linux/Documentation/devicetree/bindings/memory-controllers/ti,gpmc.yaml

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/memory-controllers/ti,gpmc.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Texas Instruments GPMC Memory Controller device-tree bindings

maintainers:
  - Tony Lindgren <tony@atomide.com>
  - Roger Quadros <rogerq@kernel.org>

description:
  The GPMC is a unified memory controller dedicated for interfacing
  with external memory devices like
  - Asynchronous SRAM-like memories and ASICs
  - Asynchronous, synchronous, and page mode burst NOR flash
  - NAND flash
  - Pseudo-SRAM devices

properties:
  compatible:
    items:
      - enum:
          - ti,am3352-gpmc
          - ti,am64-gpmc
          - ti,omap2420-gpmc
          - ti,omap2430-gpmc
          - ti,omap3430-gpmc
          - ti,omap4430-gpmc

  reg:
    minItems: 1
    maxItems: 2

  reg-names:
    items:
      - const: cfg
      - const: data

  interrupts:
    maxItems: 1

  clocks:
    maxItems: 1
    description: |
      Functional clock. Used for bus timing calculations and
      GPMC configuration.      

  clock-names:
    items:
      - const: fck

  power-domains:
    maxItems: 1

  dmas:
    items:
      - description: DMA channel for GPMC NAND prefetch

  dma-names:
    items:
      - const: rxtx

  "#address-cells": true

  "#size-cells": true

  gpmc,num-cs:
    description: maximum number of supported chip-select lines.
    $ref: /schemas/types.yaml#/definitions/uint32

  gpmc,num-waitpins:
    description: maximum number of supported wait pins.
    $ref: /schemas/types.yaml#/definitions/uint32

  ranges:
    minItems: 1
    description: |
      Must be set up to reflect the memory layout with four
      integer values for each chip-select line in use,
      <cs-number> 0 <physical address of mapping> <size>      
    items:
      - description: NAND bank 0
      - description: NOR/SRAM bank 0
      - description: NOR/SRAM bank 1

  '#interrupt-cells':
    const: 2

  interrupt-controller:
    description: |
      The GPMC driver implements and interrupt controller for
      the NAND events "fifoevent" and "termcount" plus the
      rising/falling edges on the GPMC_WAIT pins.
      The interrupt number mapping is as follows
      0 - NAND_fifoevent
      1 - NAND_termcount
      2 - GPMC_WAIT0 pin edge
      3 - GPMC_WAIT1 pin edge, and so on.      

  '#gpio-cells':
    const: 2

  gpio-controller:
    description: |
      The GPMC driver implements a GPIO controller for the
      GPMC WAIT pins that can be used as general purpose inputs.
      0 maps to GPMC_WAIT0 pin.      

  ti,hwmods:
    description:
      Name of the HWMOD associated with GPMC. This is for legacy
      omap2/3 platforms only.
    $ref: /schemas/types.yaml#/definitions/string
    deprecated: true

  ti,no-idle-on-init:
    description:
      Prevent idling the module at init. This is for legacy omap2/3
      platforms only.
    type: boolean
    deprecated: true

patternProperties:
  "@[0-7],[a-f0-9]+$":
    type: object
    description: |
      The child device node represents the device connected to the GPMC
      bus. The device can be a NAND chip, SRAM device, NOR device
      or an ASIC.      
    $ref: "ti,gpmc-child.yaml"


required:
  - compatible
  - reg
  - gpmc,num-cs
  - gpmc,num-waitpins
  - "#address-cells"
  - "#size-cells"

allOf:
  - if:
      properties:
        compatible:
          contains:
            const: ti,am64-gpmc
    then:
      required:
        - reg-names
        - power-domains

additionalProperties: false

examples:
  - |
    #include <dt-bindings/interrupt-controller/arm-gic.h>
    #include <dt-bindings/gpio/gpio.h>

    gpmc: memory-controller@50000000 {
      compatible = "ti,am3352-gpmc";
      reg = <0x50000000 0x2000>;
      interrupts = <100>;
      clocks = <&l3s_clkctrl>;
      clock-names = "fck";
      dmas = <&edma 52 0>;
      dma-names = "rxtx";
      gpmc,num-cs = <8>;
      gpmc,num-waitpins = <2>;
      #address-cells = <2>;
      #size-cells = <1>;
      ranges = <0 0 0x08000000 0x10000000>; /* CS0 @addr 0x8000000, size 0x10000000 */
      interrupt-controller;
      #interrupt-cells = <2>;
      gpio-controller;
      #gpio-cells = <2>;

      nand@0,0 {
        compatible = "ti,omap2-nand";
        reg = <0 0 4>;
        interrupt-parent = <&gpmc>;
        interrupts = <0 IRQ_TYPE_NONE>, /* fifoevent */
                     <1 IRQ_TYPE_NONE>; /* termcount */
        ti,nand-xfer-type = "prefetch-dma";
        ti,nand-ecc-opt = "bch16";
        ti,elm-id = <&elm>;
        rb-gpios = <&gpmc 0 GPIO_ACTIVE_HIGH>; /* gpmc_wait0 pin */
      };
    };