Reorder how the pci probing in handled. before adding devices, check to
see if the slot is a multi-function device to see if we should probe all
the functions.
Original idea by: imp
ia64-specific.
- When trying to re-route interrupts, don't change cfg->intline if the
re-route fails by returning an invalid vector. This fixes machines
without any way of routing interrupts such as older PC's without a
$PIR table.
We do not currently write the new intline value back to the hardware, but
we should. That will likely be added in a later commit.
Always route PCI interrupts on i386 UP machines. I was planning to enable
this for i386 anyways once SMP support is done. Having this enabled fixes
problems on many people's laptops.
Requested by: imp
(with other names) in the USB driver sources, but I felt that pcireg.h
should have a complete list - at least of classes and interfaces that we
know about and use.
command config register. At the present, this represents a nop
because these bits should have been set earlier in the process. In
the future, we'll only set these bits when the driver requests the
resource, not when the bus code detects the resource.
Reviewed by: mdodd
branches:
Initialize struct cdevsw using C99 sparse initializtion and remove
all initializations to default values.
This patch is automatically generated and has been tested by compiling
LINT with all the fields in struct cdevsw in reverse order on alpha,
sparc64 and i386.
Approved by: re(scottl)
pci busses implement this.
Also minor comment smithing in cardbus. Fix copyright to this year
with my name on it since I've been doing a lot to this file.
Reviewed by: jhb
We allow the request to go through if it matches either a prefetchable
or a non-prefetchable part of the bridge. We do not check to make
sure it is the right kind of memory because most drivers to not yet
properly set RF_PREFETCHABLE (only cardbus seems to do so, and I'm not
entirely sure it does it right). RF_PREFETCHABLE was invented for
cardbus, so hasn't been properly documented yet.
This is still overridable by hw.pci.allow_unsupported_io_ranges, but
the need for that is greatly reduced, especially for the nvida driver.
Approved by: re
Reviewed by: jhb and many testers
Submitted by: Matt Emmerton (although this has been reworked somewhat)
buses support querying the MAC address in a standard-for-that-bus way.
The base pci bus returns NULL for this IVAR always.
Submitted by: sam
Approved by: re (blanket for NEWCARD)
- If a PCI device is not present, then a 32-bit read_config() is going to
return 0xffffffff not 0xffff.
- For the 82454NX chipset, the MIOC that we read the bus numbers of the
various host-PCI bridges from is at function (slot) 0x10 not 0x0.
Approved by: re (rwatson)
across system suspends on the Intel 82371AB PCI-ISA bridge. On a
Sony Vaio C1XD that I have, these registers are not set correctly
after an ACPI resume. The result is that after resuming, a shared
IRQ is left in edge-triggered mode so the interrupt can later become
jammed in a state where the line remains asserted, but the handler
is never called.
Reviewed by: jhb
supported option and it disabled a whole 2 lines of bootverbose messages.
I wanted to see 1 of the messages (about the latency timers). This
is a wrong place to decode pci configurations, but the code is already
here and handles more details than pciconf(8).
when the first PCI bus attaches.
- Create /dev/pci during MOD_LOAD as well.
- Destroy /dev/pci during MOD_UNLOAD (not that you can kldunload pci, but
might as well get the code right)
- Add an ACPI PCI-PCI bridge driver (the previous driver just handled
Host-PCI bridges) that is a PCI driver that is a subclass of the generic
PCI-PCI bridge driver. It overrides probe, attach, read_ivar, and
pci_route_interrupt.
- The probe routine only succeeds if our parent is an ACPI PCI bus which
we test for by seeing if we can read our ACPI_HANDLE as an ivar.
- The attach routine saves a copy of our handle and calls the new
acpi_pcib_attach_common() function described below.
- The read_ivar routine handles normal PCI-PCI bridge ivars and adds an
ivar to return the ACPI_HANDLE of the bus this bridge represents.
- The route_interrupt routine fetches the _PRT (PCI Interrupt Routing
Table) from the bridge device's softc and passes it off to
acpi_pcib_route_interrupt() to route the interrupt.
- Split the old ACPI Host-PCI bridge driver into two pieces. Part of
the attach routine and most of the route_interrupt routine remain in
acpi_pcib.c and are shared by both ACPI PCI bridge drivers.
