Trivial bus implementation inspired by OpenBSD's pv(4) to attach devices
that don't need nor rely on a PCI or ISA bus.

branches: 1.123.2;
s/optionms/options/ in copy-pasted comment.

Add btvmei + btvmeii and vme to ALL.

Add a SELFRELOC kernel option for the sake of documentation clarity.

Instead of telling that x86/boot(8) reloc command needs a kernel able
to self relocate, we can tell it needs a kernel built with the
SELFRELOC option. This keeps the reader from wondering what could
make a kernel able to self relocate.

branches: 1.120.20;
make process_machdep.c included always since it provides register i/o used by
sys_process_getlwpstatus.c which is always included.

harmonize process_machdep.c inclusion.

Arrange so that no options COREDUMP and no options PTRACE work together.
Thanks to Paul Goyette for testing.

Revert "Merge convert_xmm_s87.c into fpu.c"

I am going to add ATF tests for these two functions, and having them
in a separate file will make it more convenient to build and run them
in userspace.

Merge the bouyer-xenpvh branch, bringing in Xen PV drivers support under HVM
guests in GENERIC.
Xen support can be disabled at runtime with
boot -c
disable hypervisor

branches: 1.115.4;
Rollback multiboot2 for amd64, as requested by core

branches: 1.114.2;
Add multiboot 2 support to amd64 kernel

Merge amd64func.S into cpufunc.S, and clean up.

branches: 1.112.4;
Added Microsoft Hyper-V support. It ported from OpenBSD and FreeBSD.

graphical console is not work on Gen.2 VM yet. To use the serial console,
enter "consdev com,0x3f8,115200" on efiboot.

Merge the [pgoyette-compat] branch

This change modifies the mainbus(4) entry point for all x86 sub-archs
in the following way:

i) It provides a unified entry point in
x86/x86/mainbus.c:mainbus_attach()
ii) It carves out the preliminary bus attachment sequence that is
common to all sub-archs into
x86/x86/mainbus.c: x86_cpubus_attach()
iii) It consolidates the remaining pathways as internal callee
functions so that these may be called piecemeal if required. A
special usecase of this is XEN PVHVM which may need to call the
native configure path, the xen configure path, or both.
iv) It moves the driver private data structures from
i386/i386_mainbus.c to an x86/ level one. This allows for other
sub-arch's to do similar, if needed. (They do not at the moment).
v) For dom0 kernels, it enables 'acpi0 at mainbus?' and
'acpi0 at hypervisorbus'. This serves two purposes:
a) To demonstrate the possibility of dynamic configuration tree
traversal ordering changes.
b) To allow for the common acpi_check(self, "acpibus") call in
x86/mainbus.c to not barf when it is called from the dom0 attach
path. We allow for the acpi0 device to be a child of mainbus with
the changes to amd64/conf/XEN3_DOM0 and i386/conf/XEN3PAE_DOM0
without actually probing further in the code. This path will later
be pursued in a PVHVM boot codepath.

There should be no operative changes with this change. If there are,
please complain loudly.

Move mainbus(4) driver files in various x86 sub-archs to name prefixed
versions. This allows us to further modularise them by unifying common
bus probe code in x86/x86/mainbus.c to be introduced next.

This commit has no functional changes. It is done for ease of
visibility of newer diffs in the queue.

KASLR is in files.kern now.

Move the MI parts of KASAN into kern/subr_asan.c. This file includes
machine/asan.h, which contains the MD functions. We use an include rather
than a plain C file, because we want GCC to optimize/inline some functions
into one single block.

The amd64 MD parts of KASAN are moved accordingly.

The naming convention we use is:

kasan_*
a generic kasan object, declared in subr_asan.c
kasan_md_*
an MD kasan object, declared in machine/asan.h, and used
in subr_asan.c
__md_*
an MD object, declared in machine/asan.h, and not used
outside

Overall this makes it easier to add KASAN support on more architectures.

Discussed with several people.

Add support for kASan on amd64. Written by me, with some parts inspired
from Siddharth Muralee's initial work. This feature can detect several
kinds of memory bugs, and it's an excellent feature.

It can be enabled by uncommenting these three lines in GENERIC:

#makeoptions KASAN=1 # Kernel Address Sanitizer
#options KASAN
#no options SVS

The kernel is compiled without SVS, without DMAP and without PCPU area.
A shadow area is created at boot time, and it can cover the upper 128TB
of the address space. This area is populated gradually as we allocate
memory. With this design the memory consumption is kept at its lowest
level.

