qemu-e2k/hw/rtc/aspeed_rtc.c

182 lines
4.4 KiB
C

/*
* ASPEED Real Time Clock
* Joel Stanley <joel@jms.id.au>
*
* Copyright 2019 IBM Corp
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "hw/rtc/aspeed_rtc.h"
#include "migration/vmstate.h"
#include "qemu/log.h"
#include "qemu/timer.h"
#include "trace.h"
#define COUNTER1 (0x00 / 4)
#define COUNTER2 (0x04 / 4)
#define ALARM (0x08 / 4)
#define CONTROL (0x10 / 4)
#define ALARM_STATUS (0x14 / 4)
#define RTC_UNLOCKED BIT(1)
#define RTC_ENABLED BIT(0)
static void aspeed_rtc_calc_offset(AspeedRtcState *rtc)
{
struct tm tm;
uint32_t year, cent;
uint32_t reg1 = rtc->reg[COUNTER1];
uint32_t reg2 = rtc->reg[COUNTER2];
tm.tm_mday = (reg1 >> 24) & 0x1f;
tm.tm_hour = (reg1 >> 16) & 0x1f;
tm.tm_min = (reg1 >> 8) & 0x3f;
tm.tm_sec = (reg1 >> 0) & 0x3f;
cent = (reg2 >> 16) & 0x1f;
year = (reg2 >> 8) & 0x7f;
tm.tm_mon = ((reg2 >> 0) & 0x0f) - 1;
tm.tm_year = year + (cent * 100) - 1900;
rtc->offset = qemu_timedate_diff(&tm);
}
static uint32_t aspeed_rtc_get_counter(AspeedRtcState *rtc, int r)
{
uint32_t year, cent;
struct tm now;
qemu_get_timedate(&now, rtc->offset);
switch (r) {
case COUNTER1:
return (now.tm_mday << 24) | (now.tm_hour << 16) |
(now.tm_min << 8) | now.tm_sec;
case COUNTER2:
cent = (now.tm_year + 1900) / 100;
year = now.tm_year % 100;
return ((cent & 0x1f) << 16) | ((year & 0x7f) << 8) |
((now.tm_mon + 1) & 0xf);
default:
g_assert_not_reached();
}
}
static uint64_t aspeed_rtc_read(void *opaque, hwaddr addr,
unsigned size)
{
AspeedRtcState *rtc = opaque;
uint64_t val;
uint32_t r = addr >> 2;
switch (r) {
case COUNTER1:
case COUNTER2:
if (rtc->reg[CONTROL] & RTC_ENABLED) {
rtc->reg[r] = aspeed_rtc_get_counter(rtc, r);
}
/* fall through */
case CONTROL:
val = rtc->reg[r];
break;
case ALARM:
case ALARM_STATUS:
default:
qemu_log_mask(LOG_UNIMP, "%s: 0x%" HWADDR_PRIx "\n", __func__, addr);
return 0;
}
trace_aspeed_rtc_read(addr, val);
return val;
}
static void aspeed_rtc_write(void *opaque, hwaddr addr,
uint64_t val, unsigned size)
{
AspeedRtcState *rtc = opaque;
uint32_t r = addr >> 2;
switch (r) {
case COUNTER1:
case COUNTER2:
if (!(rtc->reg[CONTROL] & RTC_UNLOCKED)) {
break;
}
/* fall through */
case CONTROL:
rtc->reg[r] = val;
aspeed_rtc_calc_offset(rtc);
break;
case ALARM:
case ALARM_STATUS:
default:
qemu_log_mask(LOG_UNIMP, "%s: 0x%" HWADDR_PRIx "\n", __func__, addr);
break;
}
trace_aspeed_rtc_write(addr, val);
}
static void aspeed_rtc_reset(DeviceState *d)
{
AspeedRtcState *rtc = ASPEED_RTC(d);
rtc->offset = 0;
memset(rtc->reg, 0, sizeof(rtc->reg));
}
static const MemoryRegionOps aspeed_rtc_ops = {
.read = aspeed_rtc_read,
.write = aspeed_rtc_write,
.endianness = DEVICE_NATIVE_ENDIAN,
};
static const VMStateDescription vmstate_aspeed_rtc = {
.name = TYPE_ASPEED_RTC,
.version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_UINT32_ARRAY(reg, AspeedRtcState, 0x18),
VMSTATE_INT32(offset, AspeedRtcState),
VMSTATE_INT32(offset, AspeedRtcState),
VMSTATE_END_OF_LIST()
}
};
static void aspeed_rtc_realize(DeviceState *dev, Error **errp)
{
SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
AspeedRtcState *s = ASPEED_RTC(dev);
sysbus_init_irq(sbd, &s->irq);
memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_rtc_ops, s,
"aspeed-rtc", 0x18ULL);
sysbus_init_mmio(sbd, &s->iomem);
}
static void aspeed_rtc_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = aspeed_rtc_realize;
dc->vmsd = &vmstate_aspeed_rtc;
dc->reset = aspeed_rtc_reset;
}
static const TypeInfo aspeed_rtc_info = {
.name = TYPE_ASPEED_RTC,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(AspeedRtcState),
.class_init = aspeed_rtc_class_init,
};
static void aspeed_rtc_register_types(void)
{
type_register_static(&aspeed_rtc_info);
}
type_init(aspeed_rtc_register_types)