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 /*
29  * Offset between Unix time (1970-based) and Mac time (1904-based). Cuda and PMU
30  * times wrap in 2040. If we need to handle later times, the read_time functions
31  * need to be changed to interpret wrapped times as post-2040.
32  */
33 
34 #define RTC_OFFSET 2082844800
35 
36 static void (*rom_reset)(void);
37 
38 #if IS_ENABLED(CONFIG_NVRAM)
39 #ifdef CONFIG_ADB_CUDA
cuda_pram_read_byte(int offset)40 static unsigned char cuda_pram_read_byte(int offset)
41 {
42 	struct adb_request req;
43 
44 	if (cuda_request(&req, NULL, 4, CUDA_PACKET, CUDA_GET_PRAM,
45 			 (offset >> 8) & 0xFF, offset & 0xFF) < 0)
46 		return 0;
47 	while (!req.complete)
48 		cuda_poll();
49 	return req.reply[3];
50 }
51 
cuda_pram_write_byte(unsigned char data,int offset)52 static void cuda_pram_write_byte(unsigned char data, int offset)
53 {
54 	struct adb_request req;
55 
56 	if (cuda_request(&req, NULL, 5, CUDA_PACKET, CUDA_SET_PRAM,
57 			 (offset >> 8) & 0xFF, offset & 0xFF, data) < 0)
58 		return;
59 	while (!req.complete)
60 		cuda_poll();
61 }
62 #endif /* CONFIG_ADB_CUDA */
63 
64 #ifdef CONFIG_ADB_PMU
pmu_pram_read_byte(int offset)65 static unsigned char pmu_pram_read_byte(int offset)
66 {
67 	struct adb_request req;
68 
69 	if (pmu_request(&req, NULL, 3, PMU_READ_XPRAM,
70 	                offset & 0xFF, 1) < 0)
71 		return 0;
72 	pmu_wait_complete(&req);
73 
74 	return req.reply[0];
75 }
76 
pmu_pram_write_byte(unsigned char data,int offset)77 static void pmu_pram_write_byte(unsigned char data, int offset)
78 {
79 	struct adb_request req;
80 
81 	if (pmu_request(&req, NULL, 4, PMU_WRITE_XPRAM,
82 	                offset & 0xFF, 1, data) < 0)
83 		return;
84 	pmu_wait_complete(&req);
85 }
86 #endif /* CONFIG_ADB_PMU */
87 #endif /* CONFIG_NVRAM */
88 
89 /*
90  * VIA PRAM/RTC access routines
91  *
92  * Must be called with interrupts disabled and
93  * the RTC should be enabled.
94  */
95 
via_rtc_recv(void)96 static __u8 via_rtc_recv(void)
97 {
98 	int i, reg;
99 	__u8 data;
100 
101 	reg = via1[vBufB] & ~VIA1B_vRTCClk;
102 
103 	/* Set the RTC data line to be an input. */
104 
105 	via1[vDirB] &= ~VIA1B_vRTCData;
106 
107 	/* The bits of the byte come out in MSB order */
108 
109 	data = 0;
110 	for (i = 0 ; i < 8 ; i++) {
111 		via1[vBufB] = reg;
112 		via1[vBufB] = reg | VIA1B_vRTCClk;
113 		data = (data << 1) | (via1[vBufB] & VIA1B_vRTCData);
114 	}
115 
116 	/* Return RTC data line to output state */
117 
118 	via1[vDirB] |= VIA1B_vRTCData;
119 
120 	return data;
121 }
122 
via_rtc_send(__u8 data)123 static void via_rtc_send(__u8 data)
124 {
125 	int i, reg, bit;
126 
127 	reg = via1[vBufB] & ~(VIA1B_vRTCClk | VIA1B_vRTCData);
128 
129 	/* The bits of the byte go in in MSB order */
130 
131 	for (i = 0 ; i < 8 ; i++) {
132 		bit = data & 0x80? 1 : 0;
133 		data <<= 1;
134 		via1[vBufB] = reg | bit;
135 		via1[vBufB] = reg | bit | VIA1B_vRTCClk;
136 	}
137 }
138 
139 /*
140  * These values can be found in Inside Macintosh vol. III ch. 2
141  * which has a description of the RTC chip in the original Mac.