The compiler calls the __asan_* functions each time a memory access is
done. We verify whether this access is legal by looking at the shadow
area.

We declare our own special memcpy/memset/etc functions, because the
compiler's builtins don't add the __asan_* instrumentation.

Initially all the mappings are marked as valid. During dynamic
allocations, we add a redzone, which we mark as invalid. Any access on
it will trigger a kASan error message. Additionally, the compiler adds
a redzone on global variables, and we mark these redzones as invalid too.
The illegal-access detection works with a 1-byte granularity.

For now, we cover three areas:

- global variables
- kmem_alloc-ated areas
- malloc-ated areas

More will come, but that's a good start.

Remove the X86PMC code I had written, replaced by tprof. Many defines
become unused in specialreg.h, so remove them. We don't want to add
defines all the time, there are countless PMCs on many generations, and
it's better to just inline the event/unit values.

branches: 1.104.2;
Merge convert_xmm_s87.c into fpu.c. It contains only two functions, that
are used only in fpu.c.

Mmh, don't compile spectre.c on Xen.

add an SPECTRE_V2_GCC_MITIGATION option to x86 kernels, that turns
on the GCC spectre v2 mitigation options.

XXX: pullup-8.
XXX: turn on in all kernels.

branches: 1.101.2;
Compile amd64_trap.S as a file instead of including it.

Since SVS is now defined in files.x86, remove it from files.amd64
and files.i386.

Now that SVS is defined in file.x86, do not repeat it here

Add a new option, SVS (for Separate Virtual Space), that unmaps kernel
pages when running in userland. For now, only the PTE area is unmapped.

Sent on tech-kern@.

Compile the prekern entry point only under KASLR.

Save maxv@ some work and put back the compat_13_sigreturn changes that allow
amd64 to run ancient i386 binaries.

Drop COMPAT_13 on amd64, already not enabled. Reduces the number of
critical places.

KASLR: add workarounds to compute the bootinfo VAs (use the direct map),
and don't use large pages yet. Both will be fixed later.

Add the prekern entry point in the kernel.

Merge into x86/.

Merge into x86/.

Don't include files.svr4 and files.svr4_32.

include opt_pmc.h

branches: 1.88.8;
Add support for hardware assisted watchpoints/breakpoints API in ptrace(2)

Add new ptrace(2) calls:
- PT_COUNT_WATCHPOINTS - count the number of available hardware watchpoints
- PT_READ_WATCHPOINT - read struct ptrace_watchpoint from the kernel state
- PT_WRITE_WATCHPOINT - write new struct ptrace_watchpoint state, this
includes enabling and disabling watchpoints

The ptrace_watchpoint structure contains MI and MD parts:

typedef struct ptrace_watchpoint {
int pw_index; /* HW Watchpoint ID (count from 0) */
lwpid_t pw_lwpid; /* LWP described */
struct mdpw pw_md; /* MD fields */
} ptrace_watchpoint_t;

For example amd64 defines MD as follows:
struct mdpw {
void *md_address;
int md_condition;
int md_length;
};

These calls are protected with the __HAVE_PTRACE_WATCHPOINTS guard.

Tested on amd64, initial support added for i386 and XEN.

Sponsored by <The NetBSD Foundation>

branches: 1.87.2;
Define MD start code at the top of files.${MACHINE} relying on config(1)'s
deterministic file output order. No need to define ${MD_OBJS} and its useless,
explicit compile rules.

fix compat paths.

add the two new compat files.

branches: 1.84.2;
Define "machdep" attribute and mark files (in amd64 and x86).

Since fpu.c is contained in every kernel, and it calls routines in
convert_xmm_s87.c we need to include convert_xmm_s87.c in all kernels.

Fixes building of kernels that do not have COMPAT_NETBSD32 defined.

Move sys/arch/amd64/amd64/fpu.c and sys/arch/amd64/include/fpu.h
into sys/arch/x86 in preparation for using the same code for i386.

Convert the amd64 build to use x86/cpu_extended_state.h so that the fpu
definitions match those of i386.
Mostly just structure and field renames, in addition:
1) process_xmm_to_s87() and process_s87_to_xmm() moved into
x86/convert_xmm_s87.c so they can be used by amd64's netbsd32 code.
2) The linux signal code simplified to use a structure copy for ths fxsave
data - it matches the hardware definition and won't change.

