Re: [PATCH] devfreq: Register devfreq as a cooling device

Hi Daniel,

As Lukasz's comment, actually some devfreq devices like memory bus might not affect the thermal critically. In the mainline, there are four types devfreq as following: 1. GPU 2. UFS Storage 3. DMC (Memory Controller) 4. Memory bus like AMBA AXI

I think that you can specify this devfreq device will be used for cooling device by editing the devfreq_dev_profile structure.

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index bf3047896e41..77966a17d03f 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -935,6 +935,13 @@ struct devfreq *devfreq_add_device(struct device *dev,

mutex_unlock(&devfreq_list_lock);

+ if (devfreq->profile->is_cooling_device) { + devfreq->cdev = devfreq_cooling_em_register(devfreq, NULL); + if (IS_ERR(devfreq->cdev)) + dev_info(dev, + "Failed to register devfreq cooling device\n"); + } + return devfreq;

err_init: diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h index 26ea0850be9b..26dc69f1047b 100644 --- a/include/linux/devfreq.h +++ b/include/linux/devfreq.h @@ -103,6 +103,7 @@ struct devfreq_dev_profile { unsigned long initial_freq; unsigned int polling_ms; enum devfreq_timer timer; + bool is_cooling_device;

int (*target)(struct device *dev, unsigned long *freq, u32 flags); int (*get_dev_status)(struct device *dev,

Thanks Chanwoo Choi

On 21. 3. 4. 오후 9:50, Daniel Lezcano wrote:

Currently the default behavior is to manually having the devfreq backend to register themselves as a devfreq cooling device.

There are no so many and actually it makes more sense to register the devfreq device when adding it.

Consequently, every devfreq becomes a cooling device like cpufreq is.

Having a devfreq being registered as a cooling device can not mitigate a thermal zone if it is not bound to this one. Thus, the current configurations are not impacted by this change.

Signed-off-by: Daniel Lezcano daniel.lezcano@linaro.org

drivers/devfreq/devfreq.c | 8 ++++++++ drivers/gpu/drm/lima/lima_devfreq.c | 13 ------------- drivers/gpu/drm/lima/lima_devfreq.h | 2 -- drivers/gpu/drm/msm/msm_gpu.c | 11 ----------- drivers/gpu/drm/msm/msm_gpu.h | 2 -- drivers/gpu/drm/panfrost/panfrost_devfreq.c | 13 ------------- include/linux/devfreq.h | 3 +++ 7 files changed, 11 insertions(+), 41 deletions(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index b6d63f02d293..19149b31b000 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -11,6 +11,7 @@ #include <linux/kmod.h> #include <linux/sched.h> #include <linux/debugfs.h> +#include <linux/devfreq_cooling.h> #include <linux/errno.h> #include <linux/err.h> #include <linux/init.h> @@ -26,6 +27,7 @@ #include <linux/hrtimer.h> #include <linux/of.h> #include <linux/pm_qos.h> +#include <linux/thermal.h> #include <linux/units.h> #include "governor.h"

@@ -935,6 +937,10 @@ struct devfreq *devfreq_add_device(struct device *dev,

mutex_unlock(&devfreq_list_lock);

• devfreq->cdev = devfreq_cooling_em_register(devfreq, NULL);

• if (IS_ERR(devfreq->cdev))

• dev_info(dev, "Failed to register devfreq cooling device\n");
  

• return devfreq;

  err_init:

@@ -960,6 +966,8 @@ int devfreq_remove_device(struct devfreq *devfreq) if (!devfreq) return -EINVAL;

• thermal_cooling_device_unregister(devfreq->cdev);
• if (devfreq->governor) { devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_STOP, NULL);

diff --git a/drivers/gpu/drm/lima/lima_devfreq.c b/drivers/gpu/drm/lima/lima_devfreq.c index 5686ad4aaf7c..a696eff1642c 100644 --- a/drivers/gpu/drm/lima/lima_devfreq.c +++ b/drivers/gpu/drm/lima/lima_devfreq.c @@ -7,7 +7,6 @@ */ #include <linux/clk.h> #include <linux/devfreq.h> -#include <linux/devfreq_cooling.h> #include <linux/device.h> #include <linux/platform_device.h> #include <linux/pm_opp.h> @@ -90,11 +89,6 @@ void lima_devfreq_fini(struct lima_device *ldev) { struct lima_devfreq *devfreq = &ldev->devfreq;

• if (devfreq->cooling) {

• devfreq_cooling_unregister(devfreq->cooling);
  

• devfreq->cooling = NULL;
  

• }
• if (devfreq->devfreq) { devm_devfreq_remove_device(ldev->dev, devfreq->devfreq); devfreq->devfreq = NULL;

@@ -110,7 +104,6 @@ void lima_devfreq_fini(struct lima_device *ldev)

int lima_devfreq_init(struct lima_device *ldev) {

• struct thermal_cooling_device *cooling; struct device *dev = ldev->dev; struct opp_table *opp_table; struct devfreq *devfreq;