142  */
143 
144 #define RTC_FLG_READ            BIT(7)
145 #define RTC_FLG_WRITE_PROTECT   BIT(7)
146 #define RTC_CMD_READ(r)         (RTC_FLG_READ | (r << 2))
147 #define RTC_CMD_WRITE(r)        (r << 2)
148 #define RTC_REG_SECONDS_0       0
149 #define RTC_REG_SECONDS_1       1
150 #define RTC_REG_SECONDS_2       2
151 #define RTC_REG_SECONDS_3       3
152 #define RTC_REG_WRITE_PROTECT   13
153 
154 /*
155  * Inside Mac has no information about two-byte RTC commands but
156  * the MAME/MESS source code has the essentials.
157  */
158 
159 #define RTC_REG_XPRAM           14
160 #define RTC_CMD_XPRAM_READ      (RTC_CMD_READ(RTC_REG_XPRAM) << 8)
161 #define RTC_CMD_XPRAM_WRITE     (RTC_CMD_WRITE(RTC_REG_XPRAM) << 8)
162 #define RTC_CMD_XPRAM_ARG(a)    (((a & 0xE0) << 3) | ((a & 0x1F) << 2))
163 
164 /*
165  * Execute a VIA PRAM/RTC command. For read commands
166  * data should point to a one-byte buffer for the
167  * resulting data. For write commands it should point
168  * to the data byte to for the command.
169  *
170  * This function disables all interrupts while running.
171  */
172 
via_rtc_command(int command,__u8 * data)173 static void via_rtc_command(int command, __u8 *data)
174 {
175 	unsigned long flags;
176 	int is_read;
177 
178 	local_irq_save(flags);
179 
180 	/* The least significant bits must be 0b01 according to Inside Mac */
181 
182 	command = (command & ~3) | 1;
183 
184 	/* Enable the RTC and make sure the strobe line is high */
185 
186 	via1[vBufB] = (via1[vBufB] | VIA1B_vRTCClk) & ~VIA1B_vRTCEnb;
187 
188 	if (command & 0xFF00) {		/* extended (two-byte) command */
189 		via_rtc_send((command & 0xFF00) >> 8);
190 		via_rtc_send(command & 0xFF);
191 		is_read = command & (RTC_FLG_READ << 8);
192 	} else {			/* one-byte command */
193 		via_rtc_send(command);
194 		is_read = command & RTC_FLG_READ;
195 	}
196 	if (is_read) {
197 		*data = via_rtc_recv();
198 	} else {
199 		via_rtc_send(*data);
200 	}
201 
202 	/* All done, disable the RTC */
203 
204 	via1[vBufB] |= VIA1B_vRTCEnb;
205 
206 	local_irq_restore(flags);
207 }
208 
209 #if IS_ENABLED(CONFIG_NVRAM)
via_pram_read_byte(int offset)210 static unsigned char via_pram_read_byte(int offset)
211 {
212 	unsigned char temp;
213 
214 	via_rtc_command(RTC_CMD_XPRAM_READ | RTC_CMD_XPRAM_ARG(offset), &temp);
215 
216 	return temp;
217 }
218 
via_pram_write_byte(unsigned char data,int offset)219 static void via_pram_write_byte(unsigned char data, int offset)
220 {
221 	unsigned char temp;
222 
223 	temp = 0x55;
224 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_WRITE_PROTECT), &temp);
225 
226 	temp = data;
227 	via_rtc_command(RTC_CMD_XPRAM_WRITE | RTC_CMD_XPRAM_ARG(offset), &temp);
228 
229 	temp = 0x55 | RTC_FLG_WRITE_PROTECT;
230 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_WRITE_PROTECT), &temp);
231 }
232 #endif /* CONFIG_NVRAM */
233 
234 /*
235  * Return the current time in seconds since January 1, 1904.
236  *
237  * This only works on machines with the VIA-based PRAM/RTC, which
238  * is basically any machine with Mac II-style ADB.
