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MX25L(4) FreeBSD Kernel Interfaces Manual MX25L(4)
NAME
mx25l - driver for SpiFlash(tm) compatible non-volatile storage devices
SYNOPSIS
To compile this driver into the kernel, place the following line in your
kernel configuration file:
device mx25l
Alternatively, to load the driver as a module at boot time, place the
following line in loader.conf(5):
mx25l_load="YES"
DESCRIPTION
The mx25l driver provides support for the family of non-volatile storage
devices known collectively as SpiFlash(tm). SpiFlash chips typically
have part numbers beginning with EN25, IS25, MX25, S25, SST25, or W25.
The mx25l driver uses opcode 0x9f to read the manufacturer and device ID
data to determine whether the device is supported. The device ID is
looked up using a table of data within the driver which describes the
attributes of each supported device, such as block size, sector size, and
device capacity. When a supported device is found, the mx25l driver
creates a disk device and makes it accessible at /dev/flash/mx25l?. The
new disk device is then tasted by the available geom(4) modules as with
any disk device.
HARDWARE
The mx25l driver provides support for the following devices:
o AT25DF641
o EN25F32
o EN25P32
o EN25P64
o EN25Q32
o EN25Q64
o GD25Q64
o M25P32
o M25P64
o MX25L1606E
o MX25LL128
o MX25LL256
o MX25LL32
o MX25LL64
o S25FL032
o S25FL064
o S25FL128
o S25FL256S
o SST25VF010A
o SST25VF032B
o W25Q128
o W25Q256
o W25Q32
o W25Q64
o W25Q64BV
o W25X32
The following properties are required in the mx25l device subnode:
compatible
Must be the string "jedec,spi-nor".
reg Chip select address of device.
spi-max-frequency
The maximum bus frequency to use when communicating with this
slave device. Actual bus speed may be lower, depending on the
capabilities of the SPI bus controller hardware.
The following properties are optional for the mx25l device subnode:
spi-cpha
Empty property indicating the slave device requires shifted clock
phase (CPHA) mode.
spi-cpol
Empty property indicating the slave device requires inverse clock
polarity (CPOL) mode.
spi-cs-high
Empty property indicating the slave device requires chip select
active high.
HINTS CONFIGURATION
On a device.hints(5) based system, such as MIPS, these values are
configurable for mx25l:
hint.mx25l.%d.at
The spibus the mx25l instance is attached to.
hint.mx25l.%d.clock
The maximum bus frequency to use when communicating with this
device. Actual bus speed may be lower, depending on the
capabilities of the SPI bus controller hardware.
hint.mx25l.%d.cs
The chip-select number to assert when performing I/O for this
device. Set the high bit (1 << 31) to invert the logic level of
the chip select line.
hint.mx25l.%d.mode
The SPI mode (0-3) to use when communicating with this device.
FILES
/dev/flash/mx25l? Provides read/write access to the storage device.
/dev/flash/spi? An alias for the /dev/mx25l? device, for backwards
compatibility with older versions of the driver.
SEE ALSO
fdt(4), geom(4)
HISTORY
The mx25l driver first appeared in FreeBSD 8.0.