@@ -173,12 +166,6 @@ int lima_devfreq_init(struct lima_device *ldev)

ldevfreq->devfreq = devfreq;

• cooling = of_devfreq_cooling_register(dev->of_node, devfreq);

• if (IS_ERR(cooling))

• dev_info(dev, "Failed to register cooling device\n");
  

• else

• ldevfreq->cooling = cooling;
  

• return 0;

  err_fini:

diff --git a/drivers/gpu/drm/lima/lima_devfreq.h b/drivers/gpu/drm/lima/lima_devfreq.h index 2d9b3008ce77..c43a2069e5d3 100644 --- a/drivers/gpu/drm/lima/lima_devfreq.h +++ b/drivers/gpu/drm/lima/lima_devfreq.h @@ -9,7 +9,6 @@

struct devfreq; struct opp_table; -struct thermal_cooling_device;

struct lima_device;

@@ -17,7 +16,6 @@ struct lima_devfreq { struct devfreq *devfreq; struct opp_table *clkname_opp_table; struct opp_table *regulators_opp_table;

• struct thermal_cooling_device *cooling;

  ktime_t busy_time; ktime_t idle_time;

diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c index ab7c167b0623..d7f80ebfe9df 100644 --- a/drivers/gpu/drm/msm/msm_gpu.c +++ b/drivers/gpu/drm/msm/msm_gpu.c @@ -14,7 +14,6 @@ #include <generated/utsrelease.h> #include <linux/string_helpers.h> #include <linux/devfreq.h> -#include <linux/devfreq_cooling.h> #include <linux/devcoredump.h> #include <linux/sched/task.h>

@@ -112,14 +111,6 @@ static void msm_devfreq_init(struct msm_gpu *gpu) }

devfreq_suspend_device(gpu->devfreq.devfreq);

• gpu->cooling = of_devfreq_cooling_register(gpu->pdev->dev.of_node,

• 	gpu->devfreq.devfreq);
  

• if (IS_ERR(gpu->cooling)) {

• DRM_DEV_ERROR(&gpu->pdev->dev,
  

• 		"Couldn't register GPU cooling device\n");
  

• gpu->cooling = NULL;
  

• } }

  static int enable_pwrrail(struct msm_gpu *gpu)

@@ -1056,6 +1047,4 @@ void msm_gpu_cleanup(struct msm_gpu *gpu) if (gpu->worker) { kthread_destroy_worker(gpu->worker); }

• devfreq_cooling_unregister(gpu->cooling); }

diff --git a/drivers/gpu/drm/msm/msm_gpu.h b/drivers/gpu/drm/msm/msm_gpu.h index d7cd02cd2109..93419368bac8 100644 --- a/drivers/gpu/drm/msm/msm_gpu.h +++ b/drivers/gpu/drm/msm/msm_gpu.h @@ -155,8 +155,6 @@ struct msm_gpu { struct msm_gpu_state *crashstate; /* True if the hardware supports expanded apriv (a650 and newer) */ bool hw_apriv;

• struct thermal_cooling_device *cooling; };

  static inline struct msm_gpu *dev_to_gpu(struct device *dev)

diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.c b/drivers/gpu/drm/panfrost/panfrost_devfreq.c index 56b3f5935703..2cb6300de1f1 100644 --- a/drivers/gpu/drm/panfrost/panfrost_devfreq.c +++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.c @@ -3,7 +3,6 @@

#include <linux/clk.h> #include <linux/devfreq.h> -#include <linux/devfreq_cooling.h> #include <linux/platform_device.h> #include <linux/pm_opp.h>

@@ -90,7 +89,6 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev) struct device *dev = &pfdev->pdev->dev; struct devfreq *devfreq; struct opp_table *opp_table;

• struct thermal_cooling_device *cooling; struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;

  opp_table = dev_pm_opp_set_regulators(dev, pfdev->comp->supply_names,

@@ -139,12 +137,6 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev) } pfdevfreq->devfreq = devfreq;

• cooling = devfreq_cooling_em_register(devfreq, NULL);

• if (IS_ERR(cooling))

• DRM_DEV_INFO(dev, "Failed to register cooling device\n");
  

• else

• pfdevfreq->cooling = cooling;
  

• return 0;

  err_fini:

@@ -156,11 +148,6 @@ void panfrost_devfreq_fini(struct panfrost_device *pfdev) { struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;

• if (pfdevfreq->cooling) {

• devfreq_cooling_unregister(pfdevfreq->cooling);
  

• pfdevfreq->cooling = NULL;
  

• }
• if (pfdevfreq->opp_of_table_added) { dev_pm_opp_of_remove_table(&pfdev->pdev->dev); pfdevfreq->opp_of_table_added = false;

diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h index 26ea0850be9b..690bd4affe18 100644 --- a/include/linux/devfreq.h +++ b/include/linux/devfreq.h @@ -198,6 +198,9 @@ struct devfreq {

struct srcu_notifier_head transition_notifier_list;

• /* Pointer to the cooling device if used for thermal mitigation */
• struct thermal_cooling_device *cdev;
• struct notifier_block nb_min; struct notifier_block nb_max; };