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.
const char *. Originally I was going to add casts from const char * to
char * in some of the pci device drivers, but the reality is that the
pci device probes return constant quoted strings.
base register that controls Ultra-DMA, so we need to examine all possible
base registers instead of just giving up at the first empty one.
Also, looking at the source code to the BIOS, I see that they are also
checking for 0xffffffff as an invalid value so do the same. Stefan may like
to clean this up, but at least now I can find my PCI IDE registers.
Disable DPARCKEN in the DSCOMMAND0 register on the aic7890/91/96/97.
Parity checking is broken for some chip/MB combinations and this
is the work around recommended by Adaptec.
dpt_pci.c:
Remove a superflous '{' that prevented DPT_ALLOW_MEMIO from working.
pcireg.h:
Add a definition for Parity Error Reponse bit in the PCI Space
command register.
routines are necessary to allow the use of certain types of hardware on
the alpha, particularly a Myrinet card.
Submitted by: Andrew Gallatin <gallatin@cs.duke.edu>
and use this when masking/unmasking interrupts.
Maintain a mapping from (iopaic number, int pin) tuple to irq number,
and use this when configuring devices and programming the ioapics.
Previous code assumed that irq number was equal to int pin number, and
that the ioapic number was 0.
Don't let an AP enter _cpu_switch before all local apics are initialized.
Change the port address argument to pci_map_port to pci_port_t* which is
defined as u_int on the alpha, u_short on i386. This is a stopgap with a
hopefully limited lifetime.
Discussed with: Stefan Esser <se@freebsd.org>
FreeBSD/alpha. The most significant item is to change the command
argument to ioctl functions from int to u_long. This change brings us
inline with various other BSD versions. Driver writers may like to
use (__FreeBSD_version == 300003) to detect this change.
The prototype FreeBSD/alpha machdep will follow in a couple of days
time.
- Attempt to handle PCI devices where the interrupt is
an ISA/EISA interrupt according to the mp table.
- Attempt to handle multiple IO APIC pins connected to
the same PCI or ISA/EISA interrupt source. Print a
warning if this happens, since performance is suboptimal.
This workaround is only used for PCI devices.
With these two workarounds, the -SMP kernel is capable of running on
my Asus P/I-P65UP5 motherboard when version 1.4 of the MP table is disabled.
This introduce an xxxFS_BOOT for each of the rootable filesystems.
(Presently not required, but encouraged to allow a smooth move of option *FS
to opt_dontuse.h later.)
LFS is temporarily disabled, and will be re-enabled tomorrow.
of multiple PCI IDE controllers(Dyson), and some updates and cleanups from
John Hood, who originally made our IDE DMA stuff work :-).
I have run tests with 7 IDE drives connected to my system, all in DMA
mode, with no errors. Modulo any bugs, this stuff makes IDE look
really good (within it's limitations.)
Submitted by: John Hood <cgull@smoke.marlboro.vt.us>
device probe of a host to PCI bridge may modify that value, based on
its knowledge of device specific registers. This makes the Intel XXpress
work, as verified by: Terje Marthinussen <terjem@cc.uit.no>.
1) Stop at the first map register that contains a zero value.
2) When testing for the map size work up from low values, since
this works around a bug in some BusLogic SCSI card, which has
the 16 upper port base address bits hardwired to zero.
The config register dump printed in the bootverbose case has
been slightly rearranged.
reality. There will be a new call interface, but for now the file
pci_compat.c (which is to be deleted, after all drivers are converted)
provides an emulation of the old PCI bus driver functions. The only
change that might be visible to drivers is, that the type pcici_t
(which had been meant to be just a handle, whose exact definition
should not be relied on), has been converted into a pcicfgregs* .
The Tekram AMD SCSI driver bogusly relied on the definition of pcici_t
and has been converted to just call the PCI drivers functions to access
configuration space register, instead of inventing its own ...
This code is by no means complete, but assumed to be fully operational,
and brings the official code base more in line with my development code.
