xref: /openbmc/linux/arch/m68k/mac/misc.c (revision ab77eb4c)
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/segment.h>
22 #include <asm/setup.h>
23 #include <asm/macintosh.h>
24 #include <asm/mac_via.h>
25 #include <asm/mac_oss.h>
26 
27 #include <asm/machdep.h>
28 
29 /*
30  * Offset between Unix time (1970-based) and Mac time (1904-based). Cuda and PMU
31  * times wrap in 2040. If we need to handle later times, the read_time functions
32  * need to be changed to interpret wrapped times as post-2040.
33  */
34 
35 #define RTC_OFFSET 2082844800
36 
37 static void (*rom_reset)(void);
38 
39 #ifdef CONFIG_ADB_CUDA
40 static time64_t cuda_read_time(void)
41 {
42 	struct adb_request req;
43 	time64_t time;
44 
45 	if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME) < 0)
46 		return 0;
47 	while (!req.complete)
48 		cuda_poll();
49 
50 	time = (u32)((req.reply[3] << 24) | (req.reply[4] << 16) |
51 		     (req.reply[5] << 8) | req.reply[6]);
52 
53 	return time - RTC_OFFSET;
54 }
55 
56 static void cuda_write_time(time64_t time)
57 {
58 	struct adb_request req;
59 	u32 data = lower_32_bits(time + RTC_OFFSET);
60 
61 	if (cuda_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME,
62 			 (data >> 24) & 0xFF, (data >> 16) & 0xFF,
63 			 (data >> 8) & 0xFF, data & 0xFF) < 0)
64 		return;
65 	while (!req.complete)
66 		cuda_poll();
67 }
68 
69 static __u8 cuda_read_pram(int offset)
70 {
71 	struct adb_request req;
72 
73 	if (cuda_request(&req, NULL, 4, CUDA_PACKET, CUDA_GET_PRAM,
74 			 (offset >> 8) & 0xFF, offset & 0xFF) < 0)
75 		return 0;
76 	while (!req.complete)
77 		cuda_poll();
78 	return req.reply[3];
79 }
80 
81 static void cuda_write_pram(int offset, __u8 data)
82 {
83 	struct adb_request req;
84 
85 	if (cuda_request(&req, NULL, 5, CUDA_PACKET, CUDA_SET_PRAM,
86 			 (offset >> 8) & 0xFF, offset & 0xFF, data) < 0)
87 		return;
88 	while (!req.complete)
89 		cuda_poll();
90 }
91 #endif /* CONFIG_ADB_CUDA */
92 
93 #ifdef CONFIG_ADB_PMU
94 static time64_t pmu_read_time(void)
95 {
96 	struct adb_request req;
97 	time64_t time;
98 
99 	if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0)
100 		return 0;
101 	pmu_wait_complete(&req);
102 
103 	time = (u32)((req.reply[0] << 24) | (req.reply[1] << 16) |
104 		     (req.reply[2] << 8) | req.reply[3]);
105 
106 	return time - RTC_OFFSET;
107 }
108 
109 static void pmu_write_time(time64_t time)
110 {
111 	struct adb_request req;
112 	u32 data = lower_32_bits(time + RTC_OFFSET);
113 
114 	if (pmu_request(&req, NULL, 5, PMU_SET_RTC,
115 			(data >> 24) & 0xFF, (data >> 16) & 0xFF,
116 			(data >> 8) & 0xFF, data & 0xFF) < 0)
117 		return;
118 	pmu_wait_complete(&req);
119 }
120 
121 static __u8 pmu_read_pram(int offset)
122 {
123 	struct adb_request req;
124 
125 	if (pmu_request(&req, NULL, 3, PMU_READ_NVRAM,
126 			(offset >> 8) & 0xFF, offset & 0xFF) < 0)
127 		return 0;
128 	while (!req.complete)
129 		pmu_poll();
130 	return req.reply[3];
131 }
132 
133 static void pmu_write_pram(int offset, __u8 data)
134 {
135 	struct adb_request req;
136 
137 	if (pmu_request(&req, NULL, 4, PMU_WRITE_NVRAM,
138 			(offset >> 8) & 0xFF, offset & 0xFF, data) < 0)
139 		return;
140 	while (!req.complete)
141 		pmu_poll();
142 }
143 #endif /* CONFIG_ADB_PMU */
144 
145 /*
146  * VIA PRAM/RTC access routines
147  *
148  * Must be called with interrupts disabled and
149  * the RTC should be enabled.
