nxp,imx-cguana-sxosc

Description

Crystal oscillator in an NXP i.MX CGU analog block (CGUANA).

This is the board's crystal, and the reference the PLLs lock to. Declaring it
here is what lets a board state its own crystal frequency and trim without
editing SoC or board C code.

    sxosc: sxosc {
            compatible = "nxp,imx-cguana-sxosc";
            clock-frequency = <24000000>;
            nxp,gm-sel = <4>;
            nxp,cap-trim = <16>, <16>;
            #clock-cells = <0>;
    };

Properties

Properties not inherited from the base binding file.

Name

Type

Details

nxp,mode

string

Oscillator drive mode. "crystal" drives a crystal on XTAL1/XTAL2; the
bypass modes take an external clock instead.

Default value: crystal

Legal values: crystal, ac-slave, dc-bypass, dc-bypass-no-detect

nxp,gm-sel

int

Transconductance select for the oscillator amplifier. The right value
depends on the crystal's equivalent series resistance; the reference
manual's crystal table gives a recommended value per frequency, and 3 is
the recommendation for a 24 MHz crystal.

Default value: 3

nxp,cap-trim

array

On-chip load-capacitance trim for XTAL1 and XTAL2, in that order, each
0..63. Must match the board's crystal load capacitance and stray
capacitance, and both pins normally take the same value unless the
schematic specifies an asymmetric load.

Omit it to leave the reset default. A board that supplies a value it has
not had measured should say so, because an untrimmed load shows up as a
frequency error in everything derived from this crystal.

nxp,det-trim

int

Amplitude-detector trim. Leave at 0 unless the hardware team specifies
otherwise for start-up margin.

Default value: 0

nxp,div2-enable

boolean

Halve the oscillator output. Without it the output is the crystal
frequency named in clock-frequency.

clock-frequency

int

output clock frequency (Hz)

This property is required.

#clock-cells

int

Number of items to expect in a Clock specifier

This property is required.

Constant value: 0