Messages in this thread |  | | Date | Sat, 1 Jun 1996 09:49:43 +0300 (EET DST) | From | Linus Torvalds <> | Subject | Re: SVGA kernel chipset drivers. |
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On Fri, 31 May 1996, Albert Cahalan wrote: > > Unlikely. The difference between a library driver running with > > video ram mmap()'d (ie direct access) and io port access and a > > kernel driver is probably that the kernel driver is slower due > > to syscall overhead. > > Nope, the kernel can provide a framebuffer device in /dev that > programs can mmap. IO port access is less critical. > > The real reasons for such a driver are reliability and security.
Could we PLEASE stop this framebuffer nonsense?
It's not going to happen. There are LOTS of cards that don't even _have_ framebuffers (and they are usually the really high-end ones, the ones that people will want support for in the future). If they _do_ have a framebuffer, then SVGAlib can do the mapping itself.
Finally, IO port acccess is not at all less critical. As far as I know, there are _no_ PC graphics cards that you can really program without using IO ports. Stuff like colourmaps etc are almost invariably done with IO port access on PC's.
Linus
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