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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
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Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+Binding for TI divider clock
+
+Binding status: Unstable - ABI compatibility may be broken in the future
+
+This binding uses the common clock binding[1]. It assumes a
+register-mapped adjustable clock rate divider that does not gate and has
+only one input clock or parent. By default the value programmed into
+the register is one less than the actual divisor value. E.g:
+
+register value actual divisor value
+0 1
+1 2
+2 3
+
+This assumption may be modified by the following optional properties:
+
+ti,index-starts-at-one - valid divisor values start at 1, not the default
+of 0. E.g:
+register value actual divisor value
+1 1
+2 2
+3 3
+
+ti,index-power-of-two - valid divisor values are powers of two. E.g:
+register value actual divisor value
+0 1
+1 2
+2 4
+
+Additionally an array of valid dividers may be supplied like so:
+
+ ti,dividers = <4>, <8>, <0>, <16>;
+
+Which will map the resulting values to a divisor table by their index:
+register value actual divisor value
+0 4
+1 8
+2 <invalid divisor, skipped>
+3 16
+
+Any zero value in this array means the corresponding bit-value is invalid
+and must not be used.
+
+The binding must also provide the register to control the divider and
+unless the divider array is provided, min and max dividers. Optionally
+the number of bits to shift that mask, if necessary. If the shift value
+is missing it is the same as supplying a zero shift.
+
+This binding can also optionally provide support to the hardware autoidle
+feature, see [2].
+
+[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+[2] Documentation/devicetree/bindings/clock/ti/autoidle.txt
+
+Required properties:
+- compatible : shall be "ti,divider-clock" or "ti,composite-divider-clock".
+- #clock-cells : from common clock binding; shall be set to 0.
+- clocks : link to phandle of parent clock
+- reg : offset for register controlling adjustable divider
+
+Optional properties:
+- clock-output-names : from common clock binding.
+- ti,dividers : array of integers defining divisors
+- ti,bit-shift : number of bits to shift the divider value, defaults to 0
+- ti,min-div : min divisor for dividing the input clock rate, only
+ needed if the first divisor is offset from the default value (1)
+- ti,max-div : max divisor for dividing the input clock rate, only needed
+ if ti,dividers is not defined.
+- ti,index-starts-at-one : valid divisor programming starts at 1, not zero,
+ only valid if ti,dividers is not defined.
+- ti,index-power-of-two : valid divisor programming must be a power of two,
+ only valid if ti,dividers is not defined.
+- ti,autoidle-shift : bit shift of the autoidle enable bit for the clock,
+ see [2]
+- ti,invert-autoidle-bit : autoidle is enabled by setting the bit to 0,
+ see [2]
+- ti,set-rate-parent : clk_set_rate is propagated to parent
+- ti,latch-bit : latch the divider value to HW, only needed if the register
+ access requires this. As an example dra76x DPLL_GMAC H14 divider implements
+ such behavior.
+
+Examples:
+dpll_usb_m2_ck: dpll_usb_m2_ck@4a008190 {
+ #clock-cells = <0>;
+ compatible = "ti,divider-clock";
+ clocks = <&dpll_usb_ck>;
+ ti,max-div = <127>;
+ reg = <0x190>;
+ ti,index-starts-at-one;
+};
+
+aess_fclk: aess_fclk@4a004528 {
+ #clock-cells = <0>;
+ compatible = "ti,divider-clock";
+ clocks = <&abe_clk>;
+ ti,bit-shift = <24>;
+ reg = <0x528>;
+ ti,max-div = <2>;
+};
+
+dpll_core_m3x2_div_ck: dpll_core_m3x2_div_ck {
+ #clock-cells = <0>;
+ compatible = "ti,composite-divider-clock";
+ clocks = <&dpll_core_x2_ck>;
+ ti,max-div = <31>;
+ reg = <0x0134>;
+ ti,index-starts-at-one;
+};
+
+ssi_ssr_div_fck_3430es2: ssi_ssr_div_fck_3430es2 {
+ #clock-cells = <0>;
+ compatible = "ti,composite-divider-clock";
+ clocks = <&corex2_fck>;
+ ti,bit-shift = <8>;
+ reg = <0x0a40>;
+ ti,dividers = <0>, <1>, <2>, <3>, <4>, <0>, <6>, <0>, <8>;
+};