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+* Clock Block on Freescale QorIQ Platforms
+
+Freescale QorIQ chips take primary clocking input from the external
+SYSCLK signal. The SYSCLK input (frequency) is multiplied using
+multiple phase locked loops (PLL) to create a variety of frequencies
+which can then be passed to a variety of internal logic, including
+cores and peripheral IP blocks.
+Please refer to the Reference Manual for details.
+
+All references to "1.0" and "2.0" refer to the QorIQ chassis version to
+which the chip complies.
+
+Chassis Version Example Chips
+--------------- -------------
+1.0 p4080, p5020, p5040
+2.0 t4240, b4860
+
+1. Clock Block Binding
+
+Required properties:
+- compatible: Should contain a chip-specific clock block compatible
+ string and (if applicable) may contain a chassis-version clock
+ compatible string.
+
+ Chip-specific strings are of the form "fsl,<chip>-clockgen", such as:
+ * "fsl,p2041-clockgen"
+ * "fsl,p3041-clockgen"
+ * "fsl,p4080-clockgen"
+ * "fsl,p5020-clockgen"
+ * "fsl,p5040-clockgen"
+ * "fsl,t1023-clockgen"
+ * "fsl,t1024-clockgen"
+ * "fsl,t1040-clockgen"
+ * "fsl,t1042-clockgen"
+ * "fsl,t2080-clockgen"
+ * "fsl,t2081-clockgen"
+ * "fsl,t4240-clockgen"
+ * "fsl,b4420-clockgen"
+ * "fsl,b4860-clockgen"
+ * "fsl,ls1012a-clockgen"
+ * "fsl,ls1021a-clockgen"
+ * "fsl,ls1028a-clockgen"
+ * "fsl,ls1043a-clockgen"
+ * "fsl,ls1046a-clockgen"
+ * "fsl,ls1088a-clockgen"
+ * "fsl,ls2080a-clockgen"
+ Chassis-version clock strings include:
+ * "fsl,qoriq-clockgen-1.0": for chassis 1.0 clocks
+ * "fsl,qoriq-clockgen-2.0": for chassis 2.0 clocks
+- reg: Describes the address of the device's resources within the
+ address space defined by its parent bus, and resource zero
+ represents the clock register set
+
+Optional properties:
+- ranges: Allows valid translation between child's address space and
+ parent's. Must be present if the device has sub-nodes.
+- #address-cells: Specifies the number of cells used to represent
+ physical base addresses. Must be present if the device has
+ sub-nodes and set to 1 if present
+- #size-cells: Specifies the number of cells used to represent
+ the size of an address. Must be present if the device has
+ sub-nodes and set to 1 if present
+- clock-frequency: Input system clock frequency (SYSCLK)
+- clocks: If clock-frequency is not specified, sysclk may be provided
+ as an input clock. Either clock-frequency or clocks must be
+ provided.
+ A second input clock, called "coreclk", may be provided if
+ core PLLs are based on a different input clock from the
+ platform PLL.
+- clock-names: Required if a coreclk is present. Valid names are
+ "sysclk" and "coreclk".
+
+2. Clock Provider
+
+The clockgen node should act as a clock provider, though in older device
+trees the children of the clockgen node are the clock providers.
+
+When the clockgen node is a clock provider, #clock-cells = <2>.
+The first cell of the clock specifier is the clock type, and the
+second cell is the clock index for the specified type.
+
+ Type# Name Index Cell
+ 0 sysclk must be 0
+ 1 cmux index (n in CLKCnCSR)
+ 2 hwaccel index (n in CLKCGnHWACSR)
+ 3 fman 0 for fm1, 1 for fm2
+ 4 platform pll n=pll/(n+1). For example, when n=1,
+ that means output_freq=PLL_freq/2.
+ 5 coreclk must be 0
+
+3. Example
+
+ clockgen: global-utilities@e1000 {
+ compatible = "fsl,p5020-clockgen", "fsl,qoriq-clockgen-1.0";
+ clock-frequency = <133333333>;
+ reg = <0xe1000 0x1000>;
+ #clock-cells = <2>;
+ };
+
+ fman@400000 {
+ ...
+ clocks = <&clockgen 3 0>;
+ ...
+ };
+}
+4. Legacy Child Nodes
+
+NOTE: These nodes are deprecated. Kernels should continue to support
+device trees with these nodes, but new device trees should not use them.
