/* $NetBSD: timerreg.h,v 1.5 2005/12/11 12:19:15 christos Exp $ */
/*
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Lawrence Berkeley Laboratory.
*
* 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.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* @(#)timerreg.h 8.1 (Berkeley) 6/11/93
*/
/*
* Sun-4c counter/timer registers. The timers are implemented within
* the cache chip (!). The counter and limit fields below could be
* defined as:
*
* struct {
* u_int t_limit:1, // limit reached
* t_usec:21, // counter value in microseconds
* t_mbz:10; // always zero
* };
*
* but this is more trouble than it is worth.
*
* These timers work in a rather peculiar fashion. Most clock counters
* run to 0 (as, e.g., on the VAX, where the ICR counts up to 0 from a
* large unsigned number). On the Sun-4c, it counts up to a limit. But
* for some reason, when it reaches the limit, it resets to 1, not 0.
* Thus, if the limit is set to 4, the counter counts like this:
*
* 1, 2, 3, 1, 2, 3, ...
*
* and if we want to divide by N we must set the limit register to N+1.
*
* Sun-4m counters/timer registers are similar, with these exceptions:
*
* - the limit and counter registers have changed positions..
* - both limit and counter registers are 22 bits wide, but
* they count in 500ns increments (bit 9 being the least
* significant bit).
*
* Note that we still use the `sun4c' masks and shifts to compute
* the bit pattern, given the tick period in microseconds, resulting
* in a limit value that is 1 too high. This means that (with HZ=100)
* the clock will err on the slow side by 500ns/10ms (or 0.00005 %).
* We dont bother.
*
* Sun-4u counters/timer are similar but:
*
* - the registers have been shuffled around once again. We need
* to use offsets from the 3 addresses the ROM provides us.
* - The counters are 28 bits wide with 1us accuracy.
* - You can make them do funky things with the limit register
* - They have standard 64-bit SBUS control registers.
*
* There is a problem on the Ultra5 and Ultra10. As the PCI controller
* doesn't include the timer, there are no `counter-timer' nodes here
* and so we must use %tick.
*/
#ifndef _LOCORE
struct timer_4 {
volatile int t_counter; /* counter reg */
volatile int t_limit; /* limit reg */
};
struct timerreg_4 {
struct timer_4 t_c10; /* counter that interrupts at ipl 10 */
struct timer_4 t_c14; /* counter that interrupts at ipl 14 */
};
struct timer_4m { /* counter that interrupts at ipl 10 */
volatile int t_limit; /* limit register */
volatile int t_counter; /* counter register */
volatile int t_limit_nr; /* limit reg, non-resetting */
volatile int t_reserved;
volatile int t_cfg; /* a configuration register */
/*
* Note: The SparcClassic manual only defines this one bit
* I suspect there are more in multi-processor machines.
*/
#define TMR_CFG_USER 1
};
struct timer_4u {
volatile int64_t t_count; /* counter reg */
volatile int64_t t_limit; /* limit reg */
#define TMR_LIM_IEN 0x80000000 /* interrupt enable bit */
#define TMR_LIM_RELOAD 0x40000000 /* reload counter to 0 */
#define TMR_LIM_PERIODIC 0x20000000 /* reset when limit is reached */
#define TMR_LIM_MASK 0x1fffffff
};
struct timerreg_4u {
struct timer_4u* t_timer; /* There are two of them */
volatile int64_t* t_clrintr; /* There are two of these, too. */
volatile int64_t* t_mapintr; /* Same here. */
};
struct counter_4m { /* counter that interrupts at ipl 14 */
volatile int t_limit; /* limit register */
volatile int t_counter; /* counter register */
volatile int t_limit_nr; /* limit reg, non-resetting */
volatile int t_ss; /* Start/Stop register */
#define TMR_USER_RUN 1
};
#endif /* _LOCORE */
#define TMR_LIMIT 0x80000000 /* counter reached its limit */
#define TMR_SHIFT 10 /* shift to obtain microseconds */
#define TMR_MASK 0x1fffff /* 21 bits */
/* Compute a limit that causes the timer to fire every n microseconds. */
/* #define tmr_ustolim(n) (((n) + 1) << TMR_SHIFT) */
#define tmr_ustolim(n) ((n))
/*efine TMR_SHIFT4M 9 -* shift to obtain microseconds */
/*efine tmr_ustolim(n) (((2*(n)) + 1) << TMR_SHIFT4M)*/