Mark Nelson wrote: > On Sun, Sep 21, 2008 at 10:15 AM, George Spelvin <linux@xxxxxxxxxxx> wrote: >> "Grant Grundler" <grundler@xxxxxxxxxx> wrote: >>> On Sat, Sep 20, 2008 at 8:17 AM, George Spelvin <linux@xxxxxxxxxxx> wrote: >>>> I just got a couple of MSI KA92 (AMD 790FX-based) motherboards with >>>> 8 GiB of RAM each. I noticed on boot that the SB600 AHCI implementation >>>> had a 32-bit DMA limitation, and looking in the archives, it >>>> appears that folks from AMD think it doesn't need to be there. >>> URL? >>> Just want to be sure I'm looking at the same thread. >> "About forcing 32bit DMA patch for AMD690G(SB600)" >> http://marc.info/?t=120107450600001 > > It looks like the results from people testing it further never arrived... > >>From git commit a878539ef994787c447a98c2e3ba0fe3dad984ec ("ahci: > work around ATI SB600 h/w quirk"), it looks like the initial > idea was to limit each command to a maximum of 255 sectors (but > to still allow 64bit DMA), but according to a later commit > (4cde32fc4b32e96a99063af3183acdfd54c563f0; "ahci: SB600 > workaround is suspect... play it safe for now") this did not > solve the lockups. But there are references in the thread above > to broken MSI on the SB600 possibly being the cause of the problem, > and now that commit 22b5e7a74280deae560c20ee1a9b502b35181327 > ("ahci: SB600 ahci can't do MSI, blacklist that capability") has gone in > maybe this is why you're able to get 64bit DMA working? (although > we do need more hints on how to conclusively test this) Hmm... I doubt MSI has anything to do with 64bit DMA but then again anything is possible. Shane, anything came out of the testing? Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
