From 15d840558480536ddaca71bc1876254d59fca7fe Mon Sep 17 00:00:00 2001 From: Patrick Rudolph Date: Sat, 4 Aug 2018 10:04:45 +0200 Subject: 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 Reviewed-on: https://review.coreboot.org/27852 Tested-by: build bot (Jenkins) Reviewed-by: Philipp Deppenwiese --- Documentation/flash_tutorial/ext_standalone.md | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 Documentation/flash_tutorial/ext_standalone.md (limited to 'Documentation/flash_tutorial/ext_standalone.md') diff --git a/Documentation/flash_tutorial/ext_standalone.md b/Documentation/flash_tutorial/ext_standalone.md new file mode 100644 index 0000000000..3a676ce47c --- /dev/null +++ b/Documentation/flash_tutorial/ext_standalone.md @@ -0,0 +1,23 @@ +# Flashing firmware standalone + +If none of the other methods work, there are three possibilities: + +## Desolder +You must remove or desolder the flash IC before you can flash it. +It's recommended to solder a socket in place of the flash IC. + +When flashing the IC, always connect all input pins. +If in doubt, pull /WP, /HOLD, /RESET and alike up towards Vcc. + +## SPI flash emulator +If you are a developer, you might want to use an [EM100Pro] instead, which sets +the onboard flash on hold, and allows to run custom firmware. +It provides a very fast development cycle without actually writing to flash. + +## SPI flash overwrite +It is possible to set the onboard flash on hold and use another flash chip. +Connect all lines one-to-one, except /HOLD. Pull /HOLD of the soldered flash IC +low, and /HOLD of your replacement flash IC high. + + +[EM100Pro]: https://www.dediprog.com/product/EM100Pro -- cgit v1.2.3