Commit Graph

652 Commits

Author SHA1 Message Date
Peter Wemm
1467a651ab Convert apm from a bogus 'count' into a plain option. Clean out some
other cruft from the files.alpha and files.ia64 that were related to this.
2001-01-19 14:09:54 +00:00
John Baldwin
8339bca6db Add in a space that got lost in the previous commit in some debugging code
so that '&' becomes a binary operator and not a unary operator.
2001-01-19 11:43:13 +00:00
Peter Wemm
95bca00f46 EEK! I missed a couple of places with the 24->32 interrupt change. 2001-01-19 10:55:13 +00:00
Peter Wemm
dfb1071f3c Fix a warning (the prototypes probably shouldn't be so over-zealously
#ifdef'ed though)
2001-01-19 09:07:16 +00:00
John Baldwin
10fd583277 Free the intrhand name when free'ing a intrhand.
Submitted by:	bde
2001-01-16 02:17:51 +00:00
Peter Wemm
194b08ffc3 Implement an optimization for INTREN/INTRDIS that bde pointed out last
time I tinkered around here.  Since INTREN is called from the interrupt
critical path now, it should not be too expensive.  In this case, we
look at the bits being changed to decide which 8 bit IO port to write to
rather than unconditionally writing to both.  I could probably have gone
further and only done the write if the bits actually changed, but that
seemed overkill for the usual case in interrupt threads.

[an outb is rather expensive when it has to cross the ISA bus]
2001-01-15 04:18:58 +00:00
Jake Burkholder
ef73ae4b0c Use PCPU_GET, PCPU_PTR and PCPU_SET to access all per-cpu variables
other then curproc.
2001-01-10 04:43:51 +00:00
Jake Burkholder
41ed17bfec Use %fs to access per-cpu variables in uni-processor kernels the same
as multi-processor kernels.  The old way made it difficult for kernel
modules to be portable between uni-processor and multi-processor
kernels.  It is no longer necessary to jump through hoops.

- always load %fs with the private segment on entry to the kernel
- change the type of the self referntial pointer from struct privatespace
  to struct globaldata
- make the globaldata symbol have value 0 in all cases, so the symbols
  in globals.s are always offsets, not aliases for fields in globaldata
- define the globaldata space used for uniprocessor kernels in C, rather
  than assembler
- change the assmebly language accessors to use %fs, add a macro
  PCPU_ADDR(member, reg), which loads the register reg with the address
  of the per-cpu variable member
2001-01-06 17:40:04 +00:00
Jake Burkholder
6d43764a10 Introduce a new potientially cleaner interface for accessing per-cpu
variables from i386 assembly language.  The syntax is PCPU(member)
where member is the capitalized name of the per-cpu variable, without
the gd_ prefix.  Example: movl %eax,PCPU(CURPROC).  The capitalization
is due to using the offsets generated by genassym rather than the symbols
provided by linking with globals.o.  asmacros.h is the wrong place for
this but it seemed as good a place as any for now.  The old implementation
in asnames.h has not been removed because it is still used to de-mangle
the symbols used by the C variables for the UP case.
2000-12-13 09:23:53 +00:00
David Malone
7cc0979fd6 Convert more malloc+bzero to malloc+M_ZERO.
Submitted by:	josh@zipperup.org
Submitted by:	Robert Drehmel <robd@gmx.net>
2000-12-08 21:51:06 +00:00
Peter Wemm
5ee171d264 Cleanup some leftover lint from the old interrupt system.
Also, while here, run up to 32 interrupt sources on APIC systems.
Normalize INTREN/INTRDIS so they are the same on both UP and SMP systems
rather than sometimes a macro, and sometimes a function.

Reviewed by:  jhb, jakeb
2000-12-04 21:15:14 +00:00
Mark Murray
4a3a2f0704 Namespace cleanup. Remove some #includes in favour of an explicit
declaration.

Asked for by:	bde
2000-12-02 17:59:41 +00:00
Jake Burkholder
21ad98bca8 Change doreti to take a trapframe instead of an intrframe.
Remove associated pushes of dummy units to convert frame.

Reviewed by:	jhb
2000-12-01 02:09:45 +00:00
John Baldwin
7c06c69188 Assert that Giant is not owned during the main loop of ithd_loop(). 2000-11-15 22:03:26 +00:00
Poul-Henning Kamp
54b1161b73 Revert two experimental changes which escaped from my devel machine. 2000-10-28 06:55:12 +00:00
John Baldwin
7c0cb49a64 Fix a couple of whitespace nits. 2000-10-27 21:45:50 +00:00
Poul-Henning Kamp
46aa3347cb Convert all users of fldoff() to offsetof(). fldoff() is bad
because it only takes a struct tag which makes it impossible to
use unions, typedefs etc.

Define __offsetof() in <machine/ansi.h>

Define offsetof() in terms of __offsetof() in <stddef.h> and <sys/types.h>

Remove myriad of local offsetof() definitions.

Remove includes of <stddef.h> in kernel code.

NB: Kernelcode should *never* include from /usr/include !

Make <sys/queue.h> include <machine/ansi.h> to avoid polluting the API.

Deprecate <struct.h> with a warning.  The warning turns into an error on
01-12-2000 and the file gets removed entirely on 01-01-2001.

Paritials reviews by:   various.
Significant brucifications by:  bde
2000-10-27 11:45:49 +00:00
Paul Saab
fbdfe15620 Fast interrupts have no associated process, therefore do not try
and schedule it.  This fixes booting machines with broken MP tables.
2000-10-25 10:40:20 +00:00
John Baldwin
8088699f79 - Overhaul the software interrupt code to use interrupt threads for each
type of software interrupt.  Roughly, what used to be a bit in spending
  now maps to a swi thread.  Each thread can have multiple handlers, just
  like a hardware interrupt thread.
- Instead of using a bitmask of pending interrupts, we schedule the specific
  software interrupt thread to run, so spending, NSWI, and the shandlers
  array are no longer needed.  We can now have an arbitrary number of
  software interrupt threads.  When you register a software interrupt
  thread via sinthand_add(), you get back a struct intrhand that you pass
  to sched_swi() when you wish to schedule your swi thread to run.
- Convert the name of 'struct intrec' to 'struct intrhand' as it is a bit
  more intuitive.  Also, prefix all the members of struct intrhand with
  'ih_'.
- Make swi_net() a MI function since there is now no point in it being
  MD.

Submitted by:	cp
2000-10-25 05:19:40 +00:00
John Baldwin
35e0e5b311 Catch up to moving headers:
- machine/ipl.h -> sys/ipl.h
- machine/mutex.h -> sys/mutex.h
2000-10-20 07:58:15 +00:00
John Baldwin
d1182da2cf Actually harvest interrupt threads when the last handler is removed from a
thread.
2000-10-20 07:46:12 +00:00
John Baldwin
02660e29a8 - machine/mutex.h -> sys/mutex.h
- machine/ipl.h -> sys/ipl.h
- Use MUTEX_DECLARE() for clock_lock
2000-10-20 07:31:00 +00:00
KATO Takenori
1ae7243298 Convert the type of bus_space_handle_t of pc98 from structure into
pointer to structure.

Reviewed by:	nyan
2000-10-20 02:42:06 +00:00
John Baldwin
6c56727456 - Change fast interrupts on x86 to push a full interrupt frame and to
return through doreti to handle ast's.  This is necessary for the
  clock interrupts to work properly.
- Change the clock interrupts on the x86 to be fast instead of threaded.
  This is needed because both hardclock() and statclock() need to run in
  the context of the current process, not in a separate thread context.
- Kill the prevproc hack as it is no longer needed.
- We really need Giant when we call psignal(), but we don't want to block
  during the clock interrupt.  Instead, use two p_flag's in the proc struct
  to mark the current process as having a pending SIGVTALRM or a SIGPROF
  and let them be delivered during ast() when hardclock() has finished
  running.
- Remove CLKF_BASEPRI, which was #ifdef'd out on the x86 anyways.  It was
  broken on the x86 if it was turned on since cpl is gone.  It's only use
  was to bogusly run softclock() directly during hardclock() rather than
  scheduling an SWI.
- Remove the COM_LOCK simplelock and replace it with a clock_lock spin
  mutex.  Since the spin mutex already handles disabling/restoring
  interrupts appropriately, this also lets us axe all the *_intr() fu.
- Back out the hacks in the APIC_IO x86 cpu_initclocks() code to use
  temporary fast interrupts for the APIC trial.
- Add two new process flags P_ALRMPEND and P_PROFPEND to mark the pending
  signals in hardclock() that are to be delivered in ast().

Submitted by:	jakeb (making statclock safe in a fast interrupt)
Submitted by:	cp (concept of delaying signals until ast())
2000-10-06 02:20:21 +00:00
John Baldwin
1931cf940a - Heavyweight interrupt threads on the alpha for device I/O interrupts.
- Make softinterrupts (SWI's) almost completely MI, and divorce them
  completely from the x86 hardware interrupt code.
  - The ihandlers array is now gone.  Instead, there is a MI shandlers array
    that just contains SWI handlers.
  - Most of the former machine/ipl.h files have moved to a new sys/ipl.h.
- Stub out all the spl*() functions on all architectures.