239  */
240 
via_read_time(void)241 static time64_t via_read_time(void)
242 {
243 	union {
244 		__u8 cdata[4];
245 		__u32 idata;
246 	} result, last_result;
247 	int count = 1;
248 
249 	via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_0), &last_result.cdata[3]);
250 	via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_1), &last_result.cdata[2]);
251 	via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_2), &last_result.cdata[1]);
252 	via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_3), &last_result.cdata[0]);
253 
254 	/*
255 	 * The NetBSD guys say to loop until you get the same reading
256 	 * twice in a row.
257 	 */
258 
259 	while (1) {
260 		via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_0),
261 		                &result.cdata[3]);
262 		via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_1),
263 		                &result.cdata[2]);
264 		via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_2),
265 		                &result.cdata[1]);
266 		via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_3),
267 		                &result.cdata[0]);
268 
269 		if (result.idata == last_result.idata)
270 			return (time64_t)result.idata - RTC_OFFSET;
271 
272 		if (++count > 10)
273 			break;
274 
275 		last_result.idata = result.idata;
276 	}
277 
278 	pr_err("%s: failed to read a stable value; got 0x%08x then 0x%08x\n",
279 	       __func__, last_result.idata, result.idata);
280 
281 	return 0;
282 }
283 
284 /*
285  * Set the current time to a number of seconds since January 1, 1904.
286  *
287  * This only works on machines with the VIA-based PRAM/RTC, which
288  * is basically any machine with Mac II-style ADB.
289  */
290 
via_set_rtc_time(struct rtc_time * tm)291 static void via_set_rtc_time(struct rtc_time *tm)
292 {
293 	union {
294 		__u8 cdata[4];
295 		__u32 idata;
296 	} data;
297 	__u8 temp;
298 	time64_t time;
299 
300 	time = mktime64(tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
301 	                tm->tm_hour, tm->tm_min, tm->tm_sec);
302 
303 	/* Clear the write protect bit */
304 
305 	temp = 0x55;
306 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_WRITE_PROTECT), &temp);
307 
308 	data.idata = lower_32_bits(time + RTC_OFFSET);
309 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_SECONDS_0), &data.cdata[3]);
310 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_SECONDS_1), &data.cdata[2]);
311 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_SECONDS_2), &data.cdata[1]);
312 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_SECONDS_3), &data.cdata[0]);
313 
314 	/* Set the write protect bit */
315 
316 	temp = 0x55 | RTC_FLG_WRITE_PROTECT;
317 	via_rtc_command(RTC_CMD_WRITE(RTC_REG_WRITE_PROTECT), &temp);
318 }
319 
via_shutdown(void)320 static void via_shutdown(void)
321 {
322 	if (rbv_present) {
323 		via2[rBufB] &= ~0x04;
324 	} else {
325 		/* Direction of vDirB is output */
326 		via2[vDirB] |= 0x04;
327 		/* Send a value of 0 on that line */
328 		via2[vBufB] &= ~0x04;
329 		mdelay(1000);
330 	}
331 }
332 
oss_shutdown(void)333 static void oss_shutdown(void)
334 {
335 	oss->rom_ctrl = OSS_POWEROFF;
336 }
337 
338 #ifdef CONFIG_ADB_CUDA
cuda_restart(void)339 static void cuda_restart(void)
340 {
341 	struct adb_request req;
342 
343 	if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_RESET_SYSTEM) < 0)
344 		return;
345 	while (!req.complete)
346 		cuda_poll();
347 }
348 
cuda_shutdown(void)349 static void cuda_shutdown(void)
350 {
351 	struct adb_request req;
352 
353 	if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_POWERDOWN) < 0)
354 		return;
355 
356 	/* Avoid infinite polling loop when PSU is not under Cuda control */
357 	switch (macintosh_config->ident) {
358 	case MAC_MODEL_C660:
359 	case MAC_MODEL_Q605:
360 	case MAC_MODEL_Q605_ACC:
361 	case MAC_MODEL_P475:
362 	case MAC_MODEL_P475F:
363 		return;
364 	}
365 
366 	while (!req.complete)
367 		cuda_poll();
368 }
369 #endif /* CONFIG_ADB_CUDA */
370 
371 /*
372  *-------------------------------------------------------------------
373  * Below this point are the generic routines; they'll dispatch to the
374  * correct routine for the hardware on which we're running.