- The attach routine verifies the PCI bridge is present, reads in
the _PRT for the bridge, and attaches the child PCI bus.
- The route_interrupt routine uses the passed in _PRT to route a PCI
interrupt.
The rest of the driver is the ACPI Host-PCI bridge specific bits that
live in acpi_pcib_acpi.c.
- We no longer duplicate pcib_maxslots but use it directly.
- The driver now uses the pcib devclass instead of its own devclass.
This means that PCI busses are now only children of pcib devices.
- Allow the ACPI_HANDLE for the child PCI bus to be read as an ivar
of the child bus.
- Fetch the _PRT for routing PCI interrupts directly from our softc
instead of walking the devclass to find ourself and then fetch our
own softc.
With this change and the new ACPI PCI bus driver, ACPI can now properly
route interrupts for devices behind PCI-PCI bridges. That is, the
Itanium2 with like 10 PCI busses can now boot ok and route all the PCI
interrupts. Hopefully this will also fix problems people are having with
CardBus bridges behind PCI-PCI bridges not properly routing interrupts
when ACPI is used.
Tested on: i386, ia64
OOP speak, you would mark these as 'protected' members. Specifically:
- Make the pcib_softc struct public so it can be used by subclasses.
- Make pcib_{read,write}_ivar(), pcib_alloc_resource(), pcib_maxslots(),
and pcib_{read,write}_config() globals that can be used by subclasses.
- Make the pcib devclass a global variable.
- Move most of the pcib_attach() function into a global
pcib_attach_common() function that can be called by the attach routines
of subclasses.
Tested on: i386, alpha, sparc64, ia64
- Make the pci devclass a global variable.
- Add child devices in pci_attach() instead of pci_probe(). Change
pci_probe() to just check for a valid bus number from the associated
bridge and return -1000 if successful. This allows subclasses of the
PCI bus driver to override the generic driver.
- Move the code to load the vendor data into its own public function.
Really though, doing this at attach is just plain wrong. This should
really be done in the module load routine instead. As a side effect,
the 'busno' variable in pci_attach() is now no longer static (minor
bug that was harmless so far.)
- Change pci_add_children() to take an extra argument that is the size of
the device info structure passed to pci_read_device() and make it public
so subclasses of the PCI bus can call it in their attach routines.
- Move the bits to attach a probed PCI child to a PCI bus into a global
pci_add_child() function. This will allow subclasses that can detect
a PCI device not found in the normal PCI probe to add those devices in
their own attach routine. (I have seen this in the ACPI tree on my
laptop for example.) As a side effect, change the static function
pci_add_resources() to get the busno, slot, and func from the passed
in dinfo structure instead of requiring them as function arguments.
Tested on: i386, alpha, ia64, sparc64
code into cardbus and s/pci/cardbus. This exposes a few pci_*
functions that are now static.
This work is similar to work Justin posted to the mobile list about a
year or two ago, which I have neglected since then.
This is a subset of his current work with the multiple inheritance
newbus architecutre. When completed, that will eliminate the need for
pci/pci_private.h.
Similar work is needed for the cardbus_cis and pccard_cis code as well.
of I/O in 1.5. It looks like I got it right only for some of the
cases. Instead, allow ISA addresses as a special case. Most PCI
bridges decode this range. I need to investigate PCI bridges better
to know if this is always true or not, but for now assume that it is
since that seems to be the most common case.
# We need to allocate addresses better for the pccard stuff...
Submitted by: phk, mitsunaga-san
request to one that's supported by the bridge. I'm not 100% sure this
is correct, but it makes it easier for the cardbus bridge to allocate
its memory.
Similar code is needed for the I/O range. Also, I'm not sure if I
should be doing this based on memory or pmemory (but likely should do
it based on some flag that tells us to prefetch or not).
Talked about a long time ago with: msmith
with weird PCI-PCI bridge configurations to work. Defining
PCI_ALLOW_UNSUPPORTED_IO_RANGE causes the sanity checks to pass even
with out of range values.
Reviewed by: msmith
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.
Sorry john! (your next MFC will be a doosie!)
Reviewed by: peter@freebsd.org, dillon@freebsd.org
X-MFC after: ha ha ha ha
all alphas with devices behind ppb's. I'm working on a better solution now.
