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diff --git a/static/freebsd/man4/at45d.4 b/static/freebsd/man4/at45d.4 new file mode 100644 index 00000000..3b49f5cf --- /dev/null +++ b/static/freebsd/man4/at45d.4 @@ -0,0 +1,182 @@ +.\" +.\" Copyright (c) 2019 Ian Lepore <ian@freebsd.org> +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR +.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES +.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. +.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, +.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT +.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF +.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +.\" +.Dd March 2, 2019 +.Dt AT45D 4 +.Os +.Sh NAME +.Nm at45d +.Nd driver for DataFlash(tm) non-volatile storage devices +.Sh SYNOPSIS +To compile this driver into the kernel, +place the following line in your +kernel configuration file: +.Bd -ragged -offset indent +.Cd "device at45d" +.Ed +.Pp +Alternatively, to load the driver as a +module at boot time, place the following line in +.Xr loader.conf 5 : +.Bd -literal -offset indent +at45d_load="YES" +.Ed +.Sh DESCRIPTION +The +.Nm +driver provides support for the family of non-volatile storage +devices known collectively as DataFlash(tm). +DataFlash chips typically have part numbers beginning with AT45DB. +The +.Nm +driver supports only the SPI bus versions of each AT45DB device, +indicated by the last digit of the part number being 1 or 2. +.Pp +The +.Nm +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 +.Nm +driver creates a disk device and makes it accessible at +.Pa /dev/flash/at45d? . +The new disk device is then tasted by the available +.Xr geom 4 +modules as with any disk device. +.Sh HARDWARE +The +.Nm +driver provides support for the following devices: +.Pp +.Bl -bullet -compact +.It +AT45DB011B +.It +AT45DB021B +.It +AT45DB041x +.It +AT45DB081B +.It +AT45DB161x +.It +AT45DB321x +.It +AT45DB321x +.It +AT45DB641E +.It +AT45DB642x +.El +.Sh FDT CONFIGURATION +On an +.Xr fdt 4 +based system, the +.Nm +device is defined as a slave device subnode +of the SPI bus controller node. +All properties documented in the +.Va spibus.txt +bindings document can be used with the +.Nm +device. +The most commonly-used ones are documented below. +.Pp +The following properties are required in the +.Nm +device subnode: +.Bl -tag -width indent +.It Va compatible +Must be the string "atmel,at45". +.It Va reg +Chip select address of device. +.It Va 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. +.El +.Pp +The following properties are optional for the +.Nm +device subnode: +.Bl -tag -width indent +.It Va freebsd,sectorsize +The sector size of the disk created for this storage device. +It must be a multiple of the device's page size. +The default is the device page size. +.It Va spi-cpha +Empty property indicating the slave device requires shifted clock +phase (CPHA) mode. +.It Va spi-cpol +Empty property indicating the slave device requires inverse clock +polarity (CPOL) mode. +.It Va spi-cs-high +Empty property indicating the slave device requires chip select active high. +.El +.Sh HINTS CONFIGURATION +On a +.Xr device.hints 5 +based system, such as +.Li MIPS , +these values are configurable for +.Nm : +.Bl -tag -width indent +.It Va hint.at45d.%d.at +The spibus the +.Nm +instance is attached to. +.It Va hint.at45d.%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. +.It Va hint.at45d.%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. +.It Va hint.at45d.%d.mode +The SPI mode (0-3) to use when communicating with this device. +.It Va hint.at45d.%d.sectorsize +The sector size of the disk created for this storage device. +It must be a multiple of the device's page size. +The default is the device page size. +.El +.Sh FILES +.Bl -tag -width /dev/flash/at45d? +.It Pa /dev/flash/at45d? +Provides read/write access to the storage device. +.It Pa /dev/flash/spi? +An alias for the +.Pa /dev/at45d? +device, for backwards compatibility with older versions of the driver. +.El +.Sh SEE ALSO +.Xr fdt 4 , +.Xr geom 4 +.Sh HISTORY +The +.Nm +driver first appeared in +.Fx 6.0 . |