Nvidia MCP 78S User Manual page 53

D6
D7
D8
D9
DA
DC
E1-E8
EC-EE
Bootblock Recovery Code Checkpoints
The Bootblock recovery code gets control when the BIOS determines that a BIOS
recovery needs to occur because the user has forced the update or the BIOS
checksum is corrupt. The following table describes the type of checkpoints that may
occur during the Bootblock recovery portion of the BIOS:
Checkpoint
E0
E9
EA
EB
EF
F0
F1
F2
code to memory in right segments. Copies BIOS from ROM to RAM for faster
access. Performs main BIOS checksum and updates recovery status
accordingly.
Both key sequence and OEM specific method is checked to determine if BIOS
recovery is forced. If BIOS recovery is necessary, control flows to
checkpoint E0. See Bootblock Recovery Code Checkpoints section of
document for more information.
Restore CPUID value back into register. The Bootblock-Runtime interface
module is moved to system memory and control is given to it. Determine
whether to execute serial flash.
The Runtime module is uncompressed into memory. CPUID information is
stored in memory.
Store the Uncompressed pointer for future use in PMM. Copying Main BIOS
into memory. Leaves all RAM below 1MB Read-Write including E000 and
F000 shadow areas but closing SMRAM.
Restore CPUID value back into register. Give control to BIOS POST
(ExecutePOSTKernel). See POST Code Checkpoints section of document for
more information.
System is waking from ACPI S3 state
OEM memory detection/configuration error. This range is reserved for
chipset vendors & system manufacturers. The error associated with this
value may be different from one platform to the next.
Description
Initialize the floppy controller in the super I/O. Some interrupt vectors are
initialized. DMA controller is initialized. 8259 interrupt controller is
initialized. L1 cache is enabled.
Set up floppy controller and data. Attempt to read from floppy.
Enable ATAPI hardware. Attempt to read from ARMD and ATAPI CDROM.
Disable ATAPI hardware. Jump back to checkpoint E9.
Read error occurred on media. Jump back to checkpoint EB.
Search for pre-defined recovery file name in root directory.
Recovery file not found.
Start reading FAT table and analyze FAT to find the clusters occupied by the
recovery file.
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