This allows the `usb` option to be used in the `boot:` parameter. Of
course there is not support for booting from a USB, but this allows for
a (probably much) further down the road addition.
This will break the current bios when booting from a network. However,
the bios is already broken in this manner, especially when
`BX_ELTORITO_BOOT` is not defined. The current bios code assumes and
hard codes the BEV entry to 4. However, if the `BX_ELTORITO_BOOT` define
is missing, the BEV will be added to the third entry, not the fourth
entry.
For the BIOS to be updated correctly, things like the following will
need to be updated instead of hard coded to `[4]`.
54961f0326/bochs/bios/rombios.c (L2205)
The following will need to be not hard coded to 4.
54961f0326/bochs/bios/rombios.c (L2253-L2257)
The following will need "usb" added.
54961f0326/bochs/bios/rombios.c (L2102)
The following assumes the next entry will be the fourth entry, not
checking to see if `BX_ELTORITO_BOOT` was defined.
54961f0326/bochs/bios/rombios.c (L10851-L10857)
The following comment will need to be updated.
54961f0326/bochs/bios/rombios.c (L8365-L8371)
As well as a few other fixes and updates.
This PR simply allows the value of '4' (`BX_BOOT_USB`) to be placed in
the boot sequence options, moving the network (`BX_BOOT_NETWORK`) to the
next number.
The boot sequence option still only allows three parameters.
`boot: cdrom, floppy, disk`
or
`boot: cdrom, usb, disk`
I don't think it is necessary to add a fourth.
---------
Co-authored-by: Volker Ruppert <Volker.Ruppert@t-online.de>
8fda7423d3