375  *-------------------------------------------------------------------
376  */
377 
378 #if IS_ENABLED(CONFIG_NVRAM)
mac_pram_read_byte(int addr)379 unsigned char mac_pram_read_byte(int addr)
380 {
381 	switch (macintosh_config->adb_type) {
382 	case MAC_ADB_IOP:
383 	case MAC_ADB_II:
384 	case MAC_ADB_PB1:
385 		return via_pram_read_byte(addr);
386 #ifdef CONFIG_ADB_CUDA
387 	case MAC_ADB_EGRET:
388 	case MAC_ADB_CUDA:
389 		return cuda_pram_read_byte(addr);
390 #endif
391 #ifdef CONFIG_ADB_PMU
392 	case MAC_ADB_PB2:
393 		return pmu_pram_read_byte(addr);
394 #endif
395 	default:
396 		return 0xFF;
397 	}
398 }
399 
mac_pram_write_byte(unsigned char val,int addr)400 void mac_pram_write_byte(unsigned char val, int addr)
401 {
402 	switch (macintosh_config->adb_type) {
403 	case MAC_ADB_IOP:
404 	case MAC_ADB_II:
405 	case MAC_ADB_PB1:
406 		via_pram_write_byte(val, addr);
407 		break;
408 #ifdef CONFIG_ADB_CUDA
409 	case MAC_ADB_EGRET:
410 	case MAC_ADB_CUDA:
411 		cuda_pram_write_byte(val, addr);
412 		break;
413 #endif
414 #ifdef CONFIG_ADB_PMU
415 	case MAC_ADB_PB2:
416 		pmu_pram_write_byte(val, addr);
417 		break;
418 #endif
419 	default:
420 		break;
421 	}
422 }
423 
mac_pram_get_size(void)424 ssize_t mac_pram_get_size(void)
425 {
426 	return 256;
427 }
428 #endif /* CONFIG_NVRAM */
429 
mac_poweroff(void)430 void mac_poweroff(void)
431 {
432 	if (oss_present) {
433 		oss_shutdown();
434 	} else if (macintosh_config->adb_type == MAC_ADB_II) {
435 		via_shutdown();
436 #ifdef CONFIG_ADB_CUDA
437 	} else if (macintosh_config->adb_type == MAC_ADB_EGRET ||
438 	           macintosh_config->adb_type == MAC_ADB_CUDA) {
439 		cuda_shutdown();
440 #endif
441 #ifdef CONFIG_ADB_PMU
442 	} else if (macintosh_config->adb_type == MAC_ADB_PB2) {
443 		pmu_shutdown();
444 #endif
445 	}
446 
447 	pr_crit("It is now safe to turn off your Macintosh.\n");
448 	local_irq_disable();
449 	while(1);
450 }
451 
mac_reset(void)452 void mac_reset(void)
453 {
454 	if (macintosh_config->adb_type == MAC_ADB_II &&
455 	    macintosh_config->ident != MAC_MODEL_SE30) {
456 		/* need ROMBASE in booter */
457 		/* indeed, plus need to MAP THE ROM !! */
458 
459 		if (mac_bi_data.rombase == 0)
460 			mac_bi_data.rombase = 0x40800000;
461 
462 		/* works on some */
463 		rom_reset = (void *) (mac_bi_data.rombase + 0xa);
464 
465 		local_irq_disable();
466 		rom_reset();
467 #ifdef CONFIG_ADB_CUDA
468 	} else if (macintosh_config->adb_type == MAC_ADB_EGRET ||
469 	           macintosh_config->adb_type == MAC_ADB_CUDA) {
470 		cuda_restart();
471 #endif
472 #ifdef CONFIG_ADB_PMU
473 	} else if (macintosh_config->adb_type == MAC_ADB_PB2) {
474 		pmu_restart();
475 #endif
476 	} else if (CPU_IS_030) {
477 
478 		/* 030-specific reset routine.  The idea is general, but the
479 		 * specific registers to reset are '030-specific.  Until I
480 		 * have a non-030 machine, I can't test anything else.