A few "isa" files are so tightly integrated into the x86 platform code
as to not really be part of the optional isa bus autoconf machinery.

Allows configuring a kernel like so:

include "arch/amd64/conf/GENERIC"
no isa

branches: 1.79.2; 1.79.8;
Enable sljit in amd64 kernel and modules.

Remove references to VM86 from the amd64 kernel configs.
VM86 mode isn't supported while in long mode.

Remove bpf_jit which was ported from FreeBSD recently.

It will soon be replaced with the new bpfjit kernel module.

branches: 1.76.2;
Add BPF JIT compiler, currently supporting amd64 and i386. Code obtained
from FreeBSD. Also, make few BPF fixes and simplifications while here.
Note that bpf_jit_enable is false for now.

OK dyoung@, some feedback from matt@

Merge i386 and amd64 version of db_memrw.c.

Use this opportunity to skip calculating the VA of the page. Let the CPU
deal with the invalidation itself through invlpg + destination address to
avoid converting between canonical/non canonical forms.

branches: 1.74.4;
Add compat_svr4 hooks, this does not work yet.

branches: 1.73.2;
Welcome to 5.99.53! Merge rmind-uvmplock branch:

- Reorganize locking in UVM and provide extra serialisation for pmap(9).
New lock order: [vmpage-owner-lock] -> pmap-lock.

- Simplify locking in some pmap(9) modules by removing P->V locking.

- Use lock object on vmobjlock (and thus vnode_t::v_interlock) to share
the locks amongst UVM objects where necessary (tmpfs, layerfs, unionfs).

- Rewrite and optimise x86 TLB shootdown code, make it simpler and cleaner.
Add TLBSTATS option for x86 to collect statistics about TLB shootdowns.

- Unify /dev/mem et al in MI code and provide required locking (removes
kernel-lock on some ports). Also, avoid cache-aliasing issues.

Thanks to Andrew Doran and Joerg Sonnenberger, as their initial patches
formed the core changes of this branch.

branches: 1.72.2;
Merge db_trace for x86. From: Vladimir Kirillov proger at wilab dot org dot ua

Don't need x86_stub.c here, we'll pick it up from files.x86.

Clean up excessive #ifdef'age of NMI trap handling for amd64/i386/xen.
Handle NMI in all Xen kernels.

branches: 1.69.2;
Unify i386 and amd64 procfs MD code into x86.

branches: 1.68.2; 1.68.4;
Split mc146818-related functions from clock.c into rtc.c.
Call rtc_set_ymdhms() from xen/xen/clock.c:xen_rtc_set() for xen3 dom0
kernels as the Xen3 hypervisor doesn't write the new date/time to the CMOS
by itself.
Now a XEN3_DOM0 kernel properly updates the CMOS time.

Added SD/MMC support from OpenBSD.
tested on i386, amd64 at current-users ML by pgoyette@.
tested on zaurus by myself.

- Add macros to handle (some) trapframe registers for common x86 code.
- Merge i386 and amd64 syscall.c into x86. No functional changes intended.

Proposed on (port-i386 & port-amd64). Unfortunately, I cannot merge these
lists into the single port-x86. :(

Merge i386 and amd64 ipifuncs.c into x86. No functional changes intended.
XXX: fpu #ifdefs are ugly (should be revisited at some point).

Merge i386 and amd64 vm_machdep.c into x86. No functional changes intended.
Note: some #ifdefs will be removed with macros.

Merge/move core_machdep.c into x86, no difference between i386 and amd64.

Don't set version deep in the source tree if it's older than the one in
conf/files.

branches: 1.61.4;
Make the emulations, exec formats, coredump, NFS, and the NFS server
into modules. By and large this commit:

- shuffles header files and ifdefs
- splits code out where necessary to be modular
- adds module glue for each of the components
- adds/replaces hooks for things that can be installed at runtime

branches: 1.60.4; 1.60.6; 1.60.8; 1.60.12;
Simplify x86 identcpu code, and share between i386/amd64.

branches: 1.59.2; 1.59.4; 1.59.6;
Implement an optimized, preemption-safe asm version of tsc_get_timecount().
The C version needs work to be preemption safe. Cuts the clock cycles
for microtime() from 950 down to 300 on a Pentium D.

branches: 1.58.2; 1.58.6;
Since files.wscons et al. are included by ~all ports anyway, include
them in the mi "files" file, and remove include statements from md files.
These shouldn't pull in additional kernel code when not in use, so it
shouldn't do any harm except a risk of namespace collisions which
should be easy to fix.

