> --- Ursprüngliche Nachricht --- > Von: Benjamin Herrenschmidt <[EMAIL PROTECTED]> > An: Gerhard Pircher <[EMAIL PROTECTED]> > Kopie: [EMAIL PROTECTED], [email protected] > Betreff: Re: AGPGART driver for ArticiaS - ioremap() problem > Datum: Tue, 17 Jan 2006 10:18:15 +1100 > > > Ah, okay. So at least the approach to use the Uninorth code was a step > > in the right direction. But that requires changes in the DRI and X > > server code, right? > > Not you shouldn't... there are 2 different things here. One is how you > access the GART table itself. One is how you access the AGP memory (the > memory that is bound to the GART). > > I'm not 100% sure what of the 2 above cases triggered an error with > ioremap, I'm not sure what approach should be used, because i don't know > what your chipset does. That's the problem: we don't have the datasheet for the ArticiaS. :-( But the driver initializes correctly with the Uninorth code now and with the DRI/DRM code changed. (The code in drm_vm.c checks for Apple's PCI vendor ID. Therefore I just added a check for MAI's PCI vendor ID.) But the X server freezes after the login screen is displayed (IIRC the mouse still works, but the keyboard is dead!?).
BTW: A "agp_special_page" is reserved in init.c. Is this page necessary for the DRI/DRM drivers to work with the Uninorth driver? I enabled this code snipped for the AmigaONE too to be on the safe side. :-) > I would need more infos about the hw there. But the basic idea is: > > - For the GART table, you don't need to ioremap it (which is generally > a way to have it non-cacheable I suppose). You can just flush cache > entries after populating them (see uninorth_insert_memory(), it flushes > first the pages that are being inserted in the GART as AGP memory is not > cacheable neither, and at the end of the function, flushes the GART > entry proper). There may be another problem: it seems that it is not possible to flush the TLB cache of the ArticiaS with a specific register setting. At least MAI didn't specify a bit for this purpose in the code. I have to do some reverse engineering here. :-) > - The AGP aperture itself. The main issue there is wether your chipset > makes the AGP aperture visible to the CPU or not. The Apple UniNorth one > doesn't for example, it;'s only visible to the graphic chip. That is why > the uninorth driver sets cant_use_aperture to 1. That forces the DRM to > generate AGP mappings by using the real memory pages and putting them > together into a virtual mapping instead of doing a direct mapping of the > AGP aperture on the bus. Most x86 chipsets however _can_, thus a simple > remapping of pages is enough. Good question! How would I have to modify the Uninorth driver to use a direct mapping of the AGP aperture on the bus? Thanks! Gerhard -- DSL-Aktion wegen großer Nachfrage bis 28.2.2006 verlängert: GMX DSL-Flatrate 1 Jahr kostenlos* http://www.gmx.net/de/go/dsl -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
