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Diffstat (limited to 'README.fmap')
| -rw-r--r-- | README.fmap | 40 |
1 files changed, 0 insertions, 40 deletions
diff --git a/README.fmap b/README.fmap deleted file mode 100644 index 416d27fe50..0000000000 --- a/README.fmap +++ /dev/null @@ -1,40 +0,0 @@ -In the most general case, the flash layout looks something like this: - - +---------------------+ - | Reserved for EC use | - +---------------------+ - - +---------------------+ - | Vblock B | - +---------------------+ - | RW firmware B | - +---------------------+ - - +---------------------+ - | Vblock A | - +---------------------+ - | RW firmware A | - +---------------------+ - - +---------------------+ - | FMAP | - +---------------------+ - | Public root key | - +---------------------+ - | Read-only firmware | - +---------------------+ - - -BIOS firmware (and kernel) put the vblock info at the start of each image -where it's easy to find. The Blizzard EC expects the firmware vector table -to come first, so we have to put the vblock at the end. This means we have -to know where to look for it, but that's built into the FMAP and the RO -firmware anyway, so that's not an issue. - -The RO firmware doesn't need a vblock of course, but it does need some -reserved space for vboot-related things. - -Using SHA256/RSA4096, the vblock is 2468 bytes (0x9a4), while the public -root key is 1064 bytes (0x428) and the current FMAP is 644 bytes (0x284). If -we reserve 4K at the top of each FW image, that should give us plenty of -room for vboot-related stuff. |