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git.ipfire.org Git - thirdparty/u-boot.git/blob - drivers/rtc/ds1306.c
2 * (C) Copyright 2002 SIXNET, dge@sixnetio.com.
4 * (C) Copyright 2004, Li-Pro.Net <www.li-pro.net>
5 * Stephan Linz <linz@li-pro.net>
7 * SPDX-License-Identifier: GPL-2.0+
11 * Date & Time support for DS1306 RTC using SPI:
13 * - SXNI855T: it uses its own soft SPI here in this file
14 * - all other: use the external spi_xfer() function
23 #if defined(CONFIG_CMD_DATE)
25 #define RTC_SECONDS 0x00
26 #define RTC_MINUTES 0x01
27 #define RTC_HOURS 0x02
28 #define RTC_DAY_OF_WEEK 0x03
29 #define RTC_DATE_OF_MONTH 0x04
30 #define RTC_MONTH 0x05
33 #define RTC_SECONDS_ALARM0 0x07
34 #define RTC_MINUTES_ALARM0 0x08
35 #define RTC_HOURS_ALARM0 0x09
36 #define RTC_DAY_OF_WEEK_ALARM0 0x0a
38 #define RTC_SECONDS_ALARM1 0x0b
39 #define RTC_MINUTES_ALARM1 0x0c
40 #define RTC_HOURS_ALARM1 0x0d
41 #define RTC_DAY_OF_WEEK_ALARM1 0x0e
43 #define RTC_CONTROL 0x0f
44 #define RTC_STATUS 0x10
45 #define RTC_TRICKLE_CHARGER 0x11
47 #define RTC_USER_RAM_BASE 0x20
49 /* ************************************************************************* */
50 #ifdef CONFIG_SXNI855T /* !!! SHOULD BE CHANGED TO NEW CODE !!! */
52 static void soft_spi_send (unsigned char n
);
53 static unsigned char soft_spi_read (void);
54 static void init_spi (void);
56 /*-----------------------------------------------------------------------
60 #define PB_SPISCK 0x00000002 /* PB 30 */
61 #define PB_SPIMOSI 0x00000004 /* PB 29 */
62 #define PB_SPIMISO 0x00000008 /* PB 28 */
63 #define PB_SPI_CE 0x00010000 /* PB 15 */
65 /* ------------------------------------------------------------------------- */
67 /* read clock time from DS1306 and return it in *tmp */
68 int rtc_get (struct rtc_time
*tmp
)
70 volatile immap_t
*immap
= (immap_t
*) CONFIG_SYS_IMMR
;
71 unsigned char spi_byte
; /* Data Byte */
73 init_spi (); /* set port B for software SPI */
75 /* Now we can enable the DS1306 RTC */
76 immap
->im_cpm
.cp_pbdat
|= PB_SPI_CE
;
79 /* Shift out the address (0) of the time in the Clock Chip */
82 /* Put the clock readings into the rtc_time structure */
83 tmp
->tm_sec
= bcd2bin (soft_spi_read ()); /* Read seconds */
84 tmp
->tm_min
= bcd2bin (soft_spi_read ()); /* Read minutes */
86 /* Hours are trickier */
87 spi_byte
= soft_spi_read (); /* Read Hours into temporary value */
88 if (spi_byte
& 0x40) {
89 /* 12 hour mode bit is set (time is in 1-12 format) */
90 if (spi_byte
& 0x20) {
91 /* since PM we add 11 to get 0-23 for hours */
92 tmp
->tm_hour
= (bcd2bin (spi_byte
& 0x1F)) + 11;
94 /* since AM we subtract 1 to get 0-23 for hours */
95 tmp
->tm_hour
= (bcd2bin (spi_byte
& 0x1F)) - 1;
98 /* Otherwise, 0-23 hour format */
99 tmp
->tm_hour
= (bcd2bin (spi_byte
& 0x3F));
102 soft_spi_read (); /* Read and discard Day of week */
103 tmp
->tm_mday
= bcd2bin (soft_spi_read ()); /* Read Day of the Month */
104 tmp
->tm_mon
= bcd2bin (soft_spi_read ()); /* Read Month */
106 /* Read Year and convert to this century */
107 tmp
->tm_year
= bcd2bin (soft_spi_read ()) + 2000;
109 /* Now we can disable the DS1306 RTC */
110 immap
->im_cpm
.cp_pbdat
&= ~PB_SPI_CE
; /* Disable DS1306 Chip */
113 GregorianDay (tmp
); /* Determine the day of week */
115 debug ("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
116 tmp
->tm_year
