Commit Graph

217 Commits

Author SHA1 Message Date
John Baldwin
d336ab43c6 - Don't enable periodic interrupts from the RTC by default in rtc_statusb.
Instead, explicitly enable them when we setup the interrupt handler.
  Also, move the setting of stathz and profhz down to the same place so
  that the code flow is simpler and easier to follow.
- Don't setup an interrupt handler for IRQ0 if we are using the lapic timer
  as it doesn't do anything productive in that case.
2005-03-24 21:34:16 +00:00
Peter Wemm
0cd202bb09 Whitespace sync with amd64. (Rather than re-add the extra blank lines
on amd64, I'm removing them here)
2005-03-11 22:10:25 +00:00
John Baldwin
dd1d2889f2 - Remove the BURN_BRIDGES marked support for hooking into the ISA timer 0
interrupt.
- Remove the timer_func variable as it now has a static value of
  hardclock() and is only used in one place.

Axe borrowed from:	phk
2005-03-09 15:33:58 +00:00
John Baldwin
e8ce55117b Use the local APIC timer to drive the various kernel clocks on SMP machines
rather than forwarding interrupts from the clock devices around using IPIs:
- Add an IDT vector that pushes a clock frame and calls
  lapic_handle_timer().
- Add functions to program the local APIC timer including setting the
  divisor, and setting up the timer to either down a periodic countdown
  or one-shot countdown.
- Add a lapic_setup_clock() function that the BSP calls from
  cpu_init_clocks() to setup the local APIC timer if it is going to be
  used.  The setup uses a one-shot countdown to calibrate the timer.  We
  then program the timer on each CPU to fire at a frequency of hz * 3.
  stathz is defined as freq / 23 (hz * 3 / 23), and profhz is defined as
  freq / 2 (hz * 3 / 2).  This gives the clocks relatively prime divisors
  while keeping a low LCM for the frequency of the clock interrupts.
  Thanks to Peter Jeremy for suggesting this approach.
- Remove the hardclock and statclock forwarding code including the two
  associated IPIs.  The bitmap IPI handler has now effectively degenerated
  to just IPI_AST.
- When the local APIC timer is used we don't turn the RTC on at all, but
  we still enable interrupts on the ISA timer 0 (i8254) for timecounting
  purposes.
2005-02-08 20:25:07 +00:00
John Baldwin
aa96fcdb61 Anytime we write to the RTC's status B register to possibly enable
interrupts, read from the interrupt status register to clear any pending
interrupts.  Otherwise in some rare cases the RTC would never fire any
interrupts as it constantly thinks it has an interrupt pending.

PR:		i386/17800
PR:		kern/76776
Submitted by:	Jose M. Alcaide jose at we dot lc dot ehu dot es
MFC after:	2 weeks
2005-02-03 19:06:03 +00:00
Marcel Moolenaar
45cfc0a914 Partially revert previous commit. Calling getit() unconditionally fixed
a problem that could also be fixed differently without reverting previous
attempts to fix DELAY while the debugger is active (rev 1.204). The bug
was that the i8254 implements a countdown timer, while for (k)db_active
a countup timer was implemented. This resulted in premature termination
and consequently the breakage of DELAY. The fix (relative to rev 1.211)
is to implement a countdown timer for the kdb_active case. As such the
ability to step clock initialization is preserved and DELAY does what is
expected of it.

Blushed: bde :-)
Submitted by: bde
2004-07-11 17:50:59 +00:00
Marcel Moolenaar
7f46949fdf Call getit() unconditionally and only grab clock_lock when the
debugger is not active. The fixes breakages of DELAY() when
running in the debugger, because not calling getit() when the
debugger is active yields a DELAY that doesn't.
2004-07-10 22:16:18 +00:00
Poul-Henning Kamp
41ee9f1c69 Add some missing <sys/module.h> includes which are masked by the
one on death-row in <sys/kernel.h>
2004-05-30 17:57:46 +00:00
John Baldwin
d4d4ece72d Trim unused includes. 2004-05-11 20:14:53 +00:00
John Baldwin
f9acc6410e - The i8254 uses IRQ 0, not IRQ 8. Correct i8254_intsrc to reference the
correct interrupt source.
- Cache a pointer to the i8254_intsrc's pending method to avoid several
  pointer indirections in i8254_get_timecount().

