Intel D2500CC motherboard and strange RS232/UART behavior

[Lev Serebryakov]

Hello, John.
You wrote 10 апреля 2013 г., 0:58:22:

>>   Problem is, that every uart device now is independent from each
>>   other in good "OOP" style, and it looks like interrupt sharing we
>>   need one interrupt handler per irq (not per device), which will now
>>   about several UARTs. Something like "multiport" device, bot not
>>   exactly.
JB> No, the interrupt code itself will handle shared interrupts (it will
JB> call all handlers).  I think in practice that uart is setting
  And what will happen, if there is two UARTs asserting interrupt in
same time? First one returns "FILTER_HANDLED", will second handler be
called?

  ISA interrupt sharing IS NOT so simple. sio contains a lot of
 obscure code to work.

JB> INTR_EXCL or some such and/or uart doesn't set RF_SHAREABLE when
JB> allocating the IRQ.  It is probably the latter.  You could try just
JB> adding RF_SHAREABLE to the bus_alloc_resource_any() for the IRQ to
JB> uart and see if that fixes it.
        sc->sc_ires = bus_alloc_resource_any(dev, SYS_RES_IRQ, &sc->sc_irid,
            RF_ACTIVE | RF_SHAREABLE);

It is here.

-- 
// Black Lion AKA Lev Serebryakov <lev at FreeBSD.org>