Hi all,
This patch set is a continuation of my previous work, which aimed to add Energy Model to all devices [1]. This series is a follow up for the patches which got merged to v5.9-rc1. It aims to change the thermal devfreq cooling and use the Energy Model instead of private power table and structures. The power model is now simplified, static power and dynamic power are removed. The new registration interface in the patch 3/5 helps to register devfreq cooling and the EM in one call. There is also small improvement, patch 2/5 is changing the way how thermal gets the device status (now uses a copy) and normalize the values. The last patch is here for consistency and will probably go through drm tree.
The patch set is based on current next-20201208, because it depends on EM API change which is queued in the pm/linux-next tree as v5.11 material.
changes: v3: - dropped direct check of device status and used just a copy of 'status'; a separate patch set will be proposed to address this issue - modified _normalize_load() and used 1024 scale to handle ms, us, ns - removed 'em_registered' and called em_dev_unregister_perf_domain() unconditionally, so the drivers will have to make sure the right order of all unregister calls to frameworks which might use EM; this call must be last one; a proper comment added - removed 'em' pointer from struct devfreq_cooling_device, 'dev->em_pd' is used - removed of_node_get/put(), since the code can handle it - removed dfc_em_get_requested_power() (as missed to do it in v2) - collected all Reviewed-by tags v2 [3]: - renamed freq_get_state() and related to perf_idx pattern as suggested by Ionela v1 [2]
Regards, Lukasz Luba
[1] https://lkml.org/lkml/2020/5/11/326 [2] https://lore.kernel.org/linux-pm/20200921122007.29610-1-lukasz.luba@arm.com/ [3] https://lore.kernel.org/linux-pm/20201118120358.17150-1-lukasz.luba@arm.com/
Lukasz Luba (5): thermal: devfreq_cooling: change tracing function and arguments thermal: devfreq_cooling: use a copy of device status thermal: devfreq_cooling: add new registration functions with Energy Model thermal: devfreq_cooling: remove old power model and use EM drm/panfrost: Register devfreq cooling and attempt to add Energy Model
drivers/gpu/drm/panfrost/panfrost_devfreq.c | 2 +- drivers/thermal/devfreq_cooling.c | 420 ++++++++++---------- include/linux/devfreq_cooling.h | 40 +- include/trace/events/thermal.h | 19 +- 4 files changed, 240 insertions(+), 241 deletions(-)
Prepare for deleting the static and dynamic power calculation and clean the trace function. These two fields are going to be removed in the next changes.
Reviewed-by: Ionela Voinescu ionela.voinescu@arm.com Reviewed-by: Steven Rostedt (VMware) rostedt@goodmis.org # for tracing code Signed-off-by: Lukasz Luba lukasz.luba@arm.com --- drivers/thermal/devfreq_cooling.c | 3 +-- include/trace/events/thermal.h | 19 +++++++++---------- 2 files changed, 10 insertions(+), 12 deletions(-)
diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c index dfab49a67252..659c0143c9f0 100644 --- a/drivers/thermal/devfreq_cooling.c +++ b/drivers/thermal/devfreq_cooling.c @@ -277,8 +277,7 @@ static int devfreq_cooling_get_requested_power(struct thermal_cooling_device *cd *power = dyn_power + static_power; }
- trace_thermal_power_devfreq_get_power(cdev, status, freq, dyn_power, - static_power, *power); + trace_thermal_power_devfreq_get_power(cdev, status, freq, *power);
return 0; fail: diff --git a/include/trace/events/thermal.h b/include/trace/events/thermal.h index 135e5421f003..8a5f04888abd 100644 --- a/include/trace/events/thermal.h +++ b/include/trace/events/thermal.h @@ -153,31 +153,30 @@ TRACE_EVENT(thermal_power_cpu_limit, TRACE_EVENT(thermal_power_devfreq_get_power, TP_PROTO(struct thermal_cooling_device *cdev, struct devfreq_dev_status *status, unsigned long freq, - u32 dynamic_power, u32 static_power, u32 power), + u32 power),
- TP_ARGS(cdev, status, freq, dynamic_power, static_power, power), + TP_ARGS(cdev, status, freq, power),
TP_STRUCT__entry( __string(type, cdev->type ) __field(unsigned long, freq ) - __field(u32, load ) - __field(u32, dynamic_power ) - __field(u32, static_power ) + __field(u32, busy_time) + __field(u32, total_time) __field(u32, power) ),
TP_fast_assign( __assign_str(type, cdev->type); __entry->freq = freq; - __entry->load = (100 * status->busy_time) / status->total_time; - __entry->dynamic_power = dynamic_power; - __entry->static_power = static_power; + __entry->busy_time = status->busy_time; + __entry->total_time = status->total_time; __entry->power = power; ),
- TP_printk("type=%s freq=%lu load=%u dynamic_power=%u static_power=%u power=%u", + TP_printk("type=%s freq=%lu load=%u power=%u", __get_str(type), __entry->freq, - __entry->load, __entry->dynamic_power, __entry->static_power, + __entry->total_time == 0 ? 0 : + (100 * __entry->busy_time) / __entry->total_time, __entry->power) );
Devfreq cooling needs to now the correct status of the device in order to operate. Devfreq framework can change the device status in the background. To mitigate issues make a copy of the status structure and use it for internal calculations.