Reported by:	bde
2004-04-27 20:03:26 +00:00
Warner Losh
f36cfd49ad Remove advertising clause from University of California Regent's
license, per letter dated July 22, 1999 and email from Peter Wemm,
Alan Cox and Robert Watson.

Approved by: core, peter, alc, rwatson
2004-04-07 20:46:16 +00:00
Poul-Henning Kamp
daf9092bcd Don't disable the TSC with statclock_disable. 2003-11-13 10:02:12 +00:00
John Baldwin
6f92bdd0c1 New APIC support code:
- The apic interrupt entry points have been rewritten so that each entry
  point can serve 32 different vectors.  When the entry is executed, it
  uses one of the 32-bit ISR registers to determine which vector in its
  assigned range was triggered.  Thus, the apic code can support 159
  different interrupt vectors with only 5 entry points.
- We now always to disable the local APIC to work around an errata in
  certain PPros and then re-enable it again if we decide to use the APICs
  to route interrupts.
- We no longer map IO APICs or local APICs using special page table
  entries.  Instead, we just use pmap_mapdev().  We also no longer
  export the virtual address of the local APIC as a global symbol to
  the rest of the system, but only in local_apic.c.  To aid this, the
  APIC ID of each CPU is exported as a per-CPU variable.
- Interrupt sources are provided for each intpin on each IO APIC.
  Currently, each source is given a unique interrupt vector meaning that
  PCI interrupts are not shared on most machines with an I/O APIC.
  That mapping for interrupt sources to interrupt vectors is up to the
  APIC enumerator driver however.
- We no longer probe to see if we need to use mixed mode to route IRQ 0,
  instead we always use mixed mode to route IRQ 0 for now.  This can be
  disabled via the 'NO_MIXED_MODE' kernel option.
- The npx(4) driver now always probes to see if a built-in FPU is present
  since this test can now be performed with the new APIC code.  However,
  an SMP kernel will panic if there is more than one CPU and a built-in
  FPU is not found.
- PCI interrupts are now properly routed when using APICs to route
  interrupts, so remove the hack to psuedo-route interrupts when the
  intpin register was read.
- The apic.h header was moved to apicreg.h and a new apicvar.h header
  that declares the APIs used by the new APIC code was added.
2003-11-03 21:53:38 +00:00
Warner Losh
00dc18b5a8 Per TRB vote: restore the aquire_timer0 and associated goo. This will
be gone in FreeBSD 6, so put BURN_BRIDGES around it.  The TRB also
felt that if something better comes along sooner, it can be used to
replace this code.

Delayed by: BSDcon and subsequent disk crash.
2003-09-24 15:33:33 +00:00
Bruce Evans
4df0520624 clock.c:
Quick fix for calling DELAY() for ddb input in some (atkbd-based)
console drivers.  ddb must not use any normal locks, but DELAY()
normally calls getit() which needs clock_lock.  One problem with using
normal locks in ddb is that deadlock is possible, but deadlock on
clock_lock is unlikely becaluse clock_lock is bogusly recursive,
apparently just to hide the problem of ddb using it.  The i8254 clock
hardware has mostly write-only registers so it is important for it to
use a lock that gives exclusive access.  (atkbd hardware is also
unfriendly to reentrant software but that problem is more local and
already solved.)  I mostly saw the symptoms of the bug caused by
unlocking in getit() running cpu_unpend().  cpu_unpend() should not
be called while in ddb and Debugger() calls for failing assertions
about this caused a breakpoint within ddb.

ddb must also not call getit() because ddb may be being used to step
through clock initialization code that has stopped or otherwise mangled
the clock.  If the clock is stopped, then getit() always returns the
same value and DELAY() takes forever if it trusts getit().

The quick fix is implement DELAY(n) as (n * timer_freq / 1000000)
inb(0x84)'s if ddb is active.

machdep.c:
Don't permit recursion on clock_lock.
2003-09-07 14:23:08 +00:00
Poul-Henning Kamp
78a49a45bc Give timecounters a numeric quality field.
A timecounter will be selected when registered if its quality is
not negative and no less than the current timecounters.

