[RFC PATCH 11/50] ARM: at91: add PMC clk device tree binding doc.
From: Boris BREZILLON
Date: Fri Jun 07 2013 - 10:43:33 EST
This is the documentation of the dt bindings used by at91 clks.
Signed-off-by: Boris BREZILLON <b.brezillon@xxxxxxxxxxx>
---
.../devicetree/bindings/clock/at91-clock.txt | 247 ++++++++++++++++++++
1 file changed, 247 insertions(+)
diff --git a/Documentation/devicetree/bindings/clock/at91-clock.txt b/Documentation/devicetree/bindings/clock/at91-clock.txt
new file mode 100644
index 0000000..63c5d16
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/at91-clock.txt
@@ -0,0 +1,247 @@
+Device Tree Clock bindings for arch-at91
+
+This binding uses the common clock binding[1].
+
+[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+
+Required properties:
+- compatible : shall be one of the following:
+ "atmel,at91rm9200-clk-main":
+ at91 main oscillator
+
+ "atmel,at91rm9200-clk-master" or
+ "atmel,at91sam9x5-clk-master":
+ at91 master clock
+
+ "atmel,at91sam9x5-clk-peripheral" or
+ "atmel,at91rm9200-clk-peripheral":
+ at91 peripheral clocks
+
+ "atmel,at91rm9200-clk-pll" or
+ "atmel,at91sam9g45-clk-pll" or
+ "atmel,at91sam9g20-clk-pllb" or
+ "atmel,sama5d3-clk-pll":
+ at91 pll clocks
+
+ "atmel,at91sam9x5-clk-plldiv":
+ at91 plla divisor
+
+ "atmel,at91rm9200-clk-programmable" or
+ "atmel,at91sam9g45-clk-programmable" or
+ "atmel,at91sam9x5-clk-programmable":
+ at91 programmable clocks
+
+ "atmel,at91sam9x5-clk-smd":
+ at91 SMD (Soft Modem) clock
+
+ "atmel,at91rm9200-clk-system":
+ at91 system clocks
+
+ "atmel,at91rm9200-clk-usb" or
+ "atmel,at91sam9x5-clk-usb":
+ at91 usb clock
+
+ "atmel,at91sam9x5-clk-utmi":
+ at91 utmi clock
+
+
+Required properties for main clock:
+- #clock-cells : from common clock binding; shall be set to 0.
+- clocks (optional if clock-frequency is provided) : shall be the slow clock
+ phandle. This clock is used to compute the main clock rate if
+ "clock-frequency" is not provided.
+- clock-frequency: the main oscillator frequency.Prefer the use of
+ "clock-frequency" over automatic clock rate computation.
+
+For example:
+ main: mainck {
+ compatible = "atmel,at91rm9200-clk-main";
+ #clock-cells = <0>;
+ clocks = <&ck32k>;
+ clock-frequency = <18432000>;
+ };
+
+Required properties for master clock:
+- #clock-cells : from common clock binding; shall be set to 0.
+- clocks : shall be the master clock sources (see atmel datasheet) phandles.
+ e.g. "<&ck32k>, <&main>, <&plla>, <&pllb>".
+- characteristics : device tree node describing master clock characteristics.
+ You can find these characteristics in atmel's SoC datasheets.
+ * output : minimum and maximum clock frequency (two u32 fields).
+ e.g. output = <0 133000000>; <=> 0 to 133MHz.
+ * divisors : master clock divisors table (four u32 fields).
+ 0 <=> reserved value.
+ e.g. divisors = <1 2 4 6>;
+ * have-div3-pres : some SoC use the reserved value 7 in the PRES field
+ as CLOCK_DIV3 (e.g sam9x5).
+
+For example:
+ mck: mck {
+ compatible = "atmel,at91rm9200-clk-master";
+ #clock-cells = <0>;
+ characteristics = {
+ output = <0 133000000>;
+ divisors = <1 2 4 0>;
+ };
+ };
+
+Required properties for peripheral clocks:
+- #clock-cells : from common clock binding; shall be set to 1. The second cell
+ is used to encode the peripheral id. Peripheral ids are defined in
+ atmel's SoC datasheets.
+- clocks : shall be the master clock phandle.
+ e.g. clocks = <&mck>;
+- ids : peripheral ids (u32 array).
+- clock-output-names : name of clocks. These are the name used during clock
+ registration.
+- "default-divisors" (optional, only available for
+ "atmel,at91sam9x5-clk-peripheral") : sam9x5 and sama5d3 SoC provides
+ configurable peripheral clock divisors. If you define this property
+ (u32 array), the default divisor will be applied when enabling
+ peripheral clock. If not provided the peripheral clock is not divided.
+
+For example:
+ periph: periphck {
+ compatible = "atmel,at91sam9x5-clk-peripheral";
+ #clock-cells = <1>;
+ clocks = <&mck>;
+ ids = <2 6 7>;
+ clock-output-names = "pioA_clk", "pioB_clk", "pioB_clk";
+ default-divisors = <1 2 2>;
+ };
+
+
+Required properties for pll clocks:
+- #clock-cells : from common clock binding; shall be set to 0.
