Re: bge(4) one packet wedge

On Wed, Aug 23, 2006 at 12:53:49PM -0700, David Christensen wrote:
This "lost interrupt" type of problem is addressed by the use of the
status_tag
field in the status block. (Listed as bge_rsvd0 in the bge_status_block
structure).
Everytime the status block is updated a new tag value is written to the
status block.
When the ISR starts the driver should record the status_tag value. At
the end
of the ISR, the driver should compare the current status_tag value is
the status
block with the value recorded on entry to the ISR. If the values are
the same
then no additional status block updates have occurred so there shouldn't
be
any packets hanging around. If the values are different then additional
packets
or completions are waiting around so the ISR should loop around again.
At the
end of the ISR the driver will write the status_tag value it last
handled to a
mailbox register, letting the hardware know the last status block update
handled.
If necessary the hardware will generate a new interrupt and start the
process over
again.

This entire process should be included in the Linux driver, I don't see
it being
used in the bge driver (bge_intr()).


Hi,

I have a question too.
How we know generated interrupt is ours?
It seems that status block could be updated before/after generation
of an interrupt. If the interrupt is shared with other devices
what is correct way to know the origion of the interrupt?

--
Regards,
Pyun YongHyeon
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