Submitted by:	dfr
2000-10-05 23:09:57 +00:00
John Baldwin
7ab37af1ed - Add a new process flag P_NOLOAD that marks a process that should be
ignored during load average calcuations.
- Set this flag for the idle processes and the softinterrupt process.
2000-09-15 22:00:23 +00:00
John Baldwin
518afc0f11 Check to see if we actually have an interrupt descriptor and an interrupt
thread for each interrupt that comes in.  If we don't, log the event and
return immediately for a hardware interrupt.  For a softinterrupt, panic
instead.

Submitted by:	ben
2000-09-15 00:27:57 +00:00
John Baldwin
9a94c9c5c3 - Remove the inthand2_t type and use the equivalent driver_intr_t type from
newbus for referencing device interrupt handlers.
- Move the 'struct intrec' type which describes interrupt sources into
  sys/interrupt.h instead of making it just be a x86 structure.
- Don't create 'ithd' and 'intrec' typedefs, instead, just use 'struct ithd'
  and 'struct intrec'
- Move the code to translate new-bus interrupt flags into an interrupt thread
  priority out of the x86 nexus code and into a MI ithread_priority()
  function in sys/kern/kern_intr.c.
- Remove now-uneeded x86-specific headers from sys/dev/ata/ata-all.c and
  sys/pci/pci_compat.c.
2000-09-13 18:33:25 +00:00
Bruce Evans
d511196c02 Don't panic for delivery of a multiplexed SWI. Most SWI handlers
don't take an arg, but swi_generic() is special in order to avoid one
whole conditional branch in the old SWI dispatch code.  The new SWI
dispatch code passed it a garbage arg.  Bypass swi_generic() and call
swi_dispatcher() directly, like the corresponding alpha code has always
done.

The panic was rare because because it only occurred if more than one
of the {sio,cy,rc} drivers was configured and one was active, and the
cy driver doesn't even compile.
2000-09-12 16:02:43 +00:00
Yoshihiro Takahashi
f69dfaede1 Don't assume that address of I/O address table increase (PC-98 only).
Pointed out by:	Tomokazu HARADA <tkhara@osk4.3web.ne.jp>
2000-09-07 14:43:00 +00:00
Jason Evans
0384fff8c5 Major update to the way synchronization is done in the kernel. Highlights
include:

* Mutual exclusion is used instead of spl*().  See mutex(9).  (Note: The
  alpha port is still in transition and currently uses both.)

* Per-CPU idle processes.

* Interrupts are run in their own separate kernel threads and can be
  preempted (i386 only).

Partially contributed by:	BSDi (BSD/OS)
Submissions by (at least):	cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
Paul Saab
c206a8609e Change the behavior of isa_nmi to log an error message instead of
panicing and return a status so that we can decide whether to drop
into DDB or panic.  If the status from isa_nmi is true, panic the
kernel based on machdep.panic_on_nmi, otherwise if DDB is
enabled, drop to DDB based on machdep.ddb_on_nmi.

Reviewed by:	peter, phk
2000-08-06 14:17:21 +00:00
Poul-Henning Kamp
0825a8a33f Allow use of TSC even if APM is compiled in but disabled. 2000-07-30 21:05:22 +00:00
Poul-Henning Kamp
77978ab8bc Previous commit changing SYSCTL_HANDLER_ARGS violated KNF.
Pointed out by:	bde
2000-07-04 11:25:35 +00:00
Poul-Henning Kamp
82d9ae4e32 Style police catches up with rev 1.26 of src/sys/sys/sysctl.h:
Sanitize SYSCTL_HANDLER_ARGS so that simplistic tools can grog our
sources:

        -sysctl_vm_zone SYSCTL_HANDLER_ARGS
        +sysctl_vm_zone (SYSCTL_HANDLER_ARGS)
2000-07-03 09:35:31 +00:00
Steve Passe
80940373ed Fixed atpic_attach() for the SMP (specifically APIC_IO) case.
Approved by:	msmith@freebsd.org
2000-06-24 23:55:38 +00:00
Mike Smith
bb9c06c1ce Make the PnP 'slopsucker' quiet in the !bootverbose case - the real NPX
probe happens much earlier, and may come to very different conclusions
about the system's NPX setup.
2000-06-23 08:19:50 +00:00
Mike Smith
2a50a6d730 Add PnP probe methods to some common AT hardware drivers. In each case,
the PnP probe is merely a stub as we make assumptions about some of this
hardware before we have probed it.

Since these devices (with the exception of the speaker) are 'standard',
suppress output in the !bootverbose case to clean up the probe messages
somewhat.
2000-06-23 07:44:33 +00:00
Bruce Evans
6b4a3ce242 Pack the SWI bits to save some time and space. 2000-05-31 16:36:20 +00:00
Bruce Evans
5f582114dd Add SWI_TQ_MASK to all interrupt masks except SWI_CLOCK_MASK. Use a
new macro SWI_LOW_MASK to give the mask for low priority SWIs instead
of hard-coding this mask as SWI_CLOCK_MASK.

Reviewed by:	dfr
2000-05-31 13:32:28 +00:00
Doug Rabson
3e8965ac09 Add SWI_TQ_MASK to imask definition. 2000-05-29 19:40:42 +00:00
Peter Wemm
e60463deed Redo the isa compat driver shim so that each driver is self contained
and does not require that evil list of drivers in isa_compat.h.
It uses the same strategy that pci drivers use, namely a
COMPAT_ISA_DRIVER() macro that creates the glue on the fly.
Theoretically old-style isa drivers should be preloadable now.
2000-05-28 13:30:44 +00:00
David E. O'Brien
fc81cf82e9 1. `movl' is for use with 32-bit operands. Do NOT use it with 16-bit
operands.  `movw' could be used, but instead let the assembler decide
   the right instruction to use.
2. AT&T asm syntax requires a leading '*' in front of the operand for
   indirect calls and jumps.
2000-05-10 01:24:23 +00:00
Garrett Wollman
54f1d0cefe Add a little do-nothing ``slopsucker'' device which gives a home
to PNP0c04 (legacy ISA coprocessor support).  Tourist info.
2000-05-04 23:57:32 +00:00
Peter Wemm
621372ff84 Mark two functions as private. 2000-04-29 07:48:37 +00:00
KATO Takenori
91cb959ddb Added indirect pio into the bus space stuff for the NEC PC-98. bus.h
includes one of bus_at386.h and bus_pc98.h. Becuase only bus_pc98.h
supports indirect pio and bus_at386.h is identical to old bus.h, there
is no functional change in PC-AT's kernels.  That is, it cannot cause
performance loss.

Submitted by:	nyan
Reviewed by:	imp
bde and luoqi provided useful comments for earlier version.
2000-03-29 03:15:22 +00:00
Poul-Henning Kamp
91266b96c4 Isolate the Timecounter internals in their own two files.
Make the public interface more systematically named.

Remove the alternate method, it doesn't do any good, only ruins performance.

Add counters to profile the usage of the 8 access functions.

Apply the beer-ware to my code.

The weird +/- counts are caused by two repocopies behind the scenes:
	kern/kern_clock.c -> kern/kern_tc.c
	sys/time.h -> sys/timetc.h
(thanks peter!)
2000-03-20 14:09:06 +00:00
Peter Wemm
80060e8897 Connect the ISA and PCI compatability shims to an option. In this case
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.
2000-03-19 13:07:12 +00:00
Poul-Henning Kamp
d8b47cbb70 Stop isadma from abusing the B_READ, B_RAW and B_WRITE flags.
Define ISADMA_{READ,WRITE,RAW} macros with the same numeric
values as the B_{READ,WRITE,RAW} and use them instead throughout.
2000-03-13 10:19:32 +00:00
Peter Wemm
690f85de65 Remove a bunch of unused (NO-OP) #if NFOO > 0 type includes and some
#include "foo.h" headers.
2000-01-29 16:17:36 +00:00
Doug Rabson
a43a8fd704 Use device_printf() instead of device_print_prettyname(). 2000-01-25 21:39:20 +00:00
Tor Egge
82916a1126 ISA device drivers use the ISA source interrupt number in locations where
the low level interrupt handler number should be used.  Change
setup_apic_irq_mapping() to allocate low level interrupt handler X (Xintr${X})
for any ISA interrupt X mentioned in the MP table.

Remove an assumption in the driver for the system clock (clock.c) that
interrupts mentioned in the MP table as delivered to IOAPIC #0 intpin Y
is handled by low level interrupt handler Y (Xintr${Y}) but don't assume
that low level interrupt handler 0 (Xintr0) is used.

Don't allocate two low level interrupt handlers for the system clock.
Reviewed by:	NOKUBI Hirotaka <hnokubi@yyy.or.jp>
2000-01-04 22:24:59 +00:00
Peter Wemm
664a31e496 Change #ifdef KERNEL to #ifdef _KERNEL in the public headers. "KERNEL"
is an application space macro and the applications are supposed to be free
to use it as they please (but cannot).  This is consistant with the other
BSD's who made this change quite some time ago.  More commits to come.
1999-12-29 04:46:21 +00:00
Bruce Evans
9bcde22f7a Don't include <isa/isavar.h> or compile code depending on it when isa
is not configured.  Including <isa/isavar.h> when it is not used is
harmful as well as bogus, since it includes "isa_if.h" which is not
generated when isa is not configured.
1999-12-26 16:21:19 +00:00
Bruce Evans
ffd344ddbb Replaced the INTRMASK and INTRUNMASK macros by "|" and "&~" operations.
Some interface botches went away, leaving the macros unused outside of
the implementation of interrupt masking, and it was silly for the
implementation to use the macros in only one place each.
1999-12-26 12:43:47 +00:00
Bruce Evans
0f19e631e2 Fixed races accessing the RTC. The races apparently caused
apm_default_resume() to sometimes set a very wrong time.
(1) Accesses to the RTC index and data registers were not atomic enough.
    Interrupts were not masked.  This was only good enough until an
    interrupt handler (rtcintr()) started accessing the RTC in FreeBSD-2.0.
(2) Access to the block of time registers in inittodr() was not atomic
    enough.  inittodr() has 244us to read the time registers.  Interrupts
    were not masked.  This was only good enough until something (apm)
    started calling inittodr() after boot time in FreeBSD-2.0.
The fix for (2) also makes the timecounter update more atomic, although
this is currently unimportant due to the low resolution of the RTC.

