xref: /linux/arch/m68k/mac/misc.c (revision 621cde16e49b3ecf7d59a8106a20aaebfb4a59a9)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Miscellaneous Mac68K-specific stuff
4  */
5 
6 #include <linux/types.h>
7 #include <linux/errno.h>
8 #include <linux/kernel.h>
9 #include <linux/delay.h>
10 #include <linux/sched.h>
11 #include <linux/time.h>
12 #include <linux/rtc.h>
13 #include <linux/mm.h>
14 
15 #include <linux/adb.h>
16 #include <linux/cuda.h>
17 #include <linux/pmu.h>
18 
19 #include <linux/uaccess.h>
20 #include <asm/io.h>
21 #include <asm/setup.h>
22 #include <asm/macintosh.h>
23 #include <asm/mac_via.h>
24 #include <asm/mac_oss.h>
25 
26 #include <asm/machdep.h>
27 
28 #include "mac.h"
29 
30 /*
31  * Offset between Unix time (1970-based) and Mac time (1904-based). Cuda and PMU
32  * times wrap in 2040. If we need to handle later times, the read_time functions
33  * need to be changed to interpret wrapped times as post-2040.
34  */
35 
36 #define RTC_OFFSET 2082844800
37 
38 static void (*rom_reset)(void);
39 
40 #if IS_ENABLED(CONFIG_NVRAM)
41 #ifdef CONFIG_ADB_CUDA
cuda_pram_read_byte(int offset)42 static unsigned char cuda_pram_read_byte(int offset)
43 {
44 	struct adb_request req;
45 
46 	if (cuda_request(&req, NULL, 4, CUDA_PACKET, CUDA_GET_PRAM,
47 			 (offset >> 8) & 0xFF, offset & 0xFF) < 0)
48 		return 0;
49 	while (!req.complete)
50 		cuda_poll();
51 	return req.reply[3];
52 }
53 
cuda_pram_write_byte(unsigned char data,int offset)54 static void cuda_pram_write_byte(unsigned char data, int offset)
55 {
56 	struct adb_request req;
57 
58 	if (cuda_request(&req, NULL, 5, CUDA_PACKET, CUDA_SET_PRAM,
59 			 (offset >> 8) & 0xFF, offset & 0xFF, data) < 0)
60 		return;
61 	while (!req.complete)
62 		cuda_poll();
63 }
64 #endif /* CONFIG_ADB_CUDA */
65 
66 #ifdef CONFIG_ADB_PMU
pmu_pram_read_byte(int offset)67 static unsigned char pmu_pram_read_byte(int offset)
68 {
69 	struct adb_request req;
70 
71 	if (pmu_request(&req, NULL, 3, PMU_READ_XPRAM,
72 	                offset & 0xFF, 1) < 0)
73 		return 0;
74 	pmu_wait_complete(&req);
75 
76 	return req.reply[0];
77 }
78 
pmu_pram_write_byte(unsigned char data,int offset)79 static void pmu_pram_write_byte(unsigned char data, int offset)
80 {
81 	struct adb_request req;
82 
83 	if (pmu_request(&req, NULL, 4, PMU_WRITE_XPRAM,
84 	                offset & 0xFF, 1, data) < 0)
85 		return;
86 	pmu_wait_complete(&req);
87 }
88 #endif /* CONFIG_ADB_PMU */
89 #endif /* CONFIG_NVRAM */
90 
91 /*
92  * VIA PRAM/RTC access routines
93  *
94  * Must be called with interrupts disabled and
95  * the RTC should be enabled.
