diff options
Diffstat (limited to 'hw/mc146818rtc.c')
| -rw-r--r-- | hw/mc146818rtc.c | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/hw/mc146818rtc.c b/hw/mc146818rtc.c new file mode 100644 index 0000000000..cab76cfab2 --- /dev/null +++ b/hw/mc146818rtc.c @@ -0,0 +1,203 @@ +/* + * QEMU MC146818 RTC emulation + * + * Copyright (c) 2003-2004 Fabrice Bellard + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ +#include <stdlib.h> +#include <stdio.h> +#include <stdarg.h> +#include <string.h> +#include <getopt.h> +#include <inttypes.h> +#include <unistd.h> +#include <sys/mman.h> +#include <fcntl.h> +#include <signal.h> +#include <time.h> +#include <sys/time.h> +#include <malloc.h> +#include <termios.h> +#include <sys/poll.h> +#include <errno.h> +#include <sys/wait.h> +#include <netinet/in.h> + +#include "cpu.h" +#include "vl.h" + +//#define DEBUG_CMOS + +#define RTC_SECONDS 0 +#define RTC_SECONDS_ALARM 1 +#define RTC_MINUTES 2 +#define RTC_MINUTES_ALARM 3 +#define RTC_HOURS 4 +#define RTC_HOURS_ALARM 5 +#define RTC_ALARM_DONT_CARE 0xC0 + +#define RTC_DAY_OF_WEEK 6 +#define RTC_DAY_OF_MONTH 7 +#define RTC_MONTH 8 +#define RTC_YEAR 9 + +#define RTC_REG_A 10 +#define RTC_REG_B 11 +#define RTC_REG_C 12 +#define RTC_REG_D 13 + +/* PC cmos mappings */ +#define REG_IBM_CENTURY_BYTE 0x32 +#define REG_IBM_PS2_CENTURY_BYTE 0x37 + +RTCState rtc_state; + +static void cmos_ioport_write(CPUState *env, uint32_t addr, uint32_t data) +{ + RTCState *s = &rtc_state; + + if ((addr & 1) == 0) { + s->cmos_index = data & 0x7f; + } else { +#ifdef DEBUG_CMOS + printf("cmos: write index=0x%02x val=0x%02x\n", + s->cmos_index, data); +#endif + switch(addr) { + case RTC_SECONDS_ALARM: + case RTC_MINUTES_ALARM: + case RTC_HOURS_ALARM: + /* XXX: not supported */ + s->cmos_data[s->cmos_index] = data; + break; + case RTC_SECONDS: + case RTC_MINUTES: + case RTC_HOURS: + case RTC_DAY_OF_WEEK: + case RTC_DAY_OF_MONTH: + case RTC_MONTH: + case RTC_YEAR: + s->cmos_data[s->cmos_index] = data; + break; + case RTC_REG_A: + case RTC_REG_B: + s->cmos_data[s->cmos_index] = data; + break; + case RTC_REG_C: + case RTC_REG_D: + /* cannot write to them */ + break; + default: + s->cmos_data[s->cmos_index] = data; + break; + } + } +} + +static inline int to_bcd(int a) +{ + return ((a / 10) << 4) | (a % 10); +} + +static void cmos_update_time(RTCState *s) +{ + struct tm *tm; + time_t ti; + + ti = time(NULL); + tm = gmtime(&ti); + s->cmos_data[RTC_SECONDS] = to_bcd(tm->tm_sec); + s->cmos_data[RTC_MINUTES] = to_bcd(tm->tm_min); + s->cmos_data[RTC_HOURS] = to_bcd(tm->tm_hour); + s->cmos_data[RTC_DAY_OF_WEEK] = to_bcd(tm->tm_wday); + s->cmos_data[RTC_DAY_OF_MONTH] = to_bcd(tm->tm_mday); + s->cmos_data[RTC_MONTH] = to_bcd(tm->tm_mon + 1); + s->cmos_data[RTC_YEAR] = to_bcd(tm->tm_year % 100); + s->cmos_data[REG_IBM_CENTURY_BYTE] = to_bcd((tm->tm_year / 100) + 19); + s->cmos_data[REG_IBM_PS2_CENTURY_BYTE] = s->cmos_data[REG_IBM_CENTURY_BYTE]; +} + +static uint32_t cmos_ioport_read(CPUState *env, uint32_t addr) +{ + RTCState *s = &rtc_state; + int ret; + if ((addr & 1) == 0) { + return 0xff; + } else { + switch(s->cmos_index) { + case RTC_SECONDS: + case RTC_MINUTES: + case RTC_HOURS: + case RTC_DAY_OF_WEEK: + case RTC_DAY_OF_MONTH: + case RTC_MONTH: + case RTC_YEAR: + case REG_IBM_CENTURY_BYTE: + case REG_IBM_PS2_CENTURY_BYTE: + cmos_update_time(s); + ret = s->cmos_data[s->cmos_index]; + break; + case RTC_REG_A: + ret = s->cmos_data[s->cmos_index]; + /* toggle update-in-progress bit for Linux (same hack as + plex86) */ + s->cmos_data[RTC_REG_A] ^= 0x80; + break; + case RTC_REG_C: + ret = s->cmos_data[s->cmos_index]; + pic_set_irq(s->irq, 0); + s->cmos_data[RTC_REG_C] = 0x00; + break; + default: + ret = s->cmos_data[s->cmos_index]; + break; + } +#ifdef DEBUG_CMOS + printf("cmos: read index=0x%02x val=0x%02x\n", + s->cmos_index, ret); +#endif + return ret; + } +} + +void rtc_timer(void) +{ + RTCState *s = &rtc_state; + if (s->cmos_data[RTC_REG_B] & 0x50) { + pic_set_irq(s->irq, 1); + } +} + +void rtc_init(int base, int irq) +{ + RTCState *s = &rtc_state; + + cmos_update_time(s); + + s->irq = irq; + s->cmos_data[RTC_REG_A] = 0x26; + s->cmos_data[RTC_REG_B] = 0x02; + s->cmos_data[RTC_REG_C] = 0x00; + s->cmos_data[RTC_REG_D] = 0x80; + + register_ioport_write(base, 2, cmos_ioport_write, 1); + register_ioport_read(base, 2, cmos_ioport_read, 1); +} + |