Problem reported by:	mckay
1999-12-25 15:30:31 +00:00
Eivind Eklund
4c8d1f1d99 Use the correct return value for MCA NMIs.
Reviewed by:	mdodd
1999-12-21 18:13:02 +00:00
Peter Wemm
ec6e462d78 Remove references to register_intr() etc in comments. 1999-12-20 15:11:31 +00:00
Peter Wemm
c13a71596b Zap the old isa_device specific register_intr() and unregister_intr()
emulations.  Thankfully, nothing is left in the tree that uses them.
1999-12-20 15:01:23 +00:00
Mitsuru IWASAKI
29803c2003 i8254_restore is called from apm_default_resume() to reload
the countdown register.
this should not be necessary but there are broken laptops that
do not restore the countdown register on resume.
when it happnes, it messes up the hardclock interval and system clock,
which leads to the infamous "calcru: negative time" problem.

Submitted by:	kjc, iwasaki
Reviewed by:	Steve O'Hara-Smith <steveo@eircom.net> and committers.
Obtained from:	PAO3
1999-10-30 14:56:01 +00:00
Doug Rabson
25afb89b1c * Add struct resource_list* argument to resource_list_alloc and
resource_list_release. This removes the dependancy on the
  layout of ivars.

* Move set_resource, get_resource and delete_resource from
  isa_if.m to bus_if.m.

* Simplify driver code by providing wrappers to those methods:

     bus_set_resource(dev, type, rid, start, count);
     bus_get_resource(dev, type, rid, startp, countp);
     bus_get_resource_start(dev, type, rid);
     bus_get_resource_count(dev, type, rid);
     bus_delete_resource(dev, type, rid);

* Delete isa_get_rsrc and use bus_get_resource_start instead.

* Fix a stupid typo in isa_alloc_resource reported by Takahashi
  Yoshihiro <nyan@FreeBSD.org>.

* Print a diagnostic message if we can't assign resources to a PnP
  device.

* Change device_print_prettyname() so that it doesn't print
  "(no driver assigned)-1" for anonymous devices.
1999-10-12 21:35:51 +00:00
Peter Wemm
3b8f07bbc3 Trim some unused #includes
Submitted by:	phk
1999-10-11 15:00:09 +00:00
Poul-Henning Kamp
163473ebd5 Print out flags value 1999-09-21 10:51:47 +00:00
Matthew N. Dodd
7612e4c122 This adds the i386 specific support for systems with a MicroChannel
Architecture bus.

Reviewed by: msmith
1999-09-03 02:04:28 +00:00
Peter Wemm
1be9d26e4a Eliminate some magic numbers. 1999-09-01 06:34:24 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Peter Wemm
da4113b31f Add an identify method to allow npx to arrange itself to be attached to
the nexus without explicit code in the nexus to do so.
1999-08-22 19:52:51 +00:00
Poul-Henning Kamp
ce9edcf5b5 Merge the cons.c and cons.h to the best of my ability. alpha may or
may not compile, I can't test it.
1999-08-09 10:35:05 +00:00
Brian Feldman
8799702cbc Remove XXX from the headers (broke the build, I'm betting.) 1999-07-29 01:20:47 +00:00
Mike Smith
e33bfde398 We're called too early to have any idea whether APM is going to be
active or not.  The only sane thing we can do here is assume that if
APM is supported it might be active at some point, and bail.

In reality, even this isn't good enough; regardless of whether we support
APM or not, the system may well futz with the CPU's clock speed and throw
the TSC off.  We need to stop using it for timekeeping except under
controlled circumstances.  Curse the lack of a dependable high-resolution
timer.
1999-07-28 20:22:30 +00:00
Martin Cracauer
784648c675 Various formatting fixes on my FPE trapcode commit.
Submitted by:	BDE
1999-07-26 05:47:31 +00:00
Martin Cracauer
a7674320e9 On FPU exceptions, pass a useful error code (one of the FPE_...
macros) to the signal handler, for old-style BSD signal handlers as
the second (int) argument, for SA_SIGINFO signal handlers as
siginfo_t->si_code. This is source-compatible with Solaris, except
that we have no <siginfo.h> (which isn't even mentioned in POSIX
1003.1b).

An rather complete example program is at
  http://www3.cons.org/cracauer/freebsd-signal.c
This will be added to the regression tests in src/.

This commit also adds code to disable the (hardware) FPU from
userconfig, so that you can use a software FP emulator on a machine
that has hardware floating point. See LINT.
1999-07-25 13:16:09 +00:00
Mike Smith
91fe3dc1e1 Implement an all-CPU shootdown-style rendezvous facility. This allows
the caller to specify a function to be guarded between an entry and exit
barrier, as well as pre- and post-barrier functions.

The primary use for this function is synchronised update of per-cpu private
data.  The implementation is almost (but not quite) MI; with a better
mechanism for masking per-CPU interrupts it could probably be hoisted.

Reviewed by:	peter (partially)
1999-07-20 06:52:35 +00:00
Bruce Evans
e9ecccf8cb Updated acquire_timer2()'s state machine to work when the i8254 is
being used for timecounting.  Fixed a race or two in it.  Undisabled
it.

PR:		10455
1999-07-18 18:32:42 +00:00
Bruce Evans
ab64b6dc3c Don't let the machdep.tsc_freq sysctl proceed if the TSC is present
but broken, since tsc_timecounter is not initialised in that case,
and updating an uninitialised timecounter is fatal.

Fixed style bugs in the machdep.i8254_freq and machdep.tsc_freq
sysctls.

Reviewed by:	phk
1999-07-18 15:19:29 +00:00
Bruce Evans
eec2e836e9 Go back to the old (icu.s rev.1.7 1993) way of keeping the AST-pending
bit separate from ipending, since this is simpler and/or necessary for
SMP and may even be better for UP.

Reviewed by:	alc, luoqi, tegge
1999-07-10 15:28:01 +00:00
Bruce Evans
c618090a83 Fixed a longstanding scheduling bug. ASTs and softclock interrupts were
not masked during handling of shared PCI interrupts.  This resulted in
ASTs sometimes being discarded and softclock interrupts sometimes being
handled prematurely (sometimes = quite often on systems with shared PCI
interrupts, never on other systems).

Debugged by:	gibbs and other people at plutotech.com
PR:		6944, maybe 12381
1999-07-10 14:54:19 +00:00
Peter Wemm
e66b7bac41 Shut up gcc. 1999-06-27 09:08:48 +00:00
Brian Feldman
9840e7cb5a This commit gives support for the Rise mP6 CPU. It has two changes:
1. Rise is recognized in identdcpu.c.
	2. The TSC is not written to. A workaround for the CPU bug is being
	   applied to clock.c (the bug being that the mP6 has TSC enabled
	   in its CPUID-capabilities, but it only supports reading it. If we
	   try to write to it (MSR 16), a GPF occurs.) The new behavior is that
	   FreeBSD will _not_ zero the TSC. Instead, we do a bit of 64-bit
	   arithmetic.

Reviewed by:	msmith
Obtained from:	unfurl & msmith
1999-06-24 03:48:25 +00:00
Peter Wemm
e6eca02874 remove references to isa_device, it's no longer associated with interrupts. 1999-06-03 20:41:00 +00:00
Doug Rabson
3bfc7e5928 Remove fd driver from its old home and change files which include rtc.h
to account for its new location.
1999-05-31 18:36:14 +00:00
Doug Rabson
8b05278ca1 Allow up to 8 ports, 4 memory regions and two irqs and drqs. 1999-05-30 11:05:39 +00:00
Poul-Henning Kamp
6deb5a62cc Stop the TSC from being used as timecounter on K5/step0 machines. 1999-05-29 06:57:55 +00:00
Bruce Evans
b50641ef9c Fixed glitches (jumps) of about 1/HZ seconds for the i8254 timecounter.
The old version only worked right when the time was read strictly
more often than every 1/HZ seconds, but we only guarantee reading
it every (1/HZ + epsilon) seconds.  Part of rev.1.126-1.127 attempted
to fix this but didn't succeed.  Detect counter rollover using the
heuristic from the old version of microtime() with additional
complications for supporting calls from fast interrupt handlers.
This works provided i8254 interrupts are not delayed by more than
1/(2*HZ) seconds.

This needs more comments, and cleanups for the SMP case, and more
testing of the SMP case before it is merged into RELENG_3.