, tmp
->tm_mon
, tmp
->tm_mday
, tmp
->tm_wday
,
117 tmp
->tm_hour
, tmp
->tm_min
, tmp
->tm_sec
);
122 /* ------------------------------------------------------------------------- */
124 /* set clock time in DS1306 RTC and in MPC8xx RTC */
125 int rtc_set (struct rtc_time
*tmp
)
127 volatile immap_t
*immap
= (immap_t
*) CONFIG_SYS_IMMR
;
129 init_spi (); /* set port B for software SPI */
131 /* Now we can enable the DS1306 RTC */
132 immap
->im_cpm
.cp_pbdat
|= PB_SPI_CE
; /* Enable DS1306 Chip */
135 /* First disable write protect in the clock chip control register */
136 soft_spi_send (0x8F); /* send address of the control register */
137 soft_spi_send (0x00); /* send control register contents */
139 /* Now disable the DS1306 to terminate the write */
140 immap
->im_cpm
.cp_pbdat
&= ~PB_SPI_CE
;
143 /* Now enable the DS1306 to initiate a new write */
144 immap
->im_cpm
.cp_pbdat
|= PB_SPI_CE
;
147 /* Next, send the address of the clock time write registers */
148 soft_spi_send (0x80); /* send address of the first time register */
150 /* Use Burst Mode to send all of the time data to the clock */
151 bin2bcd (tmp
->tm_sec
);
152 soft_spi_send (bin2bcd (tmp
->tm_sec
)); /* Send Seconds */
153 soft_spi_send (bin2bcd (tmp
->tm_min
)); /* Send Minutes */
154 soft_spi_send (bin2bcd (tmp
->tm_hour
)); /* Send Hour */
155 soft_spi_send (bin2bcd (tmp
->tm_wday
)); /* Send Day of the Week */
156 soft_spi_send (bin2bcd (tmp
->tm_mday
)); /* Send Day of Month */
157 soft_spi_send (bin2bcd (tmp
->tm_mon
)); /* Send Month */
158 soft_spi_send (bin2bcd (tmp
->tm_year
- 2000)); /* Send Year */
160 /* Now we can disable the Clock chip to terminate the burst write */
161 immap
->im_cpm
.cp_pbdat
&= ~PB_SPI_CE
; /* Disable DS1306 Chip */
164 /* Now we can enable the Clock chip to initiate a new write */
165 immap
->im_cpm
.cp_pbdat
|= PB_SPI_CE
; /* Enable DS1306 Chip */
168 /* First we Enable write protect in the clock chip control register */
169 soft_spi_send (0x8F); /* send address of the control register */
170 soft_spi_send (0x40); /* send out Control Register contents */
172 /* Now disable the DS1306 */
173 immap
->im_cpm
.cp_pbdat
&= ~PB_SPI_CE
; /* Disable DS1306 Chip */
176 /* Set standard MPC8xx clock to the same time so Linux will
177 * see the time even if it doesn't have a DS1306 clock driver.
178 * This helps with experimenting with standard kernels.
183 tim
= mktime (tmp
->tm_year
, tmp
->tm_mon
, tmp
->tm_mday
,
184 tmp
->tm_hour
, tmp
->tm_min
, tmp
->tm_sec
);
186 immap
->im_sitk
.sitk_rtck
= KAPWR_KEY
;
187 immap
->im_sit
.sit_rtc
= tim
;
190 debug ("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
191 tmp
->tm_year
, tmp
->tm_mon
, tmp
->tm_mday
, tmp
->tm_wday
,
192 tmp
->tm_hour
, tmp
->tm_min
, tmp
->tm_sec
);
197 /* ------------------------------------------------------------------------- */
199 /* Initialize Port B for software SPI */
200 static void init_spi (void)
202 volatile immap_t
*immap
= (immap_t
*) CONFIG_SYS_IMMR
;
204 /* Force output pins to begin at logic 0 */
205 immap
->im_cpm
.cp_pbdat
&= ~(PB_SPI_CE
| PB_SPIMOSI
| PB_SPISCK
);
207 /* Set these 3 signals as outputs */
208 immap
->im_cpm
.cp_pbdir
|= (PB_SPIMOSI
| PB_SPI_CE
| PB_SPISCK
);
210 immap
->im_cpm
.cp_pbdir
&= ~PB_SPIMISO
; /* Make MISO pin an input */