In addition this patch adds normalization function, which also makes sure that whatever data comes from the device, the load will be in range from 1 to 1024.
Reviewed-by: Ionela Voinescu ionela.voinescu@arm.com Signed-off-by: Lukasz Luba lukasz.luba@arm.com --- drivers/thermal/devfreq_cooling.c | 47 ++++++++++++++++++++++++------- 1 file changed, 37 insertions(+), 10 deletions(-)
diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c index 659c0143c9f0..afcebadbad24 100644 --- a/drivers/thermal/devfreq_cooling.c +++ b/drivers/thermal/devfreq_cooling.c @@ -227,20 +227,39 @@ static inline unsigned long get_total_power(struct devfreq_cooling_device *dfc, voltage); }
+static void _normalize_load(struct devfreq_dev_status *status) +{ + if (status->total_time > 0xfffff) { + status->total_time >>= 10; + status->busy_time >>= 10; + } + + status->busy_time <<= 10; + status->busy_time /= status->total_time ? : 1; + + status->busy_time = status->busy_time ? : 1; + status->total_time = 1024; +}
static int devfreq_cooling_get_requested_power(struct thermal_cooling_device *cdev, u32 *power) { struct devfreq_cooling_device *dfc = cdev->devdata; struct devfreq *df = dfc->devfreq; - struct devfreq_dev_status *status = &df->last_status; + struct devfreq_dev_status status; unsigned long state; - unsigned long freq = status->current_frequency; + unsigned long freq; unsigned long voltage; u32 dyn_power = 0; u32 static_power = 0; int res;
+ mutex_lock(&df->lock); + status = df->last_status; + mutex_unlock(&df->lock); + + freq = status.current_frequency; + state = freq_get_state(dfc, freq); if (state == THERMAL_CSTATE_INVALID) { res = -EAGAIN; @@ -268,16 +287,18 @@ static int devfreq_cooling_get_requested_power(struct thermal_cooling_device *cd } else { dyn_power = dfc->power_table[state];
+ _normalize_load(&status); + /* Scale dynamic power for utilization */ - dyn_power *= status->busy_time; - dyn_power /= status->total_time; + dyn_power *= status.busy_time; + dyn_power >>= 10; /* Get static power */ static_power = get_static_power(dfc, freq);
*power = dyn_power + static_power; }
- trace_thermal_power_devfreq_get_power(cdev, status, freq, *power); + trace_thermal_power_devfreq_get_power(cdev, &status, freq, *power);
return 0; fail: @@ -309,14 +330,19 @@ static int devfreq_cooling_power2state(struct thermal_cooling_device *cdev, { struct devfreq_cooling_device *dfc = cdev->devdata; struct devfreq *df = dfc->devfreq; - struct devfreq_dev_status *status = &df->last_status; - unsigned long freq = status->current_frequency; - unsigned long busy_time; + struct devfreq_dev_status status; + unsigned long freq; s32 dyn_power; u32 static_power; s32 est_power; int i;
+ mutex_lock(&df->lock); + status = df->last_status; + mutex_unlock(&df->lock); + + freq = status.current_frequency; + if (dfc->power_ops->get_real_power) { /* Scale for resource utilization */ est_power = power * dfc->res_util; @@ -328,8 +354,9 @@ static int devfreq_cooling_power2state(struct thermal_cooling_device *cdev, dyn_power = dyn_power > 0 ? dyn_power : 0;
/* Scale dynamic power for utilization */ - busy_time = status->busy_time ?: 1; - est_power = (dyn_power * status->total_time) / busy_time; + _normalize_load(&status); + dyn_power <<= 10; + est_power = dyn_power / status.busy_time; }
/*
The Energy Model (EM) framework supports devices such as Devfreq. Create new registration functions which automatically register EM for the thermal devfreq_cooling devices. This patch prepares the code for coming changes which are going to replace old power model with the new EM.
