Staging
v0.7.0
v0.7.0
https://github.com/torvalds/linux
Tip revision: a7904a538933c525096ca2ccde1e60d0ee62c08e authored by Linus Torvalds on 19 December 2021, 22:14:33 UTC
Linux 5.16-rc6
Linux 5.16-rc6
Tip revision: a7904a5
mtd-physmap.yaml
# SPDX-License-Identifier: GPL-2.0
%YAML 1.2
---
$id: http://devicetree.org/schemas/mtd/mtd-physmap.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: CFI or JEDEC memory-mapped NOR flash, MTD-RAM (NVRAM...)
maintainers:
- Rob Herring <robh@kernel.org>
description: |
Flash chips (Memory Technology Devices) are often used for solid state
file systems on embedded devices.
properties:
compatible:
oneOf:
- items:
- enum:
- amd,s29gl01gp
- amd,s29gl032a
- amd,s29gl256n
- amd,s29gl512n
- arm,versatile-flash
- arm,vexpress-flash
- cortina,gemini-flash
- cypress,hyperflash
- ge,imp3a-firmware-mirror
- ge,imp3a-paged-flash
- gef,ppc9a-firmware-mirror
- gef,ppc9a-paged-flash
- gef,sbc310-firmware-mirror
- gef,sbc310-paged-flash
- gef,sbc610-firmware-mirror
- gef,sbc610-paged-flash
- intel,28f128j3
- intel,dt28f160
- intel,ixp4xx-flash
- intel,JS28F128
- intel,JS28F640
- intel,PC28F640P30T85
- numonyx,js28f00a
- numonyx,js28f128
- sst,sst39vf320
- xlnx,xps-mch-emc-2.00.a
- const: cfi-flash
- items:
- enum:
- cypress,cy7c1019dv33-10zsxi
- arm,vexpress-psram
- const: mtd-ram
- enum:
- cfi-flash
- jedec-flash
- mtd-ram
- mtd-rom
reg:
description: |
It's possible to (optionally) define multiple "reg" tuples so that
non-identical chips can be described in one node.
minItems: 1
maxItems: 8
bank-width:
description: Width (in bytes) of the bank. Equal to the device width times
the number of interleaved chips.
$ref: /schemas/types.yaml#/definitions/uint32
enum: [ 1, 2, 4 ]
device-width:
description:
Width of a single mtd chip. If omitted, assumed to be equal to 'bank-width'.
$ref: /schemas/types.yaml#/definitions/uint32
enum: [ 1, 2 ]
no-unaligned-direct-access:
type: boolean
description: |
Disables the default direct mapping of the flash.
On some platforms (e.g. MPC5200) a direct 1:1 mapping may cause problems
with JFFS2 usage, as the local bus (LPB) doesn't support unaligned
accesses as implemented in the JFFS2 code via memcpy(). By defining
"no-unaligned-direct-access", the flash will not be exposed directly to
the MTD users (e.g. JFFS2) any more.
linux,mtd-name:
description:
Allows specifying the mtd name for retro capability with physmap-flash
drivers as boot loader pass the mtd partition via the old device name
physmap-flash.
$ref: /schemas/types.yaml#/definitions/string
use-advanced-sector-protection:
type: boolean
description: |
Enables support for the advanced sector protection (Spansion: PPB -
Persistent Protection Bits) locking.
erase-size:
description: The chip's physical erase block size in bytes.
$ref: /schemas/types.yaml#/definitions/uint32
addr-gpios:
description:
List of GPIO descriptors that will be used to address the MSBs address
lines. The order goes from LSB to MSB.
minItems: 1
maxItems: 8
'#address-cells':
const: 1
'#size-cells':
const: 1
big-endian: true
little-endian: true
patternProperties:
'@[0-9a-f]+$':
$ref: partitions/partition.yaml
required:
- compatible
- reg
# FIXME: A parent bus may define timing properties
additionalProperties: true
examples:
- |
flash@ff000000 {
compatible = "cfi-flash";
reg = <0xff000000 0x01000000>;
bank-width = <4>;
device-width = <1>;
#address-cells = <1>;
#size-cells = <1>;
ranges = <0 0xff000000 0x01000000>;
fs@0 {
label = "fs";
reg = <0 0xf80000>;
};
firmware@f80000 {
label ="firmware";
reg = <0xf80000 0x80000>;
read-only;
};
};
- |
/* An example with multiple "reg" tuples */
flash@0 {
compatible = "intel,PC28F640P30T85", "cfi-flash";
reg = <0x00000000 0x02000000>,
<0x02000000 0x02000000>;
bank-width = <2>;
#address-cells = <1>;
#size-cells = <1>;
ranges = <0 0 0x04000000>;
partition@0 {
label = "test-part1";
reg = <0 0x04000000>;
};
};
- |
/* An example using SRAM */
bus {
#address-cells = <2>;
#size-cells = <1>;
sram@2,0 {
compatible = "mtd-ram";
reg = <2 0 0x00200000>;
bank-width = <2>;
};
};
- |
/* An example using addr-gpios */
#include <dt-bindings/gpio/gpio.h>
flash@20000000 {
compatible = "cfi-flash";
reg = <0x20000000 0x02000000>;
bank-width = <2>;
addr-gpios = <&gpio1 2 GPIO_ACTIVE_HIGH>;
#address-cells = <1>;
#size-cells = <1>;
ranges = <0 0x00000000 0x02000000>,
<1 0x02000000 0x02000000>;
partition@0 {
label = "test-part1";
reg = <0 0x04000000>;
};
};
...