Tested by:		jhay
1999-05-28 14:08:59 +00:00
Doug Rabson
a3be63b3ce * Factor out the common code between the isa bus drivers for i386 and alpha.
* Re-work the resource allocation code to use helper functions in subr_bus.c.
* Add simple isa interface for manipulating the resource ranges which can be
  allocated and remove the code from isa_write_ivar() which was previously
  used for this purpose.
1999-05-22 15:18:28 +00:00
Peter Wemm
2b5be3fad4 Recover from removing the last (unshared) interrupt handler.
PR:		11806
Submitted by:	Assar Westerlund <assar@sics.se>
1999-05-22 09:39:31 +00:00
Peter Wemm
2f2ffb8d2c Don't hardcode IRQ 13 for NPX. It's as good as hardwired in the hardware
though, on systems (386 mostly) that still have a seperate fpu, but it
might be possible to find systems where the FPU coprocessor is wired to
a different IRQ pin.
1999-05-15 17:58:58 +00:00
Doug Rabson
6c2e3dde8c * Define a new static method DEVICE_IDENTIFY which is called to add device
instances to a parent bus.
* Define a new method BUS_ADD_CHILD which can be called from DEVICE_IDENTIFY
  to add new instances.
* Add a generic implementation of DEVICE_PROBE which calls DEVICE_IDENTIFY
  for each driver attached to the parent's devclass.
* Move the hint-based isa probe from the isa driver to a new isahint driver
  which can be shared between i386 and alpha.
1999-05-14 11:22:47 +00:00
Luoqi Chen
cd121c9cae Yet another place I missed when increasing trapframe size, which causes problem
to SIGFPE handling.

Reviewed by:	Bruce Evans	<bde@zeta.org.au>
1999-05-11 16:29:21 +00:00
Peter Wemm
45d84a2db3 Clean out some unused leftovers from before the split from the old isa.c. 1999-05-09 23:56:00 +00:00
Peter Wemm
3bab4ac5a1 For what it's worth, idelayed is declared as a volatile in the headers,
and even though it's not used in this file make it a volatile here too.
1999-05-09 23:32:29 +00:00
Doug Rabson
566643e39e Move the declaration of the interrupt type from the driver structure
to the BUS_SETUP_INTR call.
1999-05-08 21:59:43 +00:00
Peter Wemm
14d3b6b80c GC some #if 0 junk 1999-05-08 21:28:39 +00:00
Peter Wemm
1a738e4be7 Look up the sensitive flag better, allowing interoperation between old and
new isa drivers with sensitive flags.  If the resource_find() code
is meant to "find" the wildcard sensitive flag for a driver even though
a unit is supplied, this can be simplified.
1999-05-08 18:15:49 +00:00
Peter Wemm
df5c783c68 Fix unused variable "flags". (only used if #ifdef I586_CPU) 1999-05-08 18:14:09 +00:00
Peter Wemm
97bf178703 I'm not sure why the #ifdef SMP became #if 1 (this overrode the npx probe
and always succeeded as is required on SMP).  Anyway, reverting this
still compiles and appears ok.
1999-05-06 12:47:21 +00:00
Bruce Evans
ea2b3e3d1b Fixed profiling of elf kernels. Made high resolution profiling compile
for elf kernels (it is broken for all kernels due to lack of egcs support).

Renaming of many assembler labels is avoided by declaring by declaring
the labels that need to be visible to gprof as having type "function"
and depending on the elf version of gprof being zealous about discarding
the others.  A few type declarations are still missing, mainly for SMP.

PR:		9413
Submitted by:	Assar Westerlund <assar@sics.se> (initial parts)
1999-05-06 09:44:57 +00:00
Doug Rabson
6887e80a0f Use unit, not device_id as an argument to an old-style ISA interrupt
handler. This fixes pnp interrupts and would have fixed pccard interrupts
but a workaround has been applied there.

This the sound driver problems which people have reported with new-bus.
1999-05-04 21:18:20 +00:00
Luoqi Chen
5206bca10a Enable vmspace sharing on SMP. Major changes are,
- %fs register is added to trapframe and saved/restored upon kernel entry/exit.
- Per-cpu pages are no longer mapped at the same virtual address.
- Each cpu now has a separate gdt selector table. A new segment selector
  is added to point to per-cpu pages, per-cpu global variables are now
  accessed through this new selector (%fs). The selectors in gdt table are
  rearranged for cache line optimization.
- fask_vfork is now on as default for both UP and SMP.
- Some aio code cleanup.

Reviewed by:	Alan Cox	<alc@cs.rice.edu>
		John Dyson	<dyson@iquest.net>
		Julian Elischer	<julian@whistel.com>
		Bruce Evans	<bde@zeta.org.au>
		David Greenman	<dg@root.com>
1999-04-28 01:04:33 +00:00
Poul-Henning Kamp
0bb2226a4d Make the machdep.i8254_freq and machdep.tsc_freq sysctls modify the
timecounter as well

Asked for by:	bde, jhay
1999-04-25 09:00:00 +00:00
KATO Takenori
424af31b45 Changed the type of id_port from short into int to avoid wrong
conversion from short to unsigned long which is an argument of
bus_alloc_resource.  Since the value -1 is used to indicate no port
reousece, id_port need to be signed (suggested by Doug Rabson and
Peter Wemm.)
1999-04-24 18:24:43 +00:00
Peter Wemm
d70a04d62d Don't clear the hints on release, just the resource containers. 1999-04-24 06:47:24 +00:00
Peter Wemm
525a3d26e7 Make the register_intr() glue actually have a chance of working... 1999-04-23 21:01:19 +00:00
Peter Wemm
8528f91719 oops, SMP was missing includes for a typedef. 1999-04-21 07:41:40 +00:00
Peter Wemm
54a8c69347 Stage 1 of a cleanup of the i386 interrupt registration mechanism.
Interrupts under the new scheme are managed by the i386 nexus with the
awareness of the resource manager.  There is further room for optimizing
the interfaces still.  All the users of register_intr()/intr_create()
should be gone, with the exception of pcic and i386/isa/clock.c.
1999-04-21 07:26:30 +00:00
Peter Wemm
c2c75d780e As a temporary anti-foot-shooting measure, don't let the user attach
the atkbd device to isa, as was in the old (and 3.x) GENERIC config.
1999-04-16 23:39:15 +00:00
Peter Wemm
6182fdbda8 Bring the 'new-bus' to the i386. This extensively changes the way the
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
1999-04-16 21:22:55 +00:00
Bruce Evans
6a9df7a421 Generate intrnames[] dynamically. This should be new-bus friendly.
Old version reviewed by: se
1999-04-14 14:26:36 +00:00
Peter Wemm
b4718cedf6 Move initialization of SWI's in the tty|net|bio masks from isa.c into
the static initializers in ipl.s.
1999-04-11 15:51:15 +00:00
Dmitrij Tejblum
a4ca0596ca Ifdef declaration of a conditionally defined function "timezero". 1999-03-28 23:28:18 +00:00
Bruce Evans
2a32c15f45 Unspammed includes in <machine/cpufunc.h> in the !SMP case. Partially
unspammed them in the SMP case.
1999-01-08 19:17:49 +00:00
Bruce Evans
68ba369606 Moved declarations related to copying and zeroing to the right place. 1999-01-08 16:29:59 +00:00
Kazutaka YOKOTA
2d15a1badc Move IO_PSMSIZE from kbdio.h to isa.h. I thought I did this a long time
ago...

While I am here, correct the values for IO_MDASIZE and IO_CGASIZE; they
should be 12 rather than 16.
1999-01-06 05:40:01 +00:00
Bruce Evans
407e5f394f Moved the declaration of another non-SMP variable into the non-SMP section. 1998-12-14 19:16:17 +00:00
Stephen McKay
2619394c7c Fix tabs that should have been spaces. Some were in kernel error messages. 1998-12-14 13:30:29 +00:00
Archie Cobbs
f1d19042b0 The "easy" fixes for compiling the kernel -Wunused: remove unreferenced static
and local variables, goto labels, and functions declared but not defined.
1998-12-07 21:58:50 +00:00
Archie Cobbs
2127f26023 Examine all occurrences of sprintf(), strcat(), and str[n]cpy()
for possible buffer overflow problems. Replaced most sprintf()'s
with snprintf(); for others cases, added terminating NUL bytes where
appropriate, replaced constants like "16" with sizeof(), etc.

These changes include several bug fixes, but most changes are for
maintainability's sake. Any instance where it wasn't "immediately
obvious" that a buffer overflow could not occur was made safer.

