On Tue, Oct 25, 2011 at 01:19:34AM +0200, Xavier Bachelot wrote: > On 10/24/2011 03:18 PM, Luc Verhaegen wrote: > > On Mon, Oct 24, 2011 at 12:18:20PM -0000, OpenChrome Trac wrote: > >> #417: Unable to map mmio BAR. Argument list too long (7) > >> -----------------------+---------------------------------------------------- > >> Reporter: brian | Owner: somebody > >> Type: defect | Status: closed > >> Priority: critical | Milestone: > >> Component: xdriver | Version: 0.2.904 > >> Resolution: wontfix | Keywords: > >> Blocking: | Blockedby: > >> -----------------------+---------------------------------------------------- > >> Changes (by brian): > >> > >> * cc: brian@… (added) > >> > >> > >> Comment: > >> > >> Replying to [comment:3 schlobinux]: > >> > > >> > No, it was not a known issue. > >> > >> Perhaps adding a hint in the Xorg log where the reported error is printed > >> that lowering memory might help would be useful to future victims. > >> > >> > This is a limitation of PCI, and it will need TTM support to work > >> properly. There's nothing that can be done about that currently. > >> > >> OK. Fair enough. But shouldn't that mean leaving this ticket open until > >> that work is done and this issue is properly resolved? > >> > >> > You shouldn't notice any performance regression. > >> > >> Great news, thanx! > >> > >> -- > >> Ticket URL: <http://www.openchrome.org/trac/ticket/417#comment:4> > >> openChrome <http://www.openchrome.org/> > >> The openChrome project > > > > Here's an idea.. Why doesn't openchrome try to only map 256MB? > > > > if (size > (256 << 10)) { > > xf86DrvMsg(..., "Only mapping the accessible first 256MB of %dMB > > available videoram.\n", size >> 10); > > size = 256 << 10; > > } > > > > This worked fine for radeonhd late july 2007, where i for the first time > > dealt with 1GB cards. > > > > You'd think that users would be happier with a working X, and a small > > note stating "we can only use 256MB", over a failing X, and someone > > stating: "somewhere, over the rainbow, we might have some infrastructure > > implemented which can actually use that much memory". > > > > Luc Verhaegen. > > > This probably could have been written more gently, but after all this > years, I can't say I'm surprised ;-) Thanks for the suggestion. > > Regards, > Xavier
And with a message like "Cannot use more than 256 MB of VRAM.\n", you open the door to a ton of "WAAH! I cannot use all my vram!!!!!" reports. Also, the directly mappable ram limitation does not go away with a memory manager, this is either a hardware limitation (without the resizable bar cap), or broken/missing pci(-e) support for resizable bars in X/system infrastructure. With a mm, you do however get to play tricks with mappings and translation tables. Amazingly, the remainder of your patch does seem correct. Luc Verhaegen. _______________________________________________ openchrome-users mailing list [email protected] http://wiki.openchrome.org/mailman/listinfo/openchrome-users Main page: http://www.openchrome.org Wiki: http://wiki.openchrome.org User Forum: http://wiki.openchrome.org/tikiwiki/tiki-view_forum.php?forumId=1
