[SeaBIOS] Reducing SeaBIOS kernel entry time

[Kevin O'Connor]

On Fri, Jul 03, 2015 at 11:43:22AM +0200, Peter Stuge wrote:
> If you want to optimize for the Linux special case then you should
> not be using anything BIOS-related at all.

There seems to be a common misunderstanding that supporting the BIOS
negatively impacts boot times.  This is not so - the BIOS is just a
library of functions in memory - they do not materially impact the
boot time if they are not used.

Instead, boot times are dominated by hardware initialization delays.
(I've run many tests, and I've found the core SeaBIOS code does not
add more than 1 or 2 ms to the boot time - at most.)  And, SeaBIOS is
actually quite good at optimizing hardware initialization time by
using its "thread" system (really coroutines).

-Kevin