| Message ID | 20190411082733.3736-3-paul.walmsley@sifive.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | clk: add driver for the SiFive FU540 PRCI and PLLs it controls | expand |
On Thu, 11 Apr 2019 01:27:34 -0700, Paul Walmsley wrote: > Add DT binding documentation for the Linux driver for the SiFive > PRCI clock & reset control IP block, as found on the SiFive > FU540 chip. > > This version includes changes requested by Stephen Boyd > <sboyd@kernel.org> and Rob Herring <robh@kernel.org>, and > fixes some errors in the initial version. > > Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> > Signed-off-by: Paul Walmsley <paul@pwsan.com> > Cc: Michael Turquette <mturquette@baylibre.com> > Cc: Stephen Boyd <sboyd@kernel.org> > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Mark Rutland <mark.rutland@arm.com> > Cc: Palmer Dabbelt <palmer@sifive.com> > Cc: Megan Wachs <megan@sifive.com> > Cc: linux-clk@vger.kernel.org > Cc: devicetree@vger.kernel.org > Cc: linux-riscv@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > --- > .../bindings/clock/sifive/fu540-prci.txt | 46 +++++++++++++++++++ > 1 file changed, 46 insertions(+) > create mode 100644 Documentation/devicetree/bindings/clock/sifive/fu540-prci.txt > Reviewed-by: Rob Herring <robh@kernel.org>
Quoting Paul Walmsley (2019-04-11 01:27:34) > Add DT binding documentation for the Linux driver for the SiFive > PRCI clock & reset control IP block, as found on the SiFive > FU540 chip. > > This version includes changes requested by Stephen Boyd > <sboyd@kernel.org> and Rob Herring <robh@kernel.org>, and > fixes some errors in the initial version. > > Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> > Signed-off-by: Paul Walmsley <paul@pwsan.com> > Cc: Michael Turquette <mturquette@baylibre.com> > Cc: Stephen Boyd <sboyd@kernel.org> > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Mark Rutland <mark.rutland@arm.com> > Cc: Palmer Dabbelt <palmer@sifive.com> > Cc: Megan Wachs <megan@sifive.com> > Cc: linux-clk@vger.kernel.org > Cc: devicetree@vger.kernel.org > Cc: linux-riscv@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > --- Applied to clk-next
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..349808f4fb8c --- /dev/null +++ b/Documentation/devicetree/bindings/clock/sifive/fu540-prci.txt @@ -0,0 +1,46 @@ +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,<chip>-prci". Only one value is + supported: "sifive,fu540-c000-prci" +- 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/dt-bindings/clock/sifive-fu540-prci.h. +These macros begin with PRCI_CLK_. + +The hfclk and rtcclk nodes are required, and represent physical +crystals or resonators located on the PCB. These nodes should be present +underneath /, rather than /soc. + +Examples: + +/* under /, in PCB-specific DT data */ +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"; +}; + +/* under /soc, in SoC-specific DT data */ +prci: clock-controller@10000000 { + compatible = "sifive,fu540-c000-prci"; + reg = <0x0 0x10000000 0x0 0x1000>; + clocks = <&hfclk>, <&rtcclk>; + #clock-cells = <1>; +};