+
+Most of the bindings are from the common clock binding[1].
+ [1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+
+Required properties:
+- compatible : Should include one of the following:
+ * "fsl,qoriq-core-pll-1.0" for core PLL clocks (v1.0)
+ * "fsl,qoriq-core-pll-2.0" for core PLL clocks (v2.0)
+ * "fsl,qoriq-core-mux-1.0" for core mux clocks (v1.0)
+ * "fsl,qoriq-core-mux-2.0" for core mux clocks (v2.0)
+ * "fsl,qoriq-sysclk-1.0": for input system clock (v1.0).
+ It takes parent's clock-frequency as its clock.
+ * "fsl,qoriq-sysclk-2.0": for input system clock (v2.0).
+ It takes parent's clock-frequency as its clock.
+ * "fsl,qoriq-platform-pll-1.0" for the platform PLL clock (v1.0)
+ * "fsl,qoriq-platform-pll-2.0" for the platform PLL clock (v2.0)
+- #clock-cells: From common clock binding. The number of cells in a
+ clock-specifier. Should be <0> for "fsl,qoriq-sysclk-[1,2].0"
+ clocks, or <1> for "fsl,qoriq-core-pll-[1,2].0" clocks.
+ For "fsl,qoriq-core-pll-[1,2].0" clocks, the single
+ clock-specifier cell may take the following values:
+ * 0 - equal to the PLL frequency
+ * 1 - equal to the PLL frequency divided by 2
+ * 2 - equal to the PLL frequency divided by 4
+
+Recommended properties:
+- clocks: Should be the phandle of input parent clock
+- clock-names: From common clock binding, indicates the clock name
+- clock-output-names: From common clock binding, indicates the names of
+ output clocks
+- reg: Should be the offset and length of clock block base address.
+ The length should be 4.
+
+Legacy Example:
+/ {
+ clockgen: global-utilities@e1000 {
+ compatible = "fsl,p5020-clockgen", "fsl,qoriq-clockgen-1.0";
+ ranges = <0x0 0xe1000 0x1000>;
+ clock-frequency = <133333333>;
+ reg = <0xe1000 0x1000>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ sysclk: sysclk {
+ #clock-cells = <0>;
+ compatible = "fsl,qoriq-sysclk-1.0";
+ clock-output-names = "sysclk";
+ };
+
+ pll0: pll0@800 {
+ #clock-cells = <1>;
+ reg = <0x800 0x4>;
+ compatible = "fsl,qoriq-core-pll-1.0";
+ clocks = <&sysclk>;
+ clock-output-names = "pll0", "pll0-div2";
+ };
+
+ pll1: pll1@820 {
+ #clock-cells = <1>;
+ reg = <0x820 0x4>;
+ compatible = "fsl,qoriq-core-pll-1.0";
+ clocks = <&sysclk>;
+ clock-output-names = "pll1", "pll1-div2";
+ };
+
+ mux0: mux0@0 {
+ #clock-cells = <0>;
+ reg = <0x0 0x4>;
+ compatible = "fsl,qoriq-core-mux-1.0";
+ clocks = <&pll0 0>, <&pll0 1>, <&pll1 0>, <&pll1 1>;
+ clock-names = "pll0", "pll0-div2", "pll1", "pll1-div2";
+ clock-output-names = "cmux0";
+ };
+
+ mux1: mux1@20 {
+ #clock-cells = <0>;
+ reg = <0x20 0x4>;
+ compatible = "fsl,qoriq-core-mux-1.0";
+ clocks = <&pll0 0>, <&pll0 1>, <&pll1 0>, <&pll1 1>;
+ clock-names = "pll0", "pll0-div2", "pll1", "pll1-div2";
+ clock-output-names = "cmux1";
+ };
+
+ platform-pll: platform-pll@c00 {
+ #clock-cells = <1>;
+ reg = <0xc00 0x4>;
+ compatible = "fsl,qoriq-platform-pll-1.0";
+ clocks = <&sysclk>;
+ clock-output-names = "platform-pll", "platform-pll-div2";
+ };
+ };
+};
+
+Example for legacy clock consumer:
+
+/ {
+ cpu0: PowerPC,e5500@0 {
+ ...
+ clocks = <&mux0>;
+ ...
+ };
+};