linux-stable/Documentation/devicetree/bindings/mtd/brcm,brcmnand.yaml

# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
%YAML 1.2
---
$id: http://devicetree.org/schemas/mtd/brcm,brcmnand.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Broadcom STB NAND Controller

maintainers:
  - Brian Norris <computersforpeace@gmail.com>
  - Kamal Dasu <kdasu.kdev@gmail.com>

description: |
  The Broadcom Set-Top Box NAND controller supports low-level access to raw NAND
  flash chips. It has a memory-mapped register interface for both control
  registers and for its data input/output buffer. On some SoCs, this controller
  is paired with a custom DMA engine (inventively named "Flash DMA") which
  supports basic PROGRAM and READ functions, among other features.

  This controller was originally designed for STB SoCs (BCM7xxx) but is now
  available on a variety of Broadcom SoCs, including some BCM3xxx, BCM63xx, and
  iProc/Cygnus. Its history includes several similar (but not fully register
  compatible) versions.

  -- Additional SoC-specific NAND controller properties --

  The NAND controller is integrated differently on the variety of SoCs on which
  it is found. Part of this integration involves providing status and enable
  bits with which to control the 8 exposed NAND interrupts, as well as hardware
  for configuring the endianness of the data bus. On some SoCs, these features
  are handled via standard, modular components (e.g., their interrupts look like
  a normal IRQ chip), but on others, they are controlled in unique and
  interesting ways, sometimes with registers that lump multiple NAND-related
  functions together. The former case can be described simply by the standard
  interrupts properties in the main controller node. But for the latter
  exceptional cases, we define additional 'compatible' properties and associated
  register resources within the NAND controller node above.  

properties:
  compatible:
    oneOf:
      - items:
          - enum:
              - brcm,brcmnand-v2.1
              - brcm,brcmnand-v2.2
              - brcm,brcmnand-v4.0
              - brcm,brcmnand-v5.0
              - brcm,brcmnand-v6.0
              - brcm,brcmnand-v6.1
              - brcm,brcmnand-v6.2
              - brcm,brcmnand-v7.0
              - brcm,brcmnand-v7.1
              - brcm,brcmnand-v7.2
              - brcm,brcmnand-v7.3
          - const: brcm,brcmnand
      - description: BCM63138 SoC-specific NAND controller
        items:
          - const: brcm,nand-bcm63138
          - enum:
              - brcm,brcmnand-v7.0
              - brcm,brcmnand-v7.1
          - const: brcm,brcmnand
      - description: iProc SoC-specific NAND controller
        items:
          - const: brcm,nand-iproc
          - const: brcm,brcmnand-v6.1
          - const: brcm,brcmnand
      - description: BCM63168 SoC-specific NAND controller
        items:
          - const: brcm,nand-bcm63168
          - const: brcm,nand-bcm6368
          - const: brcm,brcmnand-v4.0
          - const: brcm,brcmnand

  reg:
    minItems: 1
    maxItems: 6

  reg-names:
    minItems: 1
    maxItems: 6
    items:
      enum: [ nand, flash-dma, flash-edu, nand-cache, nand-int-base, iproc-idm, iproc-ext ]

  interrupts:
    minItems: 1
    items:
      - description: NAND CTLRDY interrupt
      - description: FLASH_DMA_DONE (if flash DMA is available) or FLASH_EDU_DONE (if EDU is available)

  interrupt-names:
    minItems: 1
    items:
      - const: nand_ctlrdy
      - enum:
          - flash_dma_done
          - flash_edu_done

  clocks:
    maxItems: 1
    description: reference to the clock for the NAND controller

  clock-names:
    const: nand

  brcm,nand-has-wp:
    description: >
      Some versions of this IP include a write-protect
      (WP) control bit. It is always available on >=
      v7.0. Use this property to describe the rare
      earlier versions of this core that include WP      
    type: boolean

patternProperties:
  "^nand@[a-f0-9]$":
    type: object
    properties:
      compatible:
        const: brcm,nandcs

      nand-ecc-step-size:
        enum: [ 512, 1024 ]

      brcm,nand-oob-sector-size:
        description: |
          integer, to denote the spare area sector size
          expected for the ECC layout in use. This size, in
          addition to the strength and step-size,
          determines how the hardware BCH engine will lay
          out the parity bytes it stores on the flash.
          This property can be automatically determined by
          the flash geometry (particularly the NAND page
          and OOB size) in many cases, but when booting
          from NAND, the boot controller has only a limited
          number of available options for its default ECC
          layout.          
        $ref: /schemas/types.yaml#/definitions/uint32

allOf:
  - $ref: nand-controller.yaml#
  - if:
      properties:
        compatible:
          contains:
            const: brcm,nand-bcm63138
    then:
      properties:
        reg-names:
          items:
            - const: nand
            - const: nand-int-base
  - if:
      properties:
        compatible:
          contains:
            const: brcm,nand-bcm6368
    then:
      properties:
        reg-names:
          items:
            - const: nand
            - const: nand-int-base
            - const: nand-cache
  - if:
      properties:
        compatible:
          contains:
            const: brcm,nand-iproc
    then:
      properties:
        reg-names:
          items:
            - const: nand
            - const: iproc-idm
            - const: iproc-ext
  - if:
      properties:
        interrupts:
          minItems: 2
    then:
      required:
        - interrupt-names

unevaluatedProperties: false

required:
  - reg
  - reg-names
  - interrupts

examples:
  - |
    nand-controller@f0442800 {
        compatible = "brcm,brcmnand-v7.0", "brcm,brcmnand";
        reg = <0xf0442800 0x600>,
              <0xf0443000 0x100>;
        reg-names = "nand", "flash-dma";
        interrupt-parent = <&hif_intr2_intc>;
        interrupts = <24>, <4>;
        interrupt-names = "nand_ctlrdy", "flash_dma_done";

        #address-cells = <1>;
        #size-cells = <0>;

        nand@1 {
            compatible = "brcm,nandcs";
            reg = <1>; // Chip select 1
            nand-on-flash-bbt;
            nand-ecc-strength = <12>;
            nand-ecc-step-size = <512>;

            #address-cells = <1>;
            #size-cells = <1>;
        };
    };    
  - |
    nand-controller@10000200 {
        compatible = "brcm,nand-bcm63168", "brcm,nand-bcm6368",
                     "brcm,brcmnand-v4.0", "brcm,brcmnand";
        reg = <0x10000200 0x180>,
              <0x100000b0 0x10>,
              <0x10000600 0x200>;
        reg-names = "nand", "nand-int-base", "nand-cache";
        interrupt-parent = <&periph_intc>;
        interrupts = <50>;
        clocks = <&periph_clk 20>;
        clock-names = "nand";

        #address-cells = <1>;
        #size-cells = <0>;

        nand@0 {
            compatible = "brcm,nandcs";
            reg = <0>;
            nand-on-flash-bbt;
            nand-ecc-strength = <1>;
            nand-ecc-step-size = <512>;

            #address-cells = <1>;
            #size-cells = <1>;
        };
    };