Add a sysctl to report all available timecounters and their qualities.

Give the dummy timecounter a solid negative quality of minus a million.

Give the i8254 zero and the ACPI 1000.

The TSC gets 800, unless APM or SMP forces it negative.

Other timecounters default to zero quality and thereby retain current
selection behaviour.
2003-08-16 08:23:53 +00:00
Poul-Henning Kamp
8dcee923b5 remove acquire_timer0() and release_timer0() and related stuff. 2003-08-15 15:50:49 +00:00
Poul-Henning Kamp
2fbc275447 Dont initialize a TSC timecounter until we know if it is broken or not. 2003-08-06 15:05:27 +00:00
David E. O'Brien
006124d811 Use __FBSDID(). 2003-06-02 16:32:55 +00:00
Poul-Henning Kamp
9a3454805e Don't rely on boolean expression evaluating to 1 or 0 by default.
Found by:       FlexeLint
2003-05-31 20:23:46 +00:00
Alexander Kabaev
104a9b7e3e Deprecate machine/limits.h in favor of new sys/limits.h.
Change all in-tree consumers to include <sys/limits.h>

Discussed on:	standards@
Partially submitted by: Craig Rodrigues <rodrigc@attbi.com>
2003-04-29 13:36:06 +00:00
Matthew N. Dodd
b7b5ae3edb Use repo-copied files in sys/i386/bios. 2003-03-24 19:14:46 +00:00
Poul-Henning Kamp
b4b138c27f Including <sys/stdint.h> is (almost?) universally only to be able to use
%j in printfs, so put a newsted include in <sys/systm.h> where the printf
prototype lives and save everybody else the trouble.
2003-03-18 08:45:25 +00:00
Poul-Henning Kamp
70d8e2e9aa Switch to using the TSC code in i386/i386/tsc.c. 2003-02-11 11:43:25 +00:00
Poul-Henning Kamp
91f1c2b3cc Split the global timezone structure into two integer fields to
prevent the compiler from optimizing assignments into byte-copy
operations which might make access to the individual fields non-atomic.

Use the individual fields throughout, and don't bother locking them with
Giant: it is no longer needed.

Inspired by:    tjr
2003-02-03 19:49:35 +00:00
Jake Burkholder
238dd3209a Split statclock into statclock and profclock, and made the method for driving
statclock based on profhz when profiling is enabled MD, since most platforms
don't use this anyway.  This removes the need for statclock_process, whose
only purpose was to subdivide profhz, and gets the profiling clock running
outside of sched_lock on platforms that implement suswintr.
Also changed the interface for starting and stopping the profiling clock to
do just that, instead of changing the rate of statclock, since they can now
be separate.

Reviewed by:	jhb, tmm
Tested on:	i386, sparc64
2003-02-03 17:53:15 +00:00
Poul-Henning Kamp
3c99c0bc50 Make tsc_freq a 64bit quantity.
Inspired by:    http://www.theinquirer.net/?article=7481
2003-01-29 11:36:39 +00:00
Poul-Henning Kamp
92a306a2b6 Use the correct value when writing the Day Of Week byte in the CMOS.
The correct range is [1...7] with Sunday=1, but we have been writing
[0...6] with Sunday=0.

The Soekris computers flagged the zero, zapped the date, so if you
rebooted your soekris on a sunday, it would come up with a wrong
date.

Bruce has a more extensive rework of this code, but we will stick with
the minimalist fix for now.

Spotted by:	Soren Kristensen <soren@soekris.com>
Thanks to:	Michael Sierchio <kudzu@tenebras.com>.
Confirmed by:	bde
Approved by:	re
2002-12-04 13:46:49 +00:00
Mitsuru IWASAKI
0ebefa8c4e 1. Fix a comment. Locking _is_ needed (but not done).
2. Update a comment.  We now restore much more than RTC updates and
   interrupts.
3. Order change.  Stop interrupts by writing to RTC_STATUSB,
   restore rate bits for the interrupts by writing to RTC_STATUSA,
   then enable interrupts again.
   This seems to be done perfectly backwards in startrtclock().
   Otherwise, the idea for this change was obtained from
   startrtclock().
4. Don't stop the clock (RTCB_HALT).  We only program some control bits
   and don't want to stop the clock.
5. (Not really related.)  Add caveats to the comment about timer_restore().
   The update is non-atomic since locking is not done.

