qemu-e2k/hw/rtc/m48t59.c
Peter Maydell 7038b6e4e7 hw/rtc/m48t59: Use 64-bit arithmetic in set_alarm()
In the m48t59 device we almost always use 64-bit arithmetic when
dealing with time_t deltas.  The one exception is in set_alarm(),
which currently uses a plain 'int' to hold the difference between two
time_t values.  Switch to int64_t instead to avoid any possible
overflow issues.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-08-31 09:45:17 +01:00

687 lines
18 KiB
C

/*
* QEMU M48T59 and M48T08 NVRAM emulation for PPC PREP and Sparc platforms
*
* Copyright (c) 2003-2005, 2007, 2017 Jocelyn Mayer
* Copyright (c) 2013 Hervé Poussineau
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "hw/irq.h"
#include "hw/qdev-properties.h"
#include "hw/rtc/m48t59.h"
#include "qemu/timer.h"
#include "sysemu/runstate.h"
#include "sysemu/rtc.h"
#include "sysemu/sysemu.h"
#include "hw/sysbus.h"
#include "qapi/error.h"
#include "qemu/bcd.h"
#include "qemu/module.h"
#include "trace.h"
#include "m48t59-internal.h"
#include "migration/vmstate.h"
#include "qom/object.h"
#define TYPE_M48TXX_SYS_BUS "sysbus-m48txx"
typedef struct M48txxSysBusDeviceClass M48txxSysBusDeviceClass;
typedef struct M48txxSysBusState M48txxSysBusState;
DECLARE_OBJ_CHECKERS(M48txxSysBusState, M48txxSysBusDeviceClass,
M48TXX_SYS_BUS, TYPE_M48TXX_SYS_BUS)
/*
* Chipset docs:
* http://www.st.com/stonline/products/literature/ds/2410/m48t02.pdf
* http://www.st.com/stonline/products/literature/ds/2411/m48t08.pdf
* http://www.st.com/stonline/products/literature/od/7001/m48t59y.pdf
*/
struct M48txxSysBusState {
SysBusDevice parent_obj;
M48t59State state;
MemoryRegion io;
};
struct M48txxSysBusDeviceClass {
SysBusDeviceClass parent_class;
M48txxInfo info;
};
static M48txxInfo m48txx_sysbus_info[] = {
{
.bus_name = "sysbus-m48t02",
.model = 2,
.size = 0x800,
},{
.bus_name = "sysbus-m48t08",
.model = 8,
.size = 0x2000,
},{
.bus_name = "sysbus-m48t59",
.model = 59,
.size = 0x2000,
}
};
/* Fake timer functions */
/* Alarm management */
static void alarm_cb (void *opaque)
{
struct tm tm;
uint64_t next_time;
M48t59State *NVRAM = opaque;
qemu_set_irq(NVRAM->IRQ, 1);
if ((NVRAM->buffer[0x1FF5] & 0x80) == 0 &&
(NVRAM->buffer[0x1FF4] & 0x80) == 0 &&
(NVRAM->buffer[0x1FF3] & 0x80) == 0 &&
(NVRAM->buffer[0x1FF2] & 0x80) == 0) {
/* Repeat once a month */
qemu_get_timedate(&tm, NVRAM->time_offset);
tm.tm_mon++;
if (tm.tm_mon == 13) {
tm.tm_mon = 1;
tm.tm_year++;
}
next_time = qemu_timedate_diff(&tm) - NVRAM->time_offset;
} else if ((NVRAM->buffer[0x1FF5] & 0x80) != 0 &&
(NVRAM->buffer[0x1FF4] & 0x80) == 0 &&
(NVRAM->buffer[0x1FF3] & 0x80) == 0 &&
(NVRAM->buffer[0x1FF2] & 0x80) == 0) {
/* Repeat once a day */
next_time = 24 * 60 * 60;
} else if ((NVRAM->buffer[0x1FF5] & 0x80) != 0 &&
(NVRAM->buffer[0x1FF4] & 0x80) != 0 &&
(NVRAM->buffer[0x1FF3] & 0x80) == 0 &&
(NVRAM->buffer[0x1FF2] & 0x80) == 0) {
/* Repeat once an hour */
next_time = 60 * 60;