150  */
151 
152 static __u8 via_pram_readbyte(void)
153 {
154 	int i, reg;
155 	__u8 data;
156 
157 	reg = via1[vBufB] & ~VIA1B_vRTCClk;
158 
159 	/* Set the RTC data line to be an input. */
160 
161 	via1[vDirB] &= ~VIA1B_vRTCData;
162 
163 	/* The bits of the byte come out in MSB order */
164 
165 	data = 0;
166 	for (i = 0 ; i < 8 ; i++) {
167 		via1[vBufB] = reg;
168 		via1[vBufB] = reg | VIA1B_vRTCClk;
169 		data = (data << 1) | (via1[vBufB] & VIA1B_vRTCData);
170 	}
171 
172 	/* Return RTC data line to output state */
173 
174 	via1[vDirB] |= VIA1B_vRTCData;
175 
176 	return data;
177 }
178 
179 static void via_pram_writebyte(__u8 data)
180 {
181 	int i, reg, bit;
182 
183 	reg = via1[vBufB] & ~(VIA1B_vRTCClk | VIA1B_vRTCData);
184 
185 	/* The bits of the byte go in in MSB order */
186 
187 	for (i = 0 ; i < 8 ; i++) {
188 		bit = data & 0x80? 1 : 0;
189 		data <<= 1;
190 		via1[vBufB] = reg | bit;
191 		via1[vBufB] = reg | bit | VIA1B_vRTCClk;
192 	}
193 }
194 
195 /*
196  * Execute a VIA PRAM/RTC command. For read commands
197  * data should point to a one-byte buffer for the
198  * resulting data. For write commands it should point
199  * to the data byte to for the command.
200  *
201  * This function disables all interrupts while running.
202  */
203 
204 static void via_pram_command(int command, __u8 *data)
205 {
206 	unsigned long flags;
207 	int is_read;
208 
209 	local_irq_save(flags);
210 
211 	/* Enable the RTC and make sure the strobe line is high */
212 
213 	via1[vBufB] = (via1[vBufB] | VIA1B_vRTCClk) & ~VIA1B_vRTCEnb;
214 
215 	if (command & 0xFF00) {		/* extended (two-byte) command */
216 		via_pram_writebyte((command & 0xFF00) >> 8);
217 		via_pram_writebyte(command & 0xFF);
218 		is_read = command & 0x8000;
219 	} else {			/* one-byte command */
220 		via_pram_writebyte(command);
221 		is_read = command & 0x80;
222 	}
223 	if (is_read) {
224 		*data = via_pram_readbyte();
225 	} else {
226 		via_pram_writebyte(*data);
227 	}
228 
229 	/* All done, disable the RTC */
230 
231 	via1[vBufB] |= VIA1B_vRTCEnb;
232 
233 	local_irq_restore(flags);
234 }
235 
236 static __u8 via_read_pram(int offset)
237 {
238 	return 0;
239 }
240 
241 static void via_write_pram(int offset, __u8 data)
242 {
243 }
244 
245 /*
246  * Return the current time in seconds since January 1, 1904.
247  *
248  * This only works on machines with the VIA-based PRAM/RTC, which
249  * is basically any machine with Mac II-style ADB.
250  */
251 
252 static time64_t via_read_time(void)
253 {
254 	union {
255 		__u8 cdata[4];
256 		__u32 idata;
257 	} result, last_result;
258 	int count = 1;
259 
260 	via_pram_command(0x81, &last_result.cdata[3]);
261 	via_pram_command(0x85, &last_result.cdata[2]);
262 	via_pram_command(0x89, &last_result.cdata[1]);
263 	via_pram_command(0x8D, &last_result.cdata[0]);
264 
265 	/*
266 	 * The NetBSD guys say to loop until you get the same reading
267 	 * twice in a row.
