Philippe Mathieu-Daudé | 99c6413 | 2019-10-20 01:47:00 +0200 | [diff] [blame] | 1 | /* |
| 2 | * BCM2835 dummy thermal sensor |
| 3 | * |
| 4 | * Copyright (C) 2019 Philippe Mathieu-Daudé <f4bug@amsat.org> |
| 5 | * |
| 6 | * SPDX-License-Identifier: GPL-2.0-or-later |
| 7 | */ |
| 8 | |
| 9 | #include "qemu/osdep.h" |
| 10 | #include "qemu/log.h" |
| 11 | #include "qapi/error.h" |
| 12 | #include "hw/misc/bcm2835_thermal.h" |
| 13 | #include "hw/registerfields.h" |
| 14 | #include "migration/vmstate.h" |
| 15 | |
| 16 | REG32(CTL, 0) |
| 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) |
| 26 | |
| 27 | REG32(STAT, 4) |
| 28 | FIELD(STAT, DATA, 0, 10) |
| 29 | FIELD(STAT, VALID, 10, 1) |
| 30 | FIELD(STAT, INTERRUPT, 11, 1) |
| 31 | |
| 32 | #define THERMAL_OFFSET_C 412 |
| 33 | #define THERMAL_COEFF (-0.538f) |
| 34 | |
| 35 | static uint16_t bcm2835_thermal_temp2adc(int temp_C) |
| 36 | { |
| 37 | return (temp_C - THERMAL_OFFSET_C) / THERMAL_COEFF; |
| 38 | } |
| 39 | |
| 40 | static uint64_t bcm2835_thermal_read(void *opaque, hwaddr addr, unsigned size) |
| 41 | { |
| 42 | Bcm2835ThermalState *s = BCM2835_THERMAL(opaque); |
| 43 | uint32_t val = 0; |
| 44 | |
| 45 | switch (addr) { |
| 46 | case A_CTL: |
| 47 | val = s->ctl; |
| 48 | break; |
| 49 | case A_STAT: |
| 50 | /* Temperature is constantly 25°C. */ |
| 51 | val = FIELD_DP32(bcm2835_thermal_temp2adc(25), STAT, VALID, true); |
| 52 | break; |
| 53 | default: |
| 54 | /* MemoryRegionOps are aligned, so this can not happen. */ |
| 55 | g_assert_not_reached(); |
| 56 | } |
| 57 | return val; |
| 58 | } |
| 59 | |
| 60 | static void bcm2835_thermal_write(void *opaque, hwaddr addr, |
| 61 | uint64_t value, unsigned size) |
| 62 | { |
| 63 | Bcm2835ThermalState *s = BCM2835_THERMAL(opaque); |
| 64 | |
| 65 | switch (addr) { |
| 66 | case A_CTL: |
| 67 | s->ctl = value; |
| 68 | break; |
| 69 | case A_STAT: |
| 70 | qemu_log_mask(LOG_GUEST_ERROR, "%s: write 0x%" PRIx64 |
| 71 | " to 0x%" HWADDR_PRIx "\n", |
| 72 | __func__, value, addr); |
| 73 | break; |
| 74 | default: |
| 75 | /* MemoryRegionOps are aligned, so this can not happen. */ |
| 76 | g_assert_not_reached(); |
| 77 | } |
| 78 | } |
| 79 | |
| 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, |
| 86 | }; |
| 87 | |
| 88 | static void bcm2835_thermal_reset(DeviceState *dev) |
| 89 | { |
| 90 | Bcm2835ThermalState *s = BCM2835_THERMAL(dev); |
| 91 | |
| 92 | s->ctl = 0; |
| 93 | } |
| 94 | |
| 95 | static void bcm2835_thermal_realize(DeviceState *dev, Error **errp) |
| 96 | { |
| 97 | Bcm2835ThermalState *s = BCM2835_THERMAL(dev); |
| 98 | |
| 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); |
| 102 | } |
| 103 | |
| 104 | static const VMStateDescription bcm2835_thermal_vmstate = { |
| 105 | .name = "bcm2835_thermal", |
| 106 | .version_id = 1, |
| 107 | .minimum_version_id = 1, |
| 108 | .fields = (VMStateField[]) { |
| 109 | VMSTATE_UINT32(ctl, Bcm2835ThermalState), |
| 110 | VMSTATE_END_OF_LIST() |
| 111 | } |
| 112 | }; |
| 113 | |
| 114 | static void bcm2835_thermal_class_init(ObjectClass *klass, void *data) |
| 115 | { |
| 116 | DeviceClass *dc = DEVICE_CLASS(klass); |
| 117 | |
| 118 | dc->realize = bcm2835_thermal_realize; |
| 119 | dc->reset = bcm2835_thermal_reset; |
| 120 | dc->vmsd = &bcm2835_thermal_vmstate; |
| 121 | } |
| 122 | |
| 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, |
| 128 | }; |
| 129 | |
| 130 | static void bcm2835_thermal_register_types(void) |
| 131 | { |
| 132 | type_register_static(&bcm2835_thermal_info); |
| 133 | } |
| 134 | |
| 135 | type_init(bcm2835_thermal_register_types) |