} else if ((NVRAM->buffer[0x1FF5] & 0x80) != 0 &&
(NVRAM->buffer[0x1FF4] & 0x80) != 0 &&
(NVRAM->buffer[0x1FF3] & 0x80) != 0 &&
(NVRAM->buffer[0x1FF2] & 0x80) == 0) {
/* Repeat once a minute */
next_time = 60;
} else {
/* Repeat once a second */
next_time = 1;
}
timer_mod(NVRAM->alrm_timer, qemu_clock_get_ns(rtc_clock) +
next_time * 1000);
qemu_set_irq(NVRAM->IRQ, 0);
}
static void set_alarm(M48t59State *NVRAM)
{
int64_t diff;
if (NVRAM->alrm_timer != NULL) {
timer_del(NVRAM->alrm_timer);
diff = qemu_timedate_diff(&NVRAM->alarm) - NVRAM->time_offset;
if (diff > 0)
timer_mod(NVRAM->alrm_timer, diff * 1000);
}
}
/* RTC management helpers */
static inline void get_time(M48t59State *NVRAM, struct tm *tm)
{
qemu_get_timedate(tm, NVRAM->time_offset);
}
static void set_time(M48t59State *NVRAM, struct tm *tm)
{
NVRAM->time_offset = qemu_timedate_diff(tm);
set_alarm(NVRAM);
}
/* Watchdog management */
static void watchdog_cb (void *opaque)
{
M48t59State *NVRAM = opaque;
NVRAM->buffer[0x1FF0] |= 0x80;
if (NVRAM->buffer[0x1FF7] & 0x80) {
NVRAM->buffer[0x1FF7] = 0x00;
NVRAM->buffer[0x1FFC] &= ~0x40;
/* May it be a hw CPU Reset instead ? */
qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
} else {
qemu_set_irq(NVRAM->IRQ, 1);
qemu_set_irq(NVRAM->IRQ, 0);
}
}
static void set_up_watchdog(M48t59State *NVRAM, uint8_t value)
{
uint64_t interval; /* in 1/16 seconds */
NVRAM->buffer[0x1FF0] &= ~0x80;
if (NVRAM->wd_timer != NULL) {
timer_del(NVRAM->wd_timer);
if (value != 0) {
interval = (1 << (2 * (value & 0x03))) * ((value >> 2) & 0x1F);
timer_mod(NVRAM->wd_timer, ((uint64_t)time(NULL) * 1000) +
((interval * 1000) >> 4));
}
}
}
/* Direct access to NVRAM */
void m48t59_write(M48t59State *NVRAM, uint32_t addr, uint32_t val)
{
struct tm tm;
int tmp;
trace_m48txx_nvram_mem_write(addr, val);
/* check for NVRAM access */
if ((NVRAM->model == 2 && addr < 0x7f8) ||
(NVRAM->model == 8 && addr < 0x1ff8) ||
(NVRAM->model == 59 && addr < 0x1ff0)) {
goto do_write;
}
/* TOD access */
switch (addr) {
case 0x1FF0:
/* flags register : read-only */
break;
case 0x1FF1:
/* unused */
break;
case 0x1FF2:
/* alarm seconds */
tmp = from_bcd(val & 0x7F);
if (tmp >= 0 && tmp <= 59) {
NVRAM->alarm.tm_sec = tmp;
NVRAM->buffer[0x1FF2] = val;
set_alarm(NVRAM);
}
break;
case 0x1FF3:
/* alarm minutes */
tmp = from_bcd(val & 0x7F);
if (tmp >= 0 && tmp <= 59) {
NVRAM->alarm.tm_min = tmp;
NVRAM->buffer[0x1FF3] = val;
set_alarm(NVRAM);
}
break;
case 0x1FF4:
/* alarm hours */
tmp = from_bcd(val & 0x3F);
if (tmp >= 0 && tmp <= 23) {
NVRAM->alarm.tm_hour = tmp;
NVRAM->buffer[0x1FF4] = val;
set_alarm(NVRAM);
}
break;
case 0x1FF5:
/* alarm date */
tmp = from_bcd(val & 0x3F);
if (tmp != 0) {
NVRAM->alarm.tm_mday = tmp;
NVRAM->buffer[0x1FF5] = val;
set_alarm(NVRAM);
}
break;
case 0x1FF6:
/* interrupts */
NVRAM->buffer[0x1FF6] = val;
break;
case 0x1FF7:
/* watchdog */
NVRAM->buffer[0x1FF7] = val;
set_up_watchdog(NVRAM, val);
break;
