It supports a wide range of DIP32, PLCC32, DIP8, SO8/SOIC8, TSOP32, TSOP40, TSOP48, and BGA chips, which use various protocols such as LPC, FWH, parallel flash, or SPI.
You can specify one of -h, -R, -L, -z, -E, -r, -w, -v or no operation. If no operation is specified, flashrom will only probe for flash chips. It is recommended that if you try flashrom the first time on a system, you run it in probe-only mode and check the output. Also you are advised to make a backup of your current ROM contents with -r before you try to write a new image. All operations involving any chip access (probe/read/write/...) require the -p/--programmer option to be used (please see below).
In the process the chip is also read several times. First an in-memory backup is made for disaster recovery and to be able to skip regions that are already equal to the image file. This copy is updated along with the write operation. In case of erase errors it is even re-read completely. After writing has finished and if verification is enabled, the whole flash chip is read out and compared with the input image.
Typical usage is: flashrom -p prog -n -w <file>
This option is only useful in combination with --write.
This option is required to flash an Intel system with locked ME flash region using the internal programmer. It may be enabled by default in this case in the future.
* Force chip read and pretend the chip is there.
* Force chip access even if the chip is bigger than the maximum supported size for the flash bus.
* Force erase even if erase is known bad.
* Force write even if write is known bad.
flashrom supports ROM layouts. This allows you to flash certain parts of the flash chip only. A ROM layout file contains multiple lines with the following syntax:
startaddr:endaddr imagename
startaddr and endaddr are hexadecimal addresses within the ROM file and do not refer to any physical address. Please note that using a 0x prefix for those hexadecimal numbers is not necessary, but you can't specify decimal/octal numbers. imagename is an arbitrary name for the region/image from startaddr to endaddr (both addresses included).
Example:
00000000:00008fff gfxrom
00009000:0003ffff normal
00040000:0007ffff fallback
If you only want to update the image named normal in a ROM based on the layout above, run
flashrom -p prog --layout rom.layout --image normal -w some.rom
To update only the images named normal and fallback, run:
flashrom -p prog -l rom.layout -i normal -i fallback -w some.rom
Overlapping sections are not supported.
flashrom supports the fmap binary format which is commonly used by coreboot for partitioning a flash chip. The on-chip fmap will be read and used to generate the layout.
If you only want to update the COREBOOT region defined in the fmap, run
flashrom -p prog --fmap --image COREBOOT -w some.rom
flashrom supports the fmap binary format which is commonly used by coreboot for partitioning a flash chip. The fmap in the specified file will be read and used to generate the layout.
If you only want to update the COREBOOT region defined in the binary fmap file, run
flashrom -p prog --fmap-file some.rom --image COREBOOT -w some.rom
flashrom supports ROM layouts given by an Intel Firmware Descriptor (IFD). The on-chip descriptor will be read and used to generate the layout. If you need to change the layout, you have to update the IFD only first.
The following ROM images may be present in an IFD:
fd the IFD itself
bios the host firmware aka. BIOS
me Intel Management Engine firmware
gbe gigabit ethernet firmware
pd platform specific data
There are many unlisted boards which will work out of the box, without special support in flashrom. Please let us know if you can verify that other boards work or do not work out of the box.
IMPORTANT: For verification you have to test an ERASE and/or WRITE operation, so make sure you only do that if you have proper means to recover from failure!
* internal (for in-system flashing in the mainboard)
* dummy (virtual programmer for testing flashrom)
* nic3com (for flash ROMs on 3COM network cards)
* nicrealtek (for flash ROMs on Realtek and SMC 1211 network cards)
* nicnatsemi (for flash ROMs on National Semiconductor DP838* network cards)
* nicintel (for parallel flash ROMs on Intel 10/100Mbit network cards)
* gfxnvidia (for flash ROMs on NVIDIA graphics cards)
* drkaiser (for flash ROMs on Dr. Kaiser PC-Waechter PCI cards)
* satasii (for flash ROMs on Silicon Image SATA/IDE controllers)
* satamv (for flash ROMs on Marvell SATA controllers)
* atahpt (for flash ROMs on Highpoint ATA/RAID controllers)
* atavia (for flash ROMs on VIA VT6421A SATA controllers)
* atapromise (for flash ROMs on Promise PDC2026x ATA/RAID controllers)
* it8212 (for flash ROMs on ITE IT8212F ATA/RAID controller)
* ft2232_spi (for SPI flash ROMs attached to an FT2232/FT4232H/FT232H family based USB SPI programmer).
