We have various bootloaders for Exynos4210 machines. Some of they
set the ARM core frequency at boot time even when the boot is a resume
from suspend-to-RAM. Such changes may create inconsistency in the
data of CPUFREQ driver and have incurred hang issues with suspend-to-RAM.
This patch enables to save and restore CPU frequencies with pm-notifier and
sets the frequency at the initial (boot-time) value so that there wouldn't
be any inconsistency between bootloader and kernel. This patch does not
use CPUFREQ's suspend/resume callbacks because they are syscore-ops, which
do not allow to use mutex that is being used by regulators that are used by
the target function.
This also prevents any CPUFREQ transitions during suspend-resume context,
which could be dangerous at noirq-context along with regulator framework.
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Dave Jones <davej@redhat.com>
This patch enables 'scaling_available_frequencies' attribute
showing list of available frequencies.
Signed-off-by: Donggeun Kim <dg77.kim@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: KyungMin Park <kyungmin.park@samsung.com>
Signed-off-by: Dave Jones <davej@redhat.com>
The following symbols are needlessly defined global:
exynos4_verify_speed
exynos4_getspeed
exynos4_set_clkdiv
Make them static.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Dave Jones <davej@redhat.com>
According to discussion of the ARM arch subsystem migration,
ARM cpufreq drivers move to drivers/cpufreq. So this patch
adds Kconfig.arm for ARM like x86 and adds Samsung S5PV210
and EXYNOS4210 cpufreq driver compile in there.
As a note, otherw will be moved.
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Dave Jones <davej@redhat.com>