On locking:
6. rtcin() and writertc() are locked() adequately by splhigh() in RELENG_4,
   but this locking is null in -current.
7. Doing things in the correct order in (3) combined with (6) is probably
   enough locking for rtcrestore() in RELENG_4.  In -current, the
   writertc()'s race with rtcintr() unless the BIOS disables RTC interrupts.

Submitted by:	bde (including commit message)
MFC after:	1 week
2002-10-17 13:55:39 +00:00
Poul-Henning Kamp
bc8c3c3e37 Fix a 3 year old oversight: Remove the #ifdef/#endif pair now that there
is nothing between them anymore.

Spotted by:	peter.
2002-09-21 07:59:06 +00:00
Mitsuru IWASAKI
076ef4620b Restore status register A of RTC at resume time.
This should fix the 'too many RTC interrupts and statclock seems
broken after resume' problem.

MFC after:	1 week
2002-09-18 07:34:04 +00:00
Mark Peek
5e3939b59b Clock frequencies reported by sysctl should be unsigned values. Discovered
when machdep.tsc_freq returned a negative number on a 2.2GHz Xeon.

Submitted by:	Brian Harrison <bharrison@ironport.com>
Reviewed by:	phk
MFC after:	1 week
2002-06-22 16:30:18 +00:00
Poul-Henning Kamp
2266fe776e Don't export timecounter structures under debug. with sysctl, they
contain no truly interesting data anymore.
2002-04-30 19:34:31 +00:00
Poul-Henning Kamp
7e2d76ff05 Remove the tc_update() function. Any frequency change to the
timecounter will be used starting at the next second, which is
good enough for sysctl purposes.  If better adjustment is needed
the NTP PLL should be used.
2002-04-26 10:06:26 +00:00
Matthew Dillon
d74ac6819b Compromise for critical*()/cpu_critical*() recommit. Cleanup the interrupt
disablement assumptions in kern_fork.c by adding another API call,
cpu_critical_fork_exit().  Cleanup the td_savecrit field by moving it
from MI to MD.  Temporarily move cpu_critical*() from <arch>/include/cpufunc.h
to <arch>/<arch>/critical.c (stage-2 will clean this up).

Implement interrupt deferral for i386 that allows interrupts to remain
enabled inside critical sections.  This also fixes an IPI interlock bug,
and requires uses of icu_lock to be enclosed in a true interrupt disablement.

This is the stage-1 commit.  Stage-2 will occur after stage-1 has stabilized,
and will move cpu_critical*() into its own header file(s) + other things.
This commit may break non-i386 architectures in trivial ways.  This should
be temporary.

Reviewed by:	core
Approved by:	core
2002-03-27 05:39:23 +00:00
Alfred Perlstein
89c9a48352 Remove __P. 2002-03-20 07:51:46 +00:00
Matthew Dillon
181df8c9d4 revert last commit temporarily due to whining on the lists. 2002-02-26 20:33:41 +00:00
Matthew Dillon
f96ad4c223 STAGE-1 of 3 commit - allow (but do not require) interrupts to remain
enabled in critical sections and streamline critical_enter() and
critical_exit().

This commit allows an architecture to leave interrupts enabled inside
critical sections if it so wishes.  Architectures that do not wish to do
this are not effected by this change.

This commit implements the feature for the I386 architecture and provides
a sysctl, debug.critical_mode, which defaults to 1 (use the feature).  For
now you can turn the sysctl on and off at any time in order to test the
architectural changes or track down bugs.

This commit is just the first stage.  Some areas of the code, specifically
the MACHINE_CRITICAL_ENTER #ifdef'd code, is strictly temporary and will
be cleaned up in the STAGE-2 commit when the critical_*() functions are
moved entirely into MD files.

The following changes have been made:

	* critical_enter() and critical_exit() for I386 now simply increment
	  and decrement curthread->td_critnest.  They no longer disable
	  hard interrupts.  When critical_exit() decrements the counter to
	  0 it effectively calls a routine to deal with whatever interrupts
	  were deferred during the time the code was operating in a critical
	  section.