268 	 */
269 
270 	while (1) {
271 		via_pram_command(0x81, &result.cdata[3]);
272 		via_pram_command(0x85, &result.cdata[2]);
273 		via_pram_command(0x89, &result.cdata[1]);
274 		via_pram_command(0x8D, &result.cdata[0]);
275 
276 		if (result.idata == last_result.idata)
277 			return (time64_t)result.idata - RTC_OFFSET;
278 
279 		if (++count > 10)
280 			break;
281 
282 		last_result.idata = result.idata;
283 	}
284 
285 	pr_err("%s: failed to read a stable value; got 0x%08x then 0x%08x\n",
286 	       __func__, last_result.idata, result.idata);
287 
288 	return 0;
289 }
290 
291 /*
292  * Set the current time to a number of seconds since January 1, 1904.
293  *
294  * This only works on machines with the VIA-based PRAM/RTC, which
295  * is basically any machine with Mac II-style ADB.
296  */
297 
298 static void via_write_time(time64_t time)
299 {
300 	union {
301 		__u8 cdata[4];
302 		__u32 idata;
303 	} data;
304 	__u8 temp;
305 
306 	/* Clear the write protect bit */
307 
308 	temp = 0x55;
309 	via_pram_command(0x35, &temp);
310 
311 	data.idata = lower_32_bits(time + RTC_OFFSET);
312 	via_pram_command(0x01, &data.cdata[3]);
313 	via_pram_command(0x05, &data.cdata[2]);
314 	via_pram_command(0x09, &data.cdata[1]);
315 	via_pram_command(0x0D, &data.cdata[0]);
316 
317 	/* Set the write protect bit */
318 
319 	temp = 0xD5;
320 	via_pram_command(0x35, &temp);
321 }
322 
323 static void via_shutdown(void)
324 {
325 	if (rbv_present) {
326 		via2[rBufB] &= ~0x04;
327 	} else {
328 		/* Direction of vDirB is output */
329 		via2[vDirB] |= 0x04;
330 		/* Send a value of 0 on that line */
331 		via2[vBufB] &= ~0x04;
332 		mdelay(1000);
333 	}
334 }
335 
336 static void oss_shutdown(void)
337 {
338 	oss->rom_ctrl = OSS_POWEROFF;
339 }
340 
341 #ifdef CONFIG_ADB_CUDA
342 static void cuda_restart(void)
343 {
344 	struct adb_request req;
345 
346 	if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_RESET_SYSTEM) < 0)
347 		return;
348 	while (!req.complete)
349 		cuda_poll();
350 }
351 
352 static void cuda_shutdown(void)
353 {
354 	struct adb_request req;
355 
356 	if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_POWERDOWN) < 0)
357 		return;
358 
359 	/* Avoid infinite polling loop when PSU is not under Cuda control */
360 	switch (macintosh_config->ident) {
361 	case MAC_MODEL_C660:
362 	case MAC_MODEL_Q605:
363 	case MAC_MODEL_Q605_ACC:
364 	case MAC_MODEL_P475:
365 	case MAC_MODEL_P475F:
366 		return;
367 	}
368 
369 	while (!req.complete)
370 		cuda_poll();
371 }
372 #endif /* CONFIG_ADB_CUDA */
373 
374 /*
375  *-------------------------------------------------------------------
376  * Below this point are the generic routines; they'll dispatch to the
377  * correct routine for the hardware on which we're running.