* serprog (for flash ROMs attached to a programmer speaking serprog, including some Arduino-based devices).
* buspirate_spi (for SPI flash ROMs attached to a Bus Pirate)
* dediprog (for SPI flash ROMs attached to a Dediprog SF100)
* rayer_spi (for SPI flash ROMs attached to a parallel port by one of various cable types)
* pony_spi (for SPI flash ROMs attached to a SI-Prog serial port bitbanging adapter)
* nicintel_spi (for SPI flash ROMs on Intel Gigabit network cards)
* ogp_spi (for SPI flash ROMs on Open Graphics Project graphics card)
* linux_mtd (for SPI flash ROMs accessible via /dev/mtdX on Linux)
* linux_spi (for SPI flash ROMs accessible via /dev/spidevX.Y on Linux)
* usbblaster_spi (for SPI flash ROMs attached to an Altera USB-Blaster compatible cable)
* nicintel_eeprom (for SPI EEPROMs on Intel Gigabit network cards)
* mstarddc_spi (for SPI flash ROMs accessible through DDC in MSTAR-equipped displays)
* pickit2_spi (for SPI flash ROMs accessible via Microchip PICkit2)
* ch341a_spi (for SPI flash ROMs attached to WCH CH341A)
* digilent_spi (for SPI flash ROMs attached to iCEblink40 development boards)
* jlink_spi (for SPI flash ROMs attached to SEGGER J-Link and compatible devices)
* ni845x_spi (for SPI flash ROMs attached to National Instruments USB-8451 or USB-8452)
* stlinkv3_spi (for SPI flash ROMs attached to STMicroelectronics STLINK V3 devices)
Some programmers have optional or mandatory parameters which are described in detail in the PROGRAMMER-SPECIFIC INFORMATION section. Support for some programmers can be disabled at compile time. flashrom -h lists all supported programmers.
Some mainboards require to run mainboard specific code to enable flash erase and write support (and probe support on old systems with parallel flash). The mainboard brand and model (if it requires specific code) is usually autodetected using one of the following mechanisms: If your system is running coreboot, the mainboard type is determined from the coreboot table. Otherwise, the mainboard is detected by examining the onboard PCI devices and possibly DMI info. If PCI and DMI do not contain information to uniquely identify the mainboard (which is the exception), or if you want to override the detected mainboard model, you can specify the mainboard using the
flashrom -p internal:mainboard=<vendor>:<board> syntax.
See the 'Known boards' or 'Known laptops' section in the output of 'flashrom -L' for a list of boards which require the specification of the board name, if no coreboot table is found.
Some of these board-specific flash enabling functions (called board enables) in flashrom have not yet been tested. If your mainboard is detected needing an untested board enable function, a warning message is printed and the board enable is not executed, because a wrong board enable function might cause the system to behave erratically, as board enable functions touch the low-level internals of a mainboard. Not executing a board enable function (if one is needed) might cause detection or erasing failure. If your board protects only part of the flash (commonly the top end, called boot block), flashrom might encounter an error only after erasing the unprotected part, so running without the board-enable function might be dangerous for erase and write (which includes erase).