Reviewed by:	Bruce Evans <bde@zeta.org.au>
Reviewed by:	Matthew Dillon <dillon@apollo.backplane.com>
Reviewed by:	Mike Spengler <mks@networkcs.com>
1998-12-04 22:54:57 +00:00
Poul-Henning Kamp
5986967ee2 don't print '?' for ioaddr the device may legitimately not have an
ioaddr.
1998-11-29 15:42:40 +00:00
Poul-Henning Kamp
d259be02bc Update timecounters to new interface. 1998-10-23 10:46:20 +00:00
Bruce Evans
fe310de802 Initialize isa_devtab entries for interrupt handlers in individual
device drivers, not in ioconf.c.  Use a different hack in isa_device.h
so that a new config(8) is not required yet.

pc98 parts approved by: kato
1998-10-22 05:58:45 +00:00
David Greenman
6cde7a165f Fixed two potentially serious classes of bugs:
1) The vnode pager wasn't properly tracking the file size due to
   "size" being page rounded in some cases and not in others.
   This sometimes resulted in corrupted files. First noticed by
   Terry Lambert.
   Fixed by changing the "size" pager_alloc parameter to be a 64bit
   byte value (as opposed to a 32bit page index) and changing the
   pagers and their callers to deal with this properly.
2) Fixed a bogus type cast in round_page() and trunc_page() that
   caused some 64bit offsets and sizes to be scrambled. Removing
   the cast required adding casts at a few dozen callers.
   There may be problems with other bogus casts in close-by
   macros. A quick check seemed to indicate that those were okay,
   however.
1998-10-13 08:24:45 +00:00
Bruce Evans
a4e195e166 Don't print conflict messages in haveseen_isadev() if CC_QUIET is
specified.  This makes haveseen_isadev() useful for searching for a
free resource.  This increases the bitrot in the pci RESOURCE_CHECK
code.

Fixed the pre-attach conflict message.  The flag for distinguishing
pre-attach conflict checks from pre-probe ones was never set.
1998-10-12 13:12:45 +00:00
Bruce Evans
6ed49410a5 Attempt to work around a bug in the previous commit related to
non-reentrancy of SMP clock locking.  Depend on the giant lock
protecting clkintr().
1998-09-20 19:56:28 +00:00
Bruce Evans
a6796db6ce Ensure that the i8254 timecounter doesn't go backards. It sometimes
went backwards when interrupts were masked for more than one i8254
interrupt period.  It sometimes went backwards when the i8254 counter
was reprogrammed.  Neither of these should happen in normal operation.

Update the i8254 timecounter support variables atomically.  Calling
timecounter functions from fast interrupt handlers may actually work
in all cases now.
1998-09-20 03:47:54 +00:00
Tor Egge
572d053e17 Maintain a mapping from irq number to (ioapic number, int pin) tuple,
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.
1998-09-06 22:41:42 +00:00
Bruce Evans
92971f1fd7 Register tty software interrupt handlers at run time using register_swi()
instead of at compile time using ifdefs.

Use _swi_null instead of dummycamisr.  CAM and dpt should call
register_swi() instead of hacking on ihandlers[] directly.
1998-08-11 17:01:32 +00:00
Bruce Evans
18c5a6c435 Implemented dynamic registration of software interrupt handlers. Not
used yet.

Use dummy SWI handlers to avoid some checks for null pointers.
1998-08-11 15:08:13 +00:00
Bruce Evans
f2bd332e7c Stop physical DMA for the non-auto case in isa_dmadone(). This fixes a
small part of a bug suite beginning in the SLICE probes but mostly in the
floppy driver.  This is a quick fix: the auto case shouldn't be special;
DMA should also be stopped in isa_dma_release(); isa_dmastop() probably
shouldn't exist; common DMA registers should not be accessed without
locking.
1998-07-19 04:22:55 +00:00
Bruce Evans
be160d60ab Removed unused includes. 1998-06-21 18:02:50 +00:00
Bruce Evans
5a2ae61fec Converted isa_strayintr() to take a `void *' arg. 1998-06-18 16:08:46 +00:00
Bruce Evans
9a2daf9190 Changed the type of an isa/general interrupt handler to take a
`void *' arg.  Fixed or hid most of the resulting type mismatches.
Handlers can now be updated locally (except for reworking their
global declarations in isa_device.h).
1998-06-18 15:32:09 +00:00
Poul-Henning Kamp
a58f0f8e66 Add a tc_ prefix to struct timecounter members.
Urged by:	bde
1998-06-09 13:10:54 +00:00
Poul-Henning Kamp
48115288df Add a member function more to the timecounters, this one is for use
with latch based PPS implementations.  The client that uses it will
be committed after more testing.
1998-06-07 20:36:55 +00:00
Poul-Henning Kamp
dbb3475507 Add a "this" style argument and a "void *private" so timecounters can
figure out which instance to wount with.
1998-06-07 08:40:53 +00:00
Bruce Evans
cd55b8f46c Converted the ICU-level interrupt tests (3, 5 and 8) in sioprobe() into
a test of the irq number, and made failure of this test non-fatal.
Removed related unused complications for the APIC_IO case.  Removed the
no-test3 flag.

Deverbosified the failure messages for the other tests.  Removed the
per-port verbose flag - just use the general verbose flag.
1998-05-31 10:53:55 +00:00
Poul-Henning Kamp
e796e00de3 Some cleanups related to timecounters and weird ifdefs in <sys/time.h>.
Clean up (or if antipodic: down) some of the msgbuf stuff.

Use an inline function rather than a macro for timecounter delta.

Maintain process "on-cpu" time as 64 bits of microseconds to avoid
needless second rollover overhead.

Avoid calling microuptime the second time in mi_switch() if we do
not pass through _idle in cpu_switch()

This should reduce our context-switch overhead a bit, in particular
on pre-P5 and SMP systems.

WARNING:  Programs which muck about with struct proc in userland
will have to be fixed.

Reviewed, but found imperfect by:       bde
1998-05-28 09:30:28 +00:00
Poul-Henning Kamp
4b9afc97a7 Change a data type internal to the timecounters, and remove the "delta"
function.

Reviewed, but not entirely approved by: bde
1998-05-19 18:48:30 +00:00
Tor Egge
167a4d818c Use a higher priority interrupt vector for 8254 timer interrupts. 1998-05-17 21:15:18 +00:00
Bruce Evans
1696756396 Support compiling with `gcc -pedantic' (don't use hard newlines in
(asm) string constants or hard long long constants).
1998-04-19 15:39:26 +00:00
Dag-Erling Smørgrav
dc73342347 Seventy-odd "its" / "it's" typos in comments fixed as per kern/6108. 1998-04-17 22:37:19 +00:00
Bruce Evans
1d37f051c1 Finish supporting compiling with gcc -ansi'. Fix missing volatile's
in __asm() statements while I'm here.
1998-04-15 18:58:09 +00:00
Peter Wemm
fa1ef19485 remove #ifdef declaration of npxproc, use globals.s and the extern always. 1998-04-06 15:50:29 +00:00
Tor Egge
c547ef5cd4 Remove some unneeded statements that enabled interrupts. 1998-04-05 01:04:48 +00:00
Poul-Henning Kamp
227ee8a188 Eradicate the variable "time" from the kernel, using various measures.
"time" wasn't a atomic variable, so splfoo() protection were needed
around any access to it, unless you just wanted the seconds part.

Most uses of time.tv_sec now uses the new variable time_second instead.

gettime() changed to getmicrotime(0.

Remove a couple of unneeded splfoo() protections, the new getmicrotime()
is atomic, (until Bruce sets a breakpoint in it).

A couple of places needed random data, so use read_random() instead
of mucking about with time which isn't random.

Add a new nfs_curusec() function.

Mark a couple of bogosities involving the now disappeard time variable.

Update ffs_update() to avoid the weird "== &time" checks, by fixing the
one remaining call that passwd &time as args.

Change profiling in ncr.c to use ticks instead of time.  Resolution is
the same.

Add new function "tvtohz()" to avoid the bogus "splfoo(), add time, call
hzto() which subtracts time" sequences.

Reviewed by:	bde
1998-03-30 09:56:58 +00:00
Poul-Henning Kamp
7ab95d0bab Be less draconian about the TSC if APM is configured, use it for
timecounting if APM-BIOS isn't found.
Be just as draconian about SMP as always, but explain it better.
1998-03-16 10:06:58 +00:00
Tor Egge
c555a715f5 On SMP systems, initially follow the MP spec with regard to which pin
on the IOAPIC being connected to the 8254 timer interrupt.
Verify that timer interrupts are delivered. If they aren't, attempt
a fallback to mixed mode (i.e. routing the timer interrupt via the 8259 PIC).
1998-03-14 03:11:50 +00:00
Tor Egge
5dd528cd4e Remove special handling for resuming clock interrupt when using APIC_IO.
The `generic' vector stubs do the right thing.
1998-03-05 21:45:53 +00:00
Tor Egge
02c1dc3bbc When entering the apic version of slow interrupt handler, level
interrupts are masked, and EOI is sent iff the corresponding ISR bit
is set in the local apic. If the CPU cannot obtain the interrupt
service lock (currently the global kernel lock) the interrupt is
forwarded to the CPU holding that lock.

Clock interrupts now have higher priority than other slow interrupts.
1998-03-03 22:56:30 +00:00
Tor Egge
3163861c7b Forward the signal if the process runs on a different CPU. This reduces
the signal handling latency for cpu-bound processes that performs very
few system calls.

The IPI for forcing an additional software trap is no longer dependent upon
BETTER_CLOCK being defined.
1998-03-03 20:55:26 +00:00
Poul-Henning Kamp
3301c800f5 Prevent the TSC from being used on APM machines, we have no idea if
it runs at a constant frequency.  This was less of an issue before,
because the TSC only interpolated in the HZ intervals, but now where
the timecounter is used all the way, this becomes much more visible.

