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-common.h" 12 #include "qemu/log.h" 13 #include "qemu/module.h" 14 #include "qemu/timer.h" 15 #include "qemu/bcd.h" 16 #include "hw/i2c/i2c.h" 17 #include "qom/object.h" 18 19 #define TYPE_M41T80 "m41t80" 20 typedef struct M41t80State M41t80State; 21 DECLARE_INSTANCE_CHECKER(M41t80State, M41T80, 22 TYPE_M41T80) 23 24 struct M41t80State { 25 I2CSlave parent_obj; 26 int8_t addr; 27 }; 28 29 static void m41t80_realize(DeviceState *dev, Error **errp) 30 { 31 M41t80State *s = M41T80(dev); 32 33 s->addr = -1; 34 } 35 36 static int m41t80_send(I2CSlave *i2c, uint8_t data) 37 { 38 M41t80State *s = M41T80(i2c); 39 40 if (s->addr < 0) { 41 s->addr = data; 42 } else { 43 s->addr++; 44 } 45 return 0; 46 } 47 48 static uint8_t m41t80_recv(I2CSlave *i2c) 49 { 50 M41t80State *s = M41T80(i2c); 51 struct tm now; 52 qemu_timeval tv; 53 54 if (s->addr < 0) { 55 s->addr = 0; 56 } 57 if (s->addr >= 1 && s->addr <= 7) { 58 qemu_get_timedate(&now, -1); 59 } 60 switch (s->addr++) { 61 case 0: 62 qemu_gettimeofday(&tv); 63 return to_bcd(tv.tv_usec / 10000); 64 case 1: 65 return to_bcd(now.tm_sec); 66 case 2: 67 return to_bcd(now.tm_min); 68 case 3: 69 return to_bcd(now.tm_hour); 70 case 4: 71 return to_bcd(now.tm_wday); 72 case 5: 73 return to_bcd(now.tm_mday); 74 case 6: 75 return to_bcd(now.tm_mon + 1); 76 case 7: 77 return to_bcd(now.tm_year % 100); 78 case 8 ... 19: 79 qemu_log_mask(LOG_UNIMP, "%s: unimplemented register: %d\n", 80 __func__, s->addr - 1); 81 return 0; 82 default: 83 qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid register: %d\n", 84 __func__, s->addr - 1); 85 return 0; 86 } 87 } 88 89 static int m41t80_event(I2CSlave *i2c, enum i2c_event event) 90 { 91 M41t80State *s = M41T80(i2c); 92 93 if (event == I2C_START_SEND) { 94 s->addr = -1; 95 } 96 return 0; 97 } 98 99 static void m41t80_class_init(ObjectClass *klass, void *data) 100 { 101 DeviceClass *dc = DEVICE_CLASS(klass); 102 I2CSlaveClass *sc = I2C_SLAVE_CLASS(klass); 103 104 dc->realize = m41t80_realize; 105 sc->send = m41t80_send; 106 sc->recv = m41t80_recv; 107 sc->event = m41t80_event; 108 } 109 110 static const TypeInfo m41t80_info = { 111 .name = TYPE_M41T80, 112 .parent = TYPE_I2C_SLAVE, 113 .instance_size = sizeof(M41t80State), 114 .class_init = m41t80_class_init, 115 }; 116 117 static void m41t80_register_types(void) 118 { 119 type_register_static(&m41t80_info); 120 } 121 122 type_init(m41t80_register_types) 123