netbsd/sys/arch/arm/allwinner/awin_cnt.c
2015-10-15 10:25:28 +02:00

133 lines
4.0 KiB
C

/* $NetBSD: awin_cnt.c,v 1.3 2015/04/01 07:44:18 skrll Exp $ */
/*-
* Copyright (c) 2014 Jared D. McNeill <jmcneill@invisible.ca>
* 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 ``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 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 "opt_multiprocessor.h"
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: awin_cnt.c,v 1.3 2015/04/01 07:44:18 skrll Exp $");
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/device.h>
#include <sys/intr.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/timetc.h>
#include <arm/allwinner/awin_reg.h>
#include <arm/allwinner/awin_var.h>
struct awin_cnt_softc {
device_t sc_dev;
bus_space_tag_t sc_bst;
bus_space_handle_t sc_bsh;
struct timecounter sc_tc;
kmutex_t sc_lock;
};
#define CNT_READ(sc, reg) \
bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg))
#define CNT_WRITE(sc, reg, val) \
bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val))
static int awin_cnt_match(device_t, cfdata_t, void *);
static void awin_cnt_attach(device_t, device_t, void *);
static u_int awin_cnt_get_timecount(struct timecounter *);
CFATTACH_DECL_NEW(awin_cnt, sizeof(struct awin_cnt_softc),
awin_cnt_match, awin_cnt_attach, NULL, NULL);
static int
awin_cnt_match(device_t parent, cfdata_t cf, void *aux)
{
struct awinio_attach_args * const aio = aux;
const struct awin_locators * const loc = &aio->aio_loc;
if (strcmp(cf->cf_name, loc->loc_name))
return 0;
return 1;
}
static void
awin_cnt_attach(device_t parent, device_t self, void *aux)
{
struct awin_cnt_softc *sc = device_private(self);
struct awinio_attach_args * const aio = aux;
const struct awin_locators * const loc = &aio->aio_loc;
sc->sc_dev = self;
sc->sc_bst = aio->aio_core_bst;
mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_HIGH);
bus_space_subregion(sc->sc_bst, aio->aio_core_bsh,
loc->loc_offset, loc->loc_size, &sc->sc_bsh);
aprint_naive("\n");
aprint_normal("\n");
/* Set OSC24M clock source */
uint32_t ctrl = CNT_READ(sc, AWIN_CPUCFG_CNT64_CTRL_REG);
ctrl &= ~AWIN_CPUCFG_CNT64_CLK_SRC_SEL;
CNT_WRITE(sc, AWIN_CPUCFG_CNT64_CTRL_REG, ctrl);
sc->sc_tc.tc_get_timecount = awin_cnt_get_timecount;
sc->sc_tc.tc_poll_pps = NULL;
sc->sc_tc.tc_counter_mask = ~0;
sc->sc_tc.tc_frequency = AWIN_REF_FREQ;
sc->sc_tc.tc_name = "CNT64";
sc->sc_tc.tc_priv = sc;
sc->sc_tc.tc_quality = 200;
tc_init(&sc->sc_tc);
}
static u_int
awin_cnt_get_timecount(struct timecounter *tc)
{
struct awin_cnt_softc *sc = tc->tc_priv;
uint32_t ctrl;
u_int timecount;
mutex_enter(&sc->sc_lock);
/* Enable read latch, wait for it to clear */
ctrl = CNT_READ(sc, AWIN_CPUCFG_CNT64_CTRL_REG);
ctrl |= AWIN_CPUCFG_CNT64_RL_EN;
CNT_WRITE(sc, AWIN_CPUCFG_CNT64_CTRL_REG, ctrl);
do {
ctrl = CNT_READ(sc, AWIN_CPUCFG_CNT64_CTRL_REG);
} while (ctrl & AWIN_CPUCFG_CNT64_RL_EN);
timecount = CNT_READ(sc, AWIN_CPUCFG_CNT64_LOW_REG);
mutex_exit(&sc->sc_lock);
return timecount;
}