2 * BCM2835 dummy thermal sensor
4 * Copyright (C) 2019 Philippe Mathieu-Daudé <f4bug@amsat.org>
6 * SPDX-License-Identifier: GPL-2.0-or-later
9 #include "qemu/osdep.h"
11 #include "qapi/error.h"
12 #include "hw/misc/bcm2835_thermal.h"
13 #include "hw/registerfields.h"
14 #include "migration/vmstate.h"
17 FIELD(CTL, POWER_DOWN, 0, 1)
18 FIELD(CTL, RESET, 1, 1)
19 FIELD(CTL, BANDGAP_CTRL, 2, 3)
20 FIELD(CTL, INTERRUPT_ENABLE, 5, 1)
21 FIELD(CTL, DIRECT, 6, 1)
22 FIELD(CTL, INTERRUPT_CLEAR, 7, 1)
23 FIELD(CTL, HOLD, 8, 10)
24 FIELD(CTL, RESET_DELAY, 18, 8)
25 FIELD(CTL, REGULATOR_ENABLE, 26, 1)
28 FIELD(STAT, DATA, 0, 10)
29 FIELD(STAT, VALID, 10, 1)
30 FIELD(STAT, INTERRUPT, 11, 1)
32 #define THERMAL_OFFSET_C 412
33 #define THERMAL_COEFF (-0.538f)
35 static uint16_t bcm2835_thermal_temp2adc(int temp_C)
37 return (temp_C - THERMAL_OFFSET_C) / THERMAL_COEFF;
40 static uint64_t bcm2835_thermal_read(void *opaque, hwaddr addr, unsigned size)
42 Bcm2835ThermalState *s = BCM2835_THERMAL(opaque);
50 /* Temperature is constantly 25°C. */
51 val = FIELD_DP32(bcm2835_thermal_temp2adc(25), STAT, VALID, true);
54 /* MemoryRegionOps are aligned, so this can not happen. */
55 g_assert_not_reached();
60 static void bcm2835_thermal_write(void *opaque, hwaddr addr,
61 uint64_t value, unsigned size)
63 Bcm2835ThermalState *s = BCM2835_THERMAL(opaque);
70 qemu_log_mask(LOG_GUEST_ERROR, "%s: write 0x%" PRIx64
71 " to 0x%" HWADDR_PRIx "\n",
72 __func__, value, addr);
75 /* MemoryRegionOps are aligned, so this can not happen. */
76 g_assert_not_reached();
80 static const MemoryRegionOps bcm2835_thermal_ops = {
81 .read = bcm2835_thermal_read,
82 .write = bcm2835_thermal_write,
83 .impl.max_access_size = 4,
84 .valid.min_access_size = 4,
85 .endianness = DEVICE_NATIVE_ENDIAN,
88 static void bcm2835_thermal_reset(DeviceState *dev)
90 Bcm2835ThermalState *s = BCM2835_THERMAL(dev);
95 static void bcm2835_thermal_realize(DeviceState *dev, Error **errp)
97 Bcm2835ThermalState *s = BCM2835_THERMAL(dev);
99 memory_region_init_io(&s->iomem, OBJECT(s), &bcm2835_thermal_ops,
100 s, TYPE_BCM2835_THERMAL, 8);
101 sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
104 static const VMStateDescription bcm2835_thermal_vmstate = {
105 .name = "bcm2835_thermal",
107 .minimum_version_id = 1,
108 .fields = (VMStateField[]) {
109 VMSTATE_UINT32(ctl, Bcm2835ThermalState),
110 VMSTATE_END_OF_LIST()
114 static void bcm2835_thermal_class_init(ObjectClass *klass, void *data)
116 DeviceClass *dc = DEVICE_CLASS(klass);
118 dc->realize = bcm2835_thermal_realize;
119 dc->reset = bcm2835_thermal_reset;
120 dc->vmsd = &bcm2835_thermal_vmstate;
123 static const TypeInfo bcm2835_thermal_info = {
124 .name = TYPE_BCM2835_THERMAL,
125 .parent = TYPE_SYS_BUS_DEVICE,
126 .instance_size = sizeof(Bcm2835ThermalState),
127 .class_init = bcm2835_thermal_class_init,
130 static void bcm2835_thermal_register_types(void)
132 type_register_static(&bcm2835_thermal_info);
135 type_init(bcm2835_thermal_register_types)