481 		 *  -- C. Scott Ananian <cananian@alumni.princeton.edu>
482 		 */
483 
484 		unsigned long rombase = 0x40000000;
485 
486 		/* make a 1-to-1 mapping, using the transparent tran. reg. */
487 		unsigned long virt = (unsigned long) mac_reset;
488 		unsigned long phys = virt_to_phys(mac_reset);
489 		unsigned long addr = (phys&0xFF000000)|0x8777;
490 		unsigned long offset = phys-virt;
491 
492 		local_irq_disable(); /* lets not screw this up, ok? */
493 		__asm__ __volatile__(".chip 68030\n\t"
494 				     "pmove %0,%/tt0\n\t"
495 				     ".chip 68k"
496 				     : : "m" (addr));
497 		/* Now jump to physical address so we can disable MMU */
498 		__asm__ __volatile__(
499 		    ".chip 68030\n\t"
500 		    "lea %/pc@(1f),%/a0\n\t"
501 		    "addl %0,%/a0\n\t"/* fixup target address and stack ptr */
502 		    "addl %0,%/sp\n\t"
503 		    "pflusha\n\t"
504 		    "jmp %/a0@\n\t" /* jump into physical memory */
505 		    "0:.long 0\n\t" /* a constant zero. */
506 		    /* OK.  Now reset everything and jump to reset vector. */
507 		    "1:\n\t"
508 		    "lea %/pc@(0b),%/a0\n\t"
509 		    "pmove %/a0@, %/tc\n\t" /* disable mmu */
510 		    "pmove %/a0@, %/tt0\n\t" /* disable tt0 */
511 		    "pmove %/a0@, %/tt1\n\t" /* disable tt1 */
512 		    "movel #0, %/a0\n\t"
513 		    "movec %/a0, %/vbr\n\t" /* clear vector base register */
514 		    "movec %/a0, %/cacr\n\t" /* disable caches */
515 		    "movel #0x0808,%/a0\n\t"
516 		    "movec %/a0, %/cacr\n\t" /* flush i&d caches */
517 		    "movew #0x2700,%/sr\n\t" /* set up status register */
518 		    "movel %1@(0x0),%/a0\n\t"/* load interrupt stack pointer */
519 		    "movec %/a0, %/isp\n\t"
520 		    "movel %1@(0x4),%/a0\n\t" /* load reset vector */
521 		    "reset\n\t" /* reset external devices */
522 		    "jmp %/a0@\n\t" /* jump to the reset vector */
523 		    ".chip 68k"
524 		    : : "r" (offset), "a" (rombase) : "a0");
525 	}
526 
527 	/* should never get here */
528 	pr_crit("Restart failed. Please restart manually.\n");
529 	local_irq_disable();
530 	while(1);
531 }
532 
533 /*
534  * This function translates seconds since 1970 into a proper date.
535  *
536  * Algorithm cribbed from glibc2.1, __offtime().
537  *
538  * This is roughly same as rtc_time64_to_tm(), which we should probably
539  * use here, but it's only available when CONFIG_RTC_LIB is enabled.
