On Mon, Dec 14, 2015 at 03:42:05PM -0700, Joshua Henderson wrote: > From: Purna Chandra Mandal <purna.mandal@xxxxxxxxxxxxx> > > Document the devicetree bindings for the clock driver found on Microchip > PIC32 class devices. > > Signed-off-by: Purna Chandra Mandal <purna.mandal@xxxxxxxxxxxxx> > Signed-off-by: Joshua Henderson <joshua.henderson@xxxxxxxxxxxxx> > Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> A couple of nits on the example, otherwise: Acked-by: Rob Herring <robh@xxxxxxxxxx> > --- > .../devicetree/bindings/clock/microchip,pic32.txt | 256 ++++++++++++++++++++ > 1 file changed, 256 insertions(+) > create mode 100644 Documentation/devicetree/bindings/clock/microchip,pic32.txt > > diff --git a/Documentation/devicetree/bindings/clock/microchip,pic32.txt b/Documentation/devicetree/bindings/clock/microchip,pic32.txt > new file mode 100644 > index 0000000..f50c653 > --- /dev/null > +++ b/Documentation/devicetree/bindings/clock/microchip,pic32.txt > @@ -0,0 +1,256 @@ > +Binding for a Clock hardware block found on > +certain Microchip PIC32 MCU devices. > + > +Microchip SoC clocks-node consists of few oscillators, PLL, multiplexer > +and few divider nodes. > + > +We will find only the base address of the clock tree, this base > +address is common for some of the subnodes, not all. If no address is > +specified for any of subnode base address of the clock tree will be > +treated as its base. Each of subnodes follow the same common clock > +binding with some additional optional properties. > + > + clocks_node { > + reg = <>; > + > + spll_node { > + ... > + }; > + > + frcdiv_node { > + ... > + }; > + > + sysclk_mux_node { > + ... > + }; > + > + pbdiv_node { > + ... > + }; > + > + refoclk_node { > + ... > + }; > + ... > + }; > + > +This binding uses the common clock binding[1]. > + > +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt > + > +Required properties: > +- compatible : should be one of "microchip,pic32mzda-clk", > + "microchip,pic32mzda-sosc", "microchip,pic32mzda-frcdivclk", > + "microchip,pic32mzda-syspll", "microchip,pic32mzda-sysclk-v2", > + "microchip,pic32mzda-pbclk", "microchip,pic32mzda-refoclk". > +- reg : A Base address and length of the register set. > +- interrupts : source of interrupt. > + > +Optional properties (for subnodes): > +- #clock-cells: From common clock binding, should be 0. > +- microchip,clock-indices: in multiplexer node clock sources always aren't linear > + and contiguous. This property helps define clock-sources with respect to > + the mux clock node. > +- microchip,ignore-unused : ignore gate request even if the gated clock is unused. > +- microchip,status-bit-mask: bitmask for status check. This will be used to confirm > + particular operation by clock sub-node is completed. It is dependent sub-node. > +- microchip,bit-mask: enable mask, similar to microchip,status-bit-mask. > +- microchip,slew-step: enable frequency slewing(stepping) during rate change; > + applicable only to sys-clock subnode. > + > +Example: > + > +/* PIC32 specific clks */ > +pic32_clktree { > + #address-cells = <1>; > + #size-cells = <1>; > + reg = <0x1f801200 0x200>; > + compatible = "microchip,pic32mzda-clk"; > + ranges = <0 0x1f801200 0x200>; > + > + /* secondary oscillator; external input on SOSCI pin */ > + SOSC:sosc_clk { For the ones with reg property, do clock@0 instead of sosc_clk. > + #clock-cells = <0>; > + compatible = "microchip,pic32mzda-sosc"; > + clock-frequency = <32768>; > + reg = <0x000 0x10>, /* enable reg */ > + <0x1d0 0x10>; /* status reg */ > + microchip,bit-mask = <0x02>; /* enable mask */ > + microchip,status-bit-mask = <0x10>; /* status-mask*/ > + }; > + > + FRCDIV:frcdiv_clk { > + #clock-cells = <0>; > + compatible = "microchip,pic32mzda-frcdivclk"; > + clocks = <&FRC>; > + clock-output-names = "frcdiv_clk"; > + }; > + > + /* System PLL clock */ > + SYSPLL:spll_clk { > + #clock-cells = <0>; > + compatible = "microchip,pic32mzda-syspll"; > + reg = <0x020 0x10>, /* SPLL register */ > + <0x1d0 0x10>; /* CLKSTAT register */ > + clocks = <&POSC>, <&FRC>; > + clock-output-names = "sys_pll"; > + microchip,status-bit-mask = <0x80>; /* SPLLRDY */ > + }; > + > + /* system clock; mux with postdiv & slew */ > + SYSCLK:sys_clk { > + #clock-cells = <0>; > + compatible = "microchip,pic32mzda-sysclk-v2"; > + reg = <0x1c0 0x04>; /* SLEWCON */ > + clocks = <&FRCDIV>, <&SYSPLL>, <&POSC>, <&SOSC>, > + <&LPRC>, <&FRCDIV>; > + microchip,clock-indices = <0>, <1>, <2>, <4>, <5>, <7>; > + clock-output-names = "sys_clk"; > + }; > + > + /* UPLL is integral part of USB PHY; UTMI clk for USBCORE */ > + UPLL:usb_phy_clk { > + #clock-cells = <0>; > + compatible = "fixed-clocks"; > + clock-frequency = <24000000>; > + clock-output-names = "usbphy_clk"; > + }; > + > + /* Peripheral bus1 clock */ > + PBCLK1:pb1_clk { > + reg = <0x140 0x10>; > + #clock-cells = <0>; > + compatible = "microchip,pic32mzda-pbclk"; > + clocks = <&SYSCLK>; > + clock-output-names = "pb1_clk"; > + /* used by system modules, not gateable */ > + microchip,ignore-unused; > + }; > + > + /* Peripheral bus2 clock */ > + PBCLK2:pb2_clk { > + reg = <0x150 0x10>; > + #clock-cells = <0>; > + compatible = "microchip,pic32mzda-pbclk"; > + clocks = <&SYSCLK>; > + clock-output-names = "pb2_clk"; > + /* avoid gating even if unused */ > + microchip,ignore-unused; > + }; > + > + /* Peripheral bus3 clock */ > + PBCLK3:pb3_clk { > + reg = <0x160 0x10>; > + #clock-cells = <0>; > + compatible = "microchip,pic32mzda-pbclk"; > + clocks = <&SYSCLK>; > + clock-output-names = "pb3_clk"; > + }; > + > + /* Peripheral bus4 clock(I/O ports, GPIO) */ > + PBCLK4:pb4_clk { > + reg = <0x170 0x10>; > + #clock-cells = <0>; > + compatible = "microchip,pic32mzda-pbclk"; > + clocks = <&SYSCLK>; > + clock-output-names = "pb4_clk"; > + }; > + > + /* Peripheral bus clock */ > + PBCLK5:pb5_clk { > + reg = <0x180 0x10>; > + #clock-cells = <0>; > + compatible = "microchip,pic32mzda-pbclk"; > + clocks = <&SYSCLK>; > + clock-output-names = "pb5_clk"; > + }; > + > + /* Peripheral Bus6 clock; */ > + PBCLK6:pb6_clk { > + reg = <0x190 0x10>; > + compatible = "microchip,pic32mzda-pbclk"; > + clocks = <&SYSCLK>; > + #clock-cells = <0>; > + }; > + > + /* Peripheral bus7 clock */ > + PBCLK7:pb7_clk { > + reg = <0x1A0 0x10>; lower case > + #clock-cells = <0>; > + compatible = "microchip,pic32mzda-pbclk"; > + /* CPU is driven by this clock; so named */ > + clock-output-names = "cpu_clk"; > + clocks = <&SYSCLK>; > + }; > + > + /* Reference Oscillator clock for SPI/I2S */ > + REFCLKO1:refo1_clk { > + reg = <0x080 0x20>; > + #clock-cells = <0>; > + compatible = "microchip,pic32mzda-refoclk"; > + clocks = <&SYSCLK>, <&PBCLK1>, <&POSC>, <&FRC>, <&LPRC>, > + <&SOSC>, <&SYSPLL>, <&REFIx>, <&BFRC>; > + microchip,clock-indices = <0>, <1>, <2>, <3>, <4>, <5>, > + <7>, <8>, <9>; > + clock-output-names = "refo1_clk"; > + }; > + > + /* Reference Oscillator clock for SQI */ > + REFCLKO2:refo2_clk { > + reg = <0x0A0 0x20>; lower case > + #clock-cells = <0>; > + compatible = "microchip,pic32mzda-refoclk"; > + clocks = <&SYSCLK>, <&PBCLK1>, <&POSC>, <&FRC>, <&LPRC>, > + <&SOSC>, <&SYSPLL>, <&REFIx>, <&BFRC>; > + microchip,clock-indices = <0>, <1>, <2>, <3>, <4>, <5>, > + <7>, <8>, <9>; > + clock-output-names = "refo2_clk"; > + }; > + > + /* Reference Oscillator clock, ADC */ > + REFCLKO3:refo3_clk { > + reg = <0x0C0 0x20>; lower case > + compatible = "microchip,pic32mzda-refoclk"; > + clocks = <&SYSCLK>, <&PBCLK1>, <&POSC>, <&FRC>, <&LPRC>, > + <&SOSC>, <&SYSPLL>, <&REFIx>, <&BFRC>; > + microchip,clock-indices = <0>, <1>, <2>, <3>, <4>, <5>, > + <7>, <8>, <9>; > + #clock-cells = <0>; > + clock-output-names = "refo3_clk"; > + }; > + > + /* Reference Oscillator clock */ > + REFCLKO4:refo4_clk { > + reg = <0x0E0 0x20>; > + compatible = "microchip,pic32mzda-refoclk"; > + clocks = <&SYSCLK>, <&PBCLK1>, <&POSC>, <&FRC>, <&LPRC>, > + <&SOSC>, <&SYSPLL>, <&REFIx>, <&BFRC>; > + microchip,clock-indices = <0>,<1>,<2>,<3>,<4>,<5>,<7>, > + <8>,<9>; > + #clock-cells = <0>; > + clock-output-names = "refo4_clk"; > + }; > + > + /* Reference Oscillator clock, LCD */ > + REFCLKO5:refo5_clk { > + reg = <0x100 0x20>; > + compatible = "microchip,pic32mzda-refoclk"; > + clocks = <&SYSCLK>,<&PBCLK1>,<&POSC>,<&FRC>,<&LPRC>, > + <&SOSC>,<&SYSPLL>,<&REFIx>,<&BFRC>; > + microchip,clock-indices = <0>, <1>, <2>, <3>, <4>, <5>, > + <7>, <8>,<9>; > + #clock-cells = <0>; > + clock-output-names = "refo5_clk"; > + }; > +}; > + > +The clock consumer should specify the desired clock by having the clocks in its > +"clock" phandle cell. For example for UART: > + > +uart2: serial@<> { > + compatible = "microchip,pic32mzda-uart"; > + reg = <>; > + interrupts = <>; > + clocks = <&PBCLK2>; > +} > -- > 1.7.9.5 > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html