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Documentation: Add basic flashing tutorial for Lenovo * Add basic flashing tutorial ** Describe internal and external flashing ** Describe flash supply diode protection ** Gives general advices on flashing ** Describe how to use flashrom --ifd * Describe basic flashing on Lenovo T4xx devices ** Describe how to disassemble and access the flash IC on T4xx ** Describe flash layout on Sandy Bridge and Ivy Bridge series. Change-Id: Ia833e27f4e7d89ee32be9bed21a0c021839facec Signed-off-by: Patrick Rudolph <siro@das-labor.org> Reviewed-on: https://review.coreboot.org/27852 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
2018-08-04 10:04:45 +02:00
# Flashing firmware tutorial
Updating the firmware is possible using the **internal method**, where the updates
happen from a running system, or using the **external method**, where the system
is in a shut down state and an external programmer is attached to write into the
flash IC.
## Contents
* [Flashing internaly](int_flashrom.md)
* [Flashing firmware standalone](ext_standalone.md)
* [Flashing firmware externally supplying direct power](ext_power.md)
* [Flashing firmware externally without supplying direct power](no_ext_power.md)
## General advice
* It's recommended to only flash the BIOS region.
* Always verify the firmware image.
* If you flash externally and have transmission errors:
* Use short wires
* Reduce clock frequency
* Check power supply
* Make sure that there are no other bus masters (EC, ME, SoC, ...)
## Internal method
This method using [flashrom] is available on many platforms, as long as they
aren't locked down.
There are various protection schemes that make it impossible to modify or
replace a firmware from a running system. coreboot allows to disable these
mechanisms, making it possible to overwrite (or update) the firmware from a
running system.
Usually you must use the **external method** once to install a retrofitted
coreboot and then you can use the **internal method** for future updates.
There are multiple ways to update the firmware:
* Using flashrom's *internal* programmer to directly write into the firmware
flash IC, running on the target machine itself
* A proprietary software to update the firmware, running on the target machine
itself
* A UEFI firmware update capsule
More details on flashrom's
* [internal programmer](int_flashrom.md)
## External method
External flashing is possible on many platforms, but requires disassembling
the target hardware. You need to buy a flash programmer, that
exposes the same interface as your flash IC (likely SPI).
Please also have a look at the mainboard-specific documentation for details.
After exposing the firmware flash IC, read the schematics and use one of the
possible methods:
* [Flashing firmware standalone](ext_standalone.md)
* [Flashing firmware externally supplying direct power](ext_power.md)
* [Flashing firmware externally without supplying direct power](no_ext_power.md)
**WARNING:** Using the wrong method or accidentally using the wrong pinout might
permanently damage your hardware!
Documentation/flash_tutorial/index.md: warn about dots painted on ICs I fried my mainboard because I tried to orient my chip by lining a blue dot on the corner of my chip with a dot depicted on the chip datasheet. They apparently have nothing to do with each other, and this is normal. Add warning about this to the docs to hopefully spare others from a similar fate. Signed-off-by: Michael Bacarella <michael.bacarella@gmail.com> Change-Id: Ib634589aaa11f75bde2ef2e13d2cacc4cae19a3f Signed-off-by: Michael Bacarella <michael.bacarella@gmail.com> Reviewed-on: https://review.coreboot.org/c/30028 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
2018-12-03 22:43:53 +01:00
**WARNING:** Do not rely on dots *painted* on flash ICs to orient the pins!
Any dots painted on flash ICs may only indicate if they've been tested. Dots
that appear in datasheets to indicate pin 1 correspond to some kind of physical
marker, such as a drilled hole, or one side being more flat than the other.
