Commit Graph

33 Commits

Author SHA1 Message Date
Roger Pau Monné
5f05c79450 xen: implement an early timer for Xen PVH
When running as a PVH guest, there's no emulated i8254, so we need to
use the Xen PV timer as the early source for DELAY. This change allows
for different implementations of the early DELAY function and
implements a Xen variant for it.

Approved by: gibbs
Sponsored by: Citrix Systems R&D

dev/xen/timer/timer.c:
dev/xen/timer/timer.h:
 - Implement Xen early delay functions using the PV timer and declare
   them.

x86/include/init.h:
 - Add hooks for early clock source initialization and early delay
   functions.

i386/i386/machdep.c:
pc98/pc98/machdep.c:
amd64/amd64/machdep.c:
 - Set early delay hooks to use the i8254 on bare metal.
 - Use clock_init (that will in turn make use of init_ops) to
   initialize the early clock source.

amd64/include/clock.h:
i386/include/clock.h:
 - Declare i8254_delay and clock_init.

i386/xen/clock.c:
 - Rename DELAY to i8254_delay.

x86/isa/clock.c:
 - Introduce clock_init that will take care of initializing the early
   clock by making use of the init_ops hooks.
 - Move non ISA related delay functions to the newly introduced delay
   file.

x86/x86/delay.c:
 - Add moved delay related functions.
 - Implement generic DELAY function that will use the init_ops hooks.

x86/xen/pv.c:
 - Set PVH hooks for the early delay related functions in init_ops.

conf/files.amd64:
conf/files.i386:
conf/files.pc98:
 - Add delay.c to the kernel build.
2014-03-11 10:20:42 +00:00
Brooks Davis
cb261f4315 Call set_i8254_freq with MODE_STOP (0) rather than a magic number of 0. 2013-08-15 17:21:06 +00:00
Alexander Motin
fdc5dd2d2f MFcalloutng:
Switch eventtimers(9) from using struct bintime to sbintime_t.
Even before this not a single driver really supported full dynamic range of
struct bintime even in theory, not speaking about practical inexpediency.
This change legitimates the status quo and cleans up the code.
2013-02-28 13:46:03 +00:00
Warner Losh
85e51e4918 Correct comment about use of pmtimer, and the real reason it isn't
used or desirable for amd64.
2013-02-21 06:38:24 +00:00
Davide Italiano
ce4642ecd5 Fixup r246916 in case gcc is used to build.
Reported by:	attilio, simon
2013-02-19 16:43:48 +00:00
Alexander Motin
a937c5078f MFcalloutng:
Microoptimize i8254 one-shot operation mode (disabled by default to allow
timecounter functionality) by not writing to mode and MSB registers when
it is not required.  This saves several microseconds of CPU time per call,
reducing minimal measured interrupts interval to 19.5us.
2013-02-17 18:42:30 +00:00
Jung-uk Kim
65e7d70b09 Implement boot-time TSC synchronization test for SMP. This test is executed
when the user has indicated that the system has synchronized TSCs or it has
P-state invariant TSCs.  For the former case, we may clear the tunable if it
fails the test to prevent accidental foot-shooting.  For the latter case, we
may set it if it passes the test to notify the user that it may be usable.
2011-05-09 17:34:00 +00:00
Jung-uk Kim
8143750196 Use newly added rdtsc32() for DELAY(9) as well. 2011-04-14 19:11:45 +00:00
Jung-uk Kim
5331d61da4 Add some tunable descriptions about x86 timers.
Requested by:	arundel
2011-04-14 00:07:08 +00:00
Jung-uk Kim
e94d5ad227 Do not use TSC for DELAY(9) if it not P-state invariant to avoid possible
foot-shooting.  DELAY() becomes unreliable when TSC frequency varies wildly,
especially cpufreq(4) and powerd(8) are used at the same time.
2011-04-12 22:41:52 +00:00
Jung-uk Kim
57d7a7fb0a Merge two similar functions to reduce duplication. 2011-04-11 19:27:44 +00:00
Jung-uk Kim
80c2cdcffe Refactor DELAYDEBUG as it is only useful for correcting i8254 frequency. 2011-04-08 19:54:29 +00:00
Jung-uk Kim
3453537fa5 Use atomic load & store for TSC frequency. It may be overkill for amd64 but
safer for i386 because it can be easily over 4 GHz now.  More worse, it can
be easily changed by user with 'machdep.tsc_freq' tunable (directly) or
cpufreq(4) (indirectly).  Note it is intentionally not used in performance
critical paths to avoid performance regression (but we should, in theory).
Alternatively, we may add "virtual TSC" with lower frequency if maximum
frequency overflows 32 bits (and ignore possible incoherency as we do now).
2011-04-07 23:28:28 +00:00
Jung-uk Kim
856e88c1f5 When TSC is unavailable, broken or disabled and the current timecounter has
better quality than i8254 timer, use it for DELAY(9).
2011-03-14 22:05:59 +00:00
Jung-uk Kim
bc34c87e81 Deprecate rarely used tsc_is_broken. Instead, we zero out tsc_freq because
it is almost always used with tsc_freq any way.
2011-03-10 20:02:58 +00:00
Rebecca Cran
974206cf70 Fix typos - remove duplicate "is".
PR:		docs/154934
Submitted by:	Eitan Adler <lists at eitanadler.com>
MFC after:	3 days
2011-02-23 09:22:33 +00:00
Alexander Motin
d3979248ac Restore pre-r212778 optimization, skipping timer reprogramming when it is
not neccessary. It allows to avoid time counter jump of up to 1/18s, when
base frequency slightly tuned via machdep.i8254_freq sysctl.
Fix few style things.

