| 1 | /* |
| 2 | * M41T80 serial rtc emulation |
| 3 | * |
| 4 | * Copyright (c) 2018 BALATON Zoltan |
| 5 | * |
| 6 | * This work is licensed under the GNU GPL license version 2 or later. |
| 7 | * |
| 8 | */ |
| 9 | |
| 10 | #include "qemu/osdep.h" |
| 11 | #include "qemu/log.h" |
| 12 | #include "qemu/module.h" |
| 13 | #include "qemu/timer.h" |
| 14 | #include "qemu/bcd.h" |
| 15 | #include "hw/i2c/i2c.h" |
| 16 | #include "qom/object.h" |
| 17 | #include "system/rtc.h" |
| 18 | |
| 19 | #define TYPE_M41T80 "m41t80" |
| 20 | OBJECT_DECLARE_SIMPLE_TYPE(M41t80State, M41T80) |
| 21 | |
| 22 | struct M41t80State { |
| 23 | I2CSlave parent_obj; |
| 24 | int8_t addr; |
| 25 | }; |
| 26 | |
| 27 | static void m41t80_realize(DeviceState *dev, Error **errp) |
| 28 | { |
| 29 | M41t80State *s = M41T80(dev); |
| 30 | |
| 31 | s->addr = -1; |
| 32 | } |
| 33 | |
| 34 | static int m41t80_send(I2CSlave *i2c, uint8_t data) |
| 35 | { |
| 36 | M41t80State *s = M41T80(i2c); |
| 37 | |
| 38 | if (s->addr < 0) { |
| 39 | s->addr = data; |
| 40 | } else { |
| 41 | s->addr++; |
| 42 | } |
| 43 | return 0; |
| 44 | } |
| 45 | |
| 46 | static uint8_t m41t80_recv(I2CSlave *i2c) |
| 47 | { |
| 48 | M41t80State *s = M41T80(i2c); |
| 49 | struct tm now; |
| 50 | int64_t rt; |
| 51 | |
| 52 | if (s->addr < 0) { |
| 53 | s->addr = 0; |
| 54 | } |
| 55 | if (s->addr >= 1 && s->addr <= 7) { |
| 56 | qemu_get_timedate(&now, -1); |
| 57 | } |
| 58 | switch (s->addr++) { |
| 59 | case 0: |
| 60 | rt = g_get_real_time(); |
| 61 | return to_bcd((rt % G_USEC_PER_SEC) / 10000); |
| 62 | case 1: |
| 63 | return to_bcd(now.tm_sec); |
| 64 | case 2: |
| 65 | return to_bcd(now.tm_min); |
| 66 | case 3: |
| 67 | return to_bcd(now.tm_hour); |
| 68 | case 4: |
| 69 | return to_bcd(now.tm_wday); |
| 70 | case 5: |
| 71 | return to_bcd(now.tm_mday); |
| 72 | case 6: |
| 73 | return to_bcd(now.tm_mon + 1); |
| 74 | case 7: |
| 75 | return to_bcd(now.tm_year % 100); |
| 76 | case 8 ... 19: |
| 77 | qemu_log_mask(LOG_UNIMP, "%s: unimplemented register: %d\n", |
| 78 | __func__, s->addr - 1); |
| 79 | return 0; |
| 80 | default: |
| 81 | qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid register: %d\n", |
| 82 | __func__, s->addr - 1); |
| 83 | return 0; |
| 84 | } |
| 85 | } |
| 86 | |
| 87 | static int m41t80_event(I2CSlave *i2c, enum i2c_event event) |
| 88 | { |
| 89 | M41t80State *s = M41T80(i2c); |
| 90 | |
| 91 | if (event == I2C_START_SEND) { |
| 92 | s->addr = -1; |
| 93 | } |
| 94 | return 0; |
| 95 | } |
| 96 | |
| 97 | static void m41t80_class_init(ObjectClass *klass, const void *data) |
| 98 | { |
| 99 | DeviceClass *dc = DEVICE_CLASS(klass); |
| 100 | I2CSlaveClass *sc = I2C_SLAVE_CLASS(klass); |
| 101 | |
| 102 | dc->realize = m41t80_realize; |
| 103 | sc->send = m41t80_send; |
| 104 | sc->recv = m41t80_recv; |
| 105 | sc->event = m41t80_event; |
| 106 | } |
| 107 | |
| 108 | static const TypeInfo m41t80_info = { |
| 109 | .name = TYPE_M41T80, |
| 110 | .parent = TYPE_I2C_SLAVE, |
| 111 | .instance_size = sizeof(M41t80State), |
| 112 | .class_init = m41t80_class_init, |
| 113 | }; |
| 114 | |
| 115 | static void m41t80_register_types(void) |
| 116 | { |
| 117 | type_register_static(&m41t80_info); |
| 118 | } |
| 119 | |
| 120 | type_init(m41t80_register_types) |