The suggested procedure for a mainboard with untested board specific code is to first try to probe the ROM (just invoke flashrom and check that it detects your flash chip type) without running the board enable code (i.e. without any parameters). If it finds your chip, fine. Otherwise, retry probing your chip with the board-enable code running, using
flashrom -p internal:boardenable=force
If your chip is still not detected, the board enable code seems to be broken or the flash chip unsupported. Otherwise, make a backup of your current ROM contents (using -r) and store it to a medium outside of your computer, like a USB drive or a network share. If you needed to run the board enable code already for probing, use it for reading too. If reading succeeds and the contens of the read file look legit you can try to write the new image. You should enable the board enable code in any case now, as it has been written because it is known that writing/erasing without the board enable is going to fail. In any case (success or failure), please report to the flashrom mailing list, see below.
On systems running coreboot, flashrom checks whether the desired image matches your mainboard. This needs some special board ID to be present in the image. If flashrom detects that the image you want to write and the current board do not match, it will refuse to write the image unless you specify
flashrom -p internal:boardmismatch=force
If your mainboard is manufactured by GIGABYTE and supports DualBIOS it is very likely that it uses an ITE IT87 series Super I/O to switch between the two flash chips. Only one of them can be accessed at a time and you can manually select which one to use with the
flashrom -p internal:dualbiosindex=chip
syntax where chip is the index of the chip to use (0 = main, 1 = backup). You can check which one is currently selected by leaving out the chip parameter.
If your mainboard uses an ITE IT87 series Super I/O for LPC<->SPI flash bus translation, flashrom should autodetect that configuration. If you want to set the I/O base port of the IT87 series SPI controller manually instead of using the value provided by the BIOS, use the
flashrom -p internal:it87spiport=portnum
syntax where portnum is the I/O port number (must be a multiple of 8). In the unlikely case flashrom doesn't detect an active IT87 LPC<->SPI bridge, please send a bug report so we can diagnose the problem.
Beginning with the SB700 chipset there is an integrated microcontroller (IMC) based on the 8051 embedded in every AMD southbridge. Its firmware resides in the same flash chip as the host's which makes writing to the flash risky if the IMC is active. Flashrom tries to temporarily disable the IMC but even then changing the contents of the flash can have unwanted effects: when the IMC continues (at the latest after a reboot) it will continue executing code from the flash. If the code was removed or changed in an unfortunate way it is unpredictable what the IMC will do. Therefore, if flashrom detects an active IMC it will disable write support unless the user forces it with the
flashrom -p internal:amd_imc_force=yes
syntax. The user is responsible for supplying a suitable image or leaving out the IMC region with the help of a layout file. This limitation might be removed in the future when we understand the details better and have received enough feedback from users. Please report the outcome if you had to use this option to write a chip.
An optional spispeed parameter specifies the frequency of the SPI bus where applicable (i.e. SB600 or later with an SPI flash chip directly attached to the chipset). Syntax is
flashrom -p internal:spispeed=frequency
where frequency can be '16.5 MHz', '22 MHz', '33 MHz', '66 MHz', '100 MHZ', or '800 kHz'. Support of individual frequencies depends on the generation of the chipset:
* SB6xx, SB7xx, SP5xxx: from 16.5 MHz up to and including 33 MHz
* SB8xx, SB9xx, Hudson: from 16.5 MHz up to and including 66 MHz
* Yangtze (with SPI 100 engine as found in Kabini and Tamesh): all of them
The default is to use 16.5 MHz and disable Fast Reads.
If you have an Intel chipset with an ICH8 or later southbridge with SPI flash attached, and if a valid descriptor was written to it (e.g. by the vendor), the chipset provides an alternative way to access the flash chip(s) named Hardware Sequencing. It is much simpler than the normal access method (called Software Sequencing), but does not allow the software to choose the SPI commands to be sent. You can use the
flashrom -p internal:ich_spi_mode=value
syntax where value can be auto, swseq or hwseq. By default (or when setting ich_spi_mode=auto) the module tries to use swseq and only activates hwseq if need be (e.g. if important opcodes are inaccessible due to lockdown; or if more than one flash chip is attached). The other options (swseq, hwseq) select the respective mode (if possible).
ICH8 and later southbridges may also have locked address ranges of different kinds if a valid descriptor was written to it. The flash address space is then partitioned in multiple so called "Flash Regions" containing the host firmware, the ME firmware and so on respectively. The flash descriptor can also specify up to 5 so called "Protected Regions", which are freely chosen address ranges independent from the aforementioned "Flash Regions". All of them can be write and/or read protected individually.
