This patch is V3 of the SuperH Mobile Runtime PM platform bus
implentation matching Rafael's Runtime PM v16.
The code gets invoked from the SuperH specific Runtime PM
platform bus functions that override the weak symbols for:
- platform_pm_runtime_suspend()
- platform_pm_runtime_resume()
- platform_pm_runtime_idle()
This Runtime PM implementation performs two levels of power
management. At the time of platform bus runtime suspend the
clock to the device is stopped instantly. Later on if all
devices within the power domain has their clocks stopped
then the device driver ->runtime_suspend() callbacks are
used to save hardware register state for each device.
Device driver ->runtime_suspend() calls are scheduled from
cpuidle context using platform_pm_runtime_suspend_idle().
When all devices have been fully suspended the processor
is allowed to enter deep sleep from cpuidle.
The runtime resume operation turns on clocks and also
restores registers if needed. It is worth noting that the
devices start in a suspended state and the device driver
is responsible for calling runtime resume before accessing
the actual hardware.
In this particular platform bus implementation runtime
resume is not allowed from interrupt context. Runtime
suspend is however allowed from interrupt context as
long as the synchronous functions are avoided.
[ updated for v17 -- PFM. ]
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch adds cpuidle support for SuperH Mobile.
The sleep mode selected by cpuidle is compared with
the mode selected by the hwblk sleep code and the
best allowed mode is entered.
At this point "Sleep mode" and "Sleep mode + SF" are
supported. This code can easily be extended to support
"Software suspend mode", but the assembly code must
first be updated to avoid loosing interrupts.
Also, update the code to only copy the assembly snippet
into internal memory once at bootup.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Magnus Damm