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author | Grant Likely <grant.likely@secretlab.ca> | 2011-01-26 10:10:40 -0700 |
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committer | Grant Likely <grant.likely@secretlab.ca> | 2011-01-31 00:09:01 -0700 |
commit | d524dac9279b6a41ffdf7ff7958c577f2e387db6 (patch) | |
tree | 294166d18a1c89c4cebb2571ea7b124876fb01ef /Documentation/devicetree/bindings/powerpc/4xx/cpm.txt | |
parent | 1bae4ce27c9c90344f23c65ea6966c50ffeae2f5 (diff) | |
download | op-kernel-dev-d524dac9279b6a41ffdf7ff7958c577f2e387db6.zip op-kernel-dev-d524dac9279b6a41ffdf7ff7958c577f2e387db6.tar.gz |
dt: Move device tree documentation out of powerpc directory
The device tree is used by more than just PowerPC. Make the documentation
directory available to all.
v2: reorganized files while moving to create arch and driver specific
directories.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Diffstat (limited to 'Documentation/devicetree/bindings/powerpc/4xx/cpm.txt')
-rw-r--r-- | Documentation/devicetree/bindings/powerpc/4xx/cpm.txt | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/powerpc/4xx/cpm.txt b/Documentation/devicetree/bindings/powerpc/4xx/cpm.txt new file mode 100644 index 0000000..ee45980 --- /dev/null +++ b/Documentation/devicetree/bindings/powerpc/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>; +}; |