Reviewed-by: Ionela Voinescu ionela.voinescu@arm.com Signed-off-by: Lukasz Luba lukasz.luba@arm.com --- drivers/thermal/devfreq_cooling.c | 83 ++++++++++++++++++++++++++++++- include/linux/devfreq_cooling.h | 23 +++++++++ 2 files changed, 105 insertions(+), 1 deletion(-)
diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c index afcebadbad24..655eb89d60be 100644 --- a/drivers/thermal/devfreq_cooling.c +++ b/drivers/thermal/devfreq_cooling.c @@ -576,22 +576,103 @@ struct thermal_cooling_device *devfreq_cooling_register(struct devfreq *df) } EXPORT_SYMBOL_GPL(devfreq_cooling_register);
+/** + * devfreq_cooling_em_register_power() - Register devfreq cooling device with + * power information and automatically register Energy Model (EM) + * @df: Pointer to devfreq device. + * @dfc_power: Pointer to devfreq_cooling_power. + * @em_cb: Callback functions providing the data of the EM + * + * Register a devfreq cooling device and automatically register EM. The + * available OPPs must be registered for the device. + * + * If @dfc_power is provided, the cooling device is registered with the + * power extensions. If @em_cb is provided it will be called for each OPP to + * calculate power value and cost. If @em_cb is not provided then simple Energy + * Model is going to be used, which requires "dynamic-power-coefficient" a + * devicetree property. To not break drivers which miss that DT property, + * the function won't bail out when the EM registration failed. The cooling + * device will be registered if everything else is OK. + */ +struct thermal_cooling_device * +devfreq_cooling_em_register_power(struct devfreq *df, + struct devfreq_cooling_power *dfc_power, + struct em_data_callback *em_cb) +{ + struct thermal_cooling_device *cdev; + struct device *dev; + int nr_opp, ret; + + if (IS_ERR_OR_NULL(df)) + return ERR_PTR(-EINVAL); + + dev = df->dev.parent; + + if (em_cb) { + nr_opp = dev_pm_opp_get_opp_count(dev); + if (nr_opp <= 0) { + dev_err(dev, "No valid OPPs found\n"); + return ERR_PTR(-EINVAL); + } + + ret = em_dev_register_perf_domain(dev, nr_opp, em_cb, NULL, true); + } else { + ret = dev_pm_opp_of_register_em(dev, NULL); + } + + if (ret) + dev_dbg(dev, "Unable to register EM for devfreq cooling device (%d)\n", + ret); + + cdev = of_devfreq_cooling_register_power(dev->of_node, df, dfc_power); + + if (IS_ERR_OR_NULL(cdev)) + em_dev_unregister_perf_domain(dev); + + return cdev; +} +EXPORT_SYMBOL_GPL(devfreq_cooling_em_register_power); + +/** + * devfreq_cooling_em_register() - Register devfreq cooling device together + * with Energy Model. + * @df: Pointer to devfreq device. + * @em_cb: Callback functions providing the data of the Energy Model + * + * This function attempts to register Energy Model for devfreq device and then + * register the devfreq cooling device. + */ +struct thermal_cooling_device * +devfreq_cooling_em_register(struct devfreq *df, struct em_data_callback *em_cb) +{ + return devfreq_cooling_em_register_power(df, NULL, em_cb); +} +EXPORT_SYMBOL_GPL(devfreq_cooling_em_register); + /** * devfreq_cooling_unregister() - Unregister devfreq cooling device. * @cdev: Pointer to devfreq cooling device to unregister. + * + * Unregisters devfreq cooling device and related Energy Model if it was + * present. */ void devfreq_cooling_unregister(struct thermal_cooling_device *cdev) { struct devfreq_cooling_device *dfc; + struct device *dev;
- if (!cdev) + if (IS_ERR_OR_NULL(cdev)) return;
dfc = cdev->devdata; + dev = dfc->devfreq->dev.parent;
thermal_cooling_device_unregister(dfc->cdev); ida_simple_remove(&devfreq_ida, dfc->id); dev_pm_qos_remove_request(&dfc->req_max_freq); + + em_dev_unregister_perf_domain(dev); + kfree(dfc->power_table); kfree(dfc->freq_table);
diff --git a/include/linux/devfreq_cooling.h b/include/linux/devfreq_cooling.h index 9df2dfca68dd..f8c9aeaa17f5 100644 --- a/include/linux/devfreq_cooling.h +++ b/include/linux/devfreq_cooling.h @@ -11,6 +11,7 @@ #define __DEVFREQ_COOLING_H__
#include <linux/devfreq.h> +#include <linux/energy_model.h> #include <linux/thermal.h>
@@ -65,6 +66,13 @@ struct thermal_cooling_device * of_devfreq_cooling_register(struct device_node *np, struct devfreq *df); struct thermal_cooling_device *devfreq_cooling_register(struct devfreq *df); void devfreq_cooling_unregister(struct thermal_cooling_device *dfc); +struct thermal_cooling_device * +devfreq_cooling_em_register_power(struct devfreq *df, + struct devfreq_cooling_power *dfc_power, + struct em_data_callback *em_cb); +struct thermal_cooling_device * +devfreq_cooling_em_register(struct devfreq *df, + struct em_data_callback *em_cb);
#else /* !CONFIG_DEVFREQ_THERMAL */
@@ -87,6 +95,21 @@ devfreq_cooling_register(struct devfreq *df) return ERR_PTR(-EINVAL); }
+static inline struct thermal_cooling_device * +devfreq_cooling_em_register_power(struct devfreq *df, + struct devfreq_cooling_power *dfc_power, + struct em_data_callback *em_cb) +{ + return ERR_PTR(-EINVAL); +} + +static inline struct thermal_cooling_device * +devfreq_cooling_em_register(struct devfreq *df, + struct em_data_callback *em_cb) +{ + return ERR_PTR(-EINVAL); +} + static inline void devfreq_cooling_unregister(struct thermal_cooling_device *dfc) {
Remove old power model and use new Energy Model to calculate the power budget. It drops static + dynamic power calculations and power table in order to use Energy Model performance domain data. This model should be easy to use and could find more users. It is also less complicated to setup the needed structures.