Note that all alphas that use per-platform interrupt mapping are broken
again (as they have been for several months)
breakage:
- call PCIB_ROUTE_INTERRUPT() regardless of how valid the intline looks.
Some alphas leave garbage in the intline and leave the intr mapping
to OS platform support routines that map slots/buses to intlines
- Down in the alpha pci code, first try platform.pci_intr_route() and
if it doesn't exist or returns garbage, just read the intline out of
config space.
tested on AS500 (garbage in intline) and UP1000 (PC-like, intline is valid)
Note that a nice little hack like the APIC_IO section of pci_cfgregread()
is not workable. This is because the calling interface for
alpha_pci_route_interrupt() requires us to figure out the bus/slot/etc
from a device_t. At pci_read_device() time, we don't have a device_t
for the bus/slot/func in question.
- Break out the /dev/pci driver into a separate file.
- Kill the COMPAT_OLDPCI support.
- Make the EISA bridge attach a bit more like the old code; explicitly
check for the existence of eisa0/isa0 and only attach if they don't
already exist. Only make one bus_generic_attach() pass over the
bridge, once both busses are attached. Note that the stupid Intel
bridge's class is entirely unpredictable.
- Add prototypes and re-layout the core PCI modules in line with
current coding standards (not a major whitespace change, just moving
the module data to the top of the file).
- Remove redundant type-2 bridge support from the core PCI code; the
PCI-CardBus code does this itself internally. Remove the now
entirely redundant header-class-specific support, as well as the
secondary and subordinate bus number fields. These are bridge
attributes now.
- Add support for PCI Extended Capabilities.
- Add support for PCI Power Management. The interface currently
allows a driver to query and set the power state of a device.
- Add helper functions to allow drivers to enable/disable busmastering
and the decoding of I/O and memory ranges.
- Use PCI_SLOTMAX and PCI_FUNCMAX rather than magic numbers in some
places.
- Make the PCI-PCI bridge code a little more paranoid about valid
I/O and memory decodes.
- Add some more PCI register definitions for the command and status
registers. Correct another bogus definition for type-1 bridges.
rather than finding our parent pcib and using its PCI_READ_CONFIG
method.
- Fix the defines for the 32-bit I/O decode registers, and properly
process the 16-bit versions. Now we will correctly check that I/O
resources behind the bridge are going to be decoded.
- Bring the quirk for the Orion PCI:PCI bridge in here (since it
seems to want to set the secondary/supplementary bus numbers).
- Use PCI_SLOTMAX rather than a magic number.
the ISA bus.
- Don't expect that a PCI:ISA bridge will have a correct class value;
if we're checking PCI IDs, only depend on these.
This should fix the loss of ISA on machines with PCI:EISA bridges like the
AS4100.
class/subclass, so give up trying to cull the list. Instead, complain
in the bootverbose case, but otherwise just accept that we will have to
carry this list of device IDs around.
- Improve the formatting for devices identified by the database.
- Fix the pcib_route_interrupt method definition, as an old version
snuck in here somehow 8(
- Remove a couple of the vendor/device IDs for PCI:ISA bridges which
correctly identify themselves.
Submitted by: peter
- Move PCI core code to dev/pci.
- Split bridge code out into separate modules.
- Remove the descriptive strings from the bridge drivers. If you
want to know what a device is, use pciconf. Add support for
broadly identifying devices based on class/subclass, and for
parsing a preloaded device identification database so that if
you want to waste the memory, you can identify *anything* we know
about.
- Remove machine-dependant code from the core PCI code. APIC interrupt
mapping is performed by shadowing the intline register in machine-
dependant code.
- Bring interrupt routing support to the Alpha
(although many platforms don't yet support routing or mapping
interrupts entirely correctly). This resulted in spamming
<sys/bus.h> into more places than it really should have gone.
- Put sys/dev on the kernel/modules include path. This avoids
having to change *all* the pci*.h includes.
like the args to the config space accessors these functions replaced.
This reduces the likelyhood of overflow when the args are used in
macros on the alpha. This prevents memory management faults when
probing the pci bus on sables, multias and nonames.
Approved by: dfr
Tested by: Bernd Walter <ticso@cicely8.cicely.de>
command register is too aggressive. Revert to the previous behaviour, but
leave the new behaviour available as an undocumented option. It's not
clear what the Right, Right Thing is to do here, but the more conservative
approach is safer.
