summaryrefslogtreecommitdiff
path: root/src/include/pc80/mc146818rtc.h
blob: f6a1c043723163af3c96210381313863e6c09f14 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
#ifndef PC80_MC146818RTC_H
#define PC80_MC146818RTC_H

#if IS_ENABLED(CONFIG_ARCH_X86)

#include <arch/io.h>
#include <types.h>

#ifndef RTC_BASE_PORT
#define RTC_BASE_PORT 0x70
#endif

#define RTC_PORT(x)	(RTC_BASE_PORT + (x))

/* control registers - Moto names
 */
#define RTC_REG_A		10
#define RTC_REG_B		11
#define RTC_REG_C		12
#define RTC_REG_D		13


/**********************************************************************
 * register details
 **********************************************************************/
#define RTC_FREQ_SELECT	RTC_REG_A

#define RTC_BOOT_NORMAL		0x1

/* update-in-progress  - set to "1" 244 microsecs before RTC goes off the bus,
 * reset after update (may take 1.984ms @ 32768Hz RefClock) is complete,
 * totaling to a max high interval of 2.228 ms.
 */
# define RTC_UIP		0x80
# define RTC_DIV_CTL		0x70
   /* divider control: refclock values 4.194 / 1.049 MHz / 32.768 kHz */
#  define RTC_REF_CLCK_4MHZ	0x00
#  define RTC_REF_CLCK_1MHZ	0x10
#  define RTC_REF_CLCK_32KHZ	0x20
   /* 2 values for divider stage reset, others for "testing purposes only" */
#  define RTC_DIV_RESET1	0x60
#  define RTC_DIV_RESET2	0x70
  /* Periodic intr. / Square wave rate select. 0 = none,
   * 1 = 32.8kHz,... 15 = 2Hz
   */
# define RTC_RATE_SELECT	0x0F
#  define RTC_RATE_NONE		0x00
#  define RTC_RATE_32786HZ	0x01
#  define RTC_RATE_16384HZ	0x02
#  define RTC_RATE_8192HZ	0x03
#  define RTC_RATE_4096HZ	0x04
#  define RTC_RATE_2048HZ	0x05
#  define RTC_RATE_1024HZ	0x06
#  define RTC_RATE_512HZ	0x07
#  define RTC_RATE_256HZ	0x08
#  define RTC_RATE_128HZ	0x09
#  define RTC_RATE_64HZ		0x0a
#  define RTC_RATE_32HZ		0x0b
#  define RTC_RATE_16HZ		0x0c
#  define RTC_RATE_8HZ		0x0d
#  define RTC_RATE_4HZ		0x0e
#  define RTC_RATE_2HZ		0x0f

/**********************************************************************/
#define RTC_CONTROL	RTC_REG_B
# define RTC_SET 0x80		/* disable updates for clock setting */
# define RTC_PIE 0x40		/* periodic interrupt enable */
# define RTC_AIE 0x20		/* alarm interrupt enable */
# define RTC_UIE 0x10		/* update-finished interrupt enable */
# define RTC_SQWE 0x08		/* enable square-wave output */
# define RTC_DM_BINARY 0x04	/* all time/date values are BCD if clear */
# define RTC_24H 0x02		/* 24 hour mode - else hours bit 7 means pm */
# define RTC_DST_EN 0x01	/* auto switch DST - works f. USA only */

/**********************************************************************/
#define RTC_INTR_FLAGS	RTC_REG_C
/* caution - cleared by read */
# define RTC_IRQF 0x80		/* any of the following 3 is active */
# define RTC_PF 0x40
# define RTC_AF 0x20
# define RTC_UF 0x10

/**********************************************************************/
#define RTC_VALID	RTC_REG_D
# define RTC_VRT 0x80		/* valid RAM and time */
/**********************************************************************/

/* Date and Time in RTC CMOS */
#define RTC_CLK_SECOND		0
#define RTC_CLK_SECOND_ALARM	1
#define RTC_CLK_MINUTE		2
#define RTC_CLK_MINUTE_ALARM	3
#define RTC_CLK_HOUR		4
#define RTC_CLK_HOUR_ALARM	5
#define RTC_CLK_DAYOFWEEK	6
#define RTC_CLK_DAYOFMONTH	7
#define RTC_CLK_MONTH		8
#define RTC_CLK_YEAR		9
#define RTC_CLK_ALTCENTURY	0x32

/* On PCs, the checksum is built only over bytes 16..45 */
#define PC_CKS_RANGE_START	16
#define PC_CKS_RANGE_END	45
#define PC_CKS_LOC		46

static inline unsigned char cmos_read(unsigned char addr)
{
	int offs = 0;
	if (addr >= 128) {
		offs = 2;
		addr -= 128;
	}
	outb(addr, RTC_BASE_PORT + offs + 0);
	return inb(RTC_BASE_PORT + offs + 1);
}

