Diffstat (limited to 'Documentation/mysteries_intel.txt')
1 files changed, 16 insertions, 3 deletions
diff --git a/Documentation/mysteries_intel.txt b/Documentation/mysteries_intel.txt
index 55921cf..10cb37d 100644
@@ -14,10 +14,18 @@
when trying to touch an address outside of any region.
See also http://www.flashrom.org/pipermail/flashrom/2011-August/007606.html
-= Unlocking the ME region =
+= (Un)locking the ME region =
If the ME region is locked by the FRAP register in descriptor mode, the host
- software is not allowed to read or write any address inside that region. There
- are different ways to unlock access:
+ software is not allowed to read or write any address inside that region.
+ Although the chipset datasheets specify that "[t]he contents of this register
+ are that of the Flash Descriptor" [PANTHER], this is not entirely true.
+ The firmware has to fill at least some of the registers involved. It is not
+ known when they become read-only or any other details, but there is at least
+ one HM67-based board, that provides an user-changeable setting in the firmware
+ user interface to enable ME region updates that lead to a FRAP content that is
+ not equal to the descriptor region bits [NC9B].
+ There are different ways to unlock access:
- A pin strap: Flash Descriptor Security Override Strap (as indicated by the
Flash Descriptor Override Pin Strap Status (FDOPSS) in HSFS. That pin is
@@ -81,6 +89,11 @@
vendor tools use it for updates. This needs to be investigated further before
drawing any conclusion.
+[PANTHER] Intel 7 Series Chipset Family Platform Controller Hub (PCH) Datasheet
+ Document Number: 326776, April 2012, page 857
+[NC9B] Jetway NC9B flashrom v0.9.5.2-r1517 log with ME region unlocked.
+ NB: "FRAP 0e0f" vs. "FLMSTR1 0a0b".
[MODE_CTRL] Client Platform Enabling Tour: Platform Software
Document Number: 439167, Revision 1.2, page 52
[MEBX] Intel Management Engine BIOS Extension (MEBX) User's Guide