blob: 1649da866899b075460f9fd5eb529422b40e53fb [file] [log] [blame]
/*
* BCM2835 Power Management emulation
*
* Copyright (C) 2017 Marcin Chojnacki <marcinch7@gmail.com>
* Copyright (C) 2021 Nolan Leake <nolan@sigbus.net>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "qemu/log.h"
#include "qemu/module.h"
#include "hw/misc/bcm2835_powermgt.h"
#include "migration/vmstate.h"
#include "sysemu/runstate.h"
#define PASSWORD 0x5a000000
#define PASSWORD_MASK 0xff000000
#define R_RSTC 0x1c
#define V_RSTC_RESET 0x20
#define R_RSTS 0x20
#define V_RSTS_POWEROFF 0x555 /* Linux uses partition 63 to indicate halt. */
#define R_WDOG 0x24
static uint64_t bcm2835_powermgt_read(void *opaque, hwaddr offset,
unsigned size)
{
BCM2835PowerMgtState *s = (BCM2835PowerMgtState *)opaque;
uint32_t res = 0;
switch (offset) {
case R_RSTC:
res = s->rstc;
break;
case R_RSTS:
res = s->rsts;
break;
case R_WDOG:
res = s->wdog;
break;
default:
qemu_log_mask(LOG_UNIMP,
"bcm2835_powermgt_read: Unknown offset 0x%08"HWADDR_PRIx
"\n", offset);
res = 0;
break;
}
return res;
}
static void bcm2835_powermgt_write(void *opaque, hwaddr offset,
uint64_t value, unsigned size)
{
BCM2835PowerMgtState *s = (BCM2835PowerMgtState *)opaque;
if ((value & PASSWORD_MASK) != PASSWORD) {
qemu_log_mask(LOG_GUEST_ERROR,
"bcm2835_powermgt_write: Bad password 0x%"PRIx64
" at offset 0x%08"HWADDR_PRIx"\n",
value, offset);
return;
}
value = value & ~PASSWORD_MASK;
switch (offset) {
case R_RSTC:
s->rstc = value;
if (value & V_RSTC_RESET) {
if ((s->rsts & 0xfff) == V_RSTS_POWEROFF) {
qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
} else {
qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
}
}
break;
case R_RSTS:
qemu_log_mask(LOG_UNIMP,
"bcm2835_powermgt_write: RSTS\n");
s->rsts = value;
break;
case R_WDOG:
qemu_log_mask(LOG_UNIMP,
"bcm2835_powermgt_write: WDOG\n");
s->wdog = value;
break;
default:
qemu_log_mask(LOG_UNIMP,
"bcm2835_powermgt_write: Unknown offset 0x%08"HWADDR_PRIx
"\n", offset);
break;
}
}
static const MemoryRegionOps bcm2835_powermgt_ops = {
.read = bcm2835_powermgt_read,
.write = bcm2835_powermgt_write,
.endianness = DEVICE_NATIVE_ENDIAN,
.impl.min_access_size = 4,
.impl.max_access_size = 4,
};
static const VMStateDescription vmstate_bcm2835_powermgt = {
.name = TYPE_BCM2835_POWERMGT,
.version_id = 1,
.minimum_version_id = 1,
.fields = (const VMStateField[]) {
VMSTATE_UINT32(rstc, BCM2835PowerMgtState),
VMSTATE_UINT32(rsts, BCM2835PowerMgtState),
VMSTATE_UINT32(wdog, BCM2835PowerMgtState),
VMSTATE_END_OF_LIST()
}
};
static void bcm2835_powermgt_init(Object *obj)
{
BCM2835PowerMgtState *s = BCM2835_POWERMGT(obj);
memory_region_init_io(&s->iomem, obj, &bcm2835_powermgt_ops, s,
TYPE_BCM2835_POWERMGT, 0x200);
sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
}
static void bcm2835_powermgt_reset(DeviceState *dev)
{
BCM2835PowerMgtState *s = BCM2835_POWERMGT(dev);
/* https://elinux.org/BCM2835_registers#PM */
s->rstc = 0x00000102;
s->rsts = 0x00001000;
s->wdog = 0x00000000;
}
static void bcm2835_powermgt_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->reset = bcm2835_powermgt_reset;
dc->vmsd = &vmstate_bcm2835_powermgt;
}
static const TypeInfo bcm2835_powermgt_info = {
.name = TYPE_BCM2835_POWERMGT,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(BCM2835PowerMgtState),
.class_init = bcm2835_powermgt_class_init,
.instance_init = bcm2835_powermgt_init,
};
static void bcm2835_powermgt_register_types(void)
{
type_register_static(&bcm2835_powermgt_info);
}
type_init(bcm2835_powermgt_register_types)