Suggested by:	bde
2010-09-18 07:36:43 +00:00
Alexander Motin
9500655e5a Add one-shot mode support to attimer (i8254) event timer.
Unluckily, using one-shot mode is impossible, when same hardware used for
time counting. Introduce new tunable hint.attimer.0.timecounter, setting
which to 0 disables i8254 time counter and allows one-shot mode. Note,
that on some systems there may be no other reliable enough time counters,
so this tunable should be used with understanding.
2010-09-17 04:48:50 +00:00
Alexander Motin
599cf0f197 Fix several un-/signedness bugs of r210290 and r210293. Add one more check. 2010-07-20 15:48:29 +00:00
Alexander Motin
51636352b6 Extend timer driver API to report also minimal and maximal supported period
lengths. Make MI wrapper code to validate periods in request. Make kernel
clock management code to honor these hardware limitations while choosing hz,
stathz and profhz values.
2010-07-20 10:58:56 +00:00
Alexander Motin
8a6870808d Rise knowledge about curthread->td_intr_frame by one step. Make timer
callback argument really opaque. Not repeat interrupt handler's problem
in case somebody will ever need to have both argument and frame.
2010-07-13 12:46:06 +00:00
Alexander Motin
75e24dd8ce Unify pc98 event timer code with the rest of x86.
Reviewed by:	nyan@
2010-07-13 06:57:27 +00:00
Alexander Motin
91751b1a86 Instead of deleting existing IRQ resource, which is not really working for
ACPI bus, find wanted IRQ rid or spare one. This should fix panic during
boot on systems reporting fancy IRQ numbers for attimer and atrtc.
2010-07-12 06:46:17 +00:00
Alexander Motin
a7d6757c3e Allow attimer to be hinted at ISA if not reported by ISA PNP or ACPI.
Rephrase respective atrtc code same way to be more readable.
2010-07-01 18:59:05 +00:00
Alexander Motin
6019ba4e4b Rework r209456:
Instead of using fake rid (which ISA doesn't like), delete untrusted
IRQ resource and let it be recreated.
2010-07-01 18:51:18 +00:00
Alexander Motin
926911c8ff Do not trust IRQ reported by ACPI. There are cases when it is wrong. 2010-06-23 05:43:21 +00:00
Alexander Motin
49ed68bbf3 Add "legacy route" support to HPET driver. When enabled, this mode makes
HPET to steal IRQ0 from i8254 and IRQ8 from RTC timers. It can be suitable
for HPETs without FSB interrupts support, as it gives them two unshared
IRQs. It allows them to provide one per-CPU event timer on dual-CPU system,
that should be suitable for further tickless kernels.