540  */
541 #define SECS_PER_MINUTE (60)
542 #define SECS_PER_HOUR  (SECS_PER_MINUTE * 60)
543 #define SECS_PER_DAY   (SECS_PER_HOUR * 24)
544 
unmktime(time64_t time,long offset,int * yearp,int * monp,int * dayp,int * hourp,int * minp,int * secp)545 static void unmktime(time64_t time, long offset,
546 		     int *yearp, int *monp, int *dayp,
547 		     int *hourp, int *minp, int *secp)
548 {
549         /* How many days come before each month (0-12).  */
550 	static const unsigned short int __mon_yday[2][13] =
551 	{
552 		/* Normal years.  */
553 		{ 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
554 		/* Leap years.  */
555 		{ 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
556 	};
557 	int days, rem, y, wday, yday;
558 	const unsigned short int *ip;
559 
560 	days = div_u64_rem(time, SECS_PER_DAY, &rem);
561 	rem += offset;
562 	while (rem < 0) {
563 		rem += SECS_PER_DAY;
564 		--days;
565 	}
566 	while (rem >= SECS_PER_DAY) {
567 		rem -= SECS_PER_DAY;
568 		++days;
569 	}
570 	*hourp = rem / SECS_PER_HOUR;
571 	rem %= SECS_PER_HOUR;
572 	*minp = rem / SECS_PER_MINUTE;
573 	*secp = rem % SECS_PER_MINUTE;
574 	/* January 1, 1970 was a Thursday. */
575 	wday = (4 + days) % 7; /* Day in the week. Not currently used */
576 	if (wday < 0) wday += 7;
577 	y = 1970;
578 
579 #define DIV(a, b) ((a) / (b) - ((a) % (b) < 0))
580 #define LEAPS_THRU_END_OF(y) (DIV (y, 4) - DIV (y, 100) + DIV (y, 400))
581 #define __isleap(year)	\
582   ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
583 
584 	while (days < 0 || days >= (__isleap (y) ? 366 : 365))
585 	{
586 		/* Guess a corrected year, assuming 365 days per year.  */
587 		long int yg = y + days / 365 - (days % 365 < 0);
588 
589 		/* Adjust DAYS and Y to match the guessed year.  */
590 		days -= (yg - y) * 365 +
591 			LEAPS_THRU_END_OF(yg - 1) - LEAPS_THRU_END_OF(y - 1);
592 		y = yg;
593 	}
594 	*yearp = y - 1900;
595 	yday = days; /* day in the year.  Not currently used. */
596 	ip = __mon_yday[__isleap(y)];
597 	for (y = 11; days < (long int) ip[y]; --y)
598 		continue;
599 	days -= ip[y];
600 	*monp = y;
601 	*dayp = days + 1; /* day in the month */
602 	return;
603 }
604 
605 /*
606  * Read/write the hardware clock.
607  */
608 
mac_hwclk(int op,struct rtc_time * t)609 int mac_hwclk(int op, struct rtc_time *t)
610 {
611 	time64_t now;
612 
613 	if (!op) { /* read */
614 		switch (macintosh_config->adb_type) {
615 		case MAC_ADB_IOP:
616 		case MAC_ADB_II:
617 		case MAC_ADB_PB1:
618 			now = via_read_time();
619 			break;
620 #ifdef CONFIG_ADB_CUDA
621 		case MAC_ADB_EGRET:
622 		case MAC_ADB_CUDA:
623 			now = cuda_get_time();
624 			break;
625 #endif
626 #ifdef CONFIG_ADB_PMU
627 		case MAC_ADB_PB2:
628 			now = pmu_get_time();
629 			break;
630 #endif
631 		default:
632 			now = 0;
633 		}
634 
635 		t->tm_wday = 0;
636 		unmktime(now, 0,
637 			 &t->tm_year, &t->tm_mon, &t->tm_mday,
638 			 &t->tm_hour, &t->tm_min, &t->tm_sec);
639 		pr_debug("%s: read %ptR\n", __func__, t);
640 	} else { /* write */
641 		pr_debug("%s: tried to write %ptR\n", __func__, t);
642 
643 		switch (macintosh_config->adb_type) {
644 		case MAC_ADB_IOP:
645 		case MAC_ADB_II:
646 		case MAC_ADB_PB1:
647 			via_set_rtc_time(t);
648 			break;
649 #ifdef CONFIG_ADB_CUDA
650 		case MAC_ADB_EGRET:
651 		case MAC_ADB_CUDA:
652 			cuda_set_rtc_time(t);
653 			break;
654 #endif
655 #ifdef CONFIG_ADB_PMU
656 		case MAC_ADB_PB2:
657 			pmu_set_rtc_time(t);
658 			break;
659 #endif
660 		default:
661 			return -ENODEV;
662 		}
663 	}
664 	return 0;
665 }
666