case 0x1FF8:
case 0x07F8:
/* control */
NVRAM->buffer[addr] = (val & ~0xA0) | 0x90;
break;
case 0x1FF9:
case 0x07F9:
/* seconds (BCD) */
tmp = from_bcd(val & 0x7F);
if (tmp >= 0 && tmp <= 59) {
get_time(NVRAM, &tm);
tm.tm_sec = tmp;
set_time(NVRAM, &tm);
}
if ((val & 0x80) ^ (NVRAM->buffer[addr] & 0x80)) {
if (val & 0x80) {
NVRAM->stop_time = time(NULL);
} else {
NVRAM->time_offset += NVRAM->stop_time - time(NULL);
NVRAM->stop_time = 0;
}
}
NVRAM->buffer[addr] = val & 0x80;
break;
case 0x1FFA:
case 0x07FA:
/* minutes (BCD) */
tmp = from_bcd(val & 0x7F);
if (tmp >= 0 && tmp <= 59) {
get_time(NVRAM, &tm);
tm.tm_min = tmp;
set_time(NVRAM, &tm);
}
break;
case 0x1FFB:
case 0x07FB:
/* hours (BCD) */
tmp = from_bcd(val & 0x3F);
if (tmp >= 0 && tmp <= 23) {
get_time(NVRAM, &tm);
tm.tm_hour = tmp;
set_time(NVRAM, &tm);
}
break;
case 0x1FFC:
case 0x07FC:
/* day of the week / century */
tmp = from_bcd(val & 0x07);
get_time(NVRAM, &tm);
tm.tm_wday = tmp;
set_time(NVRAM, &tm);
NVRAM->buffer[addr] = val & 0x40;
break;
case 0x1FFD:
case 0x07FD:
/* date (BCD) */
tmp = from_bcd(val & 0x3F);
if (tmp != 0) {
get_time(NVRAM, &tm);
tm.tm_mday = tmp;
set_time(NVRAM, &tm);
}
break;
case 0x1FFE:
case 0x07FE:
/* month */
tmp = from_bcd(val & 0x1F);
if (tmp >= 1 && tmp <= 12) {
get_time(NVRAM, &tm);
tm.tm_mon = tmp - 1;
set_time(NVRAM, &tm);
}
break;
case 0x1FFF:
case 0x07FF:
/* year */
tmp = from_bcd(val);
if (tmp >= 0 && tmp <= 99) {
get_time(NVRAM, &tm);
tm.tm_year = from_bcd(val) + NVRAM->base_year - 1900;
set_time(NVRAM, &tm);
}
break;
default:
/* Check lock registers state */
if (addr >= 0x20 && addr <= 0x2F && (NVRAM->lock & 1))
break;
if (addr >= 0x30 && addr <= 0x3F && (NVRAM->lock & 2))
break;
do_write:
if (addr < NVRAM->size) {
NVRAM->buffer[addr] = val & 0xFF;
}
break;
}
}
uint32_t m48t59_read(M48t59State *NVRAM, uint32_t addr)
{
struct tm tm;
uint32_t retval = 0xFF;
/* check for NVRAM access */
if ((NVRAM->model == 2 && addr < 0x078f) ||
(NVRAM->model == 8 && addr < 0x1ff8) ||
(NVRAM->model == 59 && addr < 0x1ff0)) {
goto do_read;
}
/* TOD access */
switch (addr) {
case 0x1FF0:
/* flags register */
goto do_read;
case 0x1FF1:
/* unused */
retval = 0;
break;
case 0x1FF2:
/* alarm seconds */
goto do_read;
case 0x1FF3:
/* alarm minutes */
goto do_read;
case 0x1FF4:
/* alarm hours */
goto do_read;
case 0x1FF5:
/* alarm date */
goto do_read;
case 0x1FF6:
/* interrupts */
goto do_read;
case 0x1FF7:
/* A read resets the watchdog */
set_up_watchdog(NVRAM, NVRAM->buffer[0x1FF7]);
goto do_read;
case 0x1FF8:
case 0x07F8:
/* control */
goto do_read;
case 0x1FF9:
case 0x07F9:
/* seconds (BCD) */
get_time(NVRAM, &tm);
retval = (NVRAM->buffer[addr] & 0x80) | to_bcd(tm.tm_sec);
break;
case 0x1FFA:
case 0x07FA:
/* minutes (BCD) */
get_time(NVRAM, &tm);
retval = to_bcd(tm.tm_min);
break;
case 0x1FFB:
case 0x07FB:
/* hours (BCD) */
get_time(NVRAM, &tm);
retval = to_bcd(tm.tm_hour);
break;
case 0x1FFC:
case 0x07FC:
