xref: /kvmtool/hw/rtc.c (revision 4346fd8f1ef04040775965c8476be61ad8e15643)
164136c1cSPekka Enberg #include "kvm/rtc.h"
264136c1cSPekka Enberg 
364136c1cSPekka Enberg #include "kvm/ioport.h"
464136c1cSPekka Enberg #include "kvm/kvm.h"
564136c1cSPekka Enberg 
664136c1cSPekka Enberg #include <time.h>
764136c1cSPekka Enberg 
8c8f6893bSPekka Enberg /*
9c8f6893bSPekka Enberg  * MC146818 RTC registers
10c8f6893bSPekka Enberg  */
11c8f6893bSPekka Enberg #define RTC_SECONDS			0x00
12c8f6893bSPekka Enberg #define RTC_SECONDS_ALARM		0x01
13c8f6893bSPekka Enberg #define RTC_MINUTES			0x02
14c8f6893bSPekka Enberg #define RTC_MINUTES_ALARM		0x03
15c8f6893bSPekka Enberg #define RTC_HOURS			0x04
16c8f6893bSPekka Enberg #define RTC_HOURS_ALARM			0x05
17c8f6893bSPekka Enberg #define RTC_DAY_OF_WEEK			0x06
18c8f6893bSPekka Enberg #define RTC_DAY_OF_MONTH		0x07
19c8f6893bSPekka Enberg #define RTC_MONTH			0x08
20c8f6893bSPekka Enberg #define RTC_YEAR			0x09
21c8f6893bSPekka Enberg 
22c8f6893bSPekka Enberg #define RTC_REG_A			0x0A
23c8f6893bSPekka Enberg #define RTC_REG_B			0x0B
24c8f6893bSPekka Enberg #define RTC_REG_C			0x0C
25c8f6893bSPekka Enberg #define RTC_REG_D			0x0D
2664136c1cSPekka Enberg 
272f062989SPekka Enberg struct rtc_device {
282f062989SPekka Enberg 	u8			cmos_idx;
29d951bae0SPekka Enberg 	u8			cmos_data[128];
302f062989SPekka Enberg };
312f062989SPekka Enberg 
322f062989SPekka Enberg static struct rtc_device	rtc;
332f062989SPekka Enberg 
3464136c1cSPekka Enberg static inline unsigned char bin2bcd(unsigned val)
3564136c1cSPekka Enberg {
3664136c1cSPekka Enberg 	return ((val / 10) << 4) + val % 10;
3764136c1cSPekka Enberg }
3864136c1cSPekka Enberg 
39c9f6a037SXiao Guangrong static bool cmos_ram_data_in(struct ioport *ioport, struct kvm *kvm, u16 port, void *data, int size)
4064136c1cSPekka Enberg {
4164136c1cSPekka Enberg 	struct tm *tm;
4264136c1cSPekka Enberg 	time_t ti;
4364136c1cSPekka Enberg 
4464136c1cSPekka Enberg 	time(&ti);
4564136c1cSPekka Enberg 
4664136c1cSPekka Enberg 	tm = gmtime(&ti);
4764136c1cSPekka Enberg 
482f062989SPekka Enberg 	switch (rtc.cmos_idx) {
49c8f6893bSPekka Enberg 	case RTC_SECONDS:
5064136c1cSPekka Enberg 		ioport__write8(data, bin2bcd(tm->tm_sec));
5164136c1cSPekka Enberg 		break;
52c8f6893bSPekka Enberg 	case RTC_MINUTES:
5364136c1cSPekka Enberg 		ioport__write8(data, bin2bcd(tm->tm_min));
5464136c1cSPekka Enberg 		break;
55c8f6893bSPekka Enberg 	case RTC_HOURS:
5664136c1cSPekka Enberg 		ioport__write8(data, bin2bcd(tm->tm_hour));
5764136c1cSPekka Enberg 		break;
58c717392fSPekka Enberg 	case RTC_DAY_OF_WEEK:
59c717392fSPekka Enberg 		ioport__write8(data, bin2bcd(tm->tm_wday + 1));
60c717392fSPekka Enberg 		break;
61c8f6893bSPekka Enberg 	case RTC_DAY_OF_MONTH:
6264136c1cSPekka Enberg 		ioport__write8(data, bin2bcd(tm->tm_mday));
6364136c1cSPekka Enberg 		break;
64c8f6893bSPekka Enberg 	case RTC_MONTH:
6564136c1cSPekka Enberg 		ioport__write8(data, bin2bcd(tm->tm_mon + 1));
6664136c1cSPekka Enberg 		break;
67c8f6893bSPekka Enberg 	case RTC_YEAR:
6864136c1cSPekka Enberg 		ioport__write8(data, bin2bcd(tm->tm_year));
6964136c1cSPekka Enberg 		break;
