Add DT binding documentation for the Linux driver for the SiFive PRCI clock & reset control IP block, as found on the SiFive FU540 chip.
Cc: Michael Turquette <mturque...@baylibre.com> Cc: Stephen Boyd <sb...@kernel.org> Cc: Rob Herring <robh...@kernel.org> Cc: Mark Rutland <mark.rutl...@arm.com> Cc: Palmer Dabbelt <pal...@sifive.com> Cc: Megan Wachs <me...@sifive.com> Cc: linux-...@vger.kernel.org Cc: devicet...@vger.kernel.org Cc: linux-ri...@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Paul Walmsley <paul.walms...@sifive.com> Signed-off-by: Paul Walmsley <p...@pwsan.com> --- .../bindings/clock/sifive/fu540-prci.txt | 40 +++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 Documentation/devicetree/bindings/clock/sifive/fu540-prci.txt diff --git a/Documentation/devicetree/bindings/clock/sifive/fu540-prci.txt b/Documentation/devicetree/bindings/clock/sifive/fu540-prci.txt new file mode 100644 index 000000000000..27d8fdd4f3a2 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/sifive/fu540-prci.txt @@ -0,0 +1,40 @@ +SiFive FU540 PRCI bindings + +On the FU540 family of SoCs, most system-wide clock and reset integration +is via the PRCI IP block. + +Required properties: +- compatible: Should be "sifive,fu540-c000-prci0" +- reg: Should describe the PRCI's register target physical address region +- clocks: Should point to the hfclk device tree node and the rtcclk + device tree node. The RTC clock here is not a time-of-day clock, + but is instead a high-stability clock source for system timers + and cycle counters. +- #clock-cells: Should be <1> + +The clock consumer should specify the desired clock via the clock ID +macros defined in include/linux/clk/sifive-fu540-prci.h. These macros +begin with PRCI_CLK_. + + + +Examples: + +hfclk: hfclk { + #clock-cells = <0>; + compatible = "fixed-clock"; + clock-frequency = <33333333>; + clock-output-names = "hfclk"; +}; +rtcclk: rtcclk { + #clock-cells = <0>; + compatible = "fixed-clock"; + clock-frequency = <1000000>; + clock-output-names = "rtcclk"; +}; +prci0: prci@10000000 { + compatible = "sifive,fu540-c000-prci0", "sifive,prci0"; + reg = <0x0 0x10000000 0x0 0x1000>; + clocks = <&hfclk>, <&rtcclk>; + #clock-cells = <1>; +}; -- 2.19.1