From d164f6d4f9108126f69ba2963cf6fb7ef4ba9232 Mon Sep 17 00:00:00 2001 From: Victor Gallardo Date: Fri, 8 Oct 2010 10:25:27 +0000 Subject: powerpc/4xx: Add suspend and idle support Add suspend/resume support for 4xx compatible CPUs. See /sys/power/state for available power states configured in. Add two different idle states (idle-wait and idle-doze) controlled via sysfs. Default is idle-wait. cat /sys/devices/system/cpu/cpu0/idle [wait] doze To save additional power, use idle-doze. echo doze > /sys/devices/system/cpu/cpu0/idle cat /sys/devices/system/cpu/cpu0/idle wait [doze] Signed-off-by: Victor Gallardo Signed-off-by: Josh Boyer --- Documentation/powerpc/dts-bindings/4xx/cpm.txt | 52 ++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 Documentation/powerpc/dts-bindings/4xx/cpm.txt (limited to 'Documentation/powerpc') diff --git a/Documentation/powerpc/dts-bindings/4xx/cpm.txt b/Documentation/powerpc/dts-bindings/4xx/cpm.txt new file mode 100644 index 000000000000..ee459806d35e --- /dev/null +++ b/Documentation/powerpc/dts-bindings/4xx/cpm.txt @@ -0,0 +1,52 @@ +PPC4xx Clock Power Management (CPM) node + +Required properties: + - compatible : compatible list, currently only "ibm,cpm" + - dcr-access-method : "native" + - dcr-reg : < DCR register range > + +Optional properties: + - er-offset : All 4xx SoCs with a CPM controller have + one of two different order for the CPM + registers. Some have the CPM registers + in the following order (ER,FR,SR). The + others have them in the following order + (SR,ER,FR). For the second case set + er-offset = <1>. + - unused-units : specifier consist of one cell. For each + bit in the cell, the corresponding bit + in CPM will be set to turn off unused + devices. + - idle-doze : specifier consist of one cell. For each + bit in the cell, the corresponding bit + in CPM will be set to turn off unused + devices. This is usually just CPM[CPU]. + - standby : specifier consist of one cell. For each + bit in the cell, the corresponding bit + in CPM will be set on standby and + restored on resume. + - suspend : specifier consist of one cell. For each + bit in the cell, the corresponding bit + in CPM will be set on suspend (mem) and + restored on resume. Note, for standby + and suspend the corresponding bits can + be different or the same. Usually for + standby only class 2 and 3 units are set. + However, the interface does not care. + If they are the same, the additional + power saving will be seeing if support + is available to put the DDR in self + refresh mode and any additional power + saving techniques for the specific SoC. + +Example: + CPM0: cpm { + compatible = "ibm,cpm"; + dcr-access-method = "native"; + dcr-reg = <0x160 0x003>; + er-offset = <0>; + unused-units = <0x00000100>; + idle-doze = <0x02000000>; + standby = <0xfeff0000>; + suspend = <0xfeff791d>; +}; -- cgit v1.2.3