Reviewed-by: Ionela Voinescu ionela.voinescu@arm.com Signed-off-by: Lukasz Luba lukasz.luba@arm.com --- drivers/thermal/devfreq_cooling.c | 307 ++++++++++-------------------- include/linux/devfreq_cooling.h | 17 -- 2 files changed, 97 insertions(+), 227 deletions(-)
diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c index 655eb89d60be..57632c0d0cd9 100644 --- a/drivers/thermal/devfreq_cooling.c +++ b/drivers/thermal/devfreq_cooling.c @@ -33,20 +33,17 @@ static DEFINE_IDA(devfreq_ida); * @cdev: Pointer to associated thermal cooling device. * @devfreq: Pointer to associated devfreq device. * @cooling_state: Current cooling state. - * @power_table: Pointer to table with maximum power draw for each - * cooling state. State is the index into the table, and - * the power is in mW. * @freq_table: Pointer to a table with the frequencies sorted in descending * order. You can index the table by cooling device state - * @freq_table_size: Size of the @freq_table and @power_table - * @power_ops: Pointer to devfreq_cooling_power, used to generate the - * @power_table. + * @max_state: It is the last index, that is, one less than the number of the + * OPPs + * @power_ops: Pointer to devfreq_cooling_power, a more precised model. * @res_util: Resource utilization scaling factor for the power. * It is multiplied by 100 to minimize the error. It is used * for estimation of the power budget instead of using - * 'utilization' (which is 'busy_time / 'total_time'). - * The 'res_util' range is from 100 to (power_table[state] * 100) - * for the corresponding 'state'. + * 'utilization' (which is 'busy_time' / 'total_time'). + * The 'res_util' range is from 100 to power * 100 for the + * corresponding 'state'. * @capped_state: index to cooling state with in dynamic power budget * @req_max_freq: PM QoS request for limiting the maximum frequency * of the devfreq device. @@ -56,9 +53,8 @@ struct devfreq_cooling_device { struct thermal_cooling_device *cdev; struct devfreq *devfreq; unsigned long cooling_state; - u32 *power_table; u32 *freq_table; - size_t freq_table_size; + size_t max_state; struct devfreq_cooling_power *power_ops; u32 res_util; int capped_state; @@ -70,7 +66,7 @@ static int devfreq_cooling_get_max_state(struct thermal_cooling_device *cdev, { struct devfreq_cooling_device *dfc = cdev->devdata;
- *state = dfc->freq_table_size - 1; + *state = dfc->max_state;
return 0; } @@ -92,16 +88,22 @@ static int devfreq_cooling_set_cur_state(struct thermal_cooling_device *cdev, struct devfreq *df = dfc->devfreq; struct device *dev = df->dev.parent; unsigned long freq; + int perf_idx;
if (state == dfc->cooling_state) return 0;
dev_dbg(dev, "Setting cooling state %lu\n", state);
- if (state >= dfc->freq_table_size) + if (state > dfc->max_state) return -EINVAL;
- freq = dfc->freq_table[state]; + if (dev->em_pd) { + perf_idx = dfc->max_state - state; + freq = dev->em_pd->table[perf_idx].frequency * 1000; + } else { + freq = dfc->freq_table[state]; + }
dev_pm_qos_update_request(&dfc->req_max_freq, DIV_ROUND_UP(freq, HZ_PER_KHZ)); @@ -112,24 +114,23 @@ static int devfreq_cooling_set_cur_state(struct thermal_cooling_device *cdev, }
/** - * freq_get_state() - get the cooling state corresponding to a frequency - * @dfc: Pointer to devfreq cooling device - * @freq: frequency in Hz + * get_perf_idx() - get the performance index corresponding to a frequency + * @em_pd: Pointer to device's Energy Model + * @freq: frequency in kHz * - * Return: the cooling state associated with the @freq, or - * THERMAL_CSTATE_INVALID if it wasn't found. + * Return: the performance index associated with the @freq, or + * -EINVAL if it wasn't found. */ -static unsigned long -freq_get_state(struct devfreq_cooling_device *dfc, unsigned long freq) +static int get_perf_idx(struct em_perf_domain *em_pd, unsigned long freq) { int i;
- for (i = 0; i < dfc->freq_table_size; i++) { - if (dfc->freq_table[i] == freq) + for (i = 0; i < em_pd->nr_perf_states; i++) { + if (em_pd->table[i].frequency == freq) return i; }
- return THERMAL_CSTATE_INVALID; + return -EINVAL; }
static unsigned long get_voltage(struct devfreq *df, unsigned long freq) @@ -160,73 +161,6 @@ static unsigned long get_voltage(struct devfreq *df, unsigned long freq) return voltage; }