If you have an Intel chipset with an ICH2 or later southbridge and if you want to set specific IDSEL values for a non-default flash chip or an embedded controller (EC), you can use the
flashrom -p internal:fwh_idsel=value
syntax where value is the 48-bit hexadecimal raw value to be written in the IDSEL registers of the Intel southbridge. The upper 32 bits use one hex digit each per 512 kB range between 0xffc00000 and 0xffffffff, and the lower 16 bits use one hex digit each per 1024 kB range between 0xff400000 and 0xff7fffff. The rightmost hex digit corresponds with the lowest address range. All address ranges have a corresponding sister range 4 MB below with identical IDSEL settings. The default value for ICH7 is given in the example below.
Example: flashrom -p internal:fwh_idsel=0x001122334567
Using flashrom on older laptops that don't boot from the SPI bus is dangerous and may easily make your hardware unusable (see also the BUGS section). The embedded controller (EC) in some machines may interact badly with flashing. More information is Problems occur when the flash chip is shared between BIOS and EC firmware, and the latter does not expect flashrom to access the chip. While flashrom tries to change the contents of that memory the EC might need to fetch new instructions or data from it and could stop working correctly. Probing for and reading from the chip may also irritate your EC and cause fan failure, backlight failure, sudden poweroff, and other nasty effects. flashrom will attempt to detect if it is running on such a laptop and limit probing to SPI buses. If you want to probe the LPC bus anyway at your own risk, use
flashrom -p internal:laptop=force_I_want_a_brick
We will not help you if you force flashing on a laptop because this is a really dumb idea.
You have been warned.
Currently we rely on the chassis type encoded in the DMI/SMBIOS data to detect laptops. Some vendors did not implement those bits correctly or set them to generic and/or dummy values. flashrom will then issue a warning and restrict buses like above. In this case you can use
flashrom -p internal:laptop=this_is_not_a_laptop
to tell flashrom (at your own risk) that it is not running on a laptop.
An optional parameter specifies the bus types it should support. For that you have to use the
flashrom -p dummy:bus=[type[+type[+type]]]
syntax where type can be parallel, lpc, fwh, spi in any order. If you specify bus without type, all buses will be disabled. If you do not specify bus, all buses will be enabled.
Example: flashrom -p dummy:bus=lpc+fwh
The dummy programmer supports flash chip emulation for automated self-tests without hardware access. If you want to emulate a flash chip, use the
flashrom -p dummy:emulate=chip
syntax where chip is one of the following chips (please specify only the chip name, not the vendor):
* ST M25P10.RES SPI flash chip (128 kB, RES, page write)
* SST SST25VF040.REMS SPI flash chip (512 kB, REMS, byte write)
* SST SST25VF032B SPI flash chip (4096 kB, RDID, AAI write)
* Macronix MX25L6436 SPI flash chip (8192 kB, RDID, SFDP)
Example: flashrom -p dummy:emulate=SST25VF040.REMS
If you use flash chip emulation, flash image persistence is available as well by using the
flashrom -p dummy:emulate=chip,image=image.rom
syntax where image.rom is the file where the simulated chip contents are read on flashrom startup and where the chip contents on flashrom shutdown are written to.
Example: flashrom -p dummy:emulate=M25P10.RES,image=dummy.bin
If you use SPI flash chip emulation for a chip which supports SPI page write with the default opcode, you can set the maximum allowed write chunk size with the
flashrom -p dummy:emulate=chip,spi_write_256_chunksize=size
syntax where size is the number of bytes (min. 1, max. 256).
Example:
flashrom -p dummy:emulate=M25P10.RES,spi_write_256_chunksize=5
To simulate a programmer which refuses to send certain SPI commands to the flash chip, you can specify a blacklist of SPI commands with the
flashrom -p dummy:spi_blacklist=commandlist
syntax where commandlist is a list of two-digit hexadecimal representations of SPI commands. If commandlist is e.g. 0302, flashrom will behave as if the SPI controller refuses to run command 0x03 (READ) and command 0x02 (WRITE). commandlist may be up to 512 characters (256 commands) long. Implementation note: flashrom will detect an error during command execution.