Fix flags: cpu_in_cksum should modify cpu_in_cksum.S, not cpufuncs.S.

Refactor in_cksum/in4_cksum/in6_cksum implementations:
- All three functions are included in the kernel by default.
They call a backend function cpu_in_cksum after possibly
computing the checksum of the pseudo header.
- cpu_in_cksum is the core to implement the one-complement sum.
The default implementation is moderate fast on most platforms
and provides a 32bit accumulator with 16bit addends for L32 platforms
and a 64bit accumulator with 32bit addends for L64 platforms.
It handles edge cases like very large mbuf chains (could happen with
native IPv6 in the future) and provides a good base for new native
implementations.
- Modify i386 and amd64 assembly to use the new interface.

This disables the MD implementations on !x86 until the conversion is
done. For Alpha, the portable version is faster.

Remove options MATH_EMULATE.

Add assembler version of in_cksum. Thanks to ad@ for his time as
peep hole optimiser. This is 30% faster than the portable C version
for checksumming 64byte and larger mbufs and as fast as or slightly
faster for shorter mbufs (with a high variance).

Add MODULAR option. Include kernel linker stuff if MODULAR.

Add PHYSMEM_MAX_ADDR and PHYSMEM_MAX_SIZE options. This limit physical
memory based on overall size (useful for debugging to keep core dumps
small) or maximum address (when using devices with bus dma limits).
Contrary to REALBASEMEM and REALEXTMEM, they still use the BIOS memory
map and can therefore deal with fragmented memory.

Add new IPI for saving CPU state explicitly, share high-level part of
ACPI wakeup code and teach it how to start the APs again. As a side
effect the CPU_START interface allows choosing between different
bootstrap codes more easily now.

branches: 1.50.2;
Merge jmcneill-pm branch.

branches: 1.49.2; 1.49.4;
Pull up the bouyer-xenamd64 branch to HEAD. This brings in amd64 support
to NetBSD/Xen, both Dom0 and DomU.

branches: 1.48.2;
Share pcib(4) and amdpcib(4) between i386 and amd64; one copy is enough.

- Share pchb(4) between i386 and amd64; one copy is enough for both.
- Move some of the x86 PCI devices into x86/pci/files.pci.
- Add more x86 stuff into x86/conf/files.x86.

ok joerg.

merge yamt-x86pmap branch.

- reduce differences between amd64 and i386. notably, share pmap.c
between them. it makes several i386 pmap improvements available to
amd64, including tlb shootdown reduction and bug fixes from Stephan Uphoff.
- implement deferred pmap switching for amd64.
- remove LARGEPAGES option. always use large pages if available.
also, make it work on amd64.

Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree. Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches. The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

branches: 1.44.2;
x86 changes for pcc and LKMs.

- Replace most inline assembly with proper functions. As a side effect
this reduces the size of amd64 GENERIC by about 120kB, and i386 by a
smaller amount. Nearly all of the inlines did something slow, or something
that does not need to be fast.
- Make curcpu() and curlwp functions proper, unless __GNUC__ && _KERNEL.
In that case make them inlines. Makes curlwp LKM and preemption safe.
- Make bus_space and bus_dma more LKM friendly.
- Share a few more files between the ports.
- Other minor changes.

branches: 1.43.2;
Merge most x86 changes from the vmlocking branch, except the threaded soft
interrupt stuff. This is mostly comprised of changes to the pmap modules to
work on multiprocessor systems without kernel_lock, and changes to speed up
tlb shootdowns.

branches: 1.42.2;
Some changes for the ichlpcib driver:

- Moved to x86/pci, so that EM64T systems running NetBSD/amd64 can use it.
- Added support for the TCO on ICH6 or newer chipsets, adapted from
FreeBSD.
- Added timecounter support for the power management timer, adapted from
OpenBSD.
- Plus some misc/cosmetic changes.

Thanks to yukonbob on irc@freenode for testing the TCO part on ICH4-M.
Tested by me with ICH7 too.

