changeset 426:1060bf70d95d

doc/Compal-unlock: added cautionary note about flashing firmwares containing boot code that checks the word at 0x2060
author Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
date Sat, 21 Jun 2014 06:55:27 +0000
parents f81a931f9172
children 7e305184b0b4
files doc/Compal-unlock
diffstat 1 files changed, 10 insertions(+), 1 deletions(-) [+]
line wrap: on
line diff
--- a/doc/Compal-unlock	Thu Jun 19 20:17:28 2014 +0000
+++ b/doc/Compal-unlock	Sat Jun 21 06:55:27 2014 +0000
@@ -34,7 +34,7 @@
 
 However, Mot/Compal's standard firmware on these phones includes a bootloader,
 a part that executes before any of the rest of the fw image is allowed to
-execute or made use of in any way, and this Compal-specific bootloader has a
+execute or is made use of in any way, and this Compal-specific bootloader has a
 provision for interrupting the boot process and diverting it to an externally-
 supplied piece of code loaded over the serial line.  Older fw versions have
 this feature enabled unconditionally, but some of the newer versions have a
@@ -265,6 +265,15 @@
 erase and program operations appropriately for the flash configuration in your
 phone.
 
+One last word of caution: if you are going to flash some fw version other than
+the unlocked North American C139 one discussed above, please check to see what
+boot code version it includes, and whether or not that version has the
+malfeature of checking the flash word at 0x2060 for the serial access control
+flag.  If the fw version you are seeking to play with has boot code with that
+malfeature present, the bricking vulnerability window extends until you not
+only program the new boot code into flash, but also program 0xDDDDDDDD into
+that 0x2060 word.  You've been warned.
+
 C155/156 differences
 ====================