Difference between revisions of "GM45 Thinkpad Internal flashing research"

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  GbE                  rw     
 
  GbE                  rw     
  
The issue is that the BIOS reagion is still partially locked:
+
The issue is that the BIOS region is still partially locked:
 
  0x74: 0x9fff07e0 PR0: Warning: 0x007e0000-0x01ffffff is read-only.
 
  0x74: 0x9fff07e0 PR0: Warning: 0x007e0000-0x01ffffff is read-only.
  
 
The flash descriptor probably cannot be reflashed easily from the x86 CPU, however messing with the ME partition is probably doable if we get luck with the BIOS:
 
The flash descriptor probably cannot be reflashed easily from the x86 CPU, however messing with the ME partition is probably doable if we get luck with the BIOS:
 
If we remove the RAM DIMM from slot0, the BIOS outputs an error message on the screen that asks to put the DIMM back and refuses to boot. I guess it's related to what mysteries_intel.txt (inside flashrom source ) was mentioning.
 
If we remove the RAM DIMM from slot0, the BIOS outputs an error message on the screen that asks to put the DIMM back and refuses to boot. I guess it's related to what mysteries_intel.txt (inside flashrom source ) was mentioning.
 +
 +
So I guess that either:
 +
* The BIOS can only be partially flashed at all.
 +
* The BIOS can be flashed by the vendor tools which probably reboots the computer when doing it. In that case the code doing the PR0 Locking could be located after the PR0 locked reagion.

Revision as of 23:03, 17 January 2015

Here is a log of flashrom on the flash chip of an X200T In the log, we can see that the BIOS region is set read-write in the flash descriptor:

      Descr. BIOS ME GbE Platf.
BIOS    r     rw      rw   rw
ME      r         rw  rw     
GbE                   rw     

The issue is that the BIOS region is still partially locked:

0x74: 0x9fff07e0 PR0: Warning: 0x007e0000-0x01ffffff is read-only.

The flash descriptor probably cannot be reflashed easily from the x86 CPU, however messing with the ME partition is probably doable if we get luck with the BIOS: If we remove the RAM DIMM from slot0, the BIOS outputs an error message on the screen that asks to put the DIMM back and refuses to boot. I guess it's related to what mysteries_intel.txt (inside flashrom source ) was mentioning.

So I guess that either:

  • The BIOS can only be partially flashed at all.
  • The BIOS can be flashed by the vendor tools which probably reboots the computer when doing it. In that case the code doing the PR0 Locking could be located after the PR0 locked reagion.