[PATCH V3 14/19] Documentation: DT: bindings: Add power domain info for NVIDIA PMC
From: Thierry Reding <hidden>
Date: 2015-07-17 09:38:42
Also in:
linux-devicetree, linux-pm, linux-tegra
On Mon, Jul 13, 2015 at 01:39:52PM +0100, Jon Hunter wrote:
quoted hunk
Add power-domain binding documentation for the NVIDIA PMC driver in order to support generic power-domains. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> --- .../bindings/arm/tegra/nvidia,tegra20-pmc.txt | 99 ++++++++++++++++++++++ 1 file changed, 99 insertions(+)diff --git a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt index 02c27004d4a8..93357a450576 100644 --- a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt +++ b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt@@ -1,5 +1,7 @@ NVIDIA Tegra Power Management Controller (PMC) +== Power Management Controller Node == + The PMC block interacts with an external Power Management Unit. The PMC mostly controls the entry and exit of the system from different sleep modes. It provides power-gating controllers for SoC and CPU power-islands.@@ -68,6 +70,10 @@ Optional properties for hardware-triggered thermal reset (inside 'i2c-thermtrip' Defaults to 0. Valid values are described in section 12.5.2 "Pinmux Support" of the Tegra4 Technical Reference Manual. +Optional nodes: +- pm-domains : This node contains a hierarchy of PM domain nodes, which should + match the power-domains on the Tegra SoC.
Perhaps call this simply power-domains to match the property name in consumer nodes?
quoted hunk
+ Example: / SoC dts including file@@ -113,3 +119,96 @@ pmc at 7000f400 { }; ... }; + + +== PM Domain Nodes == + +Each of the PM domain nodes represents a power-domain on the Tegra SoC +that can be power-gated by the PMC and should be named appropriately. + +Required properties: + - clocks: Must contain an entry for each clock required by + the PMC for controlling a power-gate. See + ../clocks/clock-bindings.txt for details. + - resets: Must contain an entry for each reset required by + the PMC for controlling a power-gate. See + ../reset/reset.txt for details. + - nvidia,powergate: Integer cell that contains an identifier for the + PMC power-gate that is associated with the + power-domain. Please refer to the Tegra TRM for + more details.
I find this really difficult to read. Can we use a more conventional format such as: - clocks: Must contain... ... for details. ?
+ - #power-domain-cells: Must be 0. + +Optional properties: + - nvidia,swgroups: Provides details of the software groups that are + associated with a specific power-domain. The + software group specifier consists of a phandle + pointing to the memory controller and a list of + one or more integer cells for each software group + associated with the power domain. The length of + the list of integer cells is specified by + #nvidia,swgroup-cells. + - #nvidia,swgroup-cells: Must be 1 or more. See nvidia,swgroups for + more details.
That's not how this usually works. #*-cells properties determine the
number of cells required per <phandle spec> pair. So I think this should
be more along the lines of:
- #nvidia,swgroups: A list of software groups associated with a
specific power domain. This consists of a list of phandle and
SWGROUP ID pairs, where the phandle points to the memory
controller node.
- #nvidia,swgroup-cells: Must be 1. The single cell in the specifier
denotes the ID of the software group.
+
+Example:
+
+ pmc at 0,7000e400 {
+ compatible = "nvidia,tegra124-pmc";
+ reg = <0x0 0x7000e400 0x0 0x400>;
+ clocks = <&tegra_car TEGRA124_CLK_PCLK>, <&clk32k_in>;
+ clock-names = "pclk", "clk32k_in";
+
+ pm-domains {power-domains would convey more clearly what this is about.
+ ...
+
+ pd_sor: sor-power-domain {I don't think it's useful to repeat the -power-domain suffix for all these nodes. Thierry -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: not available URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20150717/9a76a930/attachment.sig>