-/** - * get_static_power() - calculate the static power - * @dfc: Pointer to devfreq cooling device - * @freq: Frequency in Hz - * - * Calculate the static power in milliwatts using the supplied - * get_static_power(). The current voltage is calculated using the - * OPP library. If no get_static_power() was supplied, assume the - * static power is negligible. - */ -static unsigned long -get_static_power(struct devfreq_cooling_device *dfc, unsigned long freq) -{ - struct devfreq *df = dfc->devfreq; - unsigned long voltage; - - if (!dfc->power_ops->get_static_power) - return 0; - - voltage = get_voltage(df, freq); - - if (voltage == 0) - return 0; - - return dfc->power_ops->get_static_power(df, voltage); -} - -/** - * get_dynamic_power - calculate the dynamic power - * @dfc: Pointer to devfreq cooling device - * @freq: Frequency in Hz - * @voltage: Voltage in millivolts - * - * Calculate the dynamic power in milliwatts consumed by the device at - * frequency @freq and voltage @voltage. If the get_dynamic_power() - * was supplied as part of the devfreq_cooling_power struct, then that - * function is used. Otherwise, a simple power model (Pdyn = Coeff * - * Voltage^2 * Frequency) is used. - */ -static unsigned long -get_dynamic_power(struct devfreq_cooling_device *dfc, unsigned long freq, - unsigned long voltage) -{ - u64 power; - u32 freq_mhz; - struct devfreq_cooling_power *dfc_power = dfc->power_ops; - - if (dfc_power->get_dynamic_power) - return dfc_power->get_dynamic_power(dfc->devfreq, freq, - voltage); - - freq_mhz = freq / 1000000; - power = (u64)dfc_power->dyn_power_coeff * freq_mhz * voltage * voltage; - do_div(power, 1000000000); - - return power; -} - - -static inline unsigned long get_total_power(struct devfreq_cooling_device *dfc, - unsigned long freq, - unsigned long voltage) -{ - return get_static_power(dfc, freq) + get_dynamic_power(dfc, freq, - voltage); -} - static void _normalize_load(struct devfreq_dev_status *status) { if (status->total_time > 0xfffff) { @@ -246,13 +180,12 @@ static int devfreq_cooling_get_requested_power(struct thermal_cooling_device *cd { struct devfreq_cooling_device *dfc = cdev->devdata; struct devfreq *df = dfc->devfreq; + struct device *dev = df->dev.parent; struct devfreq_dev_status status; unsigned long state; unsigned long freq; unsigned long voltage; - u32 dyn_power = 0; - u32 static_power = 0; - int res; + int res, perf_idx;
mutex_lock(&df->lock); status = df->last_status; @@ -260,13 +193,7 @@ static int devfreq_cooling_get_requested_power(struct thermal_cooling_device *cd
freq = status.current_frequency;
- state = freq_get_state(dfc, freq); - if (state == THERMAL_CSTATE_INVALID) { - res = -EAGAIN; - goto fail; - } - - if (dfc->power_ops->get_real_power) { + if (dfc->power_ops && dfc->power_ops->get_real_power) { voltage = get_voltage(df, freq); if (voltage == 0) { res = -EINVAL; @@ -276,7 +203,7 @@ static int devfreq_cooling_get_requested_power(struct thermal_cooling_device *cd res = dfc->power_ops->get_real_power(df, power, freq, voltage); if (!res) { state = dfc->capped_state; - dfc->res_util = dfc->power_table[state]; + dfc->res_util = dev->em_pd->table[state].power; dfc->res_util *= SCALE_ERROR_MITIGATION;
if (*power > 1) @@ -285,17 +212,19 @@ static int devfreq_cooling_get_requested_power(struct thermal_cooling_device *cd goto fail; } } else { - dyn_power = dfc->power_table[state]; + /* Energy Model frequencies are in kHz */ + perf_idx = get_perf_idx(dev->em_pd, freq / 1000); + if (perf_idx < 0) { + res = -EAGAIN; + goto fail; + }
_normalize_load(&status);
- /* Scale dynamic power for utilization */ - dyn_power *= status.busy_time; - dyn_power >>= 10; - /* Get static power */ - static_power = get_static_power(dfc, freq); - - *power = dyn_power + static_power; + /* Scale power for utilization */ + *power = dev->em_pd->table[perf_idx].power; + *power *= status.busy_time; + *power >>= 10; }
trace_thermal_power_devfreq_get_power(cdev, &status, freq, *power); @@ -308,20 +237,19 @@ static int devfreq_cooling_get_requested_power(struct thermal_cooling_device *cd }
static int devfreq_cooling_state2power(struct thermal_cooling_device *cdev, - unsigned long state, - u32 *power) + unsigned long state, u32 *power) { struct devfreq_cooling_device *dfc = cdev->devdata; - unsigned long freq; - u32 static_power; + struct devfreq *df = dfc->devfreq; + struct device *dev = df->dev.parent; + int perf_idx;
- if (state >= dfc->freq_table_size) + if (state > dfc->max_state) return -EINVAL;