214 /* ------------------------------------------------------------------------- */
216 /* NOTE: soft_spi_send() assumes that the I/O lines are configured already */
217 static void soft_spi_send (unsigned char n
)
219 volatile immap_t
*immap
= (immap_t
*) CONFIG_SYS_IMMR
;
220 unsigned char bitpos
; /* bit position to receive */
221 unsigned char i
; /* Loop Control */
223 /* bit position to send, start with most significant bit */
226 /* Send 8 bits to software SPI */
227 for (i
= 0; i
< 8; i
++) { /* Loop for 8 bits */
228 immap
->im_cpm
.cp_pbdat
|= PB_SPISCK
; /* Raise SCK */
231 immap
->im_cpm
.cp_pbdat
|= PB_SPIMOSI
; /* Set MOSI to 1 */
233 immap
->im_cpm
.cp_pbdat
&= ~PB_SPIMOSI
; /* Set MOSI to 0 */
236 immap
->im_cpm
.cp_pbdat
&= ~PB_SPISCK
; /* Lower SCK */
239 bitpos
>>= 1; /* Shift for next bit position */
243 /* ------------------------------------------------------------------------- */
245 /* NOTE: soft_spi_read() assumes that the I/O lines are configured already */
246 static unsigned char soft_spi_read (void)
248 volatile immap_t
*immap
= (immap_t
*) CONFIG_SYS_IMMR
;
250 unsigned char spi_byte
= 0; /* Return value, assume success */
251 unsigned char bitpos
; /* bit position to receive */
252 unsigned char i
; /* Loop Control */
254 /* bit position to receive, start with most significant bit */
257 /* Read 8 bits here */
258 for (i
= 0; i
< 8; i
++) { /* Do 8 bits in loop */
259 immap
->im_cpm
.cp_pbdat
|= PB_SPISCK
; /* Raise SCK */
261 if (immap
->im_cpm
.cp_pbdat
& PB_SPIMISO
) /* Get a bit of data */
262 spi_byte
|= bitpos
; /* Set data accordingly */
263 immap
->im_cpm
.cp_pbdat
&= ~PB_SPISCK
; /* Lower SCK */
265 bitpos
>>= 1; /* Shift for next bit position */
268 return spi_byte
; /* Return the byte read */
271 /* ------------------------------------------------------------------------- */
273 void rtc_reset (void)
275 return; /* nothing to do */
278 #else /* not CONFIG_SXNI855T */
279 /* ************************************************************************* */
281 static unsigned char rtc_read (unsigned char reg
);
282 static void rtc_write (unsigned char reg
, unsigned char val
);
284 static struct spi_slave
*slave
;
286 /* read clock time from DS1306 and return it in *tmp */
287 int rtc_get (struct rtc_time
*tmp
)
289 unsigned char sec
, min
, hour
, mday
, wday
, mon
, year
;
292 * Assuming Vcc = 2.0V (lowest speed)
294 * REVISIT: If we add an rtc_init() function we can do this
298 slave
= spi_setup_slave(0, CONFIG_SYS_SPI_RTC_DEVID
, 600000,
299 SPI_MODE_3
| SPI_CS_HIGH
);
304 if (spi_claim_bus(slave
))
307 sec
= rtc_read (RTC_SECONDS
);
308 min
= rtc_read (RTC_MINUTES
);
309 hour
= rtc_read (RTC_HOURS
);
310 mday
= rtc_read (RTC_DATE_OF_MONTH
);
311 wday
= rtc_read (RTC_DAY_OF_WEEK
);
312 mon
= rtc_read (RTC_MONTH
);
313 year
= rtc_read (RTC_YEAR
);
315 spi_release_bus(slave
);
317 debug ("Get RTC year: %02x mon: %02x mday: %02x wday: %02x "
318 "hr: %02x min: %02x sec: %02x\n",
319 year
, mon
, mday
, wday
, hour
, min
, sec
);
320 debug ("Alarms[0]: wday: %02x hour: %02x min: %02x sec: %02x\n",
321 rtc_read (RTC_DAY_OF_WEEK_ALARM0
),
322 rtc_read (RTC_HOURS_ALARM0
),
323 rtc_read (RTC_MINUTES_ALARM0
), rtc_read (RTC_SECONDS_ALARM0
));
324 debug ("Alarms[1]: wday: %02x hour: %02x min: %02x sec: %02x\n",
325 rtc_read (RTC_DAY_OF_WEEK_ALARM1
),
326 rtc_read (RTC_HOURS_ALARM1
),