+- clocks : shall be the main clock phandle.
+- id : pll id
+ * 0 <=> plla
+ * 1 <=> pllb
+- characteristics : device tree node describing pll clock characteristics.
+ You can find these characteristics in atmel's SoC datasheets.
+ * input : minimum and maximum source clock frequency (two u32 fields).
+ e.g. input = <1 32000000>; <=> 1 to 32MHz.
+ * output : output frequency ranges.
+ * out: out field value for output frequency ranges.
+ * icpll (not available on some SoC): icpll field value for output
+ frequency ranges.
+
+For example:
+ plla: pllack {
+ compatible = "atmel,at91sam9g45-clk-pll";
+ #clock-cells = <0>;
+ clocks = <&main>;
+ id = <0>;
+ input = <2000000 32000000>;
+ output = <74500000 800000000
+ 69500000 750000000
+ 64500000 700000000
+ 59500000 650000000
+ 54500000 600000000
+ 49500000 550000000
+ 44500000 500000000
+ 40000000 450000000>;
+ out = <0 1 2 3 0 1 2 3>;
+ icpll = <0 0 0 0 1 1 1 1>;
+ };
+
+Required properties for plldiv clocks:
+- #clock-cells : from common clock binding; shall be set to 0.
+- clocks : shall be the plla clock phandle.
+
+For example:
+ plladiv: plladivck {
+ compatible = "atmel,at91sam9x5-clk-plldiv";
+ #clock-cells = <0>;
+ clocks = <&plla>;
+ };
+
+Required properties for programmable clocks:
+- #clock-cells : from common clock binding; shall be set to 1. The second cell
+ is used to encode the programmable clock id.
+ Peripheral ids are in atmel's SoC
+ datasheets.
+- clocks : shall be the programmable clock source phandles.
+ e.g. clocks = <&clk32k>, <&main>, <&plla>, <&pllb>;
+- ids : programmable clock ids (u32 array).
+- clock-output-names : name of clocks. These names are used during clock
+ registration.
+
+For example:
+ prog: progck {
+ compatible = "atmel,at91sam9g45-clk-programmable";
+ #clock-cells = <1>;
+ ids = <0 1>;
+ clocks = <&clk32k>, <&main>, <&plladiv>, <&utmi>, <&mck>;
+ clock-output-names = "prog0", "prog1";
+ };
+
+
+Required properties for smd clock:
+- #clock-cells : from common clock binding; shall be set to 0.
+- clocks : shall be the smd clock source phandles.
+ e.g. clocks = <&plladiv>, <&utmi>;
+
+For example:
+ smd: smdck {
+ compatible = "atmel,at91sam9x5-clk-smd";
+ #clock-cells = <0>;
+ clocks = <&plladiv>, <&utmi>;
+ };
+
+Required properties for system clocks:
+- #clock-cells : from common clock binding; shall be set to 1. The second cell
+ is used to encode the system clock id (bit used in SCER/SCDR register).
+- clocks : shall be the system clock source phandle.
+ e.g. clocks = <&usb>;
+- ids : peripheral ids (u32 array).
+- clock-output-names : name of clocks. These names are used during clock
+ registration.
+
+For example:
+ system: systemck {
+ compatible = "atmel,at91rm9200-clk-system";
+ #clock-cells = <1>;
+ ids = <2 4 6 7 8 9 10>;
+ clocks = <&mck>, <&smd>, <&usb>, <&usb>,
+ <&prog 0>, <&prog 1>, <&prog 2>;
+ clock-output-names = "ddrck", "smdck", "uhpck", "udpck",
+ "pck0", "pck1", "pck2";
+ };
+
+
+Required properties for usb clock:
+- #clock-cells : from common clock binding; shall be set to 0.
+- clocks : shall be the smd clock source phandles.
+ e.g. clocks = <&pllb>;
+- divisors (only available for "atmel,at91rm9200-clk-usb"):
+ usb clock divisor table.
+ e.g. divisors = <1 2 4 0>;
+- usbs0-unused (only available for "atmel,at91sam9x5-clk-usb"):
+ Some SoC (sam9n12) use usb source 0 to disable the usb clock.
+
+For example:
+ usb: usbck {
+ compatible = "atmel,at91sam9x5-clk-usb";
+ #clock-cells = <0>;
+ clocks = <&plladiv>, <&utmi>;
+ };
+
+ usb: usbck {
+ compatible = "atmel,at91rm9200-clk-usb";
+ #clock-cells = <0>;
+ clocks = <&pllb>;
+ divisors = <1 2 4 0>;
+ };
+
+
+Required properties for utmi clock:
+- #clock-cells : from common clock binding; shall be set to 0.
+- clocks : shall be the main clock source phandle.
+
+For example:
+ utmi: utmick {
+ compatible = "atmel,at91sam9x5-clk-utmi";
+ #clock-cells = <0>;
+ clocks = <&main>;
+ };
--
1.7.9.5
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