Commit Graph

6 Commits

Author SHA1 Message Date
Martin Blumenstingl
3f5b995904 thermal: devfreq_cooling: inline all stubs for CONFIG_DEVFREQ_THERMAL=n
When CONFIG_DEVFREQ_THERMAL is disabled all functions except
of_devfreq_cooling_register_power() were already inlined. Also inline
the last function to avoid compile errors when multiple drivers call
of_devfreq_cooling_register_power() when CONFIG_DEVFREQ_THERMAL is not
set. Compilation failed with the following message:
  multiple definition of `of_devfreq_cooling_register_power'
(which then lists all usages of of_devfreq_cooling_register_power())

Thomas Zimmermann reported this problem [0] on a kernel config with
CONFIG_DRM_LIMA={m,y}, CONFIG_DRM_PANFROST={m,y} and
CONFIG_DEVFREQ_THERMAL=n after both, the lima and panfrost drivers
gained devfreq cooling support.

[0] https://www.spinics.net/lists/dri-devel/msg252825.html

Fixes: a76caf55e5 ("thermal: Add devfreq cooling")
Cc: stable@vger.kernel.org
Reported-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Tested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200403205133.1101808-1-martin.blumenstingl@googlemail.com
2020-04-07 10:45:15 +02:00
Lukasz Luba
2be83da85a thermal: devfreq_cooling: add new interface for direct power read
This patch introduces a new interface for device drivers connected to
devfreq_cooling in the thermal framework: get_real_power().

Some devices have more sophisticated methods (like power counters)
to approximate the actual power that they use.
In the previous implementation we had a pre-calculated power
table which was then scaled by 'utilization'
('busy_time' and 'total_time' taken from devfreq 'last_status').

With this new interface the driver can provide more precise data
regarding actual power to the thermal governor every time the power
budget is calculated. We then use this value and calculate the real
resource utilization scaling factor.

Reviewed-by: Chris Diamand <chris.diamand@arm.com>
Acked-by: Javi Merino <javi.merino@kernel.org>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
2017-05-05 15:54:45 +08:00
Javi Merino
3aa5374376 devfreq_cooling: pass a pointer to devfreq in the power model callbacks
When the devfreq cooling device was designed, it was an oversight not to
pass a pointer to the struct devfreq as the first parameters of the
callbacks.  The design patterns of the kernel suggest it for a good
reason.

By passing a pointer to struct devfreq, the driver can register one
function that works with multiple devices.  With the current
implementation, a driver that can work with multiple devices has to
create multiple copies of the same function with different parameters so
that each devfreq_cooling_device can use the appropriate one.  By
passing a pointer to struct devfreq, the driver can identify which
device it's referring to.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Reviewed-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Ørjan Eide <orjan.eide@arm.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2016-11-23 10:07:35 +08:00
Lukasz Luba
1cea4e7776 devfreq_cooling: make the structs devfreq_cooling_xxx visible for all
Currently the protection #ifdef CONFIG_DEVFREQ_THERMAL cuts the needed
structures devfreq_cooling_ops and devfreq_cooling_device.
The functions which are supposed to provide the empty implementation complain
about unknown structures.
Similar solution is present in include/linux/devfreq.h.

Reviewed-by: Ørjan Eide <orjan.eide@arm.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2016-11-23 10:07:35 +08:00
Javi Merino
3c99c2cef7 thermal: devfreq_cooling: use a thermal_cooling_device for register and unregister
Be consistent with what other cooling devices do and return a struct
thermal_cooling_device * on register.  Also, for the unregister, accept
a struct thermal_cooling_device * as parameter.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2015-11-02 13:14:44 -08:00
Ørjan Eide
a76caf55e5 thermal: Add devfreq cooling
Add a generic thermal cooling device for devfreq, that is similar to
cpu_cooling.

The device must use devfreq.  In order to use the power extension of the
cooling device, it must have registered its OPPs using the OPP library.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Ørjan Eide <orjan.eide@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2015-10-30 10:21:01 -07:00