b5401a6266
Commit 35599f9a66 (Docs: Replace Recommonmark with MyST Parser)
converted recommonmark style toctrees in bulk using a script. This was
done by searching for lists of references, which is how recommonmark
denoted toctree entries. However, this also converted lists of external
URLs, which would not normally be included in the toctree. Revert these
cases back to lists of URLs as they were before the migration.
Change-Id: Ie4da3d908d4b84c2c7e3572fb4baaeed1f8edb45
Signed-off-by: Nicholas Chin <nic.c3.14@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/84244
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Felix Singer <service+coreboot-gerrit@felixsinger.de>
3.2 KiB
3.2 KiB
Intel Firmware Interface Table
The FIT allows to run code before the actual IA32 reset vector is executed
by the CPU. The FIT resides in the BIOS region (usually near the reset vector)
and is pointed to by the FIT pointer residing at 0xFFFFFFC0.
Table layout
The table consists of blocks each 16 bytes in size. The first is called FIT header the other are called FIT entry.
Fit types
Each entry has a type that give the other bits in the entry a different meaning. The following types are known:
+-----------+------------------------------------------------------------------+
| no. | Description |
+===========+==================================================================+
| 0x0 | HEADER. |
+-----------+------------------------------------------------------------------+
| 0x1 | MICROCODE. |
+-----------+------------------------------------------------------------------+
| 0x2 | STARTUP_ACM. |
+-----------+------------------------------------------------------------------+
| 0x7 | BIOS_STARTUP_MODULE. |
+-----------+------------------------------------------------------------------+
| 0x8 | TPM_POLICY. |
+-----------+------------------------------------------------------------------+
| 0x9 | BIOS_POLICY. |
+-----------+------------------------------------------------------------------+
| 0xa | TXT_POLICY. |
+-----------+------------------------------------------------------------------+
| 0xb | KEY_MANIFEST. |
+-----------+------------------------------------------------------------------+
| 0xc | BOOT_POLICY_MANIFEST. |
+-----------+------------------------------------------------------------------+
| 0x10 | CSE_SECURE_BOOT. |
+-----------+------------------------------------------------------------------+
| 0x2d | TXTSX_POLICY. |
+-----------+------------------------------------------------------------------+
| 0x2f | JMP_DEBUG_POLICY. |
+-----------+------------------------------------------------------------------+
| 0x7f | SKIP. |
+-----------+------------------------------------------------------------------+
Usage in coreboot
The most common usage of FIT is to use Type1 to update microcode before execution of the IA32 reset vector happens.