enable_flash_ich: warn if SMM BIOS Write Protection is detected in BIOS_CNTL
Corresponding to flashrom svn r1332.
Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
Acked-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
diff --git a/chipset_enable.c b/chipset_enable.c
index b5385dc..afb82aa 100644
--- a/chipset_enable.c
+++ b/chipset_enable.c
@@ -264,8 +264,17 @@
(old & (1 << 0)) ? "en" : "dis");
msg_pdbg("BIOS_CNTL is 0x%x\n", old);
- new = old | 1;
+ /*
+ * Quote from the 6 Series datasheet (Document Number: 324645-004):
+ * "Bit 5: SMM BIOS Write Protect Disable (SMM_BWP)
+ * 1 = BIOS region SMM protection is enabled.
+ * The BIOS Region is not writable unless all processors are in SMM."
+ * In earlier chipsets this bit is reserved. */
+ if (old & (1 << 5)) {
+ msg_pinfo("WARNING: BIOS region SMM protection is enabled!\n");
+ }
+ new = old | 1;
if (new == old)
return 0;