To simulate a flash chip which ignores (doesn't support) certain SPI commands, you can specify an ignorelist of SPI commands with the
flashrom -p dummy:spi_ignorelist=commandlist
syntax where commandlist is a list of two-digit hexadecimal representations of SPI commands. If commandlist is e.g. 0302, the emulated flash chip will ignore command 0x03 (READ) and command 0x02 (WRITE). commandlist may be up to 512 characters (256 commands) long. Implementation note: flashrom won't detect an error during command execution.
You can specify the initial content of the chip's status register with the
flashrom -p dummy:spi_status=content
syntax where content is an 8-bit hexadecimal value.
flashrom -p xxxx:pci=bb:dd.f,
where xxxx is the name of the programmer, bb is the PCI bus number, dd is the PCI device number, and f is the PCI function number of the desired device.
Example: flashrom -p nic3com:pci=05:04.0
flashrom -p atavia:offset=addr
syntax where addr will be interpreted as usual (leading 0x (0) for hexadecimal (octal) values, or else decimal). For more information please see
An optional parameter specifies the controller type, channel/interface/port and GPIO-based chip select it should support. For that you have to use the
flashrom -p ft2232_spi:type=model,port=interface,csgpiol=gpio
syntax where model can be 2232H, 4232H, 232H, jtagkey, busblaster, openmoko, arm-usb-tiny, arm-usb-tiny-h, arm-usb-ocd, arm-usb-ocd-h, tumpa, tumpalite, picotap, google-servo, google-servo-v2google-servo-v2-legacy interface can be A, B, C, or D and csgpiol can be a number between 0 and 3, denoting GPIOL0-GPIOL3 correspondingly. The default model is 4232H the default interface is A and GPIO is not used by default.
If there is more than one ft2232_spi-compatible device connected, you can select which one should be used by specifying its serial number with the
flashrom -p ft2232_spi:serial=number
syntax where number is the serial number of the device (which can be found for example in the output of lsusb -v).
All models supported by the ft2232_spi driver can configure the SPI clock rate by setting a divisor. The expressible divisors are all even numbers between 2 and 2^17 (=131072) resulting in SPI clock frequencies of 6 MHz down to about 92 Hz for 12 MHz inputs. The default divisor is set to 2, but you can use another one by specifying the optional divisor parameter with the
flashrom -p ft2232_spi:divisor=div
syntax.
A mandatory parameter specifies either a serial device (and baud rate) or an IP/port combination for communicating with the programmer. The device/baud combination has to start with dev= and separate the optional baud rate with a colon. For example
flashrom -p serprog:dev=/dev/ttyS0:115200
If no baud rate is given the default values by the operating system/hardware will be used. For IP connections you have to use the
flashrom -p serprog:ip=ipaddr:port
syntax. In case the device supports it, you can set the SPI clock frequency with the optional spispeed parameter. The frequency is parsed as hertz, unless an M, or k suffix is given, then megahertz or kilohertz are used respectively. Example that sets the frequency to 2 MHz:
flashrom -p serprog:dev=/dev/device:baud,spispeed=2M
More information about serprog is available in serprog-protocol.txt in the source distribution.
flashrom -p buspirate_spi:dev=/dev/device,spispeed=frequency
where frequency can be 30k, 125k, 250k, 1M, 2M, 2.6M, 4M or 8M (in Hz). The default is the maximum frequency of 8 MHz.
The baud rate for communication between the host and the Bus Pirate can be specified with the optional serialspeed parameter. Syntax is
flashrom -p buspirate_spi:serialspeed=baud
where baud can be 115200, 230400, 250000 or 2000000 (2M). The default is 2M baud for Bus Pirate hardware version 3.0 and greater, and 115200 otherwise.