	  Other architectures are unaffected.

	* fork_exit() has been conditionalized to remove MD assumptions for
	  the new code.  Old code will still use the old MD assumptions
	  in regards to hard interrupt disablement.  In STAGE-2 this will
	  be turned into a subroutine call into MD code rather then hardcoded
	  in MI code.

	  The new code places the burden of entering the critical section
	  in the trampoline code where it belongs.

	* I386: interrupts are now enabled while we are in a critical section.
	  The interrupt vector code has been adjusted to deal with the fact.
	  If it detects that we are in a critical section it currently defers
	  the interrupt by adding the appropriate bit to an interrupt mask.

	* In order to accomplish the deferral, icu_lock is required.  This
	  is i386-specific.  Thus icu_lock can only be obtained by mainline
	  i386 code while interrupts are hard disabled.  This change has been
	  made.

	* Because interrupts may or may not be hard disabled during a
	  context switch, cpu_switch() can no longer simply assume that
	  PSL_I will be in a consistent state.  Therefore, it now saves and
	  restores eflags.

	* FAST INTERRUPT PROVISION.  Fast interrupts are currently deferred.
	  The intention is to eventually allow them to operate either while
	  we are in a critical section or, if we are able to restrict the
	  use of sched_lock, while we are not holding the sched_lock.

	* ICU and APIC vector assembly for I386 cleaned up.  The ICU code
	  has been cleaned up to match the APIC code in regards to format
	  and macro availability.  Additionally, the code has been adjusted
	  to deal with deferred interrupts.

	* Deferred interrupts use a per-cpu boolean int_pending, and
	  masks ipending, spending, and fpending.  Being per-cpu variables
	  it is not currently necessary to lock; bus cycles modifying them.

	  Note that the same mechanism will enable preemption to be
	  incorporated as a true software interrupt without having to
	  further hack up the critical nesting code.

	* Note: the old critical_enter() code in kern/kern_switch.c is
	  currently #ifdef to be compatible with both the old and new
	  methodology.  In STAGE-2 it will be moved entirely to MD code.

Performance issues:

	One of the purposes of this commit is to enhance critical section
	performance, specifically to greatly reduce bus overhead to allow
	the critical section code to be used to protect per-cpu caches.
	These caches, such as Jeff's slab allocator work, can potentially
	operate very quickly making the effective savings of the new
	critical section code's performance very significant.

	The second purpose of this commit is to allow architectures to
	enable certain interrupts while in a critical section.  Specifically,
	the intention is to eventually allow certain FAST interrupts to
	operate rather then defer.

	The third purpose of this commit is to begin to clean up the
	critical_enter()/critical_exit()/cpu_critical_enter()/
	cpu_critical_exit() API which currently has serious cross pollution
	in MI code (in fork_exit() and ast() for example).

	The fourth purpose of this commit is to provide a framework that
	allows kernel-preempting software interrupts to be implemented
	cleanly.  This is currently used for two forward interrupts in I386.
	Other architectures will have the choice of using this infrastructure
	or building the functionality directly into critical_enter()/
	critical_exit().

	Finally, this commit is designed to greatly improve the flexibility
	of various architectures to manage critical section handling,
	software interrupts, preemption, and other highly integrated
	architecture-specific details.
2002-02-26 17:06:21 +00:00
Bruce Evans
586079cc26 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.

This was fixed in 1999 but was broken by unconditionalizing PNPBIOS.
2002-01-30 12:41:12 +00:00
John Baldwin
98f9879242 Introduce a standard name for the lock protecting an interrupt controller
and it's associated state variables: icu_lock with the name "icu".  This
renames the imen_mtx for x86 SMP, but also uses the lock to protect
access to the 8259 PIC on x86 UP.  This also adds an appropriate lock to
the various Alpha chipsets which fixes problems with Alpha SMP machines
dropping interrupts with an SMP kernel.
2001-12-20 23:48:31 +00:00
Mitsuru IWASAKI
f9390180fe Some fix for the recent apm module changes.
- Now that apm loadable module can inform its existence to other kernel
   components  (e.g. i386/isa/clock.c:startrtclock()'s TCS hack).
 - Exchange priority of SI_SUB_CPU and SI_SUB_KLD for above purpose.
 - Add simple arbitration mechanism for APM vs. ACPI.  This prevents
   the kernel enables both of them.
 - Remove obsolete `#ifdef DEV_APM' related code.
 - Add abstracted interface for Powermanagement operations.  Public apm(4)
   functions, such as apm_suspend(), should be replaced new interfaces.
   Currently only power_pm_suspend (successor of apm_suspend) is implemented.

