_lockdep_assert(&opp->dev_opp->srcu_head.srcu); + + tmp_opp = rcu_dereference(opp); + if (IS_ERR_OR_NULL(tmp_opp) || !tmp_opp->available) { +@@ -246,7 +249,7 @@ struct dev_pm_opp *dev_pm_opp_get_suspen + { + struct device_opp *dev_opp; + +- opp_rcu_lockdep_assert(); ++ opp_rcu_lockdep_assert(NULL); + + dev_opp = _find_device_opp(dev); + if (IS_ERR(dev_opp) || !dev_opp->suspend_opp || +@@ -326,7 +329,7 @@ struct dev_pm_opp *dev_pm_opp_find_freq_ + struct device_opp *dev_opp; + struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE); + +- opp_rcu_lockdep_assert(); ++ opp_rcu_lockdep_assert(NULL); + + dev_opp = _find_device_opp(dev); + if (IS_ERR(dev_opp)) { +@@ -374,7 +377,7 @@ struct dev_pm_opp *dev_pm_opp_find_freq_ + struct device_opp *dev_opp; + struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE); + +- opp_rcu_lockdep_assert(); ++ opp_rcu_lockdep_assert(NULL); + + if (!dev || !freq) { + dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq); +@@ -424,7 +427,7 @@ struct dev_pm_opp *dev_pm_opp_find_freq_ + struct device_opp *dev_opp; + struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE); + +- opp_rcu_lockdep_assert(); ++ opp_rcu_lockdep_assert(NULL); + + if (!dev || !freq) { + dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq); |