96  */
97 
via_rtc_recv(void)98 static __u8 via_rtc_recv(void)
99 {
100 	int i, reg;
101 	__u8 data;
102 
103 	reg = via1[vBufB] & ~VIA1B_vRTCClk;
104 
105 	/* Set the RTC data line to be an input. */
106 
107 	via1[vDirB] &= ~VIA1B_vRTCData;
108 
109 	/* The bits of the byte come out in MSB order */
110 
111 	data = 0;
112 	for (i = 0 ; i < 8 ; i++) {
113 		via1[vBufB] = reg;
114 		via1[vBufB] = reg | VIA1B_vRTCClk;
115 		data = (data << 1) | (via1[vBufB] & VIA1B_vRTCData);
116 	}
117 
118 	/* Return RTC data line to output state */
119 
120 	via1[vDirB] |= VIA1B_vRTCData;
121 
122 	return data;
123 }
124 
via_rtc_send(__u8 data)125 static void via_rtc_send(__u8 data)
126 {
127 	int i, reg, bit;
128 
129 	reg = via1[vBufB] & ~(VIA1B_vRTCClk | VIA1B_vRTCData);
130 
131 	/* The bits of the byte go into the RTC in MSB order */
132 
133 	for (i = 0 ; i < 8 ; i++) {
134 		bit = data & 0x80? 1 : 0;
135 		data <<= 1;
136 		via1[vBufB] = reg | bit;
137 		via1[vBufB] = reg | bit | VIA1B_vRTCClk;
138 	}
139 }
140 
141 /*
142  * These values can be found in Inside Macintosh vol. III ch. 2
143  * which has a description of the RTC chip in the original Mac.
144  */
145 
146 #define RTC_FLG_READ            BIT(7)
147 #define RTC_FLG_WRITE_PROTECT   BIT(7)
148 #define RTC_CMD_READ(r)         (RTC_FLG_READ | (r << 2))
149 #define RTC_CMD_WRITE(r)        (r << 2)
150 #define RTC_REG_SECONDS_0       0
151 #define RTC_REG_SECONDS_1       1
152 #define RTC_REG_SECONDS_2       2
153 #define RTC_REG_SECONDS_3       3
154 #define RTC_REG_WRITE_PROTECT   13
155 
156 /*
157  * Inside Mac has no information about two-byte RTC commands but
158  * the MAME/MESS source code has the essentials.
159  */
160 
161 #define RTC_REG_XPRAM           14
162 #define RTC_CMD_XPRAM_READ      (RTC_CMD_READ(RTC_REG_XPRAM) << 8)
163 #define RTC_CMD_XPRAM_WRITE     (RTC_CMD_WRITE(RTC_REG_XPRAM) << 8)
164 #define RTC_CMD_XPRAM_ARG(a)    (((a & 0xE0) << 3) | ((a & 0x1F) << 2))
165 
166 /*
167  * Execute a VIA PRAM/RTC command. For read commands
168  * data should point to a one-byte buffer for the
169  * resulting data. For write commands it should point
170  * to the data byte to for the command.
171  *
172  * This function disables all interrupts while running.
173  */
174 
via_rtc_command(int command,__u8 * data)175 static void via_rtc_command(int command, __u8 *data)
176 {
177 	unsigned long flags;
178 	int is_read;
179 
180 	local_irq_save(flags);
181 
182 	/* The least significant bits must be 0b01 according to Inside Mac */
183 
184 	command = (command & ~3) | 1;
185 
186 	/* Enable the RTC and make sure the strobe line is high */
187 
188 	via1[vBufB] = (via1[vBufB] | VIA1B_vRTCClk) & ~VIA1B_vRTCEnb;
189 
190 	if (command & 0xFF00) {		/* extended (two-byte) command */
191 		via_rtc_send((command & 0xFF00) >> 8);
192 		via_rtc_send(command & 0xFF);
193 		is_read = command & (RTC_FLG_READ << 8);
194 	} else {			/* one-byte command */
195 		via_rtc_send(command);
196 		is_read = command & RTC_FLG_READ;
197 	}
198 	if (is_read) {
199 		*data = via_rtc_recv();
200 	} else {
201 		via_rtc_send(*data);
202 	}
203 
204 	/* All done, disable the RTC */
205 
206 	via1[vBufB] |= VIA1B_vRTCEnb;
207 
208 	local_irq_restore(flags);
209 }
210 
211 #if IS_ENABLED(CONFIG_NVRAM)
via_pram_read_byte(int offset)212 static unsigned char via_pram_read_byte(int offset)
213 {
214 	unsigned char temp;
215 
216 	via_rtc_command(RTC_CMD_XPRAM_READ | RTC_CMD_XPRAM_ARG(offset), &temp);
217 
218 	return temp;
219 }
220 
via_pram_write_byte(unsigned char data,int offset)221 static void via_pram_write_byte(unsigned char data, int offset)
222 {
223 	unsigned char temp;
224 
225 	temp = 0x55;
226 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_WRITE_PROTECT), &temp);
227 
228 	temp = data;
229 	via_rtc_command(RTC_CMD_XPRAM_WRITE | RTC_CMD_XPRAM_ARG(offset), &temp);
230 
231 	temp = 0x55 | RTC_FLG_WRITE_PROTECT;
232 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_WRITE_PROTECT), &temp);
233 }
234 #endif /* CONFIG_NVRAM */
235 
236 /*
237  * Return the current time in seconds since January 1, 1904.
