Archipelago » qemu

/*

 * TI OMAP2 32kHz sync timer emulation.

 *

 * Copyright (C) 2007-2008 Nokia Corporation

 * Written by Andrzej Zaborowski <andrew@openedhand.com>

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License as

 * published by the Free Software Foundation; either version 2 or

 * (at your option) any later version of the License.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License along

 * with this program; if not, see <http://www.gnu.org/licenses/>.

 */

#include "hw/hw.h"

#include "qemu/timer.h"

#include "hw/arm/omap.h"

struct omap_synctimer_s {

    MemoryRegion iomem;

    uint32_t val;

    uint16_t readh;

};

/* 32-kHz Sync Timer of the OMAP2 */

static uint32_t omap_synctimer_read(struct omap_synctimer_s *s) {

    return muldiv64(qemu_get_clock_ns(vm_clock), 0x8000, get_ticks_per_sec());

}

void omap_synctimer_reset(struct omap_synctimer_s *s)

{

    s->val = omap_synctimer_read(s);

}

static uint32_t omap_synctimer_readw(void *opaque, hwaddr addr)

{

    struct omap_synctimer_s *s = (struct omap_synctimer_s *) opaque;

    switch (addr) {

    case 0x00:        /* 32KSYNCNT_REV */

        return 0x21;

    case 0x10:        /* CR */

        return omap_synctimer_read(s) - s->val;

    }

    OMAP_BAD_REG(addr);

    return 0;

}

static uint32_t omap_synctimer_readh(void *opaque, hwaddr addr)

{

    struct omap_synctimer_s *s = (struct omap_synctimer_s *) opaque;

    uint32_t ret;

    if (addr & 2)

        return s->readh;

    else {

        ret = omap_synctimer_readw(opaque, addr);

        s->readh = ret >> 16;

        return ret & 0xffff;

    }

}

static void omap_synctimer_write(void *opaque, hwaddr addr,

                uint32_t value)

{

    OMAP_BAD_REG(addr);

}

static const MemoryRegionOps omap_synctimer_ops = {

    .old_mmio = {

        .read = {

            omap_badwidth_read32,

            omap_synctimer_readh,

            omap_synctimer_readw,

        },

        .write = {

            omap_badwidth_write32,

            omap_synctimer_write,

            omap_synctimer_write,

        },

    },

    .endianness = DEVICE_NATIVE_ENDIAN,

};

struct omap_synctimer_s *omap_synctimer_init(struct omap_target_agent_s *ta,

                struct omap_mpu_state_s *mpu, omap_clk fclk, omap_clk iclk)

{

    struct omap_synctimer_s *s = g_malloc0(sizeof(*s));

    omap_synctimer_reset(s);

    memory_region_init_io(&s->iomem, &omap_synctimer_ops, s, "omap.synctimer",

                          omap_l4_region_size(ta, 0));

    omap_l4_attach(ta, 0, &s->iomem);

    return s;

}