NCR53C815 vs Tulip: sharing IRQ fails

Gerard Roudier groudier@club-internet.fr
Wed Mar 24 15:33:48 1999



On Tue, 23 Mar 1999 jlewis@lewis.org wrote:

> On Mon, 22 Mar 1999, Hardware Stuff wrote:
> 
> > http://cesdis.gsfc.nasa.gov/linux/misc/irq-conflict.html looks like a
> > better answer.  Switching the SCSI driver from SA_INTERRUPT to
> > SA_SHIRQ seems to have worked fine.
> 
> Back when I had this problem, Gerard advised against messing with the NCR
> driver.  I figured I'd rather break ethernet than break a SCSI driver and
> ruin data.

Earlier driver versions didn't disable interrupts when entered in the
interrupt routine, based on the fact that on Linux 2.0 and earlier kernel
versions, the driver was entered with interrupt disabled when the
SA_INTERRUPT flag had been used for requesting the interrupt. So, just
removing this flag in those earlier driver versions was not enough. 
That's safe in all ncr53c8xx-3.* versions and all sym53c8xx-* versions,
and even user definable at boot up in latest ones.

Gérard.