freebsd-dev/sys/arm/allwinner/timer.c
2013-01-15 09:39:11 +00:00

342 lines
8.6 KiB
C

/*-
* Copyright (c) 2012 Ganbold Tsagaankhuu <ganbold@gmail.com>
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/malloc.h>
#include <sys/rman.h>
#include <sys/timeet.h>
#include <sys/timetc.h>
#include <sys/watchdog.h>
#include <machine/bus.h>
#include <machine/cpu.h>
#include <machine/frame.h>
#include <machine/intr.h>
#include <dev/fdt/fdt_common.h>
#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <machine/bus.h>
#include <machine/fdt.h>
#include <sys/kdb.h>
/**
* Timer registers addr
*
*/
#define SW_TIMER_IRQ_EN_REG 0x00
#define SW_TIMER_IRQ_STA_REG 0x04
#define SW_TIMER0_CTRL_REG 0x10
#define SW_TIMER0_INT_VALUE_REG 0x14
#define SW_TIMER0_CUR_VALUE_REG 0x18
#define SYS_TIMER_SCAL 16 /* timer clock source pre-divsion */
#define SYS_TIMER_CLKSRC 24000000 /* timer clock source */
#define TMR_INTER_VAL SYS_TIMER_CLKSRC/(SYS_TIMER_SCAL * 1000)
#define CLOCK_TICK_RATE TMR_INTER_VAL
#define INITIAL_TIMECOUNTER (0xffffffff)
struct a10_timer_softc {
device_t sc_dev;
struct resource *res[2];
bus_space_tag_t sc_bst;
bus_space_handle_t sc_bsh;
void *sc_ih; /* interrupt handler */
uint32_t sc_period;
uint32_t clkfreq;
struct eventtimer et;
};
int a10_timer_get_timerfreq(struct a10_timer_softc *);
#define timer_read_4(sc, reg) \
bus_space_read_4(sc->sc_bst, sc->sc_bsh, reg)
#define timer_write_4(sc, reg, val) \
bus_space_write_4(sc->sc_bst, sc->sc_bsh, reg, val)
static u_int a10_timer_get_timecount(struct timecounter *);
static int a10_timer_timer_start(struct eventtimer *,
struct bintime *, struct bintime *);
static int a10_timer_timer_stop(struct eventtimer *);
static int a10_timer_initialized = 0;
static int a10_timer_intr(void *);
static int a10_timer_probe(device_t);
static int a10_timer_attach(device_t);
static struct timecounter a10_timer_timecounter = {
.tc_name = "a10_timer timer0",
.tc_get_timecount = a10_timer_get_timecount,
.tc_counter_mask = ~0u,
.tc_frequency = 0,
.tc_quality = 1000,
};
struct a10_timer_softc *a10_timer_sc = NULL;
static struct resource_spec a10_timer_spec[] = {
{ SYS_RES_MEMORY, 0, RF_ACTIVE },
{ SYS_RES_IRQ, 0, RF_ACTIVE },
{ -1, 0 }
};
static int
a10_timer_probe(device_t dev)
{
if (!ofw_bus_is_compatible(dev, "a10,timers"))
return (ENXIO);
device_set_desc(dev, "Allwinner A10 timer");
return (BUS_PROBE_DEFAULT);
}
static int
a10_timer_attach(device_t dev)
{
struct a10_timer_softc *sc;
int err;
uint32_t val;
uint32_t freq;
sc = device_get_softc(dev);
if (bus_alloc_resources(dev, a10_timer_spec, sc->res)) {
device_printf(dev, "could not allocate resources\n");
return (ENXIO);
}
sc->sc_dev = dev;
sc->sc_bst = rman_get_bustag(sc->res[0]);
sc->sc_bsh = rman_get_bushandle(sc->res[0]);
/* set interval */
timer_write_4(sc, SW_TIMER0_INT_VALUE_REG, TMR_INTER_VAL);
/* set clock source to HOSC, 16 pre-division */
val = timer_read_4(sc, SW_TIMER0_CTRL_REG);
val &= ~(0x07<<4);
val &= ~(0x03<<2);
val |= (4<<4) | (1<<2);
timer_write_4(sc, SW_TIMER0_CTRL_REG, val);
/* set mode to auto reload */
val = timer_read_4(sc, SW_TIMER0_CTRL_REG);
val |= (1<<1);
timer_write_4(sc, SW_TIMER0_CTRL_REG, val);
/* Enable timer0 */
val = timer_read_4(sc, SW_TIMER_IRQ_EN_REG);
val |= (1<<0);
timer_write_4(sc, SW_TIMER_IRQ_EN_REG, val);
/* Setup and enable the timer interrupt */
err = bus_setup_intr(dev, sc->res[1], INTR_TYPE_CLK, a10_timer_intr,
NULL, sc, &sc->sc_ih);
if (err != 0) {
bus_release_resources(dev, a10_timer_spec, sc->res);
