Commit Graph

5 Commits

Author SHA1 Message Date
Linus Torvalds
a35c6322e5 Merge tag 'drivers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC driver update from Kevin Hilman:
 "This contains the ARM SoC related driver updates for v3.12.  The only
  thing this cycle are core PM updates and CPUidle support for ARM's TC2
  big.LITTLE development platform"

* tag 'drivers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  cpuidle: big.LITTLE: vexpress-TC2 CPU idle driver
  ARM: vexpress: tc2: disable GIC CPU IF in tc2_pm_suspend
  drivers: irq-chip: irq-gic: introduce gic_cpu_if_down()
2013-09-09 16:08:13 -07:00
Lorenzo Pieralisi
9ee2ee0f05 ARM: vexpress: tc2: disable GIC CPU IF in tc2_pm_suspend
To prevent cores from exiting wfi when they are about to be shut down
the GIC CPU IF must be disabled so that the GIC CPU IF IRQ output line
is not asserted to the cores. wfi completion must be prevented since,
in absence of coordinating HW logic, if the power controller receives
a standbywfi signal but in the meantime the processor restarts executing
owing to a pending IRQ, the core might be reset when running in a
non-quiescent state (eg with pending load/store transactions)

Raw GIC distributor IRQ signals are routed to the power controller, that
is capable of taking core out of reset on pending IRQs even if their GIC
CPU IF is disabled, thus keeping the normal wfi behaviour.

GIC CPU IF is restored upon CPU wake-up by the respective MCPM API
consumers (ie CPU idle driver and suspend to RAM thread).

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2013-08-28 11:28:47 -07:00
Nicolas Pitre
fac2e57742 ARM: vexpress/MCPM: fix cache disable sequence when CONFIG_FRAME_POINTER=y
If CONFIG_FRAME_POINTER=y we get the following error:

arch/arm/mach-vexpress/tc2_pm.c: In function 'tc2_pm_down':
arch/arm/mach-vexpress/tc2_pm.c:200:1: error: fp cannot be used in asm here

Let's fix that by explicitly preserving r11 on the stack and removing it
from the clobber list.

Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
2013-08-14 13:05:42 -07:00
Nicolas Pitre
e607b0f985 ARM: vexpress/TC2: implement PM suspend method
Similar to power_down(), except that for a suspend, the firmware
mailbox address has to be set prior entering low power mode.

The residency argument is not used yet, so the last man always shuts
down the cluster for now.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Pawel Moll <pawel.moll@arm.com>
2013-08-07 14:55:54 +01:00
Nicolas Pitre
11b277eabe ARM: vexpress/TC2: basic PM support
This is the MCPM backend for the Virtual Express A15x2 A7x3 CoreTile
aka TC2.  This provides cluster management for SMP secondary boot and
CPU hotplug.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Pawel Moll <pawel.moll@arm.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
[PM: made it drive SCC registers directly and provide base for SPC]
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
2013-08-07 14:55:52 +01:00