/* day of the week / century */
get_time(NVRAM, &tm);
retval = NVRAM->buffer[addr] | tm.tm_wday;
break;
case 0x1FFD:
case 0x07FD:
/* date */
get_time(NVRAM, &tm);
retval = to_bcd(tm.tm_mday);
break;
case 0x1FFE:
case 0x07FE:
/* month */
get_time(NVRAM, &tm);
retval = to_bcd(tm.tm_mon + 1);
break;
case 0x1FFF:
case 0x07FF:
/* year */
get_time(NVRAM, &tm);
retval = to_bcd((tm.tm_year + 1900 - NVRAM->base_year) % 100);
break;
default:
/* Check lock registers state */
if (addr >= 0x20 && addr <= 0x2F && (NVRAM->lock & 1))
break;
if (addr >= 0x30 && addr <= 0x3F && (NVRAM->lock & 2))
break;
do_read:
if (addr < NVRAM->size) {
retval = NVRAM->buffer[addr];
}
break;
}
trace_m48txx_nvram_mem_read(addr, retval);
return retval;
}
/* IO access to NVRAM */
static void NVRAM_writeb(void *opaque, hwaddr addr, uint64_t val,
unsigned size)
{
M48t59State *NVRAM = opaque;
trace_m48txx_nvram_io_write(addr, val);
switch (addr) {
case 0:
NVRAM->addr &= ~0x00FF;
NVRAM->addr |= val;
break;
case 1:
NVRAM->addr &= ~0xFF00;
NVRAM->addr |= val << 8;
break;
case 3:
m48t59_write(NVRAM, NVRAM->addr, val);
NVRAM->addr = 0x0000;
break;
default:
break;
}
}
static uint64_t NVRAM_readb(void *opaque, hwaddr addr, unsigned size)
{
M48t59State *NVRAM = opaque;
uint32_t retval;
switch (addr) {
case 3:
retval = m48t59_read(NVRAM, NVRAM->addr);
break;
default:
retval = -1;
break;
}
trace_m48txx_nvram_io_read(addr, retval);
return retval;
}
static uint64_t nvram_read(void *opaque, hwaddr addr, unsigned size)
{
M48t59State *NVRAM = opaque;
return m48t59_read(NVRAM, addr);
}
static void nvram_write(void *opaque, hwaddr addr, uint64_t value,
unsigned size)
{
M48t59State *NVRAM = opaque;
return m48t59_write(NVRAM, addr, value);
}
static const MemoryRegionOps nvram_ops = {
.read = nvram_read,
.write = nvram_write,
.impl.min_access_size = 1,
.impl.max_access_size = 1,
.valid.min_access_size = 1,
.valid.max_access_size = 4,
.endianness = DEVICE_BIG_ENDIAN,
};
static const VMStateDescription vmstate_m48t59 = {
.name = "m48t59",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_UINT8(lock, M48t59State),
VMSTATE_UINT16(addr, M48t59State),
VMSTATE_VBUFFER_UINT32(buffer, M48t59State, 0, NULL, size),
VMSTATE_END_OF_LIST()
}
};
void m48t59_reset_common(M48t59State *NVRAM)
{
NVRAM->addr = 0;
NVRAM->lock = 0;
if (NVRAM->alrm_timer != NULL)
timer_del(NVRAM->alrm_timer);
if (NVRAM->wd_timer != NULL)
timer_del(NVRAM->wd_timer);
}
static void m48t59_reset_sysbus(DeviceState *d)
{
M48txxSysBusState *sys = M48TXX_SYS_BUS(d);
M48t59State *NVRAM = &sys->state;
m48t59_reset_common(NVRAM);
}
const MemoryRegionOps m48t59_io_ops = {
.read = NVRAM_readb,
.write = NVRAM_writeb,
.impl = {
.min_access_size = 1,
.max_access_size = 1,
},
.endianness = DEVICE_LITTLE_ENDIAN,
};
void m48t59_realize_common(M48t59State *s, Error **errp)
{
s->buffer = g_malloc0(s->size);
if (s->model == 59) {
s->alrm_timer = timer_new_ns(rtc_clock, &alarm_cb, s);
