* Eric W. Biederman <ebiederman(a)lnxi.com> [030929 23:48]:
> is there
a reason why the mptable creation uses dev_find_slot()
> to find the bridges instead of dev_find_device()? Since it does
> not even check whether the device it finds is the one it wants
> this sounds rather dangerous.
In the case of a specific motherboard it is safe, as long as all of
the upper level bridges are taken into account. dev_find_device,
is worse because you may have two devices with the same vendor
and device id.
But you can give it a starting point, and you probably want entries for
both of them anyways...?
It is on the todo list to generate all of this by
walking the device
tree. What we have now is a place holder that let's LinuxBIOS work
until we have generic code that will work for everyone.
Ok.. I think it's pretty easy doable if the bus number registers of the
bridges are filled reliably. Is this the case?
Is this an
internal convention, a hardware rule or just common sense
that the ISA bus is the last bus in the mptable? An ISA bus has no
bus number in the PCI view of things, does it?
Right. A lot of this was modeled on how existing mptables are setup.
I am not certain there needs to be a 1-1 mapping from bus numbers on
the pci bus to other bus numbers but it can't hurt. And the ISA can
pretty much go anywhere else.
Hanging it at the end of the list should not hurt then as it keeps all
the rest of constant.
backward compatibility interrupts */
bus_isa, 0x00, 0x02, 0x00);
Almost. Interrupts off of the LPC/ISA bus are the same because the bus
generates them. PCI interrupts that are routed through 8259 also vary.
I think the irq controller can also vary. Although it may be special
So the above works only if you use an ioapic? at least for opteron/linux
this is always the case. Linux/x86_64 wont boot with no ioapic enabled.
It must be left over. I have it yanked out of my
tree. After I finish
catching up on my email I will start synching the tress and kill it.
please do!! ;)
src entries for the different PCI slots confuse me a bit..
Is there a way to find out in the system how many pci slots a bridge
has, or should the bridge entry in the config file get an entry similar to:
register "slots" = 2
We should probably hang a ``slot'' device of the device tree to model this.
this is in the openfirmware kind of view a device node vs node property
consideration. Does a single slot need more information than the fact
that it's there?
All pci bridges have a maximum of 32 devices behind
them. And we need to know
which ones are actually devices.
We get that information during bus enumeration already, don't we?
SuSE Linux AG