Date: Wed, 10 Apr 2013 10:28:38 +0400 From: Lev Serebryakov <lev@FreeBSD.org> To: John Baldwin <jhb@freebsd.org> Cc: Adrian Chadd <adrian@freebsd.org>, freebsd-current@freebsd.org, Poul-Henning Kamp <phk@phk.freebsd.dk> Subject: Re: Intel D2500CC motherboard and strange RS232/UART behavior Message-ID: <1659145198.20130410102838@serebryakov.spb.ru> In-Reply-To: <201304091658.22810.jhb@freebsd.org> References: <229402991.20130407172016@serebryakov.spb.ru> <201304091608.09257.jhb@freebsd.org> <105818341.20130410004451@serebryakov.spb.ru> <201304091658.22810.jhb@freebsd.org>
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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@FreeBSD.org>
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