From: Chanwoo Choi cw00.choi@samsung.com
[ Upstream commit 490a421bc575d1bf391a6ad5b582dcfbd0037724 ]
Add debugfs interface to provide debugging information of devfreq device. It contains 'devfreq_summary' entry to show the summary of registered devfreq devices as following and the additional debugfs file will be added. - /sys/kernel/debug/devfreq/devfreq_summary
[Detailed description of each field of 'devfreq_summary' debugfs file] - dev_name : Device name of h/w - dev : Device name made by devfreq core - parent_dev : If devfreq device uses the passive governor, show parent devfreq device name. Otherwise, show 'null'. - governor : Devfreq governor name - polling_ms : If devfreq device uses the simple_ondemand governor, polling_ms is necessary for the period. (unit: millisecond) - cur_freq_Hz : Current frequency (unit: Hz) - min_freq_Hz : Minimum frequency (unit: Hz) - max_freq_Hz : Maximum frequency (unit: Hz)
[For example on Exynos5422-based Odroid-XU3 board] $ cat /sys/kernel/debug/devfreq/devfreq_summary dev_name dev parent_dev governor polling_ms cur_freq_Hz min_freq_Hz max_freq_Hz ------------------------------ ---------- ---------- --------------- ---------- ------------ ------------ ------------ 10c20000.memory-controller devfreq0 null simple_ondemand 0 165000000 165000000 825000000 soc:bus_wcore devfreq1 null simple_ondemand 50 532000000 88700000 532000000 soc:bus_noc devfreq2 devfreq1 passive 0 111000000 66600000 111000000 soc:bus_fsys_apb devfreq3 devfreq1 passive 0 222000000 111000000 222000000 soc:bus_fsys devfreq4 devfreq1 passive 0 200000000 75000000 200000000 soc:bus_fsys2 devfreq5 devfreq1 passive 0 200000000 75000000 200000000 soc:bus_mfc devfreq6 devfreq1 passive 0 333000000 83250000 333000000 soc:bus_gen devfreq7 devfreq1 passive 0 266000000 88700000 266000000 soc:bus_peri devfreq8 devfreq1 passive 0 66600000 66600000 66600000 soc:bus_g2d devfreq9 devfreq1 passive 0 333000000 83250000 333000000 soc:bus_g2d_acp devfreq10 devfreq1 passive 0 266000000 66500000 266000000 soc:bus_jpeg devfreq11 devfreq1 passive 0 300000000 75000000 300000000 soc:bus_jpeg_apb devfreq12 devfreq1 passive 0 166500000 83250000 166500000 soc:bus_disp1_fimd devfreq13 devfreq1 passive 0 200000000 120000000 200000000 soc:bus_disp1 devfreq14 devfreq1 passive 0 300000000 120000000 300000000 soc:bus_gscl_scaler devfreq15 devfreq1 passive 0 300000000 150000000 300000000 soc:bus_mscl devfreq16 devfreq1 passive 0 666000000 84000000 666000000
[lkp: Reported the build error] Reported-by: kbuild test robot lkp@intel.com Signed-off-by: Chanwoo Choi cw00.choi@samsung.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/devfreq/devfreq.c | 82 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+)
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 554d155106a5f..e99f082d15df5 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -10,6 +10,7 @@ #include <linux/kernel.h> #include <linux/kmod.h> #include <linux/sched.h> +#include <linux/debugfs.h> #include <linux/errno.h> #include <linux/err.h> #include <linux/init.h> @@ -33,6 +34,7 @@ #define HZ_PER_KHZ 1000
static struct class *devfreq_class; +static struct dentry *devfreq_debugfs;
/* * devfreq core provides delayed work based load monitoring helper @@ -1614,6 +1616,81 @@ static struct attribute *devfreq_attrs[] = { }; ATTRIBUTE_GROUPS(devfreq);
+/** + * devfreq_summary_show() - Show the summary of the devfreq devices + * @s: seq_file instance to show the summary of devfreq devices + * @data: not used + * + * Show the summary of the devfreq devices via 'devfreq_summary' debugfs file. + * It helps that user can know the detailed information of the devfreq devices. + * + * Return 0 always because it shows the information without any data change. + */ +static int devfreq_summary_show(struct seq_file *s, void *data) +{ + struct devfreq *devfreq; + struct devfreq *p_devfreq = NULL; + unsigned long cur_freq, min_freq, max_freq; + unsigned int polling_ms; + + seq_printf(s, "%-30s %-10s %-10s %-15s %10s %12s %12s %12s\n", + "dev_name", + "dev", + "parent_dev", + "governor", + "polling_ms", + "cur_freq_Hz", + "min_freq_Hz", + "max_freq_Hz"); + seq_printf(s, "%30s %10s %10s %15s %10s %12s %12s %12s\n", + "------------------------------", + "----------", + "----------", + "---------------", + "----------", + "------------", + "------------", + "------------"); + + mutex_lock(&devfreq_list_lock); + + list_for_each_entry_reverse(devfreq, &devfreq_list, node) { +#if IS_ENABLED(CONFIG_DEVFREQ_GOV_PASSIVE) + if (!strncmp(devfreq->governor_name, DEVFREQ_GOV_PASSIVE, + DEVFREQ_NAME_LEN)) { + struct devfreq_passive_data *data = devfreq->data; + + if (data) + p_devfreq = data->parent; + } else { + p_devfreq = NULL; + } +#endif + + mutex_lock(&devfreq->lock); + cur_freq = devfreq->previous_freq, + get_freq_range(devfreq, &min_freq, &max_freq); + polling_ms = devfreq->profile->polling_ms, + mutex_unlock(&devfreq->lock); + + seq_printf(s, + "%-30s %-10s %-10s %-15s %10d %12ld %12ld %12ld\n", + dev_name(devfreq->dev.parent), + dev_name(&devfreq->dev), + p_devfreq ? dev_name(&p_devfreq->dev) : "null", + devfreq->governor_name, + polling_ms, + cur_freq, + min_freq, + max_freq); + } + + mutex_unlock(&devfreq_list_lock); + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(devfreq_summary); + static int __init devfreq_init(void) { devfreq_class = class_create(THIS_MODULE, "devfreq"); @@ -1630,6 +1707,11 @@ static int __init devfreq_init(void) } devfreq_class->dev_groups = devfreq_groups;
+ devfreq_debugfs = debugfs_create_dir("devfreq", NULL); + debugfs_create_file("devfreq_summary", 0444, + devfreq_debugfs, NULL, + &devfreq_summary_fops); + return 0; } subsys_initcall(devfreq_init);