Re: [PATCH] provide correct pci routing information in mptable

Gleb Natapov
2009-12-23T18:45:20Z

On Wed, Dec 23, 2009 at 01:11:43PM -0500, Kevin O'Connor wrote:
> Thanks Gleb.
>
> On Wed, Dec 23, 2009 at 05:29:25PM +0200, Gleb Natapov wrote:
> > - + sizeof(struct mpt_intsrc) * 18);
> > + + sizeof(struct mpt_intsrc) * 34);
> [...]
> > + foreachpci(bdf, max) {
> > + int pin = pci_config_readb(bdf, PCI_INTERRUPT_PIN);
> > + int irq = pci_config_readb(bdf, PCI_INTERRUPT_LINE);
> > + if (pin == 0)
> > + continue;
> > + mask |= (1 << irq);
> > + memset(intsrc, 0, sizeof(*intsrc));
> > + intsrc->type = MPT_TYPE_INTSRC;
> > + intsrc->irqtype = 0; /* INT */
> > + intsrc->irqflag = 1; /* active high */
> > + intsrc->srcbus = 0; /* PCI bus */
> > + intsrc->srcbusirq = (pci_bdf_to_dev(bdf) << 2) | (pin - 1);
> > + intsrc->dstapic = ioapic_id;
> > + intsrc->dstirq = irq;
> > + intsrc++;
> > + }
>
> Why only increase the allocated storage for intsrc by 16? The loop
> above seems like it could add a large number of entries.
>
Unfortunately we have to allocate all memory in advance. The table can
have max 4 entries per device (one entry for each pin), so 16 is enough
for 4 devices.

> Also, the foreachpci() macro will iterate over every PCI function -
> there could be 8 functions to a pci device which could lead to
> duplicates in the table (two pci functions on the same device could
> use the same irq pin).
>
Yes, correct. Need to rework this loop.

--
Gleb.