Add DT binding documentation for Sierra PHY. The PHY supports
a number of different protocols, including PCIe and USB.
The PHY lanes may be configured as single or multi-lane links.
Each link is treated as a separate subnode. For example, if
there are 4 lanes in total the first 2 may be configured as
a multi-lane PCIe link while the other two are single lane
USB links, and in this case there would be 3 subnodes.
There are two resets for the PHY block, and additional resets,
one for each lane. For multi-lane links, only the reset for
the master lane is required, the resets on other lanes have no
effect.
Signed-off-by: Alan Douglas <adouglas@xxxxxxxxxxx>
---
.../devicetree/bindings/phy/cdns-sierra-phy.txt | 65 ++++++++++++++++++++++
1 file changed, 65 insertions(+)
create mode 100644 Documentation/devicetree/bindings/phy/cdns-sierra-phy.txt
diff --git a/Documentation/devicetree/bindings/phy/cdns-sierra-phy.txt b/Documentation/devicetree/bindings/phy/cdns-sierra-phy.txt
new file mode 100644
index 0000000..94a8a7f
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/cdns-sierra-phy.txt
@@ -0,0 +1,65 @@
+Cadence Sierra PHY
+-----------------------
+
+Required properties:
+- compatible: cdns,sierra-phy-t0
+- clocks: Must contain an entry in clock-names.
+ See ../clocks/clock-bindings.txt for details.
+- clock-names: Must be "phy_clk"
+- resets: Must contain an entry for each in reset-names.
+ See ../reset/reset.txt for details.
+- reset-names: Must include "sierra_reset" and "sierra_apb" and one for each
+ sub-node.
+ "sierra_reset" must control the reset line to the PHY.
+ "sierra_apb" must control the reset line to the APB PHY
+ interface.
+ Resets for each subnode must control the master lane for the
+ subnode lane group.
+- reg: register range for the PHY.
+- reg-names: Must be "reg".
+- #address-cells: Should be 1
+- #size-cells: Should be 0
+
+Optional properties:
+- cdns,autoconf: If present, indicates that the PHY registers will
+ be configured by hardware. If not present, all
+ sub-node optional properties must be provided.
+
+Sub-nodes:
+ Each group of PHY lanes with a single master lane should be represented as
+ a sub-node. Note that the actual configuration of each lane is determined by
+ hardware strapping, and must match the configuration specified here.
+
+Sub-node required properties:
+- #phy-cells: Generic PHY binding; must be 0.
+
+Sub-node optional properties:
+- reg: The master lane number.
+- cdns,num-lanes: Number of lanes in this group. From 1 to 4.
+- cdns,phy-type: Can be PHY_TYPE_PCIE or PHY_TYPE_USB3, depending on
+ configuration of lanes.
+
+Example:
+ pcie_phy4: pcie-phy4@fd240000 {
+ compatible = "cdns,sierra-phy-t0";
+ reg = <0x0 0xfd240000 0x0 0x40000>;
+ reg-names = "reg";
+ resets = <&phyrst 0>, <&phyrst 1>,<&phyrst 2>,<&phyrst 4>;
+ reset-names = "sierra_reset","sierra_apb","pcie_phy0",pcie_phy1;
+ clocks = <&phyclock>;
+ clock-names = "phy_clk";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ pcie0_phy0: pcie-phy0@0 {
+ reg = <0>;
+ cdns,num-lanes = <2>;
+ #phy-cells = <0>;
+ cdns,phy-type = <PHY_TYPE_PCIE>;
+ };
+ pcie0_phy1: pcie-phy1@0 {
+ reg = <2>;
+ cdns,num-lanes = <1>;
+ #phy-cells = <0>;
+ cdns,phy-type = <PHY_TYPE_PCIE>;
+ };
+
--
1.9.0