Reviewed by:	peter, arch@ and audit@
2001-11-01 16:34:07 +00:00
Robert Drehmel
1e8ff53804 Remove an unneeded variable declaration and statement.
Approved by:	jake
2001-10-09 16:06:28 +00:00
Mitsuru IWASAKI
db2077f8e1 Reenable RTC interrupts after wakeup. Some laptops have a problem
with system statistics monitoring tools (such as systat, vmstat...)
because of stopping RTC interrupts generation.
Restore all the timers (RTC and i8254) atomically.

Reviewed by:	bde
MFC after:	1 week
2001-09-04 16:02:06 +00:00
Mike Smith
5f063c7b09 Add ACPI attachments. 2001-08-30 09:17:03 +00:00
John Baldwin
8bd57f8fc2 Remove unneeded includes of sys/ipl.h and machine/ipl.h. 2001-05-15 23:22:29 +00:00
John Baldwin
4d4bc9acc6 Add in a missing call to forward_hardclock() in the SMP case.
Submitted by:	bde
2001-04-28 01:37:44 +00:00
John Baldwin
6caa8a1501 Overhaul of the SMP code. Several portions of the SMP kernel support have
been made machine independent and various other adjustments have been made
to support Alpha SMP.

- It splits the per-process portions of hardclock() and statclock() off
  into hardclock_process() and statclock_process() respectively.  hardclock()
  and statclock() call the *_process() functions for the current process so
  that UP systems will run as before.  For SMP systems, it is simply necessary
  to ensure that all other processors execute the *_process() functions when the
  main clock functions are triggered on one CPU by an interrupt.  For the alpha
  4100, clock interrupts are delievered in a staggered broadcast fashion, so
  we simply call hardclock/statclock on the boot CPU and call the *_process()
  functions on the secondaries.  For x86, we call statclock and hardclock as
  usual and then call forward_hardclock/statclock in the MD code to send an IPI
  to cause the AP's to execute forwared_hardclock/statclock which then call the
  *_process() functions.
- forward_signal() and forward_roundrobin() have been reworked to be MI and to
  involve less hackery.  Now the cpu doing the forward sets any flags, etc. and
  sends a very simple IPI_AST to the other cpu(s).  AST IPIs now just basically
  return so that they can execute ast() and don't bother with setting the
  astpending or needresched flags themselves.  This also removes the loop in
  forward_signal() as sched_lock closes the race condition that the loop worked
  around.
- need_resched(), resched_wanted() and clear_resched() have been changed to take
  a process to act on rather than assuming curproc so that they can be used to
  implement forward_roundrobin() as described above.
- Various other SMP variables have been moved to a MI subr_smp.c and a new
  header sys/smp.h declares MI SMP variables and API's.   The IPI API's from
  machine/ipl.h have moved to machine/smp.h which is included by sys/smp.h.
- The globaldata_register() and globaldata_find() functions as well as the
  SLIST of globaldata structures has become MI and moved into subr_smp.c.
  Also, the globaldata list is only available if SMP support is compiled in.

Reviewed by:	jake, peter
Looked over by:	eivind
2001-04-27 19:28:25 +00:00
John Baldwin
f34fa851e0 Catch up to header include changes:
- <sys/mutex.h> now requires <sys/systm.h>
- <sys/mutex.h> and <sys/sx.h> now require <sys/lock.h>
2001-03-28 09:17:56 +00:00
Bruce Evans
12a586bbda Fixed style bugs in clock.c rev.1.164 and cpu.h rev.1.52-1.53 -- declare
tsc_present in the right places (together with other variables of the
same linkage), and don't use messy ifdefs just to avoid exporting it in
some cases.
2001-02-19 03:00:34 +00:00
John Baldwin
5781f5419e Catch up to changes to inthand_add(). 2001-02-09 17:48:33 +00:00