1# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2
3%YAML 1.2
4---
5$id: http://devicetree.org/schemas/pwm/microchip,corepwm.yaml#
6$schema: http://devicetree.org/meta-schemas/core.yaml#
7
8title: Microchip IP corePWM controller bindings
9
10maintainers:
11  - Conor Dooley <conor.dooley@microchip.com>
12
13description: |
14  corePWM is an 16 channel pulse width modulator FPGA IP
15
16  https://www.microsemi.com/existing-parts/parts/152118
17
18allOf:
19  - $ref: pwm.yaml#
20
21properties:
22  compatible:
23    items:
24      - const: microchip,corepwm-rtl-v4
25
26  reg:
27    maxItems: 1
28
29  clocks:
30    maxItems: 1
31
32  "#pwm-cells":
33    const: 2
34
35  microchip,sync-update-mask:
36    description: |
37      Depending on how the IP is instantiated, there are two modes of operation.
38      In synchronous mode, all channels are updated at the beginning of the PWM period,
39      and in asynchronous mode updates happen as the control registers are written.
40      A 16 bit wide "SHADOW_REG_EN" parameter of the IP core controls whether synchronous
41      mode is possible for each channel, and is set by the bitstream programmed to the
42      FPGA. If the IP core is instantiated with SHADOW_REG_ENx=1, both registers that
43      control the duty cycle for channel x have a second "shadow"/buffer reg synthesised.
44      At runtime a bit wide register exposed to APB can be used to toggle on/off
45      synchronised mode for all channels it has been synthesised for.
46      Each bit of "microchip,sync-update-mask" corresponds to a PWM channel & represents
47      whether synchronous mode is possible for the PWM channel.
48
49    $ref: /schemas/types.yaml#/definitions/uint32
50    default: 0
51
52  microchip,dac-mode-mask:
53    description: |
54      Optional, per-channel Low Ripple DAC mode is possible on this IP core. It creates
55      a minimum period pulse train whose High/Low average is that of the chosen duty
56      cycle. This "DAC" will have far better bandwidth and ripple performance than the
57      standard PWM algorithm can achieve. A 16 bit DAC_MODE module parameter of the IP
58      core, set at instantiation and by the bitstream programmed to the FPGA, determines
59      whether a given channel operates in regular PWM or DAC mode.
60      Each bit corresponds to a PWM channel & represents whether DAC mode is enabled
61      for that channel.
62
63    $ref: /schemas/types.yaml#/definitions/uint32
64    default: 0
65
66required:
67  - compatible
68  - reg
69  - clocks
70
71additionalProperties: false
72
73examples:
74  - |
75    pwm@41000000 {
76      compatible = "microchip,corepwm-rtl-v4";
77      microchip,sync-update-mask = /bits/ 32 <0>;
78      clocks = <&clkcfg 30>;
79      reg = <0x41000000 0xF0>;
80      #pwm-cells = <2>;
81    };
82