> -----Original Message----- > From: Andy Lutomirski [mailto:luto@xxxxxxxxxxxxxx] > Sent: Thursday, June 16, 2016 1:41 PM > To: Limonciello, Mario <Mario_Limonciello@xxxxxxxx> > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>; Andy Lutomirski > <luto@xxxxxxxxxx>; Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>; USB > list <linux-usb@xxxxxxxxxxxxxxx>; Mathias Nyman > <mathias.nyman@xxxxxxxxx>; Dominguez, Jared > <Jared_Dominguez@xxxxxxxx> > Subject: Re: Minor xhci issues (failed to peer) on Dell XPS 13 9350 (Skylake) > > On Sun, Mar 13, 2016 at 7:29 PM, Mario Limonciello > <mario_limonciello@xxxxxxxx> wrote: > > > > > > On 03/12/2016 02:33 PM, Andy Lutomirski wrote: > >> On Sat, Mar 12, 2016 at 11:35 AM, Andy Lutomirski <luto@xxxxxxxxxxxxxx> > wrote: > >> Got it. I was barking up the wrong tree. > >> > >> Q: What happens if _Q66 runs concurrently with itself: > >> > >> A: > >> > >> Method (_Q66, 0, NotSerialized) // _Qxx: EC Query > >> { > >> Acquire (PATM, 0x0064) > >> If ((ECRD != One)) > >> { > >> Return (Zero) > >> } > >> > >> NEVT () > >> Release (PATM) > >> Return (Zero) > >> } > >> > >> The first one acquires PATM. The second one fails to acquire PATM due > >> to the timeout, does something potentially harmful when it reenters > >> NEVT (not sure -- maybe it's fine), then blows up when it tries to > >> release PATM, which it doesn't hold. > >> > >> --Andy > > Andy, > > > > Our team has confirmed this mistake and will issue a fix in a future > > BIOS. For now if you want to build your own DSDT to see if this is > > causing your type-C problems the Release(PATM) will be inserted in the > > obvious location. > > > > FWIW this issue will affect many platforms in this generation. (XPS > > 9550, XPS 9350, Precision 5510, and more) > > > > FYI: the H_EC.CHRG issue seems to be fixed in 1.4.3. The PATM issue > is still there by inspection of the code, although I haven't gotten > unlucky enough to trigger it yet. Thanks for the heads up. I'll poke the team and find out if it was pushed out, or it was a different fix than previously planned. If you trigger it and it's still leading to any problems let me know. ��.n��������+%������w��{.n�����{���)�� jg��� �����ݢj����G���� ���j:+v���w�m������w�������h�����٥
