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-rw-r--r--doc/device-tree-bindings/bus/simple-pm-bus.txt44
-rw-r--r--doc/device-tree-bindings/mfd/kendryte,k210-sysctl.txt33
-rw-r--r--doc/device-tree-bindings/reset/syscon-reset.txt36
3 files changed, 113 insertions, 0 deletions
diff --git a/doc/device-tree-bindings/bus/simple-pm-bus.txt b/doc/device-tree-bindings/bus/simple-pm-bus.txt
new file mode 100644
index 0000000000..6f15037131
--- /dev/null
+++ b/doc/device-tree-bindings/bus/simple-pm-bus.txt
@@ -0,0 +1,44 @@
+Simple Power-Managed Bus
+========================
+
+A Simple Power-Managed Bus is a transparent bus that doesn't need a real
+driver, as it's typically initialized by the boot loader.
+
+However, its bus controller is part of a PM domain, or under the control of a
+functional clock. Hence, the bus controller's PM domain and/or clock must be
+enabled for child devices connected to the bus (either on-SoC or externally)
+to function.
+
+While "simple-pm-bus" follows the "simple-bus" set of properties, as specified
+in the Devicetree Specification, it is not an extension of "simple-bus".
+
+
+Required properties:
+ - compatible: Must contain at least "simple-pm-bus".
+ Must not contain "simple-bus".
+ It's recommended to let this be preceded by one or more
+ vendor-specific compatible values.
+ - #address-cells, #size-cells, ranges: Must describe the mapping between
+ parent address and child address spaces.
+
+Optional platform-specific properties for clock or PM domain control (at least
+one of them is required):
+ - clocks: Must contain a reference to the functional clock(s),
+ - power-domains: Must contain a reference to the PM domain.
+Please refer to the binding documentation for the clock and/or PM domain
+providers for more details.
+
+
+Example:
+
+ bsc: bus@fec10000 {
+ compatible = "renesas,bsc-sh73a0", "renesas,bsc",
+ "simple-pm-bus";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges = <0 0 0x20000000>;
+ reg = <0xfec10000 0x400>;
+ interrupts = <0 39 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&zb_clk>;
+ power-domains = <&pd_a4s>;
+ };
diff --git a/doc/device-tree-bindings/mfd/kendryte,k210-sysctl.txt b/doc/device-tree-bindings/mfd/kendryte,k210-sysctl.txt
new file mode 100644
index 0000000000..5b24abcb62
--- /dev/null
+++ b/doc/device-tree-bindings/mfd/kendryte,k210-sysctl.txt
@@ -0,0 +1,33 @@
+Kendryte K210 Sysctl
+
+This binding describes the K210 sysctl device, which contains many miscellaneous
+registers controlling system functionality. This node is a register map and can
+be reference by other bindings which need a phandle to the K210 sysctl regmap.
+
+Required properties:
+- compatible: should be
+ "kendryte,k210-sysctl", "syscon", "simple-mfd"
+- reg: address and length of the sysctl registers
+- reg-io-width: must be <4>
+
+Clock sub-node
+
+This node is a binding for the clock tree driver
+
+Required properties:
+- compatible: should be "kendryte,k210-clk"
+- clocks: phandle to the "in0" external oscillator
+- #clock-cells: must be <1>
+
+Example:
+sysctl: syscon@50440000 {
+ compatible = "kendryte,k210-sysctl", "syscon", "simple-mfd";
+ reg = <0x50440000 0x100>;
+ reg-io-width = <4>;
+
+ sysclk: clock-controller {
+ compatible = "kendryte,k210-clk";
+ clocks = <&in0>;
+ #clock-cells = <1>;
+ };
+};
diff --git a/doc/device-tree-bindings/reset/syscon-reset.txt b/doc/device-tree-bindings/reset/syscon-reset.txt
new file mode 100644
index 0000000000..f136b3d225
--- /dev/null
+++ b/doc/device-tree-bindings/reset/syscon-reset.txt
@@ -0,0 +1,36 @@
+Generic SYSCON mapped register reset driver
+
+This is a generic reset driver using syscon to map the reset register.
+The reset is generally performed with a write to the reset register
+defined by the register map pointed by syscon reference plus the offset and
+shifted by the reset specifier/
+
+To assert a reset on some device, the equivalent of the following operation is
+performed, where reset_id is the reset specifier from the device's resets
+property.
+
+ if (BIT(reset_id) & mask)
+ regmap[offset][reset_id] = assert-high;
+
+Required properties:
+- compatible: should contain "syscon-reset"
+- #reset-cells: must be 1
+- regmap: this is phandle to the register map node
+- offset: offset in the register map for the reboot register (in bytes)
+
+Optional properties:
+- mask: accept only the reset specifiers defined by the mask (32 bit)
+- assert-high: Bit to write when asserting a reset. Defaults to 1.
+
+Default will be little endian mode, 32 bit access only.
+
+Example:
+
+ reset-controller {
+ compatible = "syscon-reset";
+ #reset-cells = <1>;
+ regmap = <&sysctl>;
+ offset = <0x20>;
+ mask = <0x27FFFFFF>;
+ assert-high = <0>;
+ };