Re: Interrupt stom on cardbus device

On Sat, Feb 28, 2009 at 11:50:13AM -0600, Robert Noland wrote:
> On Sat, 2009-02-28 at 20:38 +0300, Nasonov Sergey wrote:
> > > Hrm, the intel driver is very noisy.  If the problem really is INTx,
> > > then the drm debugging won't know anything about that.  Could you try
> > > that patch that I posted later, without this patch to i915.  I've
> > looked
> > > over the linux pci code and they do disable INTx when enabling MSI.
> > > 
> > > I stuck the patch up as
> > > http://people.freebsd.org/~rnoland/pci_disable_intx.patch
> > 
> > Great! After applying this patch the problem was resolved. Switch to VT
> > an then back to X11 now work fine. Thanks!
> 
> Can you confirm that:
> 
> 1. Interrupts are still working (the msi ones)
> 2. Interrupts are still working for other devices on the shared INTx
> 
Yes (me too).
I haven't noticed that (no console message 'interrupt storm', perhaps
the system is too fast :).

vgapci0_at_pci0:0:2:0:     class=0x030000 card=0x82761043 chip=0x29c28086 rev=0x02 hdr=0x00
    vendor     = 'Intel Corporation'
    device     = '(Bearlake) Integrated Graphics Controller'
    class      = display
    subclass   = VGA

vmstat -i with:
~> uname -a
FreeBSD wep4035 8.0-CURRENT FreeBSD 8.0-CURRENT #0: Sat Feb 28 22:23:23 CET 2009     root_at_wep4035:/usr/obj/usr/src/sys/GENERIC  amd64

interrupt                          total       rate
irq1: atkbd0                       35447          0
irq6: fdc0                             1          0
irq16: uhci0+                 1286979669      13345
irq18: uhci2 ehci*                 46833          0
irq20: fwohci0                         2          0
irq22: atapci1                    835480          8
cpu0: timer                    192790855       1999
irq256: vgapci0                   125358          1
irq257: hdac0                         38          0
irq258: mskc0                    1728607         17
cpu1: timer                    192779996       1999
Total                         1675322286      17372

vmstat -i with the same sources and your patch:

interrupt                          total       rate
irq1: atkbd0                         505          3
irq6: fdc0                             1          0
irq16: uhci0+                      12191         72
irq18: uhci2 ehci*                   837          4
irq20: fwohci0                         2          0
irq22: atapci1                      2410         14
cpu0: timer                       334089       1988
irq256: vgapci0                     2064         12
irq257: hdac0                         39          0
irq258: mskc0                        103          0
cpu1: timer                       324595       1932
Total                             676836       4028

Thanks!
Alexey.