70d951bae0SPekka Enberg 	default:
71d951bae0SPekka Enberg 		ioport__write8(data, rtc.cmos_data[rtc.cmos_idx]);
72d951bae0SPekka Enberg 		break;
7364136c1cSPekka Enberg 	}
7464136c1cSPekka Enberg 
7564136c1cSPekka Enberg 	return true;
7664136c1cSPekka Enberg }
7764136c1cSPekka Enberg 
78c9f6a037SXiao Guangrong static bool cmos_ram_data_out(struct ioport *ioport, struct kvm *kvm, u16 port, void *data, int size)
7964136c1cSPekka Enberg {
80d951bae0SPekka Enberg 	switch (rtc.cmos_idx) {
81d951bae0SPekka Enberg 	case RTC_REG_C:
82d951bae0SPekka Enberg 	case RTC_REG_D:
83d951bae0SPekka Enberg 		/* Read-only */
84d951bae0SPekka Enberg 		break;
85d951bae0SPekka Enberg 	default:
86d951bae0SPekka Enberg 		rtc.cmos_data[rtc.cmos_idx] = ioport__read8(data);
87d951bae0SPekka Enberg 		break;
88d951bae0SPekka Enberg 	}
89d951bae0SPekka Enberg 
9064136c1cSPekka Enberg 	return true;
9164136c1cSPekka Enberg }
9264136c1cSPekka Enberg 
9364136c1cSPekka Enberg static struct ioport_operations cmos_ram_data_ioport_ops = {
9464136c1cSPekka Enberg 	.io_out		= cmos_ram_data_out,
9564136c1cSPekka Enberg 	.io_in		= cmos_ram_data_in,
9664136c1cSPekka Enberg };
9764136c1cSPekka Enberg 
98c9f6a037SXiao Guangrong static bool cmos_ram_index_out(struct ioport *ioport, struct kvm *kvm, u16 port, void *data, int size)
9964136c1cSPekka Enberg {
1002f062989SPekka Enberg 	u8 value = ioport__read8(data);
10164136c1cSPekka Enberg 
10243835ac9SSasha Levin 	kvm->nmi_disabled	= value & (1UL << 7);
1032f062989SPekka Enberg 	rtc.cmos_idx		= value & ~(1UL << 7);
10464136c1cSPekka Enberg 
10564136c1cSPekka Enberg 	return true;
10664136c1cSPekka Enberg }
10764136c1cSPekka Enberg 
10864136c1cSPekka Enberg static struct ioport_operations cmos_ram_index_ioport_ops = {
10964136c1cSPekka Enberg 	.io_out		= cmos_ram_index_out,
11064136c1cSPekka Enberg };
11164136c1cSPekka Enberg 
11220c39545SSasha Levin int rtc__init(struct kvm *kvm)
11320c39545SSasha Levin {
11420c39545SSasha Levin 	int r = 0;
11520c39545SSasha Levin 
11620c39545SSasha Levin 	/* PORT 0070-007F - CMOS RAM/RTC (REAL TIME CLOCK) */
117*4346fd8fSSasha Levin 	r = ioport__register(kvm, 0x0070, &cmos_ram_index_ioport_ops, 1, NULL);
11820c39545SSasha Levin 	if (r < 0)
11920c39545SSasha Levin 		return r;
12020c39545SSasha Levin 
121*4346fd8fSSasha Levin 	r = ioport__register(kvm, 0x0071, &cmos_ram_data_ioport_ops, 1, NULL);
12220c39545SSasha Levin 	if (r < 0) {
123*4346fd8fSSasha Levin 		ioport__unregister(kvm, 0x0071);
12420c39545SSasha Levin 		return r;
12520c39545SSasha Levin 	}
12620c39545SSasha Levin 
12720c39545SSasha Levin 	return r;
12820c39545SSasha Levin }
12949a8afd1SSasha Levin dev_init(rtc__init);
13020c39545SSasha Levin 
13120c39545SSasha Levin int rtc__exit(struct kvm *kvm)
13264136c1cSPekka Enberg {
13364136c1cSPekka Enberg 	/* PORT 0070-007F - CMOS RAM/RTC (REAL TIME CLOCK) */
134*4346fd8fSSasha Levin 	ioport__unregister(kvm, 0x0070);
135*4346fd8fSSasha Levin 	ioport__unregister(kvm, 0x0071);
13620c39545SSasha Levin 
13720c39545SSasha Levin 	return 0;
13864136c1cSPekka Enberg }
13949a8afd1SSasha Levin dev_exit(rtc__exit);
140