A new generic device descriptor data type has to be agreed on. The PCI
code will then use that data type to provide new functionality:
1) userconfig support
2) "wired" PCI devices
3) conflicts checking against ISA/EISA
4) maps will depend on the command register enable bits
5) PCI to Anything bridges can be defined as devices,
and are probed like any "standard" PCI device.
The following features are currently missing, but will be added back,
soon:
1) unknown device probe message
2) suppression of "mirrored" devices caused by ancient, broken chip-sets
This code relies on generic shared interrupt support just commited to
kern_intr.c (plus the modifications of isa.c and isa_device.h).
There are various options documented in i386/conf/LINT, there is more to
come over the next few days.
The kernel should run pretty much "as before" without the options to
activate SMP mode.
There are a handful of known "loose ends" that need to be fixed, but
have been put off since the SMP kernel is in a moderately good condition
at the moment.
This commit is the result of the tinkering and testing over the last 14
months by many people. A special thanks to Steve Passe for implementing
the APIC code!
This parameter is intended to allow new kernels to work with old LKM binaries,
provided the revision ID is incremented whenever the PCI LKM interface is
changed. The revision ID does not at all protect against changes in data
structures accesses by the driver.
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
bridges with support for 64 bit memory addresses and 32 bit I/O addresses).
The code is not complete. It ignores the upper half of the long addresses.
This is not a problem on PC compatible systems, but has to be fixed for
real computers.
Garrett Wollman sent me this code a few weeks ago for review, and I made
some significant changes, which he in turn accepted ...
In order to make use of these changes, a device entry has to added to /dev.
Submitted by: wollman
way it attaches multiple PCI buses directly to the CPU, instead of having
them hanging off from PCI to PCI bridges. This code is a hack, and will
be obsoleted by the planned rework of the PCI code, which will change the
dealing with PCI to PCI bridges and other special devices significantly.
The patch also adds a kern_devconf entry for PCI bus 0 which is assumed
to be a child of cpu0. The new PCI code will make it possible to hand out
the kern_devconf structure to a pci device being attached, since this is
(regretably, IMHO) required by a few ISA devices.
Finally there are new PCI ids for some Intel chip set devices, which had
already been known to 2.1.5R, but did not make it into -current. This closes
"kern/1558: PCI probe seems to have lost a device in -current".
should be <= than subordinate, not the other way around.
They are both true if the bridge is not cascaded (i.e., twin-channel
scsi/e-net adapters won't be affected by this bug), which is probably why
it was unnoticed until today.
- always use pci_conf_read() and pci_conf_write(). (This is required to
simulate non-existant devices in my system for PCI bridge code tests.)
- reorder some functions (put the main functions at the end).
- correct off by one bug in the code dealing with unitialized PCI to PCI
bridge chips. (Bug found by ASAMI Satoshi.)
- print function number for multi-function devices.
vm_offset_t is currently unsigned long but should probably be plain
unsigned for i386's to match the choice of minimal types to represent
for fixed-width types in Lite2. Anyway, it shouldn't be assumed
to be unsigned long.
I only fixed the type mismatches that were detected when I changed
vm_offset_t to unsigned. Only pointer type mismatches were detected.
port addresses (even though the PC architecture doesn't support them).
Add code to limit the I/O map size based on the lowest set bit of the
address. This cures the problem with the BT946C only having a 16 bit
map register, in voiolation of the PCI specs, without giving up the
general support of >65K port regions.
feature in the header type register, though it is required by the PCI spec.
This should correctly probe both functions of the Intel 82371FB chip,
without the need for a special case based on the device ID.
includes a hack in the probe code: the 82371FB is a multifuction
device, but doesn't properly set the configuration bit which
indicates this. So, we just hard-wire all 82371FBs as multifunction
devices.
This does not actually make the bus-master IDE stuff work, although
if anyone wants to work on that, I have the databooks that tell
how to use it.
#includes to get prototypes.
pci now uses a different interrupt handler type for interrupts that it
dispatches and the isa interrupt handler type for the interrupts that
it handles.