238  *
239  * This only works on machines with the VIA-based PRAM/RTC, which
240  * is basically any machine with Mac II-style ADB.
241  */
242 
via_read_time(void)243 static time64_t via_read_time(void)
244 {
245 	union {
246 		__u8 cdata[4];
247 		__u32 idata;
248 	} result, last_result;
249 	int count = 1;
250 
251 	via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_0), &last_result.cdata[3]);
252 	via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_1), &last_result.cdata[2]);
253 	via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_2), &last_result.cdata[1]);
254 	via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_3), &last_result.cdata[0]);
255 
256 	/*
257 	 * The NetBSD guys say to loop until you get the same reading
258 	 * twice in a row.
259 	 */
260 
261 	while (1) {
262 		via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_0),
263 		                &result.cdata[3]);
264 		via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_1),
265 		                &result.cdata[2]);
266 		via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_2),
267 		                &result.cdata[1]);
268 		via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_3),
269 		                &result.cdata[0]);
270 
271 		if (result.idata == last_result.idata)
272 			return (time64_t)result.idata - RTC_OFFSET;
273 
274 		if (++count > 10)
275 			break;
276 
277 		last_result.idata = result.idata;
278 	}
279 
280 	pr_err("%s: failed to read a stable value; got 0x%08x then 0x%08x\n",
281 	       __func__, last_result.idata, result.idata);
282 
283 	return 0;
284 }
285 
286 /*
287  * Set the current time to a number of seconds since January 1, 1904.
288  *
289  * This only works on machines with the VIA-based PRAM/RTC, which
290  * is basically any machine with Mac II-style ADB.
291  */
292 
via_set_rtc_time(struct rtc_time * tm)293 static void via_set_rtc_time(struct rtc_time *tm)
294 {
295 	union {
296 		__u8 cdata[4];
297 		__u32 idata;
298 	} data;
299 	__u8 temp;
300 	time64_t time;
301 
302 	time = mktime64(tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
303 	                tm->tm_hour, tm->tm_min, tm->tm_sec);
304 
305 	/* Clear the write protect bit */
306 
307 	temp = 0x55;
308 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_WRITE_PROTECT), &temp);
309 
310 	data.idata = lower_32_bits(time + RTC_OFFSET);
311 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_SECONDS_0), &data.cdata[3]);
312 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_SECONDS_1), &data.cdata[2]);
313 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_SECONDS_2), &data.cdata[1]);
314 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_SECONDS_3), &data.cdata[0]);
315 
316 	/* Set the write protect bit */
317 
318 	temp = 0x55 | RTC_FLG_WRITE_PROTECT;
319 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_WRITE_PROTECT), &temp);
320 }
321 
via_shutdown(void)322 static void via_shutdown(void)
323 {
324 	if (rbv_present) {
325 		via2[rBufB] &= ~0x04;
326 	} else {
327 		/* Direction of vDirB is output */
328 		via2[vDirB] |= 0x04;
329 		/* Send a value of 0 on that line */
330 		via2[vBufB] &= ~0x04;
331 		mdelay(1000);
332 	}
333 }
334 
oss_shutdown(void)335 static void oss_shutdown(void)
336 {
337 	oss->rom_ctrl = OSS_POWEROFF;
338 }
339 
340 #ifdef CONFIG_ADB_CUDA
cuda_restart(void)341 static void cuda_restart(void)
342 {
343 	struct adb_request req;
344 
345 	if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_RESET_SYSTEM) < 0)
346 		return;
347 	while (!req.complete)
348 		cuda_poll();
349 }
350 
cuda_shutdown(void)351 static void cuda_shutdown(void)
352 {
353 	struct adb_request req;
354 
355 	if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_POWERDOWN) < 0)
356 		return;
357 
358 	/* Avoid infinite polling loop when PSU is not under Cuda control */
359 	switch (macintosh_config->ident) {
360 	case MAC_MODEL_C660:
361 	case MAC_MODEL_Q605:
362 	case MAC_MODEL_Q605_ACC:
363 	case MAC_MODEL_P475:
364 	case MAC_MODEL_P475F:
365 		return;
366 	}
367 
368 	while (!req.complete)
369 		cuda_poll();
370 }
371 #endif /* CONFIG_ADB_CUDA */
372 
373 /*
374  *-------------------------------------------------------------------
375  * Below this point are the generic routines; they'll dispatch to the
376  * correct routine for the hardware on which we're running.