Documentation: Add basic flashing tutorial for Lenovo * Add basic flashing tutorial ** Describe internal and external flashing ** Describe flash supply diode protection ** Gives general advices on flashing ** Describe how to use flashrom --ifd * Describe basic flashing on Lenovo T4xx devices ** Describe how to disassemble and access the flash IC on T4xx ** Describe flash layout on Sandy Bridge and Ivy Bridge series. Change-Id: Ia833e27f4e7d89ee32be9bed21a0c021839facec Signed-off-by: Patrick Rudolph <siro@das-labor.org> Reviewed-on: https://review.coreboot.org/27852 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
2018-08-04 10:04:45 +02:00
## Using a layout file
On platforms where the flash IC is shared with other components you might want
to write only a part of the flash IC. On Intel for example there are IFD, ME and
GBE which don't need to be updated to install coreboot.
To make [flashrom] only write the *bios* region, leaving Intel ME and Intel IFD
Documentation: Clarify minor detail on preparing a layout file The user needs to pass the original firmware image to create a layout file, not the newly compiled coreboot image. Signed-off-by: Michael Bacarella <michael.bacarella@gmail.com> Change-Id: If47a88f06076da12d8da7a873c3e5ef64fc1f877 Reviewed-on: https://review.coreboot.org/c/30024 Reviewed-by: Angel Pons <th3fanbus@gmail.com> Reviewed-by: Patrick Georgi <pgeorgi@google.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2018-12-03 20:23:43 +01:00
untouched, you can use a layout file, which can be created with ifdtool and a backup
of the original firmware.
Documentation: Add basic flashing tutorial for Lenovo * Add basic flashing tutorial ** Describe internal and external flashing ** Describe flash supply diode protection ** Gives general advices on flashing ** Describe how to use flashrom --ifd * Describe basic flashing on Lenovo T4xx devices ** Describe how to disassemble and access the flash IC on T4xx ** Describe flash layout on Sandy Bridge and Ivy Bridge series. Change-Id: Ia833e27f4e7d89ee32be9bed21a0c021839facec Signed-off-by: Patrick Rudolph <siro@das-labor.org> Reviewed-on: https://review.coreboot.org/27852 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
2018-08-04 10:04:45 +02:00
```bash
Documentation: Clarify minor detail on preparing a layout file The user needs to pass the original firmware image to create a layout file, not the newly compiled coreboot image. Signed-off-by: Michael Bacarella <michael.bacarella@gmail.com> Change-Id: If47a88f06076da12d8da7a873c3e5ef64fc1f877 Reviewed-on: https://review.coreboot.org/c/30024 Reviewed-by: Angel Pons <th3fanbus@gmail.com> Reviewed-by: Patrick Georgi <pgeorgi@google.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2018-12-03 20:23:43 +01:00
ifdtool -f rom.layout backup.rom
Documentation: Add basic flashing tutorial for Lenovo * Add basic flashing tutorial ** Describe internal and external flashing ** Describe flash supply diode protection ** Gives general advices on flashing ** Describe how to use flashrom --ifd * Describe basic flashing on Lenovo T4xx devices ** Describe how to disassemble and access the flash IC on T4xx ** Describe flash layout on Sandy Bridge and Ivy Bridge series. Change-Id: Ia833e27f4e7d89ee32be9bed21a0c021839facec Signed-off-by: Patrick Rudolph <siro@das-labor.org> Reviewed-on: https://review.coreboot.org/27852 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
2018-08-04 10:04:45 +02:00
```
and looks similar to:
```
00000000:00000fff fd
00500000:00bfffff bios
00003000:004fffff me
00001000:00002fff gbe
```
By specifying *-l* and *-i* [flashrom] writes a single region:
```bash
flashrom -l rom.layout -i bios -w coreboot.rom -p <programmer>
```
## Using an IFD to determine the layout
flashrom version 1.0 supports reading the layout from the IFD (first 4KiB of
the ROM). You don't need to manually specify a layout it, but it only works
under the following conditions:
* Only available on Intel ICH7+
* There's only one flash IC when flashing externally
```bash
flashrom --ifd -i bios -w coreboot.rom -p <programmer>
```
**TODO** explain FMAP regions, normal/fallback mechanism, flash lock mechanisms
[flashrom]: https://www.flashrom.org/Flashrom