#ifdef away the offending code until somebody with more newbus fu than
me can figure out where to put a default function that returns 255
without touching each alpha chipset driver..
i386/isa/pcibus.c. This gets -current running again on multiple host->pci
machines after the most recent nexus commits. I had discussed this with
Mike Smith, but ended up doing it slightly differently to what we
discussed as it turned out cleaner this way. Mike was suggesting creating
a new resource (SYS_RES_PCIBUS) or something and using *_[gs]et_resource(),
but IMHO that wasn't ideal as SYS_RES_* is meant to be a global platform
property, not a quirk of a given implementation. This does use the ivar
methods but does so properly. It also now prints the physical pci bus that
a host->pci bridge (pcib) corresponds to.
bus/slot/function numbers. The old PCI code used other markers or
something, but without it here under the new pci code it is very hard to
tell which device is which (this only affects bootverbose mode).
enable bit hasn't been set in the command register, set the bit and
honour the register. It seems that quite a few lazy BIOS writers
aren't bothering to do this, which upsets the existing code and causes
us to miss out on properly-configured devices.
the drivers.
* Remove legacy inx/outx support from chipset and replace with macros
which call busspace.
* Rework pci config accesses to route through the pcib device instead of
calling a MD function directly.
With these changes it is possible to cleanly support machines which have
more than one independantly numbered PCI busses. As a bonus, the new
busspace implementation should be measurably faster than the old one.
"options COMPAT_OLDPCI". This option already existed, but now also tidies
up the declarations in #include <pci/pci*.h>. It is amazing how much stuff
was using the old pre-FreeBSD 3.x names and going silently undetected.
not u_long. On i386's with 64-bit longs, returning u_longs indirectly
in (more than) the space reserved for uintptr_t's tended to corrupt the
previous frame pointer in the stack frame, so it was not easy to debug.
The type mismatches are hidden by the bogus cast in DEVMETHOD().
non-device code.
* Re-implement the method dispatch to improve efficiency. The new system
takes about 40ns for a method dispatch on a 300Mhz PII which is only
10ns slower than a direct function call on the same hardware.
This changes the new-bus ABI slightly so make sure you re-compile any
driver modules which you use.
it's options COMPAT_OLDISA and COMPAT_OLDPCI. This is meant to be a
fairly strong incentive to update the older drivers to newbus, but doesn't
(quite) leave anybody hanging with no hardware support. I was talking with
a few folks and I was encouraged to simply break or disable the shims but
that was a bit too drastic for my liking.
platform we're running on so we know how many bits to reserve at the top
end for the 'hose' value. It turns out that there's *just* enough room
to support all possible hoses on TurboLaser.
Reviewed by: gallatin@freebsd.org, dfr@free3bsd.org
from useful drivers such as the 3D DRI drivers I will be porting for
hardware accelerated OpenGL. The hardware will still be reported during
boot using the nomatch system.
Approved by: jkh
are using an old unconverted driver. Most (if not all) of the drivers
for common hardware are newbus these days. However, we don't want
to encourage people to take the easy way out and write new drivers
using the shims. This is just passive "encouragement".
Reviewed by: phk
attaching to the device via chip*, use the newbus nomatch method to report
the device. This leaves them unattached so that a driver can be easily
loaded to grab them later.
background ]
Rename sys/pci/pci_ioctl.h to sys/sys/pciio.h to make it easier for
userland programs to use this interface. Reformat the file, and add a
BSD-style copyright to it.
Add a new man page for pci(4). The PCIOCGETCONF, PCIOCREAD, and PCIOCWRITE
ioctls are documented, but the PCIOCATTACHED ioctl is not documented
because it is not implemented.
Change includes of <pci/pci_ioctl.h> to <sys/pciio.h> or remove them
altogether. In many cases, pci_ioctl.h was unused.
Reviewed by: steve
device_add_child_ordered(). 'ivars' may now be set using the
device_set_ivars() function.
This makes it easier for us to change how arbitrary data structures are
associated with a device_t. Eventually we won't be modifying device_t
to add additional pointers for ivars, softc data etc.
Despite my best efforts I've probably forgotten something so let me know
if this breaks anything. I've been running with this change for months
and its been quite involved actually isolating all the changes from
the rest of the local changes in my tree.
