freebsd-dev/sys/arm/allwinner/timer.c

377 lines
9.5 KiB
C

/*-
* Copyright (c) 2012 Ganbold Tsagaankhuu <ganbold@freebsd.org>
* 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/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 <sys/kdb.h>
#include "a20/a20_cpu_cfg.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 SW_COUNTER64LO_REG 0xa4
#define SW_COUNTER64HI_REG 0xa8
#define CNT64_CTRL_REG 0xa0
#define CNT64_RL_EN 0x02 /* read latch enable */
#define TIMER_ENABLE (1<<0)
#define TIMER_AUTORELOAD (1<<1)
#define TIMER_OSC24M (1<<2) /* oscillator = 24mhz */
#define TIMER_PRESCALAR (0<<4) /* prescalar = 1 */
#define SYS_TIMER_CLKSRC 24000000 /* clock source */
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 timer0_freq;
struct eventtimer et;
uint8_t sc_timer_type; /* 0 for A10, 1 for A20 */
};
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 *,
sbintime_t first, sbintime_t period);
static int a10_timer_timer_stop(struct eventtimer *);
static uint64_t timer_read_counter64(void);
static int a10_timer_initialized = 0;
static int a10_timer_hardclock(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 uint64_t
timer_read_counter64(void)
{
uint32_t lo, hi;
/* In case of A20 get appropriate counter info */
if (a10_timer_sc->sc_timer_type)
return (a20_read_counter64());
/* Latch counter, wait for it to be ready to read. */
timer_write_4(a10_timer_sc, CNT64_CTRL_REG, CNT64_RL_EN);
while (timer_read_4(a10_timer_sc, CNT64_CTRL_REG) & CNT64_RL_EN)
continue;
hi = timer_read_4(a10_timer_sc, SW_COUNTER64HI_REG);
lo = timer_read_4(a10_timer_sc, SW_COUNTER64LO_REG);
return (((uint64_t)hi << 32) | lo);
}
static int
a10_timer_probe(device_t dev)
{
struct a10_timer_softc *sc;
sc = device_get_softc(dev);
if (ofw_bus_is_compatible(dev, "allwinner,sun4i-timer"))
sc->sc_timer_type = 0;
else if (ofw_bus_is_compatible(dev, "allwinner,sun7i-timer"))
sc->sc_timer_type = 1;
else
return (ENXIO);
device_set_desc(dev, "Allwinner A10/A20 timer");
return (BUS_PROBE_DEFAULT);
}
static int
a10_timer_attach(device_t dev)
{
struct a10_timer_softc *sc;
int err;
uint32_t val;
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]);
/* Setup and enable the timer interrupt */
err = bus_setup_intr(dev, sc->res[1], INTR_TYPE_CLK, a10_timer_hardclock,
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);
}
/* Set clock source to OSC24M, 16 pre-division */
val = timer_read_4(sc, SW_TIMER0_CTRL_REG);
val |= TIMER_PRESCALAR | TIMER_OSC24M;
timer_write_4(sc, SW_TIMER0_CTRL_REG, val);
/* Enable timer0 */
val = timer_read_4(sc, SW_TIMER_IRQ_EN_REG);
val |= TIMER_ENABLE;
timer_write_4(sc, SW_TIMER_IRQ_EN_REG, val);
sc->timer0_freq = SYS_TIMER_CLKSRC;
/* Set desired frequency in event timer and timecounter */
sc->et.et_frequency = sc->timer0_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 = (0x00000005LLU << 32) / sc->et.et_frequency;
sc->et.et_max_period = (0xfffffffeLLU << 32) / sc->et.et_frequency;
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 = sc->timer0_freq;
tc_init(&a10_timer_timecounter);
if (bootverbose) {
device_printf(sc->sc_dev, "clock: hz=%d stathz = %d\n", hz, stathz);
device_printf(sc->sc_dev, "event timer clock frequency %u\n",
sc->timer0_freq);
device_printf(sc->sc_dev, "timecounter clock frequency %lld\n",
a10_timer_timecounter.tc_frequency);
}
a10_timer_initialized = 1;
return (0);
}
static int
a10_timer_timer_start(struct eventtimer *et, sbintime_t first,
sbintime_t period)
{
struct a10_timer_softc *sc;
uint32_t count;
uint32_t val;
sc = (struct a10_timer_softc *)et->et_priv;
if (period != 0)
sc->sc_period = ((uint32_t)et->et_frequency * period) >> 32;
else
sc->sc_period = 0;
if (first != 0)
count = ((uint32_t)et->et_frequency * first) >> 32;
else
count = sc->sc_period;
/* Update timer values */
timer_write_4(sc, SW_TIMER0_INT_VALUE_REG, sc->sc_period);
timer_write_4(sc, SW_TIMER0_CUR_VALUE_REG, count);
val = timer_read_4(sc, SW_TIMER0_CTRL_REG);
if (period != 0) {
/* periodic */
val |= TIMER_AUTORELOAD;
} else {
/* oneshot */
val &= ~TIMER_AUTORELOAD;
}
/* Enable timer0 */
val |= TIMER_ENABLE;
timer_write_4(sc, SW_TIMER0_CTRL_REG, val);
return (0);
}
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;
/* Disable timer0 */
val = timer_read_4(sc, SW_TIMER0_CTRL_REG);
val &= ~TIMER_ENABLE;
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->timer0_freq);
}
static int
a10_timer_hardclock(void *arg)
{
struct a10_timer_softc *sc;
uint32_t val;
sc = (struct a10_timer_softc *)arg;
/* Clear interrupt pending bit. */
timer_write_4(sc, SW_TIMER_IRQ_STA_REG, 0x1);
val = timer_read_4(sc, SW_TIMER0_CTRL_REG);
/*
* Disabled autoreload and sc_period > 0 means
* timer_start was called with non NULL first value.
* Now we will set periodic timer with the given period
* value.
*/
if ((val & (1<<1)) == 0 && sc->sc_period > 0) {
/* Update timer */
timer_write_4(sc, SW_TIMER0_CUR_VALUE_REG, sc->sc_period);
/* Make periodic and enable */
val |= TIMER_AUTORELOAD | TIMER_ENABLE;
timer_write_4(sc, SW_TIMER0_CTRL_REG, val);
}
if (sc->et.et_active)
sc->et.et_event_cb(&sc->et, sc->et.et_arg);
return (FILTER_HANDLED);
}
u_int
a10_timer_get_timecount(struct timecounter *tc)
{
if (a10_timer_sc == NULL)
return (0);
return ((u_int)timer_read_counter64());
}
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;
uint64_t end, now;
if (!a10_timer_initialized) {
for (; usec > 0; usec--)
for (counter = 50; counter > 0; counter--)
cpufunc_nullop();
return;
}
now = timer_read_counter64();
end = now + (a10_timer_sc->timer0_freq / 1000000) * (usec + 1);
while (now < end)
now = timer_read_counter64();
}