377  *-------------------------------------------------------------------
378  */
379 
380 #if IS_ENABLED(CONFIG_NVRAM)
mac_pram_read_byte(int addr)381 unsigned char mac_pram_read_byte(int addr)
382 {
383 	switch (macintosh_config->adb_type) {
384 	case MAC_ADB_IOP:
385 	case MAC_ADB_II:
386 	case MAC_ADB_PB1:
387 		return via_pram_read_byte(addr);
388 #ifdef CONFIG_ADB_CUDA
389 	case MAC_ADB_EGRET:
390 	case MAC_ADB_CUDA:
391 		return cuda_pram_read_byte(addr);
392 #endif
393 #ifdef CONFIG_ADB_PMU
394 	case MAC_ADB_PB2:
395 		return pmu_pram_read_byte(addr);
396 #endif
397 	default:
398 		return 0xFF;
399 	}
400 }
401 
mac_pram_write_byte(unsigned char val,int addr)402 void mac_pram_write_byte(unsigned char val, int addr)
403 {
404 	switch (macintosh_config->adb_type) {
405 	case MAC_ADB_IOP:
406 	case MAC_ADB_II:
407 	case MAC_ADB_PB1:
408 		via_pram_write_byte(val, addr);
409 		break;
410 #ifdef CONFIG_ADB_CUDA
411 	case MAC_ADB_EGRET:
412 	case MAC_ADB_CUDA:
413 		cuda_pram_write_byte(val, addr);
414 		break;
415 #endif
416 #ifdef CONFIG_ADB_PMU
417 	case MAC_ADB_PB2:
418 		pmu_pram_write_byte(val, addr);
419 		break;
420 #endif
421 	default:
422 		break;
423 	}
424 }
425 
mac_pram_get_size(void)426 ssize_t mac_pram_get_size(void)
427 {
428 	return 256;
429 }
430 #endif /* CONFIG_NVRAM */
431 
mac_poweroff(void)432 void mac_poweroff(void)
433 {
434 	if (oss_present) {
435 		oss_shutdown();
436 	} else if (macintosh_config->adb_type == MAC_ADB_II) {
437 		via_shutdown();
438 #ifdef CONFIG_ADB_CUDA
439 	} else if (macintosh_config->adb_type == MAC_ADB_EGRET ||
440 	           macintosh_config->adb_type == MAC_ADB_CUDA) {
441 		cuda_shutdown();
442 #endif
443 #ifdef CONFIG_ADB_PMU
444 	} else if (macintosh_config->adb_type == MAC_ADB_PB2) {
445 		pmu_shutdown();
446 #endif
447 	}
448 
449 	pr_crit("It is now safe to turn off your Macintosh.\n");
450 	local_irq_disable();
451 	while(1);
452 }
453 
mac_reset(void)454 void mac_reset(void)
455 {
456 #ifdef CONFIG_ADB_CUDA
457 	if (macintosh_config->adb_type == MAC_ADB_EGRET ||
458 	    macintosh_config->adb_type == MAC_ADB_CUDA) {
459 		cuda_restart();
460 	} else
461 #endif
462 #ifdef CONFIG_ADB_PMU
463 	if (macintosh_config->adb_type == MAC_ADB_PB2) {
464 		pmu_restart();
465 	} else
466 #endif
467 	if (CPU_IS_030) {
468 		/* 030-specific reset routine.  The idea is general, but the
469 		 * specific registers to reset are '030-specific.  Until I
470 		 * have a non-030 machine, I can't test anything else.
