freebsd-dev/sys/dev/acpica/acpi_hpet.h
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

66 lines
2.8 KiB
C

/*-
* Copyright (c) 2005 Poul-Henning Kamp
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef __ACPI_HPET_H__
#define __ACPI_HPET_H__
#define HPET_MEM_WIDTH 0x400 /* Expected memory region size */
/* General registers */
#define HPET_CAPABILITIES 0x0 /* General capabilities and ID */
#define HPET_CAP_VENDOR_ID 0xffff0000
#define HPET_CAP_LEG_RT 0x00008000
#define HPET_CAP_COUNT_SIZE 0x00002000 /* 1 = 64-bit, 0 = 32-bit */
#define HPET_CAP_NUM_TIM 0x00001f00
#define HPET_CAP_REV_ID 0x000000ff
#define HPET_PERIOD 0x4 /* Period (1/hz) of timer */
#define HPET_CONFIG 0x10 /* General configuration register */
#define HPET_CNF_LEG_RT 0x00000002
#define HPET_CNF_ENABLE 0x00000001
#define HPET_ISR 0x20 /* General interrupt status register */
#define HPET_MAIN_COUNTER 0xf0 /* Main counter register */
/* Timer registers */
#define HPET_TIMER_CAP_CNF(x) ((x) * 0x20 + 0x100)
#define HPET_TCAP_INT_ROUTE 0xffffffff00000000
#define HPET_TCAP_FSB_INT_DEL 0x00008000
#define HPET_TCNF_FSB_EN 0x00004000
#define HPET_TCNF_INT_ROUTE 0x00003e00
#define HPET_TCNF_32MODE 0x00000100
#define HPET_TCNF_VAL_SET 0x00000040
#define HPET_TCAP_SIZE 0x00000020 /* 1 = 64-bit, 0 = 32-bit */
#define HPET_TCAP_PER_INT 0x00000010 /* Supports periodic interrupts */
#define HPET_TCNF_TYPE 0x00000008 /* 1 = periodic, 0 = one-shot */
#define HPET_TCNF_INT_ENB 0x00000004
#define HPET_TCNF_INT_TYPE 0x00000002 /* 1 = level triggered, 0 = edge */
#define HPET_TIMER_COMPARATOR(x) ((x) * 0x20 + 0x108)
#define HPET_TIMER_FSB_VAL(x) ((x) * 0x20 + 0x110)
#define HPET_TIMER_FSB_ADDR(x) ((x) * 0x20 + 0x114)
#endif /* !__ACPI_HPET_H__ */