device_printf(dev, "Unable to setup the clock irq handler, "
"err = %d\n", err);
return (ENXIO);
}
freq = SYS_TIMER_CLKSRC;
/* Set desired frequency in event timer and timecounter */
sc->et.et_frequency = (uint64_t)freq;
sc->clkfreq = (uint64_t)freq;
sc->et.et_name = "a10_timer Eventtimer";
sc->et.et_flags = ET_FLAGS_ONESHOT | ET_FLAGS_PERIODIC;
sc->et.et_quality = 1000;
sc->et.et_min_period.sec = 0;
sc->et.et_min_period.frac =
((0x00000002LLU << 32) / sc->et.et_frequency) << 32;
sc->et.et_max_period.sec = 0xfffffff0U / sc->et.et_frequency;
sc->et.et_max_period.frac =
((0xfffffffeLLU << 32) / sc->et.et_frequency) << 32;
sc->et.et_start = a10_timer_timer_start;
sc->et.et_stop = a10_timer_timer_stop;
sc->et.et_priv = sc;
et_register(&sc->et);
if (device_get_unit(dev) == 0)
a10_timer_sc = sc;
a10_timer_timecounter.tc_frequency = (uint64_t)freq;
tc_init(&a10_timer_timecounter);
printf("clock: hz=%d stathz = %d\n", hz, stathz);
device_printf(sc->sc_dev, "timer clock frequency %d\n", sc->clkfreq);
a10_timer_initialized = 1;
return (0);
}
static int
a10_timer_timer_start(struct eventtimer *et, struct bintime *first,
struct bintime *period)
{
struct a10_timer_softc *sc;
uint32_t clo, count;
sc = (struct a10_timer_softc *)et->et_priv;
if (first != NULL) {
count = (sc->et.et_frequency * (first->frac >> 32)) >> 32;
if (first->sec != 0)
count += sc->et.et_frequency * first->sec;
/* clear */
timer_write_4(sc, SW_TIMER0_CUR_VALUE_REG, 0);
clo = timer_read_4(sc, SW_TIMER0_CUR_VALUE_REG);
clo += count;
timer_write_4(sc, SW_TIMER0_CUR_VALUE_REG, clo);
return (0);
}
return (EINVAL);
}
static int
a10_timer_timer_stop(struct eventtimer *et)
{
struct a10_timer_softc *sc;
uint32_t val;
sc = (struct a10_timer_softc *)et->et_priv;
/* clear */
timer_write_4(sc, SW_TIMER0_CUR_VALUE_REG, 0);
/* disable */
val = timer_read_4(sc, SW_TIMER0_CTRL_REG);
val &= ~(1<<0); /* Disable timer0 */
timer_write_4(sc, SW_TIMER0_CTRL_REG, val);
sc->sc_period = 0;
return (0);
}
int
a10_timer_get_timerfreq(struct a10_timer_softc *sc)
{
return (sc->clkfreq);
}
void
cpu_initclocks(void)
{
cpu_initclocks_bsp();
}
static int
a10_timer_intr(void *arg)
{
struct a10_timer_softc *sc;
sc = (struct a10_timer_softc *)arg;
if (sc->et.et_active)
sc->et.et_event_cb(&sc->et, sc->et.et_arg);
/* pending */
timer_write_4(sc, SW_TIMER_IRQ_STA_REG, 0x1);
return (FILTER_HANDLED);
}
u_int
a10_timer_get_timecount(struct timecounter *tc)
{
if (a10_timer_sc == NULL)
return (0);
return (timer_read_4(a10_timer_sc, SW_TIMER0_CUR_VALUE_REG));
}
static device_method_t a10_timer_methods[] = {
DEVMETHOD(device_probe, a10_timer_probe),
DEVMETHOD(device_attach, a10_timer_attach),
DEVMETHOD_END
};
static driver_t a10_timer_driver = {
"a10_timer",
a10_timer_methods,
sizeof(struct a10_timer_softc),
};
static devclass_t a10_timer_devclass;
DRIVER_MODULE(a10_timer, simplebus, a10_timer_driver, a10_timer_devclass, 0, 0);
void
DELAY(int usec)
{
uint32_t counter;
uint32_t val, val_temp;
int32_t nticks;
/* Timer is not initialized yet */
if (!a10_timer_initialized) {
for (; usec > 0; usec--)
for (counter = 200; counter > 0; counter--)
/* Prevent optimizing out the loop */
cpufunc_nullop();
return;
}
val = timer_read_4(a10_timer_sc, SW_TIMER0_CUR_VALUE_REG);
nticks = ((a10_timer_sc->clkfreq / 1000000 + 1) * usec);
while (nticks > 0) {
val_temp = timer_read_4(a10_timer_sc, SW_TIMER0_CUR_VALUE_REG);
if (val > val_temp)
nticks -= (val - val_temp);
else
nticks -= (val + (INITIAL_TIMECOUNTER - val_temp));
val = val_temp;
}
}