qemu-e2k/hw/omap_synctimer.c

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/*
* 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.h"
#include "qemu-timer.h"
#include "omap.h"
struct omap_synctimer_s {
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, target_phys_addr_t 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, target_phys_addr_t 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 CPUReadMemoryFunc * const omap_synctimer_readfn[] = {
omap_badwidth_read32,
omap_synctimer_readh,
omap_synctimer_readw,
};
static void omap_synctimer_write(void *opaque, target_phys_addr_t addr,
uint32_t value)
{
OMAP_BAD_REG(addr);
}
static CPUWriteMemoryFunc * const omap_synctimer_writefn[] = {
omap_badwidth_write32,
omap_synctimer_write,
omap_synctimer_write,
};
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);
omap_l4_attach(ta, 0, l4_register_io_memory(
omap_synctimer_readfn, omap_synctimer_writefn, s));
return s;
}