319 lines
7.9 KiB
C
319 lines
7.9 KiB
C
/* $NetBSD: s3c24x0_clk.c,v 1.10 2008/07/04 11:59:45 bsh Exp $ */
|
|
|
|
/*
|
|
* Copyright (c) 2003 Genetec corporation. All rights reserved.
|
|
* Written by Hiroyuki Bessho for Genetec corporation.
|
|
*
|
|
* 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. The name of Genetec corporation may not be used to endorse
|
|
* or promote products derived from this software without specific prior
|
|
* written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY GENETEC CORP. ``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 GENETEC CORP.
|
|
* 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.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__KERNEL_RCSID(0, "$NetBSD: s3c24x0_clk.c,v 1.10 2008/07/04 11:59:45 bsh Exp $");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/atomic.h>
|
|
#include <sys/time.h>
|
|
#include <sys/timetc.h>
|
|
|
|
#include <machine/bus.h>
|
|
#include <machine/intr.h>
|
|
#include <arm/cpufunc.h>
|
|
|
|
#include <arm/s3c2xx0/s3c24x0reg.h>
|
|
#include <arm/s3c2xx0/s3c24x0var.h>
|
|
|
|
|
|
#ifndef STATHZ
|
|
#define STATHZ 64
|
|
#endif
|
|
|
|
#define TIMER_FREQUENCY(pclk) ((pclk)/16) /* divider=1/16 */
|
|
|
|
static unsigned int timer4_reload_value;
|
|
static unsigned int timer4_prescaler;
|
|
static unsigned int timer4_mseccount;
|
|
|
|
#define usec_to_counter(t) \
|
|
((timer4_mseccount*(t))/1000)
|
|
|
|
#define counter_to_usec(c,pclk) \
|
|
(((c)*timer4_prescaler*1000)/(TIMER_FREQUENCY(pclk)/1000))
|
|
|
|
static u_int s3c24x0_get_timecount(struct timecounter *);
|
|
|
|
static struct timecounter s3c24x0_timecounter = {
|
|
s3c24x0_get_timecount, /* get_timecount */
|
|
0, /* no poll_pps */
|
|
0xffffffff, /* counter_mask */
|
|
0, /* frequency */
|
|
"s3c234x0", /* name */
|
|
100, /* quality */
|
|
NULL, /* prev */
|
|
NULL, /* next */
|
|
};
|
|
|
|
static volatile uint32_t s3c24x0_base;
|
|
|
|
static u_int
|
|
s3c24x0_get_timecount(struct timecounter *tc)
|
|
{
|
|
struct s3c24x0_softc *sc = (struct s3c24x0_softc *) s3c2xx0_softc;
|
|
int save, int_pend0, int_pend1, count;
|
|
|
|
save = disable_interrupts(I32_bit);
|
|
|
|
again:
|
|
int_pend0 = S3C24X0_INT_TIMER4 &
|
|
bus_space_read_4(sc->sc_sx.sc_iot, sc->sc_sx.sc_intctl_ioh,
|
|
INTCTL_SRCPND);
|
|
count = bus_space_read_2(sc->sc_sx.sc_iot, sc->sc_timer_ioh,
|
|
TIMER_TCNTO(4));
|
|
|
|
for (;;) {
|
|
|
|
int_pend1 = S3C24X0_INT_TIMER4 &
|
|
bus_space_read_4(sc->sc_sx.sc_iot, sc->sc_sx.sc_intctl_ioh,
|
|
INTCTL_SRCPND);
|
|
if( int_pend0 == int_pend1 )
|
|
break;
|
|
|
|
/*
|
|
* Down counter reached to zero while we were reading
|
|
* timer values. do it again to get consistent values.
|
|
*/
|
|
int_pend0 = int_pend1;
|
|
count = bus_space_read_2(sc->sc_sx.sc_iot, sc->sc_timer_ioh,
|
|
TIMER_TCNTO(4));
|
|
}
|
|
|
|
if (__predict_false(count > timer4_reload_value)) {
|
|
/*
|
|
* Buggy Hardware Warning --- sometimes timer counter
|
|
* reads bogus value like 0xffff. I guess it happens when
|
|
* the timer is reloaded.
