RE: [PATCH]iwlan dma mapping read and write changes

[David Woodhouse <dwmw2@infradead.org>]

On Thu, 2009-02-12 at 00:10 +0200, Winkler, Tomas wrote:
> 
> >-----Original Message-----
> >From: Johannes Berg [mailto:johannes@sipsolutions.net]
> >Sent: Wednesday, February 11, 2009 11:50 PM
> >To: Winkler, Tomas
> >Cc: Yu, Fenghua; David Woodhouse; Ingo Molnar; Stephen Rothwell; Grumbach,
> >Emmanuel; Zhu, Yi; Chris Wright; LKML; iommu@lists.linux-foundation.org
> >Subject: RE: [PATCH]iwlan dma mapping read and write changes
> >
> >On Wed, 2009-02-11 at 22:47 +0100, Johannes Berg wrote:
> >> > >> Indeed the firmware/ucode write back to host memory to update retry
> >> > >> counter for APMDU packets. I'm not sure if this is needed for legacy
> >> > >> traffic, though.
> >> > >
> >> > >I don't think they can be seeing AMPDU packets since that is, well,
> >> > >broken?
> >> >
> >> > Currently I'm not aware of any other cases where memory is accessed
> >> > back but I may have not complete info.  Will be back with the answer
> >> > tomorrow.
> >>
> >> I don't think it really matters, since AMPDU packets will be fixed soon,
> >> and for those you know it's necessary (and the report says that under
> >> some other circumstances it's also necessary). Unless there'd be some
> >> benefit from using BIDI only when we know it'll be needed, and using
> >> TODEV in the other cases?
> >
> >Or if there's a firmware bug.
> 
> That's why it's better to clear the picture. 
> Fenghua
> What exact HW do you get this error?

Lenovo T400.

00:00.0 0600: 8086:2a40 (rev 07)
00:02.0 0300: 8086:2a42 (rev 07)
00:02.1 0380: 8086:2a43 (rev 07)
00:03.0 0780: 8086:2a44 (rev 07)
00:03.2 0101: 8086:2a46 (rev 07)
00:03.3 0700: 8086:2a47 (rev 07)
00:19.0 0200: 8086:10f5 (rev 03)
00:1a.0 0c03: 8086:2937 (rev 03)
00:1a.1 0c03: 8086:2938 (rev 03)
00:1a.2 0c03: 8086:2939 (rev 03)
00:1a.7 0c03: 8086:293c (rev 03)
00:1b.0 0403: 8086:293e (rev 03)
00:1c.0 0604: 8086:2940 (rev 03)
00:1c.1 0604: 8086:2942 (rev 03)
00:1c.2 0604: 8086:2944 (rev 03)
00:1c.3 0604: 8086:2946 (rev 03)
00:1c.4 0604: 8086:2948 (rev 03)
00:1d.0 0c03: 8086:2934 (rev 03)
00:1d.1 0c03: 8086:2935 (rev 03)
00:1d.2 0c03: 8086:2936 (rev 03)
00:1d.7 0c03: 8086:293a (rev 03)
00:1e.0 0604: 8086:2448 (rev 93)
00:1f.0 0601: 8086:2917 (rev 03)
00:1f.2 0106: 8086:2929 (rev 03)
00:1f.3 0c05: 8086:2930 (rev 03)
03:00.0 0280: 8086:4236 
04:00.0 0580: 8086:444e (rev 11)
15:00.0 0607: 1180:0476 (rev ba)
15:00.1 0c00: 1180:0832 (rev 04)

-- 
dwmw2