On Wed, May 11, 2011 at 1:20 PM, Kevin O'Connor <ke...@koconnor.net> wrote: > On Wed, May 11, 2011 at 01:12:16PM +1000, Graeme Russ wrote: >> >> > for two or three graphics chipsets. SeaBIOS can initialize any VGA >> >> > option ROM, but then you need SeaBIOS in the loop. >> >> > Option ROMs are ageold technology and stupid, but they are still >> >> > firmly entrenched in PC hardware. A BIOS was always there so everyone >> >> > assumes it will always stay there, not very many question if >> >> > something better could be done. >> >> >> >> Would be interesting to investigate implementing a stub in U-Boot to >> >> initialise and use VGA option ROMs >> > >> > VGA option ROMs call BIOS functions. So, one needs a BIOS >> > implementation (eg, SeaBIOS) or an emulator for them (eg, in >> > coreboot). >> >> What does Linux do? i.e. if you boot Linux from coreboot, how does it >> output to the VGA console? I know it uses BIOS early on (before switching >> to protected mode) but what does it do after entering protected mode? > > In general, one enables the coreboot VGA option ROM emulation when > booting Linux directly from coreboot. >
Yes, I understand that - But how does Linux output to the VGA console after switching to Protected Mode? Does it still do BIOS calls? And what about all those Linux drivers in drivers/video - Would porting them (to U-Boot) elliminate the need for BIOS/Option ROMs Note: Please pardon my ignorance if these appear to be dumb questions - I really don't know how the guts of VGA console works Regards, Graeme _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