An optional pullups parameter specifies the use of the Bus Pirate internal pull-up resistors. This may be needed if you are working with a flash ROM chip that you have physically removed from the board. Syntax is
flashrom -p buspirate_spi:pullups=state
where state can be on or off. More information about the Bus Pirate pull-up resistors and their purpose is available Only the external supply voltage (Vpu) is supported as of this writing.
flashrom -p pickit2_spi:voltage=value
where value can be 0V, 1.8V, 2.5V, 3.5V or the equivalent in mV.
An optional spispeed parameter specifies the frequency of the SPI bus. Syntax is
flashrom -p pickit2_spi:spispeed=frequency
where frequency can be 250k, 333k, 500k or 1M (in Hz). The default is a frequency of 1 MHz.
flashrom -p dediprog:voltage=value
where value can be 0V, 1.8V, 2.5V, 3.5V or the equivalent in mV.
An optional device parameter specifies which of multiple connected Dediprog devices should be used. Please be aware that the order depends on libusb's usb_get_busses() function and that the numbering starts at 0. Usage example to select the second device:
flashrom -p dediprog:device=1
An optional spispeed parameter specifies the frequency of the SPI bus. The firmware on the device needs to be 5.0.0 or newer. Syntax is
flashrom -p dediprog:spispeed=frequency
where frequency can be 375k, 750k, 1.5M, 2.18M, 3M, 8M, 12M or 24M (in Hz). The default is a frequency of 12 MHz.
An optional target parameter specifies which target chip should be used. Syntax is
flashrom -p dediprog:target=value
where value can be 1 or 2 to select target chip 1 or 2 respectively. The default is target chip 1.
flashrom -p rayer_spi:iobase=baseaddr
syntax where baseaddr is base I/O port address of the parallel port, which must be a multiple of four. Make sure to not forget the "0x" prefix for hexadecimal port addresses.
The default cable type is the RayeR cable. You can use the optional type parameter to specify the cable type with the
flashrom -p rayer_spi:type=model
syntax where model can be rayer for the RayeR cable, byteblastermv for the Altera ByteBlasterMV, stk200 for the Atmel STK200/300, wiggler for the Macraigor Wiggler, xilinx for the Xilinx Parallel Cable III (DLC 5), or spi_tt for SPI Tiny Tools-compatible hardware.
More information about the RayeR hardware is available at The Altera ByteBlasterMV datasheet can be obtained from For more information about the Macraigor Wiggler see The schematic of the Xilinx DLC 5 was published in
Information about the SI-Prog adapter can be found at
An example call to flashrom is
flashrom -p pony_spi:dev=/dev/ttyS0,type=serbang
Please note that while USB-to-serial adapters work under certain circumstances, this slows down operation considerably.
flashrom -p ogp_spi:rom=name
Where name is either cprom or s3 for the configuration ROM and bprom or bios for the BIOS ROM. If more than one card supported by the ogp_spi programmer is installed in your system, you have to specify the PCI address of the card you want to use with the pci= parameter as explained in the nic3com et al. section above.
flashrom -p linux_mtd:dev=/dev/mtdX
syntax where /dev/mtdX is the Linux device node for your MTD device. If left unspecified the first MTD device found (e.g. /dev/mtd0) will be used by default.
Please note that the linux_mtd driver only works on Linux.
flashrom -p linux_spi:dev=/dev/spidevX.Y
syntax where /dev/spidevX.Y is the Linux device node for your SPI controller.
In case the device supports it, you can set the SPI clock frequency with the optional spispeed parameter. The frequency is parsed as kilohertz. Example that sets the frequency to 8 MHz:
flashrom -p linux_spi:dev=/dev/spidevX.Y,spispeed=8000
Please note that the linux_spi driver only works on Linux.
IMPORTANT: Before using this programmer, the display MUST be in standby mode, and only connected to the computer that will run flashrom using a VGA cable, to an inactive VGA output. It absolutely MUST NOT be used as a display during the procedure!