Reviewed by: peter, dfr
rather than an "it's mine!" so that other newbus-aware drivers can
bid for the device too. This should allow the sym driver to out-bid
the ncr driver for devices it supports without having to modify ncr.c
at all. ncr would then function as a catch-all.
pci_probe_nomatch, so it won't be in the way when loading USB as a module.
The reason for them being there in the first place is that every
motherboard comes with USB kit and this way it looks more pretty (peter).
The real solution will be to define some method of detaching a driver
after it has attached.
"rw" argument, rather than hijacking B_{READ|WRITE}.
Fix two bugs (physio & cam) resulting by the confusion caused by this.
Submitted by: Tor.Egge@fast.no
Reviewed by: alc, ken (partly)
* Change the hack used on the alpha for mapping devices into DENSE or
BWX memory spaces to a simpler one. Its still a hack and should be
a seperate api to explicitly map the resource.
* Add $FreeBSD$ as necessary.
Rather than teaching pci_ioctl about hoses, we just pass down a magic number
& let the platform code figure out what the hose is based on what the bus
number is.
concept approved by dfr
For unknown devices the output will now be
pci0: unknown card (vendor=0x109e, dev=0x0878) at 14.1 irq 19
instead of
pci0: unknown card DD^0878 (vendor=0x109e, dev=0x0878) at 14.1 irq 19
Before this change, the code used to take the PCI vendor id and translate it
into a three letter ASCII name.
For PnP devices, the vendor id _does_ map to a nice ASCII name
(eg Creative Labs PnP ID maps to "CTL", ESS PnP ID maps to "ESS")
But there is no such mapping for PCI devices, as can be seen by the
example above where the Brooktree PCI vendor ID maps to "DD^"
The PCI Special Interest Group confirmed they do not have any mappings
from vendor ID to ASCII.
have been there in the first place. A GENERIC kernel shrinks almost 1k.
Add a slightly different safetybelt under nostop for tty drivers.
Add some missing FreeBSD tags
Diskslice/label code not yet handled.
Vinum, i4b, alpha, pc98 not dealt with (left to respective Maintainers)
Add the correct hook for devfs to kern_conf.c
The net result of this excercise is that a lot less files depends on DEVFS,
and devtoname() gets more sensible output in many cases.
A few drivers had minor additional cleanups performed relating to cdevsw
registration.
A few drivers don't register a cdevsw{} anymore, but only use make_dev().
- device_print_child() either lets the BUS_PRINT_CHILD
method produce the entire device announcement message or
it prints "foo0: not found\n"
Alter sys/kern/subr_bus.c:bus_generic_print_child() to take on
the previous behavior of device_print_child() (printing the
"foo0: <FooDevice 1.1>" bit of the announce message.)
Provide bus_print_child_header() and bus_print_child_footer()
to actually print the output for bus_generic_print_child().
These functions should be used whenever possible (unless you can
just use bus_generic_print_child())
The BUS_PRINT_CHILD method now returns int instead of void.
Modify everything else that defines or uses a BUS_PRINT_CHILD
method to comply with the above changes.
- Devices are 'on' a bus, not 'at' it.
- If a custom BUS_PRINT_CHILD method does the same thing
as bus_generic_print_child(), use bus_generic_print_child()
- Use device_get_nameunit() instead of both
device_get_name() and device_get_unit()
- All BUS_PRINT_CHILD methods return the number of
characters output.
Reviewed by: dfr, peter
equivalent to SYS_RES_MEMORY for x86 but for alpha, the rman_get_virtual()
address of the resource is initialised to point into either dense-mapped
or bwx-mapped space respectively, allowing direct memory pointers to be
used to device memory.
Reviewed by: Andrew Gallatin <gallatin@cs.duke.edu>
This function is called for each device for which no driver
was found.
Output is similar to the eisa_probe_nomatch() function but with the
added benefit of displaying the assigned IRQ (since PCI gives us
this information up front.)
Output is like so:
pci0: unknown card CPQ0508 (vendor=0x0e11, dev=0x0508) at 11.0 irq 9
pci0: unknown card DFZ0508 (vendor=0x10da, dev=0x0508) at 11.0 irq 9
pci0: unknown card DBL0508 (vendor=0x104c, dev=0x0508) at 11.0 irq 9
pci0: unknown card DDM0011 (vendor=0x108d, dev=0x0011) at 11.0 irq 9
I'm not happy with the 3 lines of macro cruft that got added but
I consider it a temporary annoyance as those bits will be moved to
some place where PCI, EISA and ISAPNP code will be able to use them.