- freq = dfc->freq_table[state]; - static_power = get_static_power(dfc, freq); + perf_idx = dfc->max_state - state; + *power = dev->em_pd->table[perf_idx].power;
- *power = dfc->power_table[state] + static_power; return 0; }
@@ -330,10 +258,9 @@ static int devfreq_cooling_power2state(struct thermal_cooling_device *cdev, { struct devfreq_cooling_device *dfc = cdev->devdata; struct devfreq *df = dfc->devfreq; + struct device *dev = df->dev.parent; struct devfreq_dev_status status; unsigned long freq; - s32 dyn_power; - u32 static_power; s32 est_power; int i;
@@ -343,32 +270,28 @@ static int devfreq_cooling_power2state(struct thermal_cooling_device *cdev,
freq = status.current_frequency;
- if (dfc->power_ops->get_real_power) { + if (dfc->power_ops && dfc->power_ops->get_real_power) { /* Scale for resource utilization */ est_power = power * dfc->res_util; est_power /= SCALE_ERROR_MITIGATION; } else { - static_power = get_static_power(dfc, freq); - - dyn_power = power - static_power; - dyn_power = dyn_power > 0 ? dyn_power : 0; - /* Scale dynamic power for utilization */ _normalize_load(&status); - dyn_power <<= 10; - est_power = dyn_power / status.busy_time; + est_power = power << 10; + est_power /= status.busy_time; }
/* * Find the first cooling state that is within the power - * budget for dynamic power. + * budget. The EM power table is sorted ascending. */ - for (i = 0; i < dfc->freq_table_size - 1; i++) - if (est_power >= dfc->power_table[i]) + for (i = dfc->max_state; i > 0; i--) + if (est_power >= dev->em_pd->table[i].power) break;
- *state = i; - dfc->capped_state = i; + *state = dfc->max_state - i; + dfc->capped_state = *state; + trace_thermal_power_devfreq_limit(cdev, freq, *state, power); return 0; } @@ -380,91 +303,43 @@ static struct thermal_cooling_device_ops devfreq_cooling_ops = { };
/** - * devfreq_cooling_gen_tables() - Generate power and freq tables. - * @dfc: Pointer to devfreq cooling device. - * - * Generate power and frequency tables: the power table hold the - * device's maximum power usage at each cooling state (OPP). The - * static and dynamic power using the appropriate voltage and - * frequency for the state, is acquired from the struct - * devfreq_cooling_power, and summed to make the maximum power draw. - * - * The frequency table holds the frequencies in descending order. - * That way its indexed by cooling device state. + * devfreq_cooling_gen_tables() - Generate frequency table. + * @dfc: Pointer to devfreq cooling device. + * @num_opps: Number of OPPs * - * The tables are malloced, and pointers put in dfc. They must be - * freed when unregistering the devfreq cooling device. + * Generate frequency table which holds the frequencies in descending + * order. That way its indexed by cooling device state. This is for + * compatibility with drivers which do not register Energy Model. * * Return: 0 on success, negative error code on failure. */ -static int devfreq_cooling_gen_tables(struct devfreq_cooling_device *dfc) +static int devfreq_cooling_gen_tables(struct devfreq_cooling_device *dfc, + int num_opps) { struct devfreq *df = dfc->devfreq; struct device *dev = df->dev.parent; - int ret, num_opps; unsigned long freq; - u32 *power_table = NULL; - u32 *freq_table; int i;
- num_opps = dev_pm_opp_get_opp_count(dev); - - if (dfc->power_ops) { - power_table = kcalloc(num_opps, sizeof(*power_table), - GFP_KERNEL); - if (!power_table) - return -ENOMEM; - } - - freq_table = kcalloc(num_opps, sizeof(*freq_table), + dfc->freq_table = kcalloc(num_opps, sizeof(*dfc->freq_table), GFP_KERNEL); - if (!freq_table) { - ret = -ENOMEM; - goto free_power_table; - } + if (!dfc->freq_table) + return -ENOMEM;
for (i = 0, freq = ULONG_MAX; i < num_opps; i++, freq--) { - unsigned long power, voltage; struct dev_pm_opp *opp;
opp = dev_pm_opp_find_freq_floor(dev, &freq); if (IS_ERR(opp)) { - ret = PTR_ERR(opp); - goto free_tables; + kfree(dfc->freq_table); + return PTR_ERR(opp); }
- voltage = dev_pm_opp_get_voltage(opp) / 1000; /* mV */ dev_pm_opp_put(opp); - - if (dfc->power_ops) { - if (dfc->power_ops->get_real_power) - power = get_total_power(dfc, freq, voltage); - else - power = get_dynamic_power(dfc, freq, voltage); - - dev_dbg(dev, "Power table: %lu MHz @ %lu mV: %lu = %lu mW\n", - freq / 1000000, voltage, power, power); - - power_table[i] = power; - } - - freq_table[i] = freq; + dfc->freq_table[i] = freq; }
