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| author | Francis Rowe <info@gluglug.org.uk> | 2015-05-07 12:13:44 (EDT) |
|---|---|---|
| committer | Francis Rowe <info@gluglug.org.uk> | 2015-05-07 12:15:24 (EDT) |
| commit | 969ac353569c8f9f29a7a97e4d24203b04d7d8c2 (patch) | |
| tree | cb069f52bf264023e8d2ab2d2958f7eabe3acbbb | |
| parent | 97d04f9ebf40c1691dad369fb6d70c84068694c0 (diff) | |
| download | libreboot-969ac353569c8f9f29a7a97e4d24203b04d7d8c2.zip libreboot-969ac353569c8f9f29a7a97e4d24203b04d7d8c2.tar.gz libreboot-969ac353569c8f9f29a7a97e4d24203b04d7d8c2.tar.bz2 | |
docs/hcl/gm45_remove_me.html: notes about the demefactory util
| -rw-r--r-- | docs/hcl/gm45_remove_me.html | 55 | ||||
| -rw-r--r-- | docs/tasks.html | 11 |
2 files changed, 66 insertions, 0 deletions
diff --git a/docs/hcl/gm45_remove_me.html b/docs/hcl/gm45_remove_me.html index 8f7d56f..0e86166 100644 --- a/docs/hcl/gm45_remove_me.html +++ b/docs/hcl/gm45_remove_me.html @@ -228,6 +228,61 @@ </p> </div> + + <div class="section"> + + <h1 id="demefactory">demefactory utility</h1> + + <p> + This takes a factory.rom dump and disables the ME/TPM, but leaves the region intact. + It also sets all regions read-write. + </p> + + <p> + The ME interferes with flash read/write in flashrom, and the default descriptor + locks some regions. The idea is that doing this will remove all of those restrictions. + </p> + + <p> + Simply run (with factory.rom in the same directory):<br/> + $ <b>./demefactory</b> + </p> + + <p> + It will generate a 4KiB descriptor file (only the descriptor, no GbE). Insert that into + a factory.rom image (NOTE: do this on a copy of it. Keep the original factory.rom stored + safely somewhere):<br/> + $ <b>dd if=demefactory_4kdescriptor.bin of=factory_nome.rom bs=1 count=4k conv=notrunc</b> + </p> + + <p> + TODO: test this.<br/> + TODO: lenovobios (GM45 thinkpads) still write-protects parts of the flash. Modify the assembly code + inside. + Note: the factory.rom (BIOS region) from lenovobios is in a compressed format, which you have to extract. + bios_extract upstream won't work, but the following was said in #coreboot on freenode IRC: + </p> +<pre> +<roxfan> fchmmr: try bios_extract with ffv patch <a href="http://patchwork.coreboot.org/patch/3444/">http://patchwork.coreboot.org/patch/3444/</a> +<roxfan> or <a href="https://github.com/coreboot/bios_extract/blob/master/phoenix_extract.py">https://github.com/coreboot/bios_extract/blob/master/phoenix_extract.py</a> +<roxfan> what are you looking for specifically, btw? + +0x74: 0x9fff03e0 PR0: Warning: 0x003e0000-0x01ffffff is read-only. +0x84: 0x81ff81f8 PR4: Warning: 0x001f8000-0x001fffff is locked. +</pre> + + <p> + Use-case: a factory.rom image modified in this way would theoretically have no + flash protections whatsoever, making it easy to quickly switch between factory/libreboot + in software, without ever having to disassemble and re-flash externally unless you brick + the device. + </p> + + <p> + demefactory is part of the ich9deblob src, found at <i>resources/utilities/ich9deblob/</i> + </p> + + </div> <div class="section"> diff --git a/docs/tasks.html b/docs/tasks.html index b188aaa..2cf4852 100644 --- a/docs/tasks.html +++ b/docs/tasks.html @@ -275,6 +275,17 @@ </li> </ul> + <h3> + Flashing from lenovobios to libreboot (and vice versa) + </h3> + <ul> + <li> + Implement everything outlined in + <a href="hcl/gm45_remove_me.html#demefactory">hcl/gm45_remove_me.html#demefactory</a> + and test it. + </li> + </ul> + <h3>Payloads</h3> <ul> <li> |