You have to specify the DDC/I2C controller and I2C address to use with the
flashrom -p mstarddc_spi:dev=/dev/i2c-X:YY
syntax where /dev/i2c-X is the Linux device node for your I2C controller connected to the display's DDC channel, and YY is the (hexadecimal) address of the MSTAR ISP port (address 0x49 is usually used). Example that uses I2C controller /dev/i2c-1 and address 0x49:
flashrom -p mstarddc_spi:dev=/dev/i2c-1:49
It is also possible to inhibit the reset command that is normally sent to the display once the flashrom operation is completed using the optional noreset parameter. A value of 1 prevents flashrom from sending the reset command. Example that does not reset the display at the end of the operation:
flashrom -p mstarddc_spi:dev=/dev/i2c-1:49,noreset=1
Please note that sending the reset command is also inhibited if an error occurred during the operation. To send the reset command afterwards, you can simply run flashrom once more, in chip probe mode (not specifying an operation), without the noreset parameter, once the flash read/write operation you intended to perform has completed successfully.
Please also note that the mstarddc_spi driver only works on Linux.
flashrom -p ni845x_spi:voltage=value
where value can be 1.2V, 1.5V, 1.8V, 2.5V, 3.3V or the equivalent in mV.
In the case if none of the programmer's supported IO voltage is within the supported voltage range of the detected flash chip the flashrom will abort the operation (to prevent damaging the flash chip). You can override this behaviour by passing "yes" to the ignore_io_voltage_limits parameter (for e.g. if you are using an external voltage translator circuit). Syntax is
flashrom -p ni845x_spi:ignore_io_voltage_limits=yes
You can use the serial parameter to explicitly specify which connected NI USB-845x device should be used. You should use your device's 7 digit hexadecimal serial number. Usage example to select the device with 1230A12 serial number:
flashrom -p ni845x_spi:serial=1230A12
An optional spispeed parameter specifies the frequency of the SPI bus. Syntax is
flashrom -p ni845x_spi:spispeed=frequency
where frequency should a number corresponding to the desired frequency in kHz. The maximum frequency is 12 MHz (12000 kHz) for the USB-8451 and 50 MHz (50000 kHz) for the USB-8452. The default is a frequency of 1 MHz (1000 kHz).
An optional cs parameter specifies which target chip select line should be used. Syntax is
flashrom -p ni845x_spi:csnumber=value
where value should be between 0 and 7 By default the CS0 is used.
flashrom -p digilent_spi:spispeed=frequency
where frequency can be 62.5k, 125k, 250k, 500k, 1M, 2M or 4M (in Hz). The default is a frequency of 4 MHz.
The MOSI signal of the flash chip must be attached to TDI pin of the programmer, MISO to TDO and SCK to TCK. The chip select (CS) signal of the flash chip can be attached to different pins of the programmer which can be selected with the
flashrom -p jlink_spi:cs=pin
syntax where pin can be either TRST or RESET.
The default pin for chip select is RESET.
Note that, when using RESET, it is normal that the indicator LED blinks
orange or red.
Additionally, the VTref pin of the programmer must be attached to the
logic level of the flash chip.
The programmer measures the voltage on this pin and generates the reference
voltage for its input comparators and adapts its output voltages to it.
Pinout for devices with 20-pin JTAG connector:
+-------+
| 1 2 | 1: VTref 2:
| 3 4 | 3: TRST 4: GND
| 5 6 | 5: TDI 6: GND
+-+ 7 8 | 7: 8: GND
| 9 10 | 9: TCK 10: GND
| 11 12 | 11: 12: GND
+-+ 13 14 | 13: TDO 14:
| 15 16 | 15: RESET 16:
| 17 18 | 17: 18:
| 19 20 | 19: PWR_5V 20:
+-------+
If there is more than one compatible device connected, you can select which one should be used by specifying its serial number with the
flashrom -p jlink_spi:serial=number
syntax where number is the serial number of the device (which can be found for example in the output of lsusb -v).