Add support agp_amd64. Imported from FreeBSD.

branches: 1.40.2; 1.40.4; 1.40.8;
Remove leftover netns stuff.

Add (commented-out) support for IPMI on amd64--pretty much copied straight
from i386.

merge yamt-idlelwp branch. asked by core@. some ports still needs work.

from doc/BRANCHES:

idle lwp, and some changes depending on it.

1. separate context switching and thread scheduling.
(cf. gmcgarry_ctxsw)
2. implement idle lwp.
3. clean up related MD/MI interfaces.
4. make scheduler(s) modular.

branches: 1.37.2;
Share the sysarch stuff between the x86 ports. PR kern/36046.

include files.wsfb

Erm, remove a local change committed accidentally in previous.

ALL: Enable INTEL_ONDEMAND_CLOCKMOD.
GENERIC: Add INTEL_ONDEMAND_CLOCKMOD disabled by default.

branches: 1.33.2; 1.33.4;
High Precision Event Timer driver, following Intel specifications.

Allow attachement at both ACPI (hpet@acpi) and AMD8111 LPC Controller
(hpet@amdpcib).

Requested by xtraeme, and tested by a few users.

clean up how cpus and ioapics are attached at the mainbus:
Seperate "cpubus" and "ioapicbus" -- while they share a common "address
space" (the apic id), the kernel doesn't use this fact. There are different
data passed to cpus and apics, which caused some ugly polymorphism. This
also saves the special "submatch" functions needed to distingush cpus
and ioapics for autoconf. (And it makes that "apid" locators wired
in the kernel configuration are honored now; this allows one to dumb down
an mp box to singleprocessor by userconfig.)
Print "apid" locators in the buses "print" function "as everyone does",
so the per-port cpu drivers don't need to do it.
Being here, constify "struct cpu_functions" and g/c the unused MP_PICMODE
flag.

branches: 1.31.2;
Merge newlock2 to head.

Attach agp too.

branches: 1.29.2; 1.29.4; 1.29.6;
add bluetooth support to amd64 port, built by default in GENERIC kernels

branches: 1.28.2;
switch to a common clock.c

* Do not change struct powernow_pst_s (I added another member in my
previous patch) and this MUST be of that size, otherwise the tables
won't be found.

* powernow_k8.c moved into x86/x86, it should work both i386 and amd64.

* Added more DPRINTFs needed to found the first problem.

* Create "machdep.powernow.frequency" again, I can't remember why I
removed frequency... it should work with estd now.

* Do not try to call k[78]_powernow_init() if cpu is not AMD (thanks
to christos).

And more things I can't remember, but this time it will work in
Athlon 64 cpus and it won't crash in EM64T cpus.

AMD PowerNow!/Cool`n'Quiet driver for NetBSD/amd64,
adapted from OpenBSD.

Tested on a few machines:

http://bigbird.dohd.org:3021/NetBSD/dmesg
http://www.bsd.org.il/netbsd/acpi/dmesg

Thanks to cube, elad and others for testing and fixes.

Enabled by default on GENERIC.

kern/33961: add kgdb support and remove some redundant (and incorrect) register
offset definitions from reg.h

include files.apm

branches: 1.23.2;
convert to timecounters (from branch simonb-timecounters)

branches: 1.22.2;
Convert existing ath users to new Makefile, except for amd64, which needs
the rules due to needing to conditionally postprocess the HAL object file.

Macppc needs a a non-ELF HAL (EABI) object, so take care of that by default
in the atheros include file.

branches: 1.21.2; 1.21.4; 1.21.6;
Share Intel hardware random number generator support between amd64 and
i386 port. This will benefit EM64T systems using Intel i9xx chipsets.

Add initial (but unfinished) COMPAT_LINUX32 for amd64. This is good enough so
that the i386 license manager part of amd64 version of Fluent works.

While I'm here, add SysV IPC to COMPAT_LINUX/amd64

branches: 1.19.2; 1.19.4; 1.19.6;
Add boilerplate for cardbus support.

merge ktrace-lwp.

