vHPET is used as a source of system timer by UEFI (e.g. OVMF).
This provides an alternative to using vPIT, which OVMF assumes is always
connected to vPIC.
This is ported from Bhyve, with a few changes:
- move to user space, using acrn_timer
- enable timers only when necessary
Origin: FreeBSD
License: BSD-3-Clause
URL: https://svnweb.freebsd.org/
commit: 326257
Purpose: Adding vHPET support.
Maintained-by: External
Tracked-On: #2319
Signed-off-by: Peter Fang <peter.fang@intel.com>
Acked-by: Anthony Xu <anthony.xu@intel.com>
It is possible for multiple timeouts to occur in one mevent epoll
iteration. Providing the number of timer expirations to the timer
callback handlers can be useful. E.g., this could improve emulation of
timing-sensitive hardware components.
Tracked-On: #2319
Signed-off-by: Peter Fang <peter.fang@intel.com>
Acked-by: Anthony Xu <anthony.xu@intel.com>
Allow specifying the initial expiration in absolute time.
Tracked-On: #2319
Signed-off-by: Peter Fang <peter.fang@intel.com>
Acked-by: Anthony Xu <anthony.xu@intel.com>
We will use timerfd and epoll mechanism to emulate kinds of timers like
PIT/RTC/WDT/PMTIMER/... in device model under Linux. The api is unified
in this patch.
Compare with sigevent mechanism, timerfd has a advantage that it could
avoid race condition on resource accessing in the async sigev thread.
change log:
v1 -> v2: add NULL pointer check for function parameter;
v2 -> v3: rename file name of vtimer.* to timer.*;
rename structure name of vtimer to acrn_timer;
add read() in timer handler to consume I/O event;
v3 -> v4: replace bool clock_realtime with int clockid;
close acrn_timer->fd properly;
Tracked-On: #1489
Signed-off-by: Victor Sun <victor.sun@intel.com>
Reviewed-by: Jian Jun Chen <jian.jun.chen@intel.com>
Acked-by: Yin Fengwei <fengwei.yin@intel.com>
Peter Fang