Weird PCI interrupt delivery problem (resolution, sort of)
Scott Long
scottl at samsco.org
Wed Jan 25 07:04:04 PST 2006
John Baldwin wrote:
> On Tuesday 24 January 2006 19:34, Craig Boston wrote:
>
>>On Tue, Jan 24, 2006 at 10:43:49AM -0500, John Baldwin wrote:
>>
>>>What if you do a read of the lapic before the write? Maybe doing 'x =
>>>lapic->eoi; lapic->eoi = 0;'?
>>
>>Reading the lapic before the write has no effect.
>>
>>Reading the lapic after the write makes it work.
>
>
> Hmm, perhaps the read forces the write to post? Scott?
>
Either that, or the read imposes enough delay to let whatever was
happening during the DELAY call work. I find it hard to believe that
uncached writes would get delayed like this. I've lost the original
posting on this, could you provide the dmesg and computer make/model
again?
Scott
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