Add config goo for ath. Tested with a PCI card, detected as:

ath0 at pci0 dev 10 function 0
ath0: interrupting at ioapic0 pin 17 (irq 5)
ath0: 11a rates: 6Mbps 9Mbps 12Mbps 18Mbps 24Mbps 36Mbps 48Mbps 54Mbps
ath0: 11b rates: 1Mbps 2Mbps 5.5Mbps 11Mbps
ath0: 11g rates: 1Mbps 2Mbps 5.5Mbps 11Mbps 6Mbps 9Mbps 12Mbps 18Mbps 24Mbps 36M bps 48Mbps 54Mbps
ath0: mac 5.9 phy 4.3 radio 3.6

Cardbus untested, so it is commented out.

branches: 1.16.2;
Move linux_trap.c from sys/arch/i386/i386 to sys/arch/x86/x86, and share
it. Remove the amd64 linux_trap.c (which was just a stub with a printf
anyway).

Fix up COMPAT_LINUX support for amd64. Still a work in progress, not
usable yet ("Hello World" runs, but many other things do not work).

remove the (superfluous) definition of "cpu" as an interface attribute

Phase out the use of a string as first "attach args" member to control
which bustype should be attached with a specific call to config_found()
(from a "mainbus" or a bus bridge).
Do it for isa/eisa/mca and pci/agp for now. These buses all attach to
an mi interface attribute "isabus", "eisabus" etc., and the autoconf
framework now allows to specify an interface attribute on config_found()
and config_search(), which limits the search of matching config data
to these which attach to that specific attribute.
So we basically have to call config_found_ia(..., "foobus", ...) where
such a bus is attached.
As a consequence, where a "mainbus" or alike also attaches other
devices (eg CPUs) which do not attach to a specific attribute yet,
we need at least pass an attribute name (different from "foobus") so
that the foo bus is not found at these places. This made some minor
changes necessary which are not obviously related to the mentioned buses.

Adapt for new aapic.c location.

the whole sigcode business is COMPAT_16 only

remove sigcontext-style signal delivery code

Abstract the interface between pckbc(4), and the pckbd(4) and pms(4)
drivers that attach to it. This allows for other host interface chips
that use the same keyboards and mice, such as the ones in the ARM
IOMD20, ARM7500, and SA-1111. The PC-compatible driver is still
called pckbc(4), and the new abstraction layer is "pckbport", so the
child devices have moved from sys/dev/pckbc to sys/dev/pckbport, which
also contains some code shared between all host controllers. To avoid
incompatibility, pckbdreg.h is still installed in
/usr/include/dev/pckbc.

In theory, this shouldn't cause any behavioural changes in the drivers
concerned. Thy just use rather more function pointers than before. Tested
on i386 and (with a new host driver) acorn32. Compiled on several other
affected architectures.

cleanup old lpt(4) attachment, and glue ppbus in so that they can coexist:
* lpt device is defined in MI place (dev/ppbus/files.ppbus), dev/ic/lpt.c
is included there too; dev/ic/lpt.c is not included if ppbus is
configured or if there is alternative platform lpt (like for pc532)
* g/c MD lpt definitions and custom puc/upc attachments,
glue moved to conf/files and dev/pci/files.pci respectively; remove
device lpt definition from dev/isa/files.isa
* add ppbus parport attribute, atppc device attachments, adjust plip and lpt
glue

SIGINFO support.
Todo: 32bit compat support (COMPAT_NETBSD32 will not compile right now,
as it won't on other platforms).

Move the bulk of pci_intr_string into a seperate intr_string function. Use
that new function to print the pciide compat interrupt in pciide_machdep.c.
Share pciide_machdep.c between amd64 and i386.

Pass pointers to frames from assembly, do not use the 'frame on stack
as argument passed by value' trick, as gcc 3.3.x makes (valid) assumptions
about the stack that will not be true. Costs 2 instructions per trap/syscall
on i386, 4 per interrupt for MP. One instruction per trap/syscall on amd64,
2 per interrupt for MP. I expect gcc 3.3.1 to make up for this by better
optimization (it'd better..)

While here, make amd64 compile again by using subr_mbr_disk.c

Since everyone uses clock_subr.c (or should, if they don't currently),
list it in conf/files instead of in every port's files.*.

branches: 1.3.2;
ACPI support. Wakeup code still to be done.

Add dummy eisa option to ease sharing with i386.

Rename the x86_64 port to amd64, as this is the actual name used for
the processor family now. x86_64 is kept as the MACHINE_ARCH value,
since it's already widely used (by e.g. the toolchain, etc), and
by other operating systems.