The SPI speed can be selected by using the
flashrom -p jlink_spi:spispeed=frequency
syntax where frequency is the SPI clock frequency in kHz. The maximum speed depends on the device in use.
flashrom -p stlinkv3_spi
If there is more than one compatible device connected, you can select which one should be used by specifying its serial number with the
flashrom -p stlinkv3_spi:serial=number
syntax where number is the serial number of the device (which can be found for example in the output of lsusb -v).
The SPI speed can be selected by using the
flashrom -p stlinkv3_spi:spispeed=frequency
syntax where frequency is the SPI clock frequency in kHz. If the passed frequency is not supported by the adapter the nearest lower supported frequency will be used.
flashrom -p internal -r backup.rom -o backuplog.txt
flashrom -p internal -w newbios.rom -o writelog.txt
Please make sure to copy backup.rom to some external media before you try
to write. That makes offline recovery easier.
If writing fails and flashrom complains about the chip being in an unknown
state, you can try to restore the backup by running
flashrom -p internal -w backup.rom -o restorelog.txt
If you encounter any problems, please contact us and supply backuplog.txt, writelog.txt and restorelog.txt. See section BUGS for contact info.
internal needs raw memory access, PCI configuration space access, raw I/O port access (x86) and MSR access (x86).
atavia needs PCI configuration space access.
nic3com, nicrealtek and nicnatsemi need PCI configuration space read access and raw I/O port access.
atahpt needs PCI configuration space access and raw I/O port access.
gfxnvidia, drkaiser and it8212 need PCI configuration space access and raw memory access.
rayer_spi needs raw I/O port access.
satasii, nicintel, nicintel_eeprom and nicintel_spi need PCI configuration space read access and raw memory access.
satamv and atapromise need PCI configuration space read access, raw I/O port access and raw memory access.
serprog needs TCP access to the network or userspace access to a serial port.
buspirate_spi needs userspace access to a serial port.
ft2232_spi, usbblaster_spi and pickit2_spi need access to the respective USB device via libusb API version 0.1.
ch341a_spi and dediprog need access to the respective USB device via libusb API version 1.0.
dummy needs no access permissions at all.
internal, nic3com, nicrealtek, nicnatsemi, gfxnvidia, drkaiser, satasii, satamv, atahpt, atavia and atapromise have to be run as superuser/root, and need additional raw access permission.
serprog, buspirate_spi, dediprog, usbblaster_spi, ft2232_spi, pickit2_spi, ch341a_spi and digilent_spi can be run as normal user on most operating systems if appropriate device permissions are set.
ogp needs PCI configuration space read access and raw memory access.
On OpenBSD, you can obtain raw access permission by setting securelevel=-1 in /etc/rc.securelevel and rebooting, or rebooting into single user mode.
We recommend to subscribe first at
Many of the developers communicate via the #flashrom IRC channel on chat.freenode.net. If you don't have an IRC client, you can use the You are welcome to join and ask questions, send us bug and success reports there too. Please provide a way to contact you later (e.g. a mail address) and be patient if there is no immediate reaction. Also, we provide a that is very useful when you want to share logs etc. without spamming the channel.
Using flashrom on older laptops is dangerous and may easily make your hardware unusable. flashrom will attempt to detect if it is running on a susceptible laptop and restrict flash-chip probing for safety reasons. Please see the detailed discussion of this topic and associated flashrom options in the Laptops paragraph in the internal programmer subsection of the PROGRAMMER-SPECIFIC INFORMATION section and the information
Some flash chips contain OTP memory often denoted as "security registers". They usually have a capacity in the range of some bytes to a few hundred bytes and can be used to give devices unique IDs etc. flashrom is not able to read or write these memories and may therefore not be able to duplicate a chip completely. For chip types known to include OTP memories a warning is printed when they are detected.
Similar to OTP memories are unique, factory programmed, unforgeable IDs. They are not modifiable by the user at all.
This manual page was written by Uwe Hermann <uwe@hermann-uwe.de>, Carl-Daniel Hailfinger, Stefan Tauner and others. It is licensed under the terms of the GNU GPL (version 2 or later).