Nit: Fix a printf which triggered the bde-filter.
1998-02-28 21:16:13 +00:00
Bruce Evans
168be6199e Quick fix for the i8254 timecounter often gaining 10 msec. 1998-02-23 00:11:25 +00:00
Jordan K. Hubbard
6bf2dcfc50 Add missing CLOCK_UNLOCK() before write_eflags().
Submitted by:	dave adkins <adkin003@tc.umn.edu>
1998-02-21 20:45:27 +00:00
Poul-Henning Kamp
7ec73f6417 Replace TOD clock code with more systematic approach.
Highlights:
    * Simple model for underlying hardware.
    * Hardware basis for timekeeping can be changed on the fly.
    * Only one hardware clock responsible for TOD keeping.
    * Provides a real nanotime() function.
    * Time granularity: .232E-18 seconds.
    * Frequency granularity:  .238E-12 s/s
    * Frequency adjustment is continuous in time.
    * Less overhead for frequency adjustment.
    * Improves xntpd performance.

Reviewed by:    bde, bde, bde
1998-02-20 16:36:17 +00:00
Bruce Evans
ee10b2a475 Removed a superstitious fnop() that broke the usefulness of the FPU's
"last instruction" pointer.
1998-02-15 06:25:26 +00:00
Bruce Evans
359888780e Ifdefed SMP-only declarations. 1998-02-13 06:59:22 +00:00
Bruce Evans
1d804e7925 Update timer0_prescaler_count before calling hardclock() while timer0
is "acquired".  This fixes a TSC biasing error of about 10 msec when
pcaudio is active.

Update `time' before calling hardclock() when timer0 is being released.
This is not known to be important.

Added some delays in writertc().  Efficiency is not critical here, unlike
in rtcin(), and we already use conservative delays there.

Don't touch the hardware when machdep.i8254_freq is being changed but
the maximum count wouldn't change.  This fixes jitter of up to 10 msec
for most small adjustments to machdep.i8254_freq.  When the maximum
count needs to change, the hardware should be adjusted more carefully.
1998-02-13 06:33:16 +00:00
Bruce Evans
cd59d49d07 Only use the i586-optimized copying and zeroing functions if they are
actually faster (more than 20% faster for zeroing 1 MB at boot time).
This fixes pessimized copying and zeroing on K6's and perhaps on other
CPUs that are misclassified as i586's.
1998-02-12 21:41:10 +00:00
Eivind Eklund
303b270b0a Staticize. 1998-02-09 06:11:36 +00:00
Eivind Eklund
0b08f5f737 Back out DIAGNOSTIC changes. 1998-02-06 12:14:30 +00:00
Eivind Eklund
47cfdb166d Turn DIAGNOSTIC into a new-style option. 1998-02-04 22:34:03 +00:00
Eivind Eklund
3f2076daf5 Make the debug options new-style.
This also zaps a DPT option from lint; it wasn't referenced from
anywhere.
1998-01-31 07:23:16 +00:00
Eivind Eklund
828084926f Skip probing devices which have already probed true. 1998-01-31 03:29:00 +00:00
Poul-Henning Kamp
53dd848c82 APM calls inittodr(0) which is stupid, but at least stop setting the
clock back to when Dennis had a good idea.
1998-01-28 10:41:33 +00:00
Justin T. Gibbs
99117bb6ec Addition of splsoftvm and a VM SWI to handle bus dma related callbacks.
This SWI may be useful for other, defered, VM tasks.
1998-01-15 07:34:01 +00:00
Bruce Evans
82d86d3750 Moved the SMP declarations of INTREN() and INTRDIS() to the correct header,
i.e., the same header as corresponding non-SMP #defines.
1998-01-01 08:47:17 +00:00
Poul-Henning Kamp
0f12aa9ffd More cleanup relating to our use of the TSC.
Look in the cpu_feature (CPUID output) to see if we have it.
1997-12-28 17:33:10 +00:00
Poul-Henning Kamp
d46e059f94 wash, sort and put in order various nits from the i586_ctr -> tsc
commit.

Pointed out by: bde
1997-12-28 13:36:09 +00:00
Poul-Henning Kamp
71f461f86a Rename "i586_ctr" to "tsc" (both upper and lower case instances).
Fix a couple of printfs too.

Warning: This changes the names of a couple of kernel options!
1997-12-26 20:42:37 +00:00
Steve Passe
baf41202ca The improvements to clock statistics by Tor Egge
Wrappered and enabled by the define BETTER_CLOCK (on by default in smpyests.h)

apic_vector.s also contains a small change I (smp) made to eliminate
the double level INT problem.  It seems stable, but I haven't the tools
in place to prove it fixes the problem.

Reviewed by:	smp@csn.net
Submitted by:	Tor Egge <Tor.Egge@idi.ntnu.no>
1997-12-08 22:59:39 +00:00
John-Mark Gurney
857c08d17c fix a few style nites...
make isa_dmacascade, isa_dmastart, isa_dmadone, and find_isadev MUCH
easier to be found by starting them at the beginging of the line...

remove braces inside of ifdef RESOURCE_CHECK... found by % in vi...
1997-11-30 09:44:28 +00:00
Bruce Evans
cc8ae84672 Moved splhigh()/spl0() calls from isa_configure() to configure() so that
there is a natural place to initialize `safepri' in a future commit.
Spinoffs:
- spl0() gets called in the unlikely event that isa is not configured.
- configure() has better control over enabling interrupts.
- it is now less unclear that interrupts aren't actually enabled early.
  Rev.1.48 of autoconf.c seems to have done the opposite of what was
  intended - moving the isa_configure() call delayed the spl0() side
  effect.
Added some comments about the bogons.  Removed the splhigh() call since
it is a no-op.
1997-11-21 18:14:02 +00:00
Bruce Evans
e0605ebd12 Removed an unused #included.
Ifdefed #includes that are not used in the SMP case.
1997-11-18 11:32:31 +00:00
Bruce Evans
41d022ae9c Removed #unused includes.
Added a used #include (don't depend on yet to be fixed namespace pollution).
1997-11-18 11:16:56 +00:00
Bruce Evans
7f47cf2f4a Don't include <machine/cputypes.h> or declare cputype/class interfaces
in <machine/cpu.h>.  Moved the declarations to <machine/cputypes.h>.
Fixed style bugs in the moved code.  Fixed everything that depended on
the nested include.  Don't include <machine/cpu.h> (in the changed files)
unless something in it is used directly.
1997-10-28 11:43:57 +00:00
Jordan K. Hubbard
02630e3d73 Allow "foo0: disabled, not probed" message to stay, but make it conditional
on bootverbose so that those who _really wanna know_ still can.
Compromise suggested by:	joerg
1997-10-12 08:31:41 +00:00
Justin T. Gibbs
643b3d0cf2 Fix a serious bug I introduced while adding in support for CAM interrupts.
It seems I didn't count my 0's properly when adding the new masks into
icu_vector.s pushing SWI_AST_MASK off the end of the array and screwing
up the indexing for SWI_CLOCK_MASK.

Fix the bug icu_vector.s and also reformat the code in both icu_vector.s and
apic_vector.s so that it will be much harder to make the same mistake in
the future.

Submitted by:	Bruce Evans <bde@zeta.org.au>
1997-09-28 19:30:01 +00:00
Stephen McKay
a2575e01e8 Add a small hack to support the strange antics of the Unisys ELI 4003. This
machine generates an NMI for each floating point error, just like an old XT.
Since it is ISA only, reading the EISA status port yields 0xff, which would
give a spurious EISA panic.  The simplest thing to do is to ignore the 0xff.
1997-09-28 15:48:34 +00:00
Justin T. Gibbs
02a199102d aha1542.c aic6360.c cy.c fd.c ft.c
if_ie.c if_wl.c if_zp.c isa.c isa_device.h
labpc.c mcd.c ncr5380.c scd.c seagate.c si.c
sio.c tw.c ultra14f.c wcd.c wd.c:

	Update for changes in the callout interface.

apic_vector.s icu_vector.s ipl.s ipl_funcs.c:

	Add CAM software/hardware interrupt support.
1997-09-21 21:41:49 +00:00
John-Mark Gurney
77509afdf3 teach pnp to keep isa_device structs around, and teach isa.c how to scan
these structs for conflics...

it still exist that two PnP cards can colide, but this is up to the user
to make sure it doesn't happen...

other modifications to pnp.c to format output properly, and hide more
output behind bootverbose flag...

fix some bugons in pnp.h that would of made it difficult for inclusion
in external programs (for import of pnpinfo)
1997-09-19 15:20:25 +00:00
Peter Wemm
421f9ee1ef Change an assemble-time divide into a shift. Under binutils-2.8 gas in elf
mode, the slash is a comment leader, while under non-elf it is a divide
symbol (what a concept! :-).  Theoretically, #APP/#NO_APP can change this
but that doesn't seem to mesh too well with macros and line continuation.
1997-09-08 06:40:58 +00:00
Steve Passe
010e669615 Removed the "globl" nature of the vec array. This was left over from the
time when icu.s was common between UP and SMP.  It is not necessary for UP
and thus can be removed from icu_ipl.s.
1997-09-02 19:40:13 +00:00
Steve Passe
1de995bb1f General cleanup of the sub-system locking macros.
Eliminated the RECURSIVE_MPINTRLOCK.
clock.c and microtime use clock_lock.
sio.c and cy.c use com_lock.

Suggestions by:	Bruce Evans <bde@zeta.org.au>
1997-09-01 07:45:37 +00:00
Steve Passe
78292efeef Another round of lock pushdown.
Add a simplelock to deal with disable_intr()/enable_intr() as used in UP kernel.
UP kernel expects that this is enough to guarantee exclusive access to
regions of code bracketed by these 2 functions.
Add a simplelock to bracket clock accesses in clock.c: clock_lock.