- if (dfc->power_ops) - dfc->power_table = power_table; - - dfc->freq_table = freq_table; - dfc->freq_table_size = num_opps; - return 0; - -free_tables: - kfree(freq_table); -free_power_table: - kfree(power_table); - - return ret; }
/** @@ -487,9 +362,10 @@ of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df, struct devfreq_cooling_power *dfc_power) { struct thermal_cooling_device *cdev; + struct device *dev = df->dev.parent; struct devfreq_cooling_device *dfc; char dev_name[THERMAL_NAME_LENGTH]; - int err; + int err, num_opps;
dfc = kzalloc(sizeof(*dfc), GFP_KERNEL); if (!dfc) @@ -497,28 +373,44 @@ of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df,
dfc->devfreq = df;
- if (dfc_power) { - dfc->power_ops = dfc_power; - + if (dev->em_pd) { devfreq_cooling_ops.get_requested_power = devfreq_cooling_get_requested_power; devfreq_cooling_ops.state2power = devfreq_cooling_state2power; devfreq_cooling_ops.power2state = devfreq_cooling_power2state; + + dfc->power_ops = dfc_power; + + num_opps = em_pd_nr_perf_states(dev->em_pd); + } else { + /* Backward compatibility for drivers which do not use IPA */ + dev_dbg(dev, "missing EM for cooling device\n"); + + num_opps = dev_pm_opp_get_opp_count(dev); + + err = devfreq_cooling_gen_tables(dfc, num_opps); + if (err) + goto free_dfc; }
- err = devfreq_cooling_gen_tables(dfc); - if (err) + if (num_opps <= 0) { + err = -EINVAL; goto free_dfc; + } + + /* max_state is an index, not a counter */ + dfc->max_state = num_opps - 1;
- err = dev_pm_qos_add_request(df->dev.parent, &dfc->req_max_freq, + err = dev_pm_qos_add_request(dev, &dfc->req_max_freq, DEV_PM_QOS_MAX_FREQUENCY, PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE); if (err < 0) - goto free_tables; + goto free_table;
err = ida_simple_get(&devfreq_ida, 0, 0, GFP_KERNEL); if (err < 0) goto remove_qos_req; + dfc->id = err;
snprintf(dev_name, sizeof(dev_name), "thermal-devfreq-%d", dfc->id); @@ -527,7 +419,7 @@ of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df, &devfreq_cooling_ops); if (IS_ERR(cdev)) { err = PTR_ERR(cdev); - dev_err(df->dev.parent, + dev_err(dev, "Failed to register devfreq cooling device (%d)\n", err); goto release_ida; @@ -539,12 +431,9 @@ of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df,
release_ida: ida_simple_remove(&devfreq_ida, dfc->id); - remove_qos_req: dev_pm_qos_remove_request(&dfc->req_max_freq); - -free_tables: - kfree(dfc->power_table); +free_table: kfree(dfc->freq_table); free_dfc: kfree(dfc); @@ -673,9 +562,7 @@ void devfreq_cooling_unregister(struct thermal_cooling_device *cdev)
em_dev_unregister_perf_domain(dev);
- kfree(dfc->power_table); kfree(dfc->freq_table); - kfree(dfc); } EXPORT_SYMBOL_GPL(devfreq_cooling_unregister); diff --git a/include/linux/devfreq_cooling.h b/include/linux/devfreq_cooling.h index f8c9aeaa17f5..d0e801f4d725 100644 --- a/include/linux/devfreq_cooling.h +++ b/include/linux/devfreq_cooling.h @@ -17,17 +17,6 @@
/** * struct devfreq_cooling_power - Devfreq cooling power ops - * @get_static_power: Take voltage, in mV, and return the static power - * in mW. If NULL, the static power is assumed - * to be 0. - * @get_dynamic_power: Take voltage, in mV, and frequency, in HZ, and - * return the dynamic power draw in mW. If NULL, - * a simple power model is used. - * @dyn_power_coeff: Coefficient for the simple dynamic power model in - * mW/(MHz mV mV). - * If get_dynamic_power() is NULL, then the - * dynamic power is calculated as - * @dyn_power_coeff * frequency * voltage^2 * @get_real_power: When this is set, the framework uses it to ask the * device driver for the actual power. * Some devices have more sophisticated methods @@ -47,14 +36,8 @@ * max total (static + dynamic) power value for each OPP. */ struct devfreq_cooling_power { - unsigned long (*get_static_power)(struct devfreq *devfreq, - unsigned long voltage); - unsigned long (*get_dynamic_power)(struct devfreq *devfreq, - unsigned long freq, - unsigned long voltage); int (*get_real_power)(struct devfreq *df, u32 *power, unsigned long freq, unsigned long voltage); - unsigned long dyn_power_coeff; };
#ifdef CONFIG_DEVFREQ_THERMAL
Register devfreq cooling device and attempt to register Energy Model. This will add the devfreq device to the Energy Model framework. It will create a dedicated and unified data structures used i.e. in thermal framework. The last NULL parameter indicates that the power model is simplified and created based on DT 'dynamic-power-coefficient', voltage and frequency.
