I'm certainly not an expert in this area, but I'd expect that all that a driver would need is the PCI card's base address. PC BIOS calls aren't available once an OS starts either, the OS basically extracts the hardware info it needs, loads the necessary driver, and then stops using BIOS calls. The VESA standard should specify how to find the VGA bios; that's all you really need.

LiveForIt wrote:
But I expect the standard entry point is the PC BIOS, because that where PCI card is registered after scanning the PCI bus for vendor id?s and product id?s, the video cards IO ports and memory maps are located some where else (but only the PC bios knows where that is if I?m right.)

They were removed, check the release notes of rtg.library version 41.4272. For example my Merlin supports planar modes but on AmigaO4 they are not available anymore.

A generic VGA, i.e. max. 640x480 4 bit planar, driver would have been possible that way, but since IIRC support for planar modes was removed in the AmigaOS4 version of Picasso96 that wont work either ... (but it could be that the planar modes were only removed from all drivers and not from Picasso96 itself).

billt wrote:
Here's another question toward a VESA generic driver. Is there a standard definition of VESA graphics registers, refresh rates, PLL settings, etc? Previous graphics like VGA and SVGA I think were completely standard everywhere, or at least to a large extent. If there is some absolute standard for all VESA registers, their offsets, sizes, field definitions, etc. then even without an x86 emulation it could be possible to write a driver to that standard register set instead of using x86 stuff, much like the current driver talks directly to Radeon specific registers or Voodoo driver talks directly to Voodoo specific registers.

If there is a standard register set it's the same kind of work as making or porting the Radeon open-source driver, but probably less as there's probably not much acceleration for lines, rectangles etc. to do as there is in chip-specific drivers.

billt wrote:
Sure, it'd be a lot of work to make a VESA driver, but I think it would be useful to have available if some issues could be solved.

You get into the question of how does the computer know what card is a graphics card or not to try the VESA diver with. If it's not already in the graphics card IDs list, do you ned to add your new card, and how? Or will there be some new field setting in uboot, and some list of PCI IDs you can get from uboot to know what the IDs of your new card are without booting Linux or something? You don't want the computer trying to run VESA driver on a sound card or SATA card etc but how will it know which is the graphics card? Wil it end up having the same problem with an unlisted graphics card as I have with my particular Radeon card, and thus not really solve anything?

We do have the x86 emulation in uboot that runs graphics BIOS. But it lacks some instructions, as can be sen if you try and boot with an AllInWonder 8500-DV card, which fails due to non-implemented instruction error in said emulation. Is there enough there to run BIOS subroutines?

Is it available to OS4 using this emulation? I don't know that too, but I am under the impression that anything uboot goes away when OS4 begins, and not much is handed off during the transition.