(Not surprisingly, this message is longer than the code in question.)
Reviewed by: peter, dfr
via an IBM PCI-PCI bridge (82351 or 82352 or 82353)
The driver must identify if it is on a secondary PCI bus, which is
created via the IBM PCI-PCI bridge. If it is, then it must initialise
the IBM PCI-PCI bridge correctly.
To do this, the following new functions are added.
Because they use the pcici_t tag, they are considered 2.2 compatibility APIs
pcici_t * pci_get_parent_from_tag(pcici_t tag);
int pci_get_bus_from_tag(pcici_t tag);
(The _from_tag suffix is used to prevent clashes with similarly named
newbus PCI API functions)
Submitted by: Anton Berezin <tobez@plab.ku.dk>
Reviewed by: Doug Rabson <dfr@nlsystems.com>
Reworked by: Me (roger)
The cdevsw_add() function now finds the major number(s) in the
struct cdevsw passed to it. cdevsw_add_generic() is no longer
needed, cdevsw_add() does the same thing.
cdevsw_add() will print an message if the d_maj field looks bogus.
Remove nblkdev and nchrdev variables. Most places they were used
bogusly. Instead check a dev_t for validity by seeing if devsw()
or bdevsw() returns NULL.
Move bdevsw() and devsw() functions to kern/kern_conf.c
Bump __FreeBSD_version to 400006
This commit removes:
72 bogus makedev() calls
26 bogus SYSINIT functions
if_xe.c bogusly accessed cdevsw[], author/maintainer please fix.
I4b and vinum not changed. Patches emailed to authors. LINT
probably broken until they catch up.
Reformat and initialize correctly all "struct cdevsw".
Initialize the d_maj and d_bmaj fields.
The d_reset field was not removed, although it is never used.
I used a program to do most of this, so all the files now use the
same consistent format. Please keep it that way.
Vinum and i4b not modified, patches emailed to respective authors.
The specific intent of this commit is to pave the way for importing
Compaq XP1000 support. These changes should not affect the i386 port.
Reviewed by: Doug Rabson <dfr@nlsystems.com>
(actually, he walked me through most of it & deserves more than reviewd-by
credit )
displace a real driver.
Revert rev 1.109.
Pick up a few things from elsewhere (a couple of SiS id's).
As an *experiment*, have the chip* driver claim (for reporting purposes)
IDE controllers if there isn't another PCI-aware ide or ata driver to
grab them. I've exported the match function since it could be used from
the ata-all.c code replacing ata_pcimatch() - but I have not touched the
ata code. I'd like to catch a few more devices this way, including USB
and other bridges etc.
style pci drivers with a simple one-line change to use a module that
registers itself under new-bus and should in theory enable just about all
of the pci drivers to be loadable (kldload and loader(8)) but without
having the impact of converting the APIs yet.
This also fixes the problem of having undefined variables when only
new-style pci drivers are present.
i386 platform boots, it is no longer ISA-centric, and is fully dynamic.
Most old drivers compile and run without modification via 'compatability
shims' to enable a smoother transition. eisa, isapnp and pccard* are
not yet using the new resource manager. Once fully converted, all drivers
will be loadable, including PCI and ISA.
(Some other changes appear to have snuck in, including a port of Soren's
ATA driver to the Alpha. Soren, back this out if you need to.)
This is a checkpoint of work-in-progress, but is quite functional.
The bulk of the work was done over the last few years by Doug Rabson and
Garrett Wollman.
Approved by: core
The previous code just ignored the invalid map register, but this gave
surprising results because of the way pci_map_port() associated the map
register offset supplied with a map entry in the map array.
using the new pci_map_int_right() variant of pci_map_int(). Fast
interrupts work for PCI devices if and only if they are exclusive.
(The PCI interrupt mux doesn't support fast interrupts and can't
support a mixture of fast and slow interrupts even in principle.)
Don't assume that intrmask_t == unsigned in pci_map_int().
memory address space rather than IO space.. reflect this when looking for the
interface revision register.
If this is not true for them all then we probably need some smarter code.