Reviewed-by: Steven Price steven.price@arm.com Reviewed-by: Alyssa Rosenzweig alyssa.rosenzweig@collabora.com Signed-off-by: Lukasz Luba lukasz.luba@arm.com --- drivers/gpu/drm/panfrost/panfrost_devfreq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.c b/drivers/gpu/drm/panfrost/panfrost_devfreq.c index 78e9d82f7318..f44d28fad085 100644 --- a/drivers/gpu/drm/panfrost/panfrost_devfreq.c +++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.c @@ -138,7 +138,7 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev) } pfdevfreq->devfreq = devfreq;
- cooling = of_devfreq_cooling_register(dev->of_node, devfreq); + cooling = devfreq_cooling_em_register(devfreq, NULL); if (IS_ERR(cooling)) DRM_DEV_INFO(dev, "Failed to register cooling device\n"); else
Hi Daniel,
On 12/9/20 10:30 AM, Lukasz Luba wrote:
Hi all,
This patch set is a continuation of my previous work, which aimed to add Energy Model to all devices [1]. This series is a follow up for the patches which got merged to v5.9-rc1. It aims to change the thermal devfreq cooling and use the Energy Model instead of private power table and structures. The power model is now simplified, static power and dynamic power are removed. The new registration interface in the patch 3/5 helps to register devfreq cooling and the EM in one call. There is also small improvement, patch 2/5 is changing the way how thermal gets the device status (now uses a copy) and normalize the values. The last patch is here for consistency and will probably go through drm tree.
The patch set is based on current next-20201208, because it depends on EM API change which is queued in the pm/linux-next tree as v5.11 material.
changes: v3:
- dropped direct check of device status and used just a copy of 'status'; a separate patch set will be proposed to address this issue
- modified _normalize_load() and used 1024 scale to handle ms, us, ns
- removed 'em_registered' and called em_dev_unregister_perf_domain() unconditionally, so the drivers will have to make sure the right order of all unregister calls to frameworks which might use EM; this call must be last one; a proper comment added
- removed 'em' pointer from struct devfreq_cooling_device, 'dev->em_pd' is used
- removed of_node_get/put(), since the code can handle it
- removed dfc_em_get_requested_power() (as missed to do it in v2)
- collected all Reviewed-by tags
v2 [3]:
- renamed freq_get_state() and related to perf_idx pattern as suggested by Ionela
v1 [2]
Regards, Lukasz Luba
[1] https://lkml.org/lkml/2020/5/11/326 [2] https://lore.kernel.org/linux-pm/20200921122007.29610-1-lukasz.luba@arm.com/ [3] https://lore.kernel.org/linux-pm/20201118120358.17150-1-lukasz.luba@arm.com/
Lukasz Luba (5): thermal: devfreq_cooling: change tracing function and arguments thermal: devfreq_cooling: use a copy of device status thermal: devfreq_cooling: add new registration functions with Energy Model thermal: devfreq_cooling: remove old power model and use EM drm/panfrost: Register devfreq cooling and attempt to add Energy Model
drivers/gpu/drm/panfrost/panfrost_devfreq.c | 2 +- drivers/thermal/devfreq_cooling.c | 420 ++++++++++---------- include/linux/devfreq_cooling.h | 40 +- include/trace/events/thermal.h | 19 +- 4 files changed, 240 insertions(+), 241 deletions(-)
If you consider to take it, please don't. I am going to send a v4 which does not have this em_dev_register_perf_domain() dependency due to API change. Then it could go via your thermal tree without issues.
It will be a small change in the patch 3/5, which will simplify registration function (use only dev_pm_opp_of_register_em()) and also instead of two registration function, have only one (which was also suggested by Ionela during review).
Regards, Lukasz
dri-devel@lists.freedesktop.org
-
Lukasz Luba