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