327 rtc_read (RTC_MINUTES_ALARM1
), rtc_read (RTC_SECONDS_ALARM1
));
329 tmp
->tm_sec
= bcd2bin (sec
& 0x7F); /* convert Seconds */
330 tmp
->tm_min
= bcd2bin (min
& 0x7F); /* convert Minutes */
333 tmp
->tm_hour
= (hour
& 0x40)
334 ? ((hour
& 0x20) /* 12 hour mode */
335 ? bcd2bin (hour
& 0x1F) + 11 /* PM */
336 : bcd2bin (hour
& 0x1F) - 1 /* AM */
338 : bcd2bin (hour
& 0x3F); /* 24 hour mode */
340 tmp
->tm_mday
= bcd2bin (mday
& 0x3F); /* convert Day of the Month */
341 tmp
->tm_mon
= bcd2bin (mon
& 0x1F); /* convert Month */
342 tmp
->tm_year
= bcd2bin (year
) + 2000; /* convert Year */
343 tmp
->tm_wday
= bcd2bin (wday
& 0x07) - 1; /* convert Day of the Week */
347 debug ("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
348 tmp
->tm_year
, tmp
->tm_mon
, tmp
->tm_mday
, tmp
->tm_wday
,
349 tmp
->tm_hour
, tmp
->tm_min
, tmp
->tm_sec
);
354 /* ------------------------------------------------------------------------- */
356 /* set clock time from *tmp in DS1306 RTC */
357 int rtc_set (struct rtc_time
*tmp
)
359 /* Assuming Vcc = 2.0V (lowest speed) */
361 slave
= spi_setup_slave(0, CONFIG_SYS_SPI_RTC_DEVID
, 600000,
362 SPI_MODE_3
| SPI_CS_HIGH
);
367 if (spi_claim_bus(slave
))
370 debug ("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
371 tmp
->tm_year
, tmp
->tm_mon
, tmp
->tm_mday
, tmp
->tm_wday
,
372 tmp
->tm_hour
, tmp
->tm_min
, tmp
->tm_sec
);
374 rtc_write (RTC_SECONDS
, bin2bcd (tmp
->tm_sec
));
375 rtc_write (RTC_MINUTES
, bin2bcd (tmp
->tm_min
));
376 rtc_write (RTC_HOURS
, bin2bcd (tmp
->tm_hour
));
377 rtc_write (RTC_DAY_OF_WEEK
, bin2bcd (tmp
->tm_wday
+ 1));
378 rtc_write (RTC_DATE_OF_MONTH
, bin2bcd (tmp
->tm_mday
));
379 rtc_write (RTC_MONTH
, bin2bcd (tmp
->tm_mon
));
380 rtc_write (RTC_YEAR
, bin2bcd (tmp
->tm_year
- 2000));
382 spi_release_bus(slave
);
385 /* ------------------------------------------------------------------------- */
387 /* reset the DS1306 */
388 void rtc_reset (void)
390 /* Assuming Vcc = 2.0V (lowest speed) */
392 slave
= spi_setup_slave(0, CONFIG_SYS_SPI_RTC_DEVID
, 600000,
393 SPI_MODE_3
| SPI_CS_HIGH
);
398 if (spi_claim_bus(slave
))
401 /* clear the control register */
402 rtc_write (RTC_CONTROL
, 0x00); /* 1st step: reset WP */
403 rtc_write (RTC_CONTROL
, 0x00); /* 2nd step: reset 1Hz, AIE1, AIE0 */
405 /* reset all alarms */
406 rtc_write (RTC_SECONDS_ALARM0
, 0x00);
407 rtc_write (RTC_SECONDS_ALARM1
, 0x00);
408 rtc_write (RTC_MINUTES_ALARM0
, 0x00);
409 rtc_write (RTC_MINUTES_ALARM1
, 0x00);
410 rtc_write (RTC_HOURS_ALARM0
, 0x00);
411 rtc_write (RTC_HOURS_ALARM1
, 0x00);
412 rtc_write (RTC_DAY_OF_WEEK_ALARM0
, 0x00);
413 rtc_write (RTC_DAY_OF_WEEK_ALARM1
, 0x00);
415 spi_release_bus(slave
);
418 /* ------------------------------------------------------------------------- */
420 static unsigned char rtc_read (unsigned char reg
)
424 ret
= spi_w8r8(slave
, reg
);
425 return ret
< 0 ? 0 : ret
;
428 /* ------------------------------------------------------------------------- */
430 static void rtc_write (unsigned char reg
, unsigned char val
)
432 unsigned char dout
[2]; /* SPI Output Data Bytes */
433 unsigned char din
[2]; /* SPI Input Data Bytes */
435 dout
[0] = 0x80 | reg
;
438 spi_xfer (slave
, 16, dout
, din
, SPI_XFER_BEGIN
| SPI_XFER_END
);
441 #endif /* end of code exclusion (see #ifdef CONFIG_SXNI855T above) */