removes the only reference to atrtc_set() from outside of atrtc.c, so make
it static.
The xen timer driver registers as a realtime clock with 1us resolution. In
the past that resulted in only the xen timer's clock_settime() getting
called, so it would call atrtc_set() to set the hardware clock as well. As
of r32090, the clock_settime() method of all registered realtime clocks gets
called, so the xen driver no longer needs to chain-call the lower-resolution
driver.
Thanks to royger@ for talking me through the xen stuff, and for testing.
The mutex protecting access to the registered realtime clock should not be
overloaded to protect access to the atrtc hardware, which might not even be
the registered rtc. More importantly, the resettodr mutex needs to be
eliminated to remove locking/sleeping restrictions on clock drivers, and
that can't happen if MD code for amd64 depends on it. This change moves the
protection into what's really being protected: access to the atrtc date and
time registers.
This change also adds protection when the clock is accessed from
xentimer_settime(), which bypasses the resettodr locking.
Differential Revision: https://reviews.freebsd.org/D11483
This is going to be used by the Xen clock on Dom0 in order to set the RTC of
the host. The current logic in atrtc_settime is moved to atrtc_set and the
unused device_t parameter is removed from the atrtc_set function call so it
can be safely used by other callers.
Sponsored by: Citrix Systems R&D
Reviewed by: kib, jhb
Differential revision: https://reviews.freebsd.org/D6067
Summary:
Migrate to using the semi-opaque type rman_res_t to specify rman resources. For
now, this is still compatible with u_long.
This is step one in migrating rman to use uintmax_t for resources instead of
u_long.
Going forward, this could feasibly be used to specify architecture-specific
definitions of resource ranges, rather than baking a specific integer type into
the API.
This change has been broken out to facilitate MFC'ing drivers back to 10 without
breaking ABI.
Reviewed By: jhb
Sponsored by: Alex Perez/Inertial Computing
Differential Revision: https://reviews.freebsd.org/D5075
booting on a PC with CMOS clock set to a year before 2000.
This uses 1980 (instead of 1970 as in the initial patch) as pivot year as
suggested by imp in the PR followup.
PR: 195703
Submitted by: cs@soi.spb.ru
Reviewed by: imp
MFC after: 1 weeks
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.
this code to depessimize the worst case we've lived with silently and
uneventfully for the past 12 years. Add a comment about a refinement
for those needing more assurance of accuracy.
Fix ddb's show rtc command deadlock potential when debugging rtc code
by not taking the lock if we're in the debugger. If you need a thumb
to count the number of people that have encountered this, I'd be
surprised.
Submitted by: bde
- Avoid side-effect assignments in if statements when possible.
- Don't use ! to check for NULL pointers, explicitly check against NULL.
- Explicitly check error return values against 0.
- Don't use INTR_MPSAFE for interrupt handlers with only filters as it is
meaningless.
- Remove unneeded function casts.
Old scrolls tell that once upon a time IBM AT BIOS was known to put some
useful system diagnostic information into RTC NVRAM. It is not really
known if and for how long PC BIOSes followed that convention, but I
believe that many, if not all, modern BIOSes do not do that any more
(not mentioning other types of x86 firmware).
Some diagnostic bits don't even make any sense any longer.
The check results in confusing messages upon boot on some systems.
So I am removing it.
Discussed with: bde, jhb, mav
MFC after: 3 weeks
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.
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
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.
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
