If the kernel is built to support multi-ARM configuration with shmobile
support built in, then drivers/sh is not built. This contains the PM
runtime code in drivers/sh/pm_runtime.c, which implicitly enables the
module clocks for all devices, and thus is quite essential.
Without this, the state of clocks depends on implicit reset state, or on
the bootloader.
If ARCH_SHMOBILE_MULTI then build the drivers/sh directory, but ensure that
bits that may conflict (drivers/sh/clk if the common clock framework is
enabled) or are not used (drivers/sh/intc), are not built.
Also, only enable the PM runtime code when actually running on a shmobile
SoCs that needs it.
ARCH_SHMOBILE_MULTI was added a while ago by commit
efacfce5f8 ("ARM: shmobile: Introduce
ARCH_SHMOBILE_MULTI"), but drivers/sh was compiled for both
ARCH_SHMOBILE_LEGACY and ARCH_SHMOBILE_MULTI until commit
bf98c1eac1 ("ARM: Rename ARCH_SHMOBILE to
ARCH_SHMOBILE_LEGACY").
Inspired by a patch from Ben Dooks <ben.dooks@codethink.co.uk>.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
The "runtime idle" helper routine, rpm_idle(), currently ignores
return values from .runtime_idle() callbacks executed by it.
However, it turns out that many subsystems use
pm_generic_runtime_idle() which checks the return value of the
driver's callback and executes pm_runtime_suspend() for the device
unless that value is not 0. If that logic is moved to rpm_idle()
instead, pm_generic_runtime_idle() can be dropped and its users
will not need any .runtime_idle() callbacks any more.
Moreover, the PCI, SCSI, and SATA subsystems' .runtime_idle()
routines, pci_pm_runtime_idle(), scsi_runtime_idle(), and
ata_port_runtime_idle(), respectively, as well as a few drivers'
ones may be simplified if rpm_idle() calls rpm_suspend() after 0 has
been returned by the .runtime_idle() callback executed by it.
To reduce overall code bloat, make the changes described above.
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
The runtime PM platform support stub in use by ARM-based SH/R-Mobile
platforms contains nothing that's specifically ARM-related and instead of
wholly generic to anything using the clock framework.
The recent runtime PM changes interact rather badly with the lazy
disabling of clocks late in the boot process through the clock framework,
leading to situations where the runtime suspend/resume paths are entered
without a clock being actively driven due to having been lazily gated
off.
In order to correct this we can trivially tie in the aforementioned stub
as a general fallback for all SH platforms that don't presently have
their own runtime PM implementations (the corner case being SH-based
SH-Mobile platforms, which have their own stub through the hwblk API --
which in turn has bitrotted and will be subsequently adapted to use the
same stub as everyone else), regardless of whether the platforms choose
to define power domains of their own or not.
This fixes up regressions for clock framework users who also build in
runtime PM support without any specific power domains of their own, which
was previously causing the serial console to be lost when warring with
lazy clock disabling.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>