471 		 *  -- C. Scott Ananian <cananian@alumni.princeton.edu>
472 		 */
473 
474 		unsigned long rombase = 0x40000000;
475 
476 		/* make a 1-to-1 mapping, using the transparent tran. reg. */
477 		unsigned long virt = (unsigned long) mac_reset;
478 		unsigned long phys = virt_to_phys(mac_reset);
479 		unsigned long addr = (phys&0xFF000000)|0x8777;
480 		unsigned long offset = phys-virt;
481 
482 		local_irq_disable(); /* lets not screw this up, ok? */
483 		__asm__ __volatile__(".chip 68030\n\t"
484 				     "pmove %0,%/tt0\n\t"
485 				     ".chip 68k"
486 				     : : "m" (addr));
487 		/* Now jump to physical address so we can disable MMU */
488 		__asm__ __volatile__(
489 		    ".chip 68030\n\t"
490 		    "lea %/pc@(1f),%/a0\n\t"
491 		    "addl %0,%/a0\n\t"/* fixup target address and stack ptr */
492 		    "addl %0,%/sp\n\t"
493 		    "pflusha\n\t"
494 		    "jmp %/a0@\n\t" /* jump into physical memory */
495 		    "0:.long 0\n\t" /* a constant zero. */
496 		    /* OK.  Now reset everything and jump to reset vector. */
497 		    "1:\n\t"
498 		    "lea %/pc@(0b),%/a0\n\t"
499 		    "pmove %/a0@, %/tc\n\t" /* disable mmu */
500 		    "pmove %/a0@, %/tt0\n\t" /* disable tt0 */
501 		    "pmove %/a0@, %/tt1\n\t" /* disable tt1 */
502 		    "movel #0, %/a0\n\t"
503 		    "movec %/a0, %/vbr\n\t" /* clear vector base register */
504 		    "movec %/a0, %/cacr\n\t" /* disable caches */
505 		    "movel #0x0808,%/a0\n\t"
506 		    "movec %/a0, %/cacr\n\t" /* flush i&d caches */
507 		    "movew #0x2700,%/sr\n\t" /* set up status register */
508 		    "movel %1@(0x0),%/a0\n\t"/* load interrupt stack pointer */
509 		    "movec %/a0, %/isp\n\t"
510 		    "movel %1@(0x4),%/a0\n\t" /* load reset vector */
511 		    "reset\n\t" /* reset external devices */
512 		    "jmp %/a0@\n\t" /* jump to the reset vector */
513 		    ".chip 68k"
514 		    : : "r" (offset), "a" (rombase) : "a0");
515 	} else {
516 		/* need ROMBASE in booter */
517 		/* indeed, plus need to MAP THE ROM !! */
518 
519 		if (mac_bi_data.rombase == 0)
520 			mac_bi_data.rombase = 0x40800000;
521 
522 		/* works on some */
523 		rom_reset = (void *)(mac_bi_data.rombase + 0xa);
524 
525 		local_irq_disable();
526 		rom_reset();
527 	}
528 
529 	/* should never get here */
530 	pr_crit("Restart failed. Please restart manually.\n");
531 	local_irq_disable();
532 	while(1);
533 }
534 
535 /*
536  * This function translates seconds since 1970 into a proper date.
537  *
538  * Algorithm cribbed from glibc2.1, __offtime().
539  *
540  * This is roughly same as rtc_time64_to_tm(), which we should probably
541  * use here, but it's only available when CONFIG_RTC_LIB is enabled.