|
|
*/
|
|
printf("Bogus value from timer counter: %d\n", count);
|
|
goto again;
|
|
}
|
|
|
|
restore_interrupts(save);
|
|
|
|
if (int_pend1)
|
|
count -= timer4_reload_value;
|
|
|
|
return s3c24x0_base - count;
|
|
}
|
|
|
|
static inline int
|
|
read_timer(struct s3c24x0_softc *sc)
|
|
{
|
|
int count;
|
|
|
|
do {
|
|
count = bus_space_read_2(sc->sc_sx.sc_iot, sc->sc_timer_ioh,
|
|
TIMER_TCNTO(4));
|
|
} while ( __predict_false(count > timer4_reload_value) );
|
|
|
|
return count;
|
|
}
|
|
|
|
/*
|
|
* delay:
|
|
*
|
|
* Delay for at least N microseconds.
|
|
*/
|
|
void
|
|
delay(u_int n)
|
|
{
|
|
struct s3c24x0_softc *sc = (struct s3c24x0_softc *) s3c2xx0_softc;
|
|
int v0, v1, delta;
|
|
u_int ucnt;
|
|
|
|
if ( timer4_reload_value == 0 ){
|
|
/* not initialized yet */
|
|
while ( n-- > 0 ){
|
|
int m;
|
|
|
|
for (m=0; m<100; ++m )
|
|
;
|
|
}
|
|
return;
|
|
}
|
|
|
|
/* read down counter */
|
|
v0 = read_timer(sc);
|
|
|
|
ucnt = usec_to_counter(n);
|
|
|
|
while( ucnt > 0 ) {
|
|
v1 = read_timer(sc);
|
|
delta = v0 - v1;
|
|
if ( delta < 0 )
|
|
delta += timer4_reload_value;
|
|
#ifdef DEBUG
|
|
if (delta < 0 || delta > timer4_reload_value)
|
|
panic("wrong value from timer counter");
|
|
#endif
|
|
|
|
if((u_int)delta < ucnt){
|
|
ucnt -= (u_int)delta;
|
|
v0 = v1;
|
|
}
|
|
else {
|
|
ucnt = 0;
|
|
}
|
|
}
|
|
/*NOTREACHED*/
|
|
}
|
|
|
|
void
|
|
setstatclockrate(int newhz)
|
|
{
|
|
}
|
|
|
|
static int
|
|
hardintr(void *arg)
|
|
{
|
|
atomic_add_32(&s3c24x0_base, timer4_reload_value);
|
|
|
|
hardclock((struct clockframe *)arg);
|
|
|
|
return 1;
|
|
}
|
|
|
|
void
|
|
cpu_initclocks(void)
|
|
{
|
|
struct s3c24x0_softc *sc = (struct s3c24x0_softc *)s3c2xx0_softc;
|
|
long tc;
|
|
int prescaler, h;
|
|
int pclk = s3c2xx0_softc->sc_pclk;
|
|
bus_space_tag_t iot = sc->sc_sx.sc_iot;
|
|
bus_space_handle_t ioh = sc->sc_timer_ioh;
|
|
uint32_t reg;
|
|
|
|
stathz = STATHZ;
|
|
profhz = stathz;
|
|
|
|
#define time_constant(hz) (TIMER_FREQUENCY(pclk) /(hz)/ prescaler)
|
|
#define calc_time_constant(hz) \
|
|
do { \
|
|
prescaler = 1; \
|
|
do { \
|
|
++prescaler; \
|
|
tc = time_constant(hz); \
|
|
} while( tc > 65536 ); \
|
|
} while(0)
|
|
|
|
|
|
/* Use the channels 4 and 3 for hardclock and statclock, respectively */
|
|
|
|
/* stop all timers */
|
|
bus_space_write_4(iot, ioh, TIMER_TCON, 0);
|
|
|
|
