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# SPDX-License-Identifier: GPL-2.0-only
%YAML 1.2
---
$id: http://devicetree.org/schemas/mtd/jedec,spi-nor.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: SPI NOR flash ST M25Pxx (and similar) serial flash chips
maintainers:
- Rob Herring <robh@kernel.org>
allOf:
- $ref: mtd.yaml#
- $ref: /schemas/spi/spi-peripheral-props.yaml#
properties:
compatible:
oneOf:
- items:
- pattern: "^((((micron|spansion|st),)?\
(m25p(40|80|16|32|64|128)|\
n25q(32b|064|128a11|128a13|256a|512a|164k)))|\
atmel,at25df(321a|641|081a)|\
everspin,mr25h(10|40|128|256)|\
(mxicy|macronix),mx25l(4005a|1606e|6405d|8005|12805d|25635e)|\
(mxicy|macronix),mx25u(4033|4035)|\
(spansion,)?s25fl(128s|256s1|512s|008k|064k|164k)|\
(sst|microchip),sst25vf(016b|032b|040b)|\
(sst,)?sst26wf016b|\
(sst,)?sst25wf(040b|080)|\
winbond,w25x(80|32)|\
(winbond,)?w25q(16|32(w|dw)?|64(dw)?|80bl|128(fw)?|256))$"
- const: jedec,spi-nor
- items:
- enum:
- issi,is25lp016d
- micron,mt25qu02g
- mxicy,mx25r1635f
- mxicy,mx25u6435f
- mxicy,mx25v8035f
- spansion,s25sl12801
- spansion,s25fs512s
- const: jedec,spi-nor
- const: jedec,spi-nor
description:
SPI NOR flashes compatible with the JEDEC SFDP standard or which may be
identified with the READ ID opcode (0x9F) do not deserve a specific
compatible. They should instead only be matched against the generic
"jedec,spi-nor" compatible.
reg:
minItems: 1
maxItems: 2
m25p,fast-read:
type: boolean
description:
Use the "fast read" opcode to read data from the chip instead of the usual
"read" opcode. This opcode is not supported by all chips and support for
it can not be detected at runtime. Refer to your chips' datasheet to check
if this is supported by your chip.
broken-flash-reset:
type: boolean
description:
Some flash devices utilize stateful addressing modes (e.g., for 32-bit
addressing) which need to be managed carefully by a system. Because these
sorts of flash don't have a standardized software reset command, and
because some systems don't toggle the flash RESET# pin upon system reset
(if the pin even exists at all), there are systems which cannot reboot
properly if the flash is left in the "wrong" state. This boolean flag can
be used on such systems, to denote the absence of a reliable reset
mechanism.
no-wp:
type: boolean
description:
The status register write disable (SRWD) bit in status register, combined
with the WP# signal, provides hardware data protection for the device. When
the SRWD bit is set to 1, and the WP# signal is either driven LOW or hard
strapped to LOW, the status register nonvolatile bits become read-only and
the WRITE STATUS REGISTER operation will not execute. The only way to exit
this hardware-protected mode is to drive WP# HIGH. If the WP# signal of the
flash device is not connected or is wrongly tied to GND (that includes internal
pull-downs) then status register permanently becomes read-only as the SRWD bit
cannot be reset. This boolean flag can be used on such systems to avoid setting
the SRWD bit while writing the status register. WP# signal hard strapped to GND
can be a valid use case.
reset-gpios:
description:
A GPIO line connected to the RESET (active low) signal of the device.
If "broken-flash-reset" is present then having this property does not
make any difference.
spi-cpol: true
spi-cpha: true
dependencies:
spi-cpol: [ spi-cpha ]
spi-cpha: [ spi-cpol ]
unevaluatedProperties: false
examples:
- |
#include <dt-bindings/gpio/gpio.h>
spi {
#address-cells = <1>;
#size-cells = <0>;
flash@0 {
compatible = "spansion,m25p80", "jedec,spi-nor";
reg = <0>;
spi-max-frequency = <40000000>;
m25p,fast-read;
reset-gpios = <&gpio 12 GPIO_ACTIVE_LOW>;
};
};
...
|
