linux/Documentation/devicetree/bindings/clock/keystone-pll.txt
Murali Karicheri 02fdfd708f clk: keystone: add support for post divider register for main pll
Main PLL controller has post divider bits in a separate register in
pll controller. Use the value from this register instead of fixed
divider when available.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
2015-06-18 15:36:33 -07:00

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Status: Unstable - ABI compatibility may be broken in the future
Binding for keystone PLLs. The main PLL IP typically has a multiplier,
a divider and a post divider. The additional PLL IPs like ARMPLL, DDRPLL
and PAPLL are controlled by the memory mapped register where as the Main
PLL is controlled by a PLL controller registers along with memory mapped
registers.
This binding uses the common clock binding[1].
[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
Required properties:
- #clock-cells : from common clock binding; shall be set to 0.
- compatible : shall be "ti,keystone,main-pll-clock" or "ti,keystone,pll-clock"
- clocks : parent clock phandle
- reg - pll control0 and pll multipler registers
- reg-names : control, multiplier and post-divider. The multiplier and
post-divider registers are applicable only for main pll clock
- fixed-postdiv : fixed post divider value. If absent, use clkod register bits
for postdiv
Example:
mainpllclk: mainpllclk@2310110 {
#clock-cells = <0>;
compatible = "ti,keystone,main-pll-clock";
clocks = <&refclksys>;
reg = <0x02620350 4>, <0x02310110 4>, <0x02310108 4>;
reg-names = "control", "multiplier", "post-divider";
fixed-postdiv = <2>;
};
papllclk: papllclk@2620358 {
#clock-cells = <0>;
compatible = "ti,keystone,pll-clock";
clocks = <&refclkpass>;
clock-output-names = "pa-pll-clk";
reg = <0x02620358 4>;
reg-names = "control";
};
Required properties:
- #clock-cells : from common clock binding; shall be set to 0.
- compatible : shall be "ti,keystone,pll-mux-clock"
- clocks : link phandles of parent clocks
- reg - pll mux register
- bit-shift : number of bits to shift the bit-mask
- bit-mask : arbitrary bitmask for programming the mux
Optional properties:
- clock-output-names : From common clock binding.
Example:
mainmuxclk: mainmuxclk@2310108 {
#clock-cells = <0>;
compatible = "ti,keystone,pll-mux-clock";
clocks = <&mainpllclk>, <&refclkmain>;
reg = <0x02310108 4>;
bit-shift = <23>;
bit-mask = <1>;
clock-output-names = "mainmuxclk";
};
Required properties:
- #clock-cells : from common clock binding; shall be set to 0.
- compatible : shall be "ti,keystone,pll-divider-clock"
- clocks : parent clock phandle
- reg - pll mux register
- bit-shift : number of bits to shift the bit-mask
- bit-mask : arbitrary bitmask for programming the divider
Optional properties:
- clock-output-names : From common clock binding.
Example:
gemtraceclk: gemtraceclk@2310120 {
#clock-cells = <0>;
compatible = "ti,keystone,pll-divider-clock";
clocks = <&mainmuxclk>;
reg = <0x02310120 4>;
bit-shift = <0>;
bit-mask = <8>;
clock-output-names = "gemtraceclk";
};