[syslinux] Embedding com32 modules and ldlinux.sys into one file

[Sergii Kolisnyk]

Hi!

On 19/01/2016, Tal Lubko <tallubko at yahoo.com> wrote:
...
>
> - It will be probably much slower to load Linux image located on ROM
Not that slower, I think.

> If I understand you correctly, I'm going to flash the motherboard BIOS.
Yes, I got it.

...
> I don't understand completely what you wrote and probably lack some
> knowledge about protected mode, IO mode etc.
> Why does ROM disk should fit low memory?
A BIOS extension is always mapped into low memory.
And the maximum window size is assumed to be 64K.

Actually, this is the limit of 2 ready-to-flash implementations I mentioned,
ROMOS and ROMDSK, because they started as ISA bus option ROMs.
To use extended memory access, you should ROMify some other memdisk,
for example the syslinux one, or write your own.
Lanworks extended memory memdisk was 1.5 kB compared to low memory
0.5 kB one. All this concerns BIOS, not UEFI.
If you'll write your own romdisk, you could access the flash via flash
controller
IO ports instead  of extended memory addressing.

For UEFI you'll get protected mode and 32-bit or even 64-bit addressing
from the start. Maybe it already includes a ROMable memdisk, I don't know.

You can choose BIOS or UEFI mode depending on which is better
for the OS you're intending to load, and UEFI bootloader availability.

I think even for BIOS the GRUB could be a better choice to put into ROM.

Best regards,
Sergii