To enable it, such lines may be added to /boot/loader.conf:
hint.atrtc.0.clock=0
hint.attimer.0.clock=0
hint.hpet.0.legacy_route=1
2010-06-22 19:42:27 +00:00
Alexander Motin
875b8844be Implement new event timers infrastructure. It provides unified APIs for
writing event timer drivers, for choosing best possible drivers by machine
independent code and for operating them to supply kernel with hardclock(),
statclock() and profclock() events in unified fashion on various hardware.

Infrastructure provides support for both per-CPU (independent for every CPU
core) and global timers in periodic and one-shot modes. MI management code
at this moment uses only periodic mode, but one-shot mode use planned for
later, as part of tickless kernel project.

For this moment infrastructure used on i386 and amd64 architectures. Other
archs are welcome to follow, while their current operation should not be
affected.

This patch updates existing drivers (i8254, RTC and LAPIC) for the new
order, and adds event timers support into the HPET driver. These drivers
have different capabilities:
 LAPIC - per-CPU timer, supports periodic and one-shot operation, may
freeze in C3 state, calibrated on first use, so may be not exactly precise.
 HPET - depending on hardware can work as per-CPU or global, supports
periodic and one-shot operation, usually provides several event timers.
 i8254 - global, limited to periodic mode, because same hardware used also
as time counter.
 RTC - global, supports only periodic mode, set of frequencies in Hz
limited by powers of 2.

Depending on hardware capabilities, drivers preferred in following orders,
either LAPIC, HPETs, i8254, RTC or HPETs, LAPIC, i8254, RTC.
User may explicitly specify wanted timers via loader tunables or sysctls:
kern.eventtimer.timer1 and kern.eventtimer.timer2.
If requested driver is unavailable or unoperational, system will try to
replace it. If no more timers available or "NONE" specified for second,
system will operate using only one timer, multiplying it's frequency by few
times and uing respective dividers to honor hz, stathz and profhz values,
set during initial setup.
2010-06-20 21:33:29 +00:00
Alexander Motin
dbd55f3ff0 - Implement MI helper functions, dividing one or two timer interrupts with
arbitrary frequencies into hardclock(), statclock() and profclock() calls.
Same code with minor variations duplicated several times over the tree for
different timer drivers and architectures.
- Switch all x86 archs to new functions, simplifying the code and removing
extra logic from timer drivers. Other archs are also welcome.
2010-05-24 11:40:49 +00:00
Rui Paulo
f79727118c Fix another instance of lapic_cyclic_clock_func. 2010-04-20 21:04:57 +00:00
Attilio Rao
17586b1af8 Default the machdep.lapic_allclocks to be enabled in order to cope with
broken atrtc.
Now if you want more correct stats on profhz and stathz it may be
disabled by setting to 0.

Reported by:	A. Akephalos <akephalos dot akephalos at gmail dot com>,
		Jakub Lach <jakub_lach at mailplus dot pl>
MFC:		1 week
2010-04-09 14:22:09 +00:00
Attilio Rao
306c0c6ea0 Improving the clocks auto-tunning by firstly checking if the atrtc may be
correctly initialized and just then assign to softclock/profclock.
Right now, some atrtc seems reporting strange diagnostic error* making the
current pattern bogus.

In order to do that cleanly, lapic_setup_clock(), on both ia32 and amd64,
now accepts as arguments the desired sources to handle, and returns the
actual ones (LAPIC_CLOCK_NONE is forbidden because otherwise there is no
meaning in calling such function).
This allows to bring out into commont x86 code the handling part for
machdep.lapic_allclocks tunable, which is retained.

Sponsored by:	Sandvine Incorporated
Tested by:	yongari, Richard Todd
		<rmtodd at ichotolot dot servalan dot com>
MFC:		3 weeks
X-MFC:		r202387, 204309
2010-03-03 17:13:29 +00:00
Attilio Rao
3258030144 Introduce the new kernel sub-tree x86 which should contain all the code
shared and generalized between our current amd64, i386 and pc98.

This is just an initial step that should lead to a more complete effort.
For the moment, a very simple porting of cpufreq modules, BIOS calls and
the whole MD specific ISA bus part is added to the sub-tree but ideally
a lot of code might be added and more shared support should grow.

Sponsored by:	Sandvine Incorporated
Reviewed by:	emaste, kib, jhb, imp
Discussed on:	arch
MFC:		3 weeks
2010-02-25 14:13:39 +00:00