/* calc suitable prescaler value */
|
|
h = MIN(hz,stathz);
|
|
calc_time_constant(h);
|
|
|
|
timer4_prescaler = prescaler;
|
|
timer4_reload_value = TIMER_FREQUENCY(pclk) / hz / prescaler;
|
|
timer4_mseccount = TIMER_FREQUENCY(pclk)/timer4_prescaler/1000 ;
|
|
|
|
bus_space_write_4(iot, ioh, TIMER_TCNTB(4),
|
|
((prescaler - 1) << 16) | (timer4_reload_value - 1));
|
|
|
|
printf("clock: hz=%d stathz = %d PCLK=%d prescaler=%d tc=%ld\n",
|
|
hz, stathz, pclk, prescaler, tc);
|
|
|
|
bus_space_write_4(iot, ioh, TIMER_TCNTB(3),
|
|
((prescaler - 1) << 16) | (time_constant(stathz) - 1));
|
|
|
|
s3c24x0_intr_establish(S3C24X0_INT_TIMER4, IPL_CLOCK,
|
|
IST_NONE, hardintr, 0);
|
|
#ifdef IPL_STATCLOCK
|
|
s3c24x0_intr_establish(S3C24X0_INT_TIMER3, IPL_STATCLOCK,
|
|
IST_NONE, statintr, 0);
|
|
#endif
|
|
|
|
/* set prescaler1 */
|
|
reg = bus_space_read_4(iot, ioh, TIMER_TCFG0);
|
|
bus_space_write_4(iot, ioh, TIMER_TCFG0,
|
|
(reg & ~0xff00) | ((prescaler-1) << 8));
|
|
|
|
/* divider 1/16 for ch #3 and #4 */
|
|
reg = bus_space_read_4(iot, ioh, TIMER_TCFG1);
|
|
bus_space_write_4(iot, ioh, TIMER_TCFG1,
|
|
(reg & ~(TCFG1_MUX_MASK(3)|TCFG1_MUX_MASK(4))) |
|
|
(TCFG1_MUX_DIV16 << TCFG1_MUX_SHIFT(3)) |
|
|
(TCFG1_MUX_DIV16 << TCFG1_MUX_SHIFT(4)) );
|
|
|
|
|
|
/* start timers */
|
|
reg = bus_space_read_4(iot, ioh, TIMER_TCON);
|
|
reg &= ~(TCON_MASK(3)|TCON_MASK(4));
|
|
|
|
/* load the time constant */
|
|
bus_space_write_4(iot, ioh, TIMER_TCON, reg |
|
|
TCON_MANUALUPDATE(3) | TCON_MANUALUPDATE(4));
|
|
/* set auto reload and start */
|
|
bus_space_write_4(iot, ioh, TIMER_TCON, reg |
|
|
TCON_AUTORELOAD(3) | TCON_START(3) |
|
|
TCON_AUTORELOAD(4) | TCON_START(4) );
|
|
|
|
s3c24x0_timecounter.tc_frequency = TIMER_FREQUENCY(pclk) / timer4_prescaler;
|
|
tc_init(&s3c24x0_timecounter);
|
|
}
|
|
|
|
|
|
#if 0
|
|
/* test routine for delay() */
|
|
|
|
void delay_test(void);
|
|
void
|
|
delay_test(void)
|
|
{
|
|
struct s3c2xx0_softc *sc = s3c2xx0_softc;
|
|
volatile int *pdatc = (volatile int *)
|
|
((char *)bus_space_vaddr(sc->sc_iot, sc->sc_gpio_ioh) + GPIO_PDATC);
|
|
static const int d[] = {0, 1, 5, 10, 50, 100, 500, 1000, -1};
|
|
int i;
|
|
int v = *pdatc & ~0x07;
|
|
|
|
for (;;) {
|
|
*pdatc = v | 2;
|
|
|
|
for (i=0; d[i] >= 0; ++i) {
|
|
*pdatc = v | 3;
|
|
delay(d[i]);
|
|
*pdatc = v | 2;
|
|
}
|
|
*pdatc = v;
|
|
}
|
|
}
|
|
#endif
|
|
|