Help from:	Bruce Evans <bde@zeta.org.au>
1997-08-30 08:08:10 +00:00
Steve Passe
34162fc615 Support for the new FAST_HI algorithm, enabled.
Preliminary support for the INTR_SIMPLELOCK algorithm, disabled.
Note that this code is NOT ready.
1997-08-29 18:45:23 +00:00
Mike Smith
67fb1e6a0c Here is a patch to alleviate the current problem with the dma interface
and the sound driver which uses auto dma.

The  dma interface functionality remains however it now checks
to see if a dma is operating in auto dma mode and if so it bypasses
the busy flag check . I have modified the sound driver 3.5  to
adjust for this new behavior and tested it under FreeBSD 3.0 -current

This patch also includes the new function isa_dmastop.

Submitted by:	Amancio Hasty <hasty@rah.star-gate.com>
1997-08-28 03:36:40 +00:00
Bruce Evans
ccea0a158a Check for irq conflicts even if conflicts are allowed. Conflicting
irqs can't work (at best, the first one attached wins).  It used to
be necessary to skip this check because of bogus irqs in the sound
drivers, but the sound drivers have been fixed, except possibly the
OSS ones.
1997-08-25 22:52:59 +00:00
Steve Passe
886e789627 The last of the encapsolation of cpl/spl/ipending things into a critical
region protected by the simplelock 'cpl_lock'.

Notes:

 - this code is currently controlled on a section by section basis with
   defines in machine/param.h.  All sections are currently enabled.

 - this code is not as clean as I would like, but that can wait till later.

 - the "giant lock" still surrounds most instances of this "cpl region".
   I still have to do the code that arbitrates setting cpl between the
   top and bottom halves of the kernel.

 - the possibility of deadlock exists, I am committing the code at this
   point so as to exercise it and detect any such cases B4 the "giant lock"
   is removed.
1997-08-24 00:05:37 +00:00
Bruce Evans
b1037dcd53 #include <machine/limits.h> explicitly in the few places that it is required. 1997-08-21 20:33:42 +00:00
Philippe Charnier
40d5099441 Revert my previous commit about using CS_SECURE macro.
Requested by:	Bruce.
1997-08-21 06:33:04 +00:00
Steve Passe
4a73d99f7e Made PEND_INTS default.
Made NEW_STRATEGY default.
Removed misc. old cruft.

Centralized simple locks into mp_machdep.c
Centralized simple lock macros into param.h

More cleanup in the direction of making splxx()/cpl MP-safe.
1997-08-21 05:08:25 +00:00
Philippe Charnier
15f3549108 Use CS_SECURE macro.
Reviewed by:	John Dyson
1997-08-18 06:58:59 +00:00
Steve Price
1393383a2e Add parentheses because == has higher precedence than &.
PR:		i386/4225
Submitted by:	Frank MacLachlan <fpm@n2.net>
1997-08-13 02:40:06 +00:00
John Dyson
48a09cf276 VM86 kernel support.
Work done by BSDI, Jonathan Lemon <jlemon@americantv.com>,
	Mike Smith <msmith@gsoft.com.au>, Sean Eric Fagan <sef@kithrup.com>,
	and probably alot of others.
Submitted by:	Jnathan Lemon <jlemon@americantv.com>
1997-08-09 00:04:06 +00:00
Mike Smith
84685adb57 Return to using disable/enable_intr() for guarding DMA register access.
Mask the read value from the count register in order to return zero correctly
after TC, as per intel datasheet : "If it is not autoinitialised, this
register will have a count of FFFFH after TC"
1997-07-29 05:24:36 +00:00
Mike Smith
f5f607a03e Pedant attack! Use variable names consistent with discourse in
comments.  Remove reduntant extra addition that was unncessary, and
unneeded mask (asuming inb works correctly).

Submitted by:	Stephen McKay <syssgm@dtir.qld.gov.au>
1997-07-28 09:13:11 +00:00
Mike Smith
53f83ec34c Use disable_intr() / read/write_eflags() to ensure that interrupt
handlers don't skew the results of isa_dmastatus.  The function can be
safely called with interrupts disabled.

Submitted by:	Stephen McKay <syssgm@dtir.qld.gov.au>
1997-07-28 07:49:40 +00:00
Steve Passe
12084b3cf1 clock.c:
- removed TEST_ALTTIMER.
 - removed APIC_PIN0_TIMER.
 - removed TIMER_ALL.

apic_vector.s:
 - new algorithm where a CPU uses try_mplock instead of get_mplock:
	if successful continue as before.
	if fail set ipending bit, mask INT (to avoid recursion), cleanup & iret.

   This allows the CPU to return to successful work, while the ISR will be run
   by the CPU holding the lock as part of the doreti dance.
1997-07-26 01:53:04 +00:00
Mike Smith
a4453045b0 Add isa_dmastatus() for reading the current ISA DMA counter for a
given channel.

Submitted by:	luigi@labinfo.iet.unipi.it (Luigi Rizzo)
1997-07-24 05:27:40 +00:00
Steve Passe
7f6ab10763 Removed the defunct GET_MPLOCK/REL_MPLOCK macros.
These are no-ops for UP, and should have been removed when vector.s
was split into UP and SMP subsets.
1997-07-24 03:24:57 +00:00
Steve Passe
87a6f31089 Last commit didn't take, operator error??? 1997-07-22 20:12:32 +00:00
Steve Passe
e94493547b Disabled 2 static inlines:
- INTRGET()
 - INTRSET()

These were only used in if_ze.c (already removed) and npx.c.  The code
in npx.c has also been cleaned of all APIC code.
1997-07-21 08:20:07 +00:00
Steve Passe
3902c3ef1f Made the SMP case ignore the possibility of an INT13 interface.
This eliminates all the APIC code, and thus several routines that
would otherwise need to be made MP-safe.

Reviewed by:	 Bruce Evans <bde@zeta.org.au>
1997-07-21 07:57:50 +00:00
Steve Passe
35b3c4a0e5 Developed a new strategy for handling the 8254/8259/APIC issue. 1997-07-20 19:41:38 +00:00
Steve Passe
0571e04aee Minor cleanup. 1997-07-20 18:02:59 +00:00
Bruce Evans
f71d35e402 Removed unused #includes. 1997-07-20 14:10:18 +00:00
Steve Passe
797cb61b54 Added #code to support define APIC_PIN0_TIMER.
This code ALWAYS runs the 8254 timer thru the 8259 ICU.
It depricates the usage of "options SMP_TIMER_NC" in the config file.
1997-07-19 03:59:28 +00:00
Steve Passe
bed422e5a3 SMP or APIC_IO:
- Increased NIDT to 256.
 - Moved IPI vectors up above the linux compat vector.
 - Removed runtime setup of RTC vector.
1997-07-19 02:28:30 +00:00
Steve Passe
d2ecb616f2 Split TEST_CPUSTOP code into CPUSTOP_ON_DDBBREAK and mainline code. 1997-07-18 21:27:53 +00:00
Steve Passe
7bbd2262eb Made the printing of the APIC INTs depend on bootverbose. 1997-07-18 03:59:28 +00:00
Peter Wemm
5611a020da Remove the disable for the P5 cpu class bcopy using the FPU on SMP kernels,
it is understood to work now (and has been for quite a while apparently).
1997-07-17 02:09:25 +00:00
Steve Passe
c064ef9175 Cleanup old stop_cpus/restart_cpus() cruft.
new code for handling mixed-mode 8259/APIC programming without 'ExtInt'
new code to control other CPUs: stop_cpus()/restart_cpus()/_Xstopcpu
1997-07-13 01:18:51 +00:00
Andrey A. Chernov
d80e841377 Back out my changes with 'conflicts' keyword for IRQs,
sounddriver fixed now.
1997-07-09 17:58:16 +00:00
Steve Passe
01bd6212ca Added a hook for a "spurious INTerrupt handler". 1997-07-06 22:11:26 +00:00
Steve Passe
58db75841d apic_vector.s:
- added Xcpustop IPI code to support stop_cpus()/restart_cpus().
   it is off by default, enable via smptests.h:TEST_CPUSTOP

intr_machdep.h:
 - moved +ICULEN to lower level.
 - added entry for Xcpustop.
1997-06-27 23:48:05 +00:00
Steve Passe
293f18dbbf Modified to use merged/renamed functions:
- get_isa_apic_mask() -> isa_apic_mask()
 - get_isa_apic_irq() && get_eisa_apic_irq() -> isa_apic_pin()
1997-06-25 21:00:00 +00:00
Peter Wemm
b3196e4b9f Preliminary support for per-cpu data pages.
This eliminates a lot of #ifdef SMP type code.  Things like _curproc reside
in a data page that is unique on each cpu, eliminating the expensive macros
like:    #define curproc (SMPcurproc[cpunumber()])

There are some unresolved bootstrap and address space sharing issues at
present, but Steve is waiting on this for other work.  There is still some
strictly temporary code present that isn't exactly pretty.

This is part of a larger change that has run into some bumps, this part is
standalone so it should be safe.  The temporary code goes away when the
full idle cpu support is finished.

