Messages in this thread | ![/](/images/icornerl.gif) | | Date | Fri, 14 Apr 2006 17:48:30 +0300 | From | Muli Ben-Yehuda <> | Subject | Re: [PATCH] [2/2] POWERPC: Lower threshold for DART enablement to 1GB, V2 |
| |
On Fri, Apr 14, 2006 at 06:52:44AM +1000, Benjamin Herrenschmidt wrote: > On Thu, 2006-04-13 at 20:31 +0300, Muli Ben-Yehuda wrote: > > On Thu, Apr 13, 2006 at 11:07:12AM -0500, Olof Johansson wrote: > > > > > Walking the DT means we need to hardcode it on PCI IDs, since the Apple > > > OF doesn't give the Airport device a logical name. It's probably easier > > > to implement than walking PCI, but we'd need to maintain a table. My > > > vote is for PCI walking, I'll give that a shot over the weekend. > > > > Cool! bonus points if you do it in drivers/pci and we can steal it > > easily for Calgary on x8-64 :-) > > How so ? Anything remotely related to the iommu is totally different... > Besides, on x86-64, laptops _are_ more common, and thus the problem of > cardbus cards is much more significant.
What I had in mind is an interface that given a PCI bridge will tell you what's the most restrictive DMA mask for a device on that bridge, so that you'll know whether you need to enable the IOMMU for that bridge. I'll even settle for a function that tells you what's the most restrictive DMA mask in the system, preiod. There's nothing inherently arch specific about this.
(and as a side note, the IOMMU we are working on on x86-64 is Calgary, which is actually roughly the same chipset used in some PPC machines...)
Cheers, Muli -- Muli Ben-Yehuda http://www.mulix.org | http://mulix.livejournal.com/
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| ![\](/images/icornerr.gif) |