This series adds OMAP4 suspend and cpuidle support till MPU subsystem (MPUSS) off-mode. The suspend on SMP machines uses cpu-hotplug infrastructure to take down the non-boot CPUs. We put secondary CPU(CPU1 in OMAP4) to OFF state via cpu-hotplug. In cpuidle too, low power states are attempted only when the CPU1 is put to OFF state via cpu-hotplug because of hardware constraints. Timer wakeup from suspend, debug pm counters and enable_off_mode provisions are supported as well. Special thanks to Kevin Hilman <khilman@xxxxxx> for doing detail off-the list reviews. The patches are generated against mainline 2.6.38-rc5 and tested with OMAP4430 SDP and OMAP4 PANDA board. Any OMAP4 board with ES2.X silicon, below features should work with this series. On ES1.0, these PM features are not supported. 1. CPU hotplug (CPU is put into off-mode) 2. Suspend (Both CPUs put to off-mode and MPUSS to OFF/RET) 3. CPUILDE with below C-states. C1 - CPU0 ON + CPU1 ON/OFF + MPU ON + CORE ON C2 - CPU0 ON + CPU1 OFF + MPU ON + CORE ON C3 - CPU0 OFF + CPU1 OFF + MPU CSWR + CORE ON C4 - CPU0 OFF + CPU1 OFF + MPU OFF + CORE ON In OMAP4 mpuss consist of dual Cortex-A9 with per-cpu local timers GIC(Generic Interrupt Controller), SCU(Snoop Control Unit) and PL310 L2 cache controller and CPU0/CPU1 LPRM modules. CPU0, CPU1 and MPUSS have there own power domain and hence multiple low power state combinations are possible. The CPU10 and CPU1 Close switch Retention(CSWR) isn't supported by hardware. Based on various studies, measurements, hardware constraints and recommendations from hardware team, only below low power modes are supported on OMAP4. ---------------------------------------- CPU0 CPU1 MPUSS ---------------------------------------- ON ON ON OFF OFF CSWR OFF OFF OSWR OFF OFF OFF ----------------------------------------- Note: CPU0 is the master core and it is the last CPU to go down and first to wake-up when MPUSS low power states are attempted OSWR(Open Switch Retention) is not added as part of this series because it needs some power domain level support which isn't ready yet. http://www.mail-archive.com/linux-omap@xxxxxxxxxxxxxxx/msg38667.html Powerdomain INACTIVE support is also dropped because of its inconsistency between OMAP4 and OMAP3. More information on this thread - http://www.spinics.net/lists/linux-omap/msg45370.html This series has a dependency on few patches from below series which are posted earlier. - Clock domain split series [1] (Already in Paul's queue) - Few power domain patches from [2] (Already in Paul's queue) - GIC and SCU patches from [3] - Local Timer patches from [4] The cpu-hotplug and suspend works with omap2plus_defconfig. Not to damage your file system with current omap2plus_defconfig, disable ARCH_OMAP2 so that V6 and V7 support is not built together with SMP. To tryout cpuidle, CONFIG_CPU_IDLE needs to be enabled in the build. CPU-HOTPLUG commands : offline : $echo 0 > /sys/devices/system/cpu/cpu1/online online : $echo 1 > /sys/devices/system/cpu/cpu1/online Suspend :$echo mem > /sys/power/state cpuilde : To trigger cpuidle deeper C-states on OMAP4, CPU1 needs to be offlied $echo 0 > /sys/devices/system/cpu/cpu1/online To see PM debug counters, $mount -t debugfs debugfs /proc/sys/debug/ $cat /proc/sys/debug/pm_debug/count off-mode debugfs control: enable: $echo 1 > /proc/sys/debug/pm_debug/enable_off_mode disable: $echo 0 > /proc/sys/debug/pm_debug/enable_off_mode For testing, I have put together all these patches and dependencies on below git branch. git://dev.omapzoom.org/pub/scm/santosh/kernel-omap4-base.git omap4_pm_fornext Rajendra Nayak (1): omap4: cpuidle: Basic CPUidle support Santosh Shilimkar (16): omap4: pm: Add omap WakeupGen module support omap4: pm: Add SAR RAM support omap4: Export scu base address omap4: pm: Add CPUx OFF mode support omap4: pm: Initialise all the clockdomains to supported states omap4: pm: Program CPU1 to hit OFF when off-lined omap4: pm: CPU1 wakeup workaround form Low power modes omap4: pm: Add GIC save/restore support omap4: pm: Add WakeupGen save/restore support omap4: pm: Add L2 cache lowpower support omap4: suspend: Add MPUSS RET and OFF support omap4: pm-debug: Add wakeup timer and debug counters omap4: cpuidle: Add MPUSS RET OFF states omap4: cpuidle: Switch to gptimer from twd in deeper C-states. omap4: cpuidle: Allow debugfs control through enable_off_mode omap4: Remove un-used do_wfi() macro. arch/arm/mach-omap2/Makefile | 8 +- arch/arm/mach-omap2/cpuidle44xx.c | 365 +++++++++++++++++ arch/arm/mach-omap2/include/mach/omap-wakeupgen.h | 41 ++ arch/arm/mach-omap2/include/mach/omap4-common.h | 56 +++- arch/arm/mach-omap2/omap-hotplug.c | 31 ++- arch/arm/mach-omap2/omap-smp.c | 29 ++- arch/arm/mach-omap2/omap-wakeupgen.c | 287 +++++++++++++ arch/arm/mach-omap2/omap4-common.c | 28 ++- arch/arm/mach-omap2/omap4-mpuss-lowpower.c | 442 +++++++++++++++++++++ arch/arm/mach-omap2/omap4-sar-layout.h | 71 ++++ arch/arm/mach-omap2/pm-debug.c | 8 +- arch/arm/mach-omap2/pm.h | 3 + arch/arm/mach-omap2/pm44xx.c | 125 ++++++- arch/arm/mach-omap2/sleep44xx.S | 398 +++++++++++++++++++ arch/arm/plat-omap/include/plat/omap44xx.h | 1 + 15 files changed, 1870 insertions(+), 23 deletions(-) create mode 100644 arch/arm/mach-omap2/cpuidle44xx.c create mode 100644 arch/arm/mach-omap2/include/mach/omap-wakeupgen.h create mode 100644 arch/arm/mach-omap2/omap-wakeupgen.c create mode 100644 arch/arm/mach-omap2/omap4-mpuss-lowpower.c create mode 100644 arch/arm/mach-omap2/omap4-sar-layout.h create mode 100644 arch/arm/mach-omap2/sleep44xx.S Regrads, Santosh [1] http://www.spinics.net/lists/linux-omap/msg44153.html [2] http://www.mail-archive.com/linux-omap@xxxxxxxxxxxxxxx/msg43257.html [3] http://www.mail-archive.com/linux-omap@xxxxxxxxxxxxxxx/msg42939.html [4] http://www.spinics.net/lists/linux-omap/msg45710.html -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