Reviewed by: fsmp, dyson
1997-06-22 16:04:22 +00:00
Andrey A. Chernov
833bdc932c While deciding to install irq with unneded "conflicts" keyword,
additionly check that intr vector is non-NULL
1997-06-09 00:53:48 +00:00
Andrey A. Chernov
7f533ff73f Add safety check in case "conflicts" keyword specified more times than
needed
1997-06-08 17:15:31 +00:00
Andrey A. Chernov
1886f4968c Make "conflicts" keyword work again 1997-06-08 16:43:37 +00:00
KATO Takenori
40b2de1758 Added PC-98 code. 1997-06-02 15:28:10 +00:00
Doug Rabson
683523378c Move interrupt handling code from isa.c to a new file. This should make
isa.c (slightly) more portable and will make my life developing the really
portable version much easier.

Reviewed by:	peter, fsmp
1997-06-02 08:19:06 +00:00
Peter Wemm
5400ed3b2f Include file updates.. <machine/spl.h> -> <machine/ipl.h>, add
<machine/ipl.h> to those files that were depending on getting SWI_*
implicitly via <machine/cpufunc.h>
1997-05-31 09:27:31 +00:00
Peter Wemm
0589fe3b6e The SWI_NET_MASK and SWI_TTY_MASK handlers are now back adjacent to the
top of the hardware interrupt handlers.  Apparently this is slightly
faster with the bit scanning instruction that looks these up - this set of
changes reverts the original change.

Reviewed by: bde
1997-05-31 08:59:51 +00:00
Steve Passe
4fd20a6b2a Added code to manage the local and io APICs as structures. 1997-05-29 05:56:12 +00:00
Peter Wemm
7a14de6260 No longer need opt_smp.h here 1997-05-29 05:00:35 +00:00
Peter Wemm
ecf8148761 remove opt_smp.h from this well-included file, minor style police 1997-05-29 04:58:04 +00:00
Peter Wemm
6b19c20ba5 remove opt_smp.h, minor style police 1997-05-29 04:55:39 +00:00
Steve Passe
81c1993f87 Split vector.s into UP and SMP specific files:
- vector.s		<- stub called by i386/exception.s
 - icu_vector.s		<- UP
 - apic_vector.s	<- SMP

Split icu.s into UP and SMP specific files:
 - ipl.s		<- stub called by i386/exception.s (formerly icu.s)
 - icu_ipl.s		<- UP
 - apic_ipl.s		<- SMP

This was done in preparation for massive changes to the SMP INTerrupt
mechanisms.  More fine tuning, such as merging ipl.s into exception.s,
may be appropriate.
1997-05-26 17:58:27 +00:00
Stefan Eßer
4c9340d45c Add support for shared interrupts to the kernel. This code is meant
be (eventually) architecture independent. It provides an emulation
of the ISA interrupt registration function register_intr(), but that
function does no longer manipulated the interrupt controller and
interrupt descriptor table, but calls the architecture dependent
function setup_icu() for that purpose.

After the ISA/EISA bus code has been modified to directly call the new
interrupt registartion functions (intr_create() and intr_connect()),
the emulation of register_intr() should be dropped.

The C level interrupt handler function should take a (void*) argument,
and the function pointer type (inthand2_t) should defined in some  other
place than isa_device.h.

This commit is a pre-requisite for the removal of the PCI specific shared
interrupt code.

Reviewed by:    dfr,bde
1997-05-26 14:42:24 +00:00
Steve Passe
383243e687 Made the array vec[] a global.
This allows the APIC code to reorder the vectors at runtime.
1997-05-25 16:55:26 +00:00
Peter Wemm
06884fd04e remove now redundant (struct trapframe *) cast 1997-05-07 19:58:13 +00:00
Steve Passe
08896efb1a Code to handle SMP/APIC_IO mapping of ISA INTs to APIC pins above IRQ15.
- doesn't break my system.
 - NOT yet verified on the affected motherboard.

Stifle an annoying dma_start busy message for the sound cards.

Submitted by:	"John S. Dyson" <toor@dyson.iquest.net>
1997-05-05 22:56:13 +00:00
Peter Wemm
f435322e07 correct the order of the variables
use #ifdef where possible instead of #if defined

Submitted by: the KNF police, ie: bde :-)
1997-05-05 09:34:33 +00:00
Peter Wemm
26e5316524 Don't remove i586_ctr_freq from scope, leave it defined as zero. This
simplifies some assumptions and stops some code compile problems.

This should fix the compile hiccup in PR#3491, but smp kernel profiling
isn't likely to be fixed by this.
1997-05-04 14:25:00 +00:00
Peter Wemm
176c49e057 Use a common numbering of the tty and net software interrupt levels
between the SMP and non-SMP case.  It simplifies the #ifdef's, since
NHWI changes (at least for the moment) when APIC's are involved.
1997-04-29 20:05:48 +00:00
Steve Passe
f50a491f78 removed TEST_CPUHITS code.
replaced push/pop of %ds with use of 'ss' prefix in Xinvltlb.

Submitted by:	 Bruce Evans <bde@zeta.org.au>
1997-04-28 01:47:55 +00:00
Steve Passe
34e63b4cd7 removed all the TEST_UPPERPRIO crud. 1997-04-28 01:08:47 +00:00
Steve Passe
296bffc9c0 informal discussion between Bruce Evans <bde@zeta.org.au>,
Peter Wemm <peter@spinner.DIALix.COM>, Steve Passe <smp@csn.net>

removed all the IPI_INTS code.
made the XFAST_IPI32 code default, renaming Xfastipi32 to Xinvltlb.
cleanup of i386/isa/isa_device.h to eliminate SMP dependancies:
  made the id_irq member of struct isa_device an u_int.
  made the id_drq member of struct isa_device an int.
  removed all other '#ifdefs' concerning SMP & APIC_IO.
removed SMP/APIC_IO dependancies from if_ze.c.
1997-04-27 21:18:59 +00:00
Peter Wemm
477a642cee Man the liferafts! Here comes the long awaited SMP -> -current merge!
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!
1997-04-26 11:46:25 +00:00
John Polstra
9081eec1fb Make the necessary changes so that an ELF kernel can be built. I
have successfully built, booted, and run a number of different ELF
kernel configurations, including GENERIC.  LINT also builds and
links cleanly, though I have not tried to boot it.

The impact on developers is virtually nil, except for two things.
All linker sets that might possibly be present in the kernel must be
listed in "sys/i386/i386/setdefs.h".  And all C symbols that are
also referenced from assembly language code must be listed in
"sys/i386/include/asnames.h".  It so happens that failure to do
these things will have no impact on the a.out kernel.  But it will
break the build of the ELF kernel.

The ELF bootloader works, but it is not ready to commit quite yet.
1997-04-22 06:55:47 +00:00
Stephen McKay
bc19f8a39e Prevent wedging of the stat clock because of missed interrupts.
This should cure the "alternate system clock has died!" problem.

Discussed with: bde, joerg
1997-04-06 13:25:48 +00:00
Andrey A. Chernov
e5df661c83 Remove recently commited support for iobase == -2 ("port none")
is is really probe routine task (return -1 for no ports)
1997-03-28 01:02:17 +00:00
Andrey A. Chernov
e4960ae4f5 Replace more verbose "at <not configured>" with less verbose "at ?",
we don't need much attention here, because this diagnostic printed first
and then card will be configured.
1997-03-25 03:29:40 +00:00
Andrey A. Chernov
70b57d05df Follow config intention for iobase:
print "at <not configured>" for iobase == -1 (autodetect not happens)
and not print anything for iobase == -2 (none)
Old code treat this two special config numbers as big port numbers.
1997-03-25 03:13:05 +00:00
Bruce Evans
fce002fdef Don't include <sys/ioctl.h> in the kernel. Stage 1: don't include
it when it is not used.  In most cases, the reasons for including it
went away when the special ioctl headers became self-sufficient.
1997-03-24 11:25:10 +00:00
Bruce Evans
65ff42dd17 Only print clock calibration messages if the system was booted with -v.
Submitted by:	partly by gpalmer
1997-03-05 08:08:48 +00:00
Gary Palmer
0b146b65d2 Back out the patch to break up the clock probe lines. Instead, follow
Bruce's suggestion of deleting "relative to mc146818A clock ",
thus shortening the line ...
1997-03-05 00:54:00 +00:00
Gary Palmer
5c5e8d766c Split the rather long and line-wrapping clock probe messages on boot.
(2.2?)

Submitted by:	Mathew Dood <winter@jurai.net>
1997-03-04 09:24:01 +00:00
Peter Wemm
6875d25465 Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.
1997-02-22 09:48:43 +00:00
Bruce Evans
49a116737e Estimate an initial overhead of 0 usec instead of 20 usec in DELAY().
I have code to calibrate the overhead fairly accurately, but there
is little point in using it since it is most accurate on machines
where an estimate of 0 works well.  On slow machines, the accuracy
of DELAY() has a large variance since it is limited by the resolution
of getit() even if the initial delay is calibrated perfectly.

Use fixed point and long longs to speed up scaling in DELAY().
The old method slowed down a lot when the frequency became variable.
Assume the default frequency for short delays so that the fixed
point calculation can be exact.

Fast scaling is only important for small delays.  Scaling is done
after looking at the counter and outside the loop, so it doesn't
decrease accuracy or resolution provided it completes before the
delay is up.  The comment in the code is still confused about this.
1997-01-29 22:51:44 +00:00