s->wd_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, &watchdog_cb, s);
}
qemu_get_timedate(&s->alarm, 0);
}
static void m48t59_init1(Object *obj)
{
M48txxSysBusDeviceClass *u = M48TXX_SYS_BUS_GET_CLASS(obj);
M48txxSysBusState *d = M48TXX_SYS_BUS(obj);
SysBusDevice *dev = SYS_BUS_DEVICE(obj);
M48t59State *s = &d->state;
s->model = u->info.model;
s->size = u->info.size;
sysbus_init_irq(dev, &s->IRQ);
memory_region_init_io(&s->iomem, obj, &nvram_ops, s, "m48t59.nvram",
s->size);
memory_region_init_io(&d->io, obj, &m48t59_io_ops, s, "m48t59", 4);
}
static void m48t59_realize(DeviceState *dev, Error **errp)
{
M48txxSysBusState *d = M48TXX_SYS_BUS(dev);
M48t59State *s = &d->state;
SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
sysbus_init_mmio(sbd, &s->iomem);
sysbus_init_mmio(sbd, &d->io);
m48t59_realize_common(s, errp);
}
static uint32_t m48txx_sysbus_read(Nvram *obj, uint32_t addr)
{
M48txxSysBusState *d = M48TXX_SYS_BUS(obj);
return m48t59_read(&d->state, addr);
}
static void m48txx_sysbus_write(Nvram *obj, uint32_t addr, uint32_t val)
{
M48txxSysBusState *d = M48TXX_SYS_BUS(obj);
m48t59_write(&d->state, addr, val);
}
static void m48txx_sysbus_toggle_lock(Nvram *obj, int lock)
{
M48txxSysBusState *d = M48TXX_SYS_BUS(obj);
m48t59_toggle_lock(&d->state, lock);
}
static Property m48t59_sysbus_properties[] = {
DEFINE_PROP_INT32("base-year", M48txxSysBusState, state.base_year, 0),
DEFINE_PROP_END_OF_LIST(),
};
static void m48txx_sysbus_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
NvramClass *nc = NVRAM_CLASS(klass);
dc->realize = m48t59_realize;
dc->reset = m48t59_reset_sysbus;
device_class_set_props(dc, m48t59_sysbus_properties);
dc->vmsd = &vmstate_m48t59;
nc->read = m48txx_sysbus_read;
nc->write = m48txx_sysbus_write;
nc->toggle_lock = m48txx_sysbus_toggle_lock;
}
static void m48txx_sysbus_concrete_class_init(ObjectClass *klass, void *data)
{
M48txxSysBusDeviceClass *u = M48TXX_SYS_BUS_CLASS(klass);
M48txxInfo *info = data;
u->info = *info;
}
static const TypeInfo nvram_info = {
.name = TYPE_NVRAM,
.parent = TYPE_INTERFACE,
.class_size = sizeof(NvramClass),
};
static const TypeInfo m48txx_sysbus_type_info = {
.name = TYPE_M48TXX_SYS_BUS,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(M48txxSysBusState),
.instance_init = m48t59_init1,
.abstract = true,
.class_init = m48txx_sysbus_class_init,
.interfaces = (InterfaceInfo[]) {
{ TYPE_NVRAM },
{ }
}
};
static void m48t59_register_types(void)
{
TypeInfo sysbus_type_info = {
.parent = TYPE_M48TXX_SYS_BUS,
.class_size = sizeof(M48txxSysBusDeviceClass),
.class_init = m48txx_sysbus_concrete_class_init,
};
int i;
type_register_static(&nvram_info);
type_register_static(&m48txx_sysbus_type_info);
for (i = 0; i < ARRAY_SIZE(m48txx_sysbus_info); i++) {
sysbus_type_info.name = m48txx_sysbus_info[i].bus_name;
sysbus_type_info.class_data = &m48txx_sysbus_info[i];
type_register(&sysbus_type_info);
}
}
type_init(m48t59_register_types)