Re: cx88 pci_abort messages

From: Scott
Date: Mon Oct 08 2007 - 07:43:22 EST



On Oct 8, 2007, at 3:44 AM, Gerd Hoffmann wrote:

Scott wrote:
On Sat, 2007-10-06 at 12:48 -0600, Robert Hancock wrote:
Oct 2 21:59:32 htpc cx88[0]: irq mpeg [0x80000] pci_abort*
Oct 2 21:59:32 htpc cx88[0]/2-mpeg: general errors: 0x0008000

I assumed it was an interrupt issue based on the 'irq mepg' error, not a
DMA issue.

It's a DMA issue. The chip raised an irq to signal the error condition
to the driver, thats why it is printed by the irq handler. Happened
while streamimg mpeg data.

Havn't looked at the code for years now, but IIRC the 0x800000 is the
raw error code from some status register, pci_abort is the error bit in
clear text, meaning some PCI DMA transfer was aborted. No idea why
though ...

I went through and did the basics. Disabled SMP (it's a core 2 duo cpu), tried with noapic, nolapic settings, tried with pci=irqroute, and tried with acpi=off. Poking through the module code I noticd in cx88-mpeg.c the irq_debug option. I think this is the debug switch I want so I'll try to gather more info this week. At the very least it looks like it will help me walk through the code to get a better idea of what's going on.

--
Scott

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