/* Upon return the caller is guaranteed 244 microseconds to complete any
 * RTC operations.  wait_uip may be called a single time prior to multiple
 * accesses, but sequences requiring more time should call wait_uip again.
 */
static inline void wait_uip(void)
{
	while (cmos_read(RTC_REG_A) & RTC_UIP)
		;
}

static inline void cmos_write_inner(unsigned char val, unsigned char addr)
{
	int offs = 0;
	if (addr >= 128) {
		offs = 2;
		addr -= 128;
	}
	outb(addr, RTC_BASE_PORT + offs + 0);
	outb(val, RTC_BASE_PORT + offs + 1);
}

static inline void cmos_write(unsigned char val, unsigned char addr)
{
	u8 control_state = cmos_read(RTC_CONTROL);
	/* There are various places where RTC bits might be hiding,
	 * eg. the Century / AltCentury byte. So to be safe, disable
	 * RTC before changing any value.
	 */
	if ((addr != RTC_CONTROL) && !(control_state & RTC_SET))
		cmos_write_inner(control_state | RTC_SET, RTC_CONTROL);
	cmos_write_inner(val, addr);
	/* reset to prior configuration */
	if ((addr != RTC_CONTROL) && !(control_state & RTC_SET))
		cmos_write_inner(control_state, RTC_CONTROL);
}

static inline void cmos_disable_rtc(void)
{
	u8 control_state = cmos_read(RTC_CONTROL);
	cmos_write(control_state | RTC_SET, RTC_CONTROL);
}

static inline void cmos_enable_rtc(void)
{
	u8 control_state = cmos_read(RTC_CONTROL);
	cmos_write(control_state & ~RTC_SET, RTC_CONTROL);
}

static inline u32 cmos_read32(u8 offset)
{
	u32 value = 0;
	u8 i;
	for (i = 0; i < sizeof(value); ++i)
		value |= cmos_read(offset + i) << (i << 3);
	return value;
}

static inline void cmos_write32(u8 offset, u32 value)
{
	u8 i;
	for (i = 0; i < sizeof(value); ++i)
		cmos_write((value >> (i << 3)) & 0xff, offset + i);
}

#if !defined(__ROMCC__)
void cmos_init(bool invalid);
void cmos_check_update_date(void);

enum cb_err set_option(const char *name, void *val);
enum cb_err get_option(void *dest, const char *name);
unsigned int read_option_lowlevel(unsigned int start, unsigned int size,
	unsigned int def);

#else /* defined(__ROMCC__) */
#include <drivers/pc80/rtc/mc146818rtc_romcc.c>
#endif /* !defined(__ROMCC__) */
#define read_option(name, default) read_option_lowlevel(CMOS_VSTART_ ##name, \
	CMOS_VLEN_ ##name, (default))

#if IS_ENABLED(CONFIG_CMOS_POST)
#if IS_ENABLED(CONFIG_USE_OPTION_TABLE)
# include "option_table.h"
# define CMOS_POST_OFFSET (CMOS_VSTART_cmos_post_offset >> 3)
#else
# if defined(CONFIG_CMOS_POST_OFFSET) && CONFIG_CMOS_POST_OFFSET
#  define CMOS_POST_OFFSET CONFIG_CMOS_POST_OFFSET
# else
#  error "Must configure CONFIG_CMOS_POST_OFFSET"
# endif
#endif

/*
 *    0 = Bank Select Magic
 *    1 = Bank 0 POST
 *    2 = Bank 1 POST
 *  3-6 = BANK 0 Extra log
 * 7-10 = BANK 1 Extra log
 */
#define CMOS_POST_BANK_OFFSET     (CMOS_POST_OFFSET)
#define CMOS_POST_BANK_0_MAGIC    0x80
#define CMOS_POST_BANK_0_OFFSET   (CMOS_POST_OFFSET + 1)
#define CMOS_POST_BANK_0_EXTRA    (CMOS_POST_OFFSET + 3)
#define CMOS_POST_BANK_1_MAGIC    0x81
#define CMOS_POST_BANK_1_OFFSET   (CMOS_POST_OFFSET + 2)
#define CMOS_POST_BANK_1_EXTRA    (CMOS_POST_OFFSET + 7)

#define CMOS_POST_EXTRA_DEV_PATH  0x01

void cmos_post_log(void);

/* cmos_post_init() is exposed in this manner because it also needs to be called
 * by bootblock code compiled by romcc. */
static inline void cmos_post_init(void)
{
	u8 magic = CMOS_POST_BANK_0_MAGIC;

	/* Switch to the other bank */
	switch (cmos_read(CMOS_POST_BANK_OFFSET)) {
	case CMOS_POST_BANK_1_MAGIC:
		break;
	case CMOS_POST_BANK_0_MAGIC:
		magic = CMOS_POST_BANK_1_MAGIC;
		break;
	default:
		/* Initialize to zero */
		cmos_write(0, CMOS_POST_BANK_0_OFFSET);
		cmos_write(0, CMOS_POST_BANK_1_OFFSET);
#if IS_ENABLED(CONFIG_CMOS_POST_EXTRA)
		cmos_write32(CMOS_POST_BANK_0_EXTRA, 0);
		cmos_write32(CMOS_POST_BANK_1_EXTRA, 0);
#endif
	}

	cmos_write(magic, CMOS_POST_BANK_OFFSET);
}
#else
static inline void cmos_post_log(void) {}
static inline void cmos_post_init(void) {}
#endif /* CONFIG_CMOS_POST */

#else /* !CONFIG_ARCH_X86 */
static inline void cmos_post_init(void) {}
#endif /* CONFIG_ARCH_X86 */

#endif /*  PC80_MC146818RTC_H */