Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Revamp the interrupt code based on the previous commit:
o Introduce XIV, eXternal Interrupt Vector, to differentiate from
the interrupts vectors that are offsets in the IVT (Interrupt
Vector Table). There's a vector for external interrupts, which
are based on the XIVs.

o Keep track of allocated and reserved XIVs so that we can assign
XIVs without hardcoding anything. When XIVs are allocated, an
interrupt handler and a class is specified for the XIV. Classes
are:
1. architecture-defined: XIV 15 is returned when no external
interrupt are pending,
2. platform-defined: SAL reports which XIV is used to wakeup
an AP (typically 0xFF, but it's 0x12 for the Altix 350).
3. inter-processor interrupts: allocated for SMP support and
non-redirectable.
4. device interrupts (i.e. IRQs): allocated when devices are
discovered and are redirectable.

o Rewrite the central interrupt handler to call the per-XIV
interrupt handler and rename it to ia64_handle_intr(). Move
the per-XIV handler implementation to the file where we have
the XIV allocation/reservation. Clock interrupt handling is
moved to clock.c. IPI handling is moved to mp_machdep.c.

o Drop support for the Intel 8259A because it was broken. When
XIV 0 is received, the CPU should initiate an INTA cycle to
obtain the interrupt vector of the 8259-based interrupt. In
these cases the interrupt controller we should be talking to
WRT to masking on signalling EOI is the 8259 and not the I/O
SAPIC. This requires adriver for the Intel 8259A which isn't
available for ia64. Thus stop pretending to support ExtINTs
and instead panic() so that if we come across hardware that
has an Intel 8259A, so have something real to work with.

o With XIVs for IPIs dynamically allocatedi and also based on
priority, define the IPI_* symbols as variables rather than
constants. The variable holds the XIV allocated for the IPI.

o IPI_STOP_HARD delivers a NMI if possible. Otherwise the XIV
assigned to IPI_STOP is delivered.

Export the bus, cpu and itc frequencies under the hw.freq sysctl node.
The frequencies are in MHz (i.e. a value of 1000 represents 1GHz). The
frequencies are rounded to the nearest whole MHz.

While here, rename and re-type bus_frequency, processor_frequency and
itc_frequency to bus_freq, cpu_freq and itc_freq and make them static.
As unsigned integers, the hw.freq.cpu sysctl can more easily be made
generic (across all architectures) making porting easier.

MFC after: 3 days

The "free-lance" timer in the i8254 is only used for the speaker
these days, so de-generalize the acquire_timer/release_timer api
to just deal with speakers.

The new (optional) MD functions are:
timer_spkr_acquire()
timer_spkr_release()
and
timer_spkr_setfreq()

the last of which configures the timer to generate a tone of a given
frequency, in Hz instead of 1/1193182th of seconds.

Drop entirely timer2 on pc98, it is not used anywhere at all.

Move sysbeep() to kern/tty_cons.c and use the timer_spkr*() if
they exist, and do nothing otherwise.

Remove prototypes and empty acquire-/release-timer() and sysbeep()
functions from the non-beeping archs.

This eliminate the need for the speaker driver to know about
i8254frequency at all. In theory this makes the speaker driver MI,
contingent on the timer_spkr_*() functions existing but the driver
does not know this yet and still attaches to the ISA bus.

Syscons is more tricky, in one function, sc_tone(), it knows the hz
and things are just fine.

In the other function, sc_bell() it seems to get the period from
the KDMKTONE ioctl in terms if 1/1193182th second, so we hardcode
the 1193182 and leave it at that. It's probably not important.

Change a few other sysbeep() uses which obviously knew that the
argument was in terms of i8254 frequency, and leave alone those
that look like people thought sysbeep() took frequency in hertz.

This eliminates the knowledge of i8254_freq from all but the actual
clock.c code and the prof_machdep.c on amd64 and i386, where I think
it would be smart to ask for help from the timecounters anyway [TBD].

First part of a little cleanup in the calendar/timezone/RTC handling.

Move relevant variables to <sys/clock.h> and fix #includes as necessary.

Use libkern's much more time- & spamce-efficient BCD routines.

/* -> /*- for copyright notices, minor format tweaks as necessary

Cleanup the clock code. This includes:
o Remove alpha specific timer code (mc146818A) and compiled-out
calibration of said timer.
o Remove i386 inherited timer code (i8253) and related acquire and
release functions.
o Move sysbeep() from clock.c to machdep.c and have it return
ENODEV. Console beeps should be implemented using ACPI or if no
such device is described, using the sound driver.
o Move the sysctls related to adjkerntz, disable_rtc_set and
wall_cmos_clock from machdep.c to clock.c, where the variables
are.
o Don't hardcode a hz value of 1024 in cpu_initclocks() and don't
bother faking a stathz that's 1/8 of that. Keep it simple: hz
defaults to HZ and stathz equals hz. This is also how it's done
for sparc64.
o Keep a per-CPU ITC counter (pc_clock) and adjustment (pc_clockadj)
to calculate ITC skew and corrections. On average, we adjust the
ITC match register once every ~1500 interrupts for a duration of
2 consequtive interruprs. This is to correct the non-deterministic
behaviour of the ITC interrupt (there's a delay between the match
and the raising of the interrupt).
o Add 4 debugging sysctls to monitor clock behaviour. Those are
debug.clock_adjust_edges, debug.clock_adjust_excess,
debug.clock_adjust_lost and debug.clock_adjust_ticks. The first
counts the individual adjustment cycles (when the skew first
crosses the threshold), the second counts the number of times the
adjustment was excessive (any non-zero value is to be considered
a bug), the third counts lost clock interrupts and the last counts
the number of interrupts for which we applied an adjustment
(debug.clock_adjust_ticks / debug.clock_adjust_edges gives the
avarage duration of an individual adjustment -- should be ~2).

While here, remove some nearby (trivial) left-overs from alpha and
other cleanups.

Replace the hardcoding of 255 as the clock interrupt vector with
CLOCK_VECTOR and define it as 254, not 255. Vector 255 is already
in use as the AP wakeup vector on the HP rx2600.

This needs to be made more dynamic. The likelyhood of vector 254
being in use is pretty small, but we already have code to assign
vectors to IPIs (see sal.c) and it's preobably better to have a
centralized "vector manager" that hands out vectors based on
some imput (like priority).

Manually inline handleclock(). There's only a single caller and
handleclock itself is trivial.

While here, replace (itc_frequency+hz/2)/hz with itm_reload for
consistency. There's now a single place where we determine the
ITM reload value.

Gah, spell extern correctly. Do not trust cut/paste via old mozilla
builds.

Declare itc_frequency and itm_reload.

Remove __P.

Reviewd by: peter

Stick a prototype for handleclock() in machine/clock.h and include it
interrupt.c to quiet a warning.

Move DELAY() from <machine/clock.h> to <sys/systm.h>

This is the first snapshot of the FreeBSD/ia64 kernel. This kernel will
not work on any real hardware (or fully work on any simulator). Much more
needs to happen before this is actually functional but its nice to see
the FreeBSD copyright message appear in the ia64 simulator.