542  */
543 #define SECS_PER_MINUTE (60)
544 #define SECS_PER_HOUR  (SECS_PER_MINUTE * 60)
545 #define SECS_PER_DAY   (SECS_PER_HOUR * 24)
546 
unmktime(time64_t time,long offset,int * yearp,int * monp,int * dayp,int * hourp,int * minp,int * secp)547 static void unmktime(time64_t time, long offset,
548 		     int *yearp, int *monp, int *dayp,
549 		     int *hourp, int *minp, int *secp)
550 {
551         /* How many days come before each month (0-12).  */
552 	static const unsigned short int __mon_yday[2][13] =
553 	{
554 		/* Normal years.  */
555 		{ 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
556 		/* Leap years.  */
557 		{ 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
558 	};
559 	int days, rem, y, wday;
560 	const unsigned short int *ip;
561 
562 	days = div_u64_rem(time, SECS_PER_DAY, &rem);
563 	rem += offset;
564 	while (rem < 0) {
565 		rem += SECS_PER_DAY;
566 		--days;
567 	}
568 	while (rem >= SECS_PER_DAY) {
569 		rem -= SECS_PER_DAY;
570 		++days;
571 	}
572 	*hourp = rem / SECS_PER_HOUR;
573 	rem %= SECS_PER_HOUR;
574 	*minp = rem / SECS_PER_MINUTE;
575 	*secp = rem % SECS_PER_MINUTE;
576 	/* January 1, 1970 was a Thursday. */
577 	wday = (4 + days) % 7; /* Day in the week. Not currently used */
578 	if (wday < 0) wday += 7;
579 	y = 1970;
580 
581 #define DIV(a, b) ((a) / (b) - ((a) % (b) < 0))
582 #define LEAPS_THRU_END_OF(y) (DIV (y, 4) - DIV (y, 100) + DIV (y, 400))
583 #define __isleap(year)	\
584   ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
585 
586 	while (days < 0 || days >= (__isleap (y) ? 366 : 365))
587 	{
588 		/* Guess a corrected year, assuming 365 days per year.  */
589 		long int yg = y + days / 365 - (days % 365 < 0);
590 
591 		/* Adjust DAYS and Y to match the guessed year.  */
592 		days -= (yg - y) * 365 +
593 			LEAPS_THRU_END_OF(yg - 1) - LEAPS_THRU_END_OF(y - 1);
594 		y = yg;
595 	}
596 	*yearp = y - 1900;
597 	ip = __mon_yday[__isleap(y)];
598 	for (y = 11; days < (long int) ip[y]; --y)
599 		continue;
600 	days -= ip[y];
601 	*monp = y;
602 	*dayp = days + 1; /* day in the month */
603 	return;
604 }
605 
606 /*
607  * Read/write the hardware clock.
608  */
609 
mac_hwclk(int op,struct rtc_time * t)610 int mac_hwclk(int op, struct rtc_time *t)
611 {
612 	time64_t now;
613 
614 	if (!op) { /* read */
615 		switch (macintosh_config->adb_type) {
616 		case MAC_ADB_IOP:
617 		case MAC_ADB_II:
618 		case MAC_ADB_PB1:
619 			now = via_read_time();
620 			break;
621 #ifdef CONFIG_ADB_CUDA
622 		case MAC_ADB_EGRET:
623 		case MAC_ADB_CUDA:
624 			now = cuda_get_time();
625 			break;
626 #endif
627 #ifdef CONFIG_ADB_PMU
628 		case MAC_ADB_PB2:
629 			now = pmu_get_time();
630 			break;
631 #endif
632 		default:
633 			now = 0;
634 		}
635 
636 		t->tm_wday = 0;
637 		unmktime(now, 0,
638 			 &t->tm_year, &t->tm_mon, &t->tm_mday,
639 			 &t->tm_hour, &t->tm_min, &t->tm_sec);
640 		pr_debug("%s: read %ptR\n", __func__, t);
641 	} else { /* write */
642 		pr_debug("%s: tried to write %ptR\n", __func__, t);
643 
644 		switch (macintosh_config->adb_type) {
645 		case MAC_ADB_IOP:
646 		case MAC_ADB_II:
647 		case MAC_ADB_PB1:
648 			via_set_rtc_time(t);
649 			break;
650 #ifdef CONFIG_ADB_CUDA
651 		case MAC_ADB_EGRET:
652 		case MAC_ADB_CUDA:
653 			cuda_set_rtc_time(t);
654 			break;
655 #endif
656 #ifdef CONFIG_ADB_PMU
657 		case MAC_ADB_PB2:
658 			pmu_set_rtc_time(t);
659 			break;
660 #endif
661 		default:
662 			return -ENODEV;
663 		}
664 	}
665 	return 0;
666 }
667