Chanwoo Choi
490a421bc5
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>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.