378  *-------------------------------------------------------------------
379  */
380 
381 void mac_pram_read(int offset, __u8 *buffer, int len)
382 {
383 	__u8 (*func)(int);
384 	int i;
385 
386 	switch (macintosh_config->adb_type) {
387 	case MAC_ADB_IOP:
388 	case MAC_ADB_II:
389 	case MAC_ADB_PB1:
390 		func = via_read_pram;
391 		break;
392 #ifdef CONFIG_ADB_CUDA
393 	case MAC_ADB_EGRET:
394 	case MAC_ADB_CUDA:
395 		func = cuda_read_pram;
396 		break;
397 #endif
398 #ifdef CONFIG_ADB_PMU
399 	case MAC_ADB_PB2:
400 		func = pmu_read_pram;
401 		break;
402 #endif
403 	default:
404 		return;
405 	}
406 	for (i = 0 ; i < len ; i++) {
407 		buffer[i] = (*func)(offset++);
408 	}
409 }
410 
411 void mac_pram_write(int offset, __u8 *buffer, int len)
412 {
413 	void (*func)(int, __u8);
414 	int i;
415 
416 	switch (macintosh_config->adb_type) {
417 	case MAC_ADB_IOP:
418 	case MAC_ADB_II:
419 	case MAC_ADB_PB1:
420 		func = via_write_pram;
421 		break;
422 #ifdef CONFIG_ADB_CUDA
423 	case MAC_ADB_EGRET:
424 	case MAC_ADB_CUDA:
425 		func = cuda_write_pram;
426 		break;
427 #endif
428 #ifdef CONFIG_ADB_PMU
429 	case MAC_ADB_PB2:
430 		func = pmu_write_pram;
431 		break;
432 #endif
433 	default:
434 		return;
435 	}
436 	for (i = 0 ; i < len ; i++) {
437 		(*func)(offset++, buffer[i]);
438 	}
439 }
440 
441 void mac_poweroff(void)
442 {
443 	if (oss_present) {
444 		oss_shutdown();
445 	} else if (macintosh_config->adb_type == MAC_ADB_II) {
446 		via_shutdown();
447 #ifdef CONFIG_ADB_CUDA
448 	} else if (macintosh_config->adb_type == MAC_ADB_EGRET ||
449 	           macintosh_config->adb_type == MAC_ADB_CUDA) {
450 		cuda_shutdown();
451 #endif
452 #ifdef CONFIG_ADB_PMU
453 	} else if (macintosh_config->adb_type == MAC_ADB_PB2) {
454 		pmu_shutdown();
455 #endif
456 	}
457 
458 	pr_crit("It is now safe to turn off your Macintosh.\n");
459 	local_irq_disable();
460 	while(1);
461 }
462 
463 void mac_reset(void)
464 {
465 	if (macintosh_config->adb_type == MAC_ADB_II) {
466 		unsigned long flags;
467 
468 		/* need ROMBASE in booter */
469 		/* indeed, plus need to MAP THE ROM !! */
470 
471 		if (mac_bi_data.rombase == 0)
472 			mac_bi_data.rombase = 0x40800000;
473 
474 		/* works on some */
475 		rom_reset = (void *) (mac_bi_data.rombase + 0xa);
476 
477 		if (macintosh_config->ident == MAC_MODEL_SE30) {
478 			/*
479 			 * MSch: Machines known to crash on ROM reset ...
480 			 */
481 		} else {
482 			local_irq_save(flags);
483 
484 			rom_reset();
485 
486 			local_irq_restore(flags);
487 		}
488 #ifdef CONFIG_ADB_CUDA
489 	} else if (macintosh_config->adb_type == MAC_ADB_EGRET ||
490 	           macintosh_config->adb_type == MAC_ADB_CUDA) {
491 		cuda_restart();
492 #endif
493 #ifdef CONFIG_ADB_PMU
494 	} else if (macintosh_config->adb_type == MAC_ADB_PB2) {
495 		pmu_restart();
496 #endif
497 	} else if (CPU_IS_030) {
498 
499 		/* 030-specific reset routine.  The idea is general, but the
500 		 * specific registers to reset are '030-specific.  Until I
501 		 * have a non-030 machine, I can't test anything else.
502 		 *  -- C. Scott Ananian <cananian@alumni.princeton.edu>
503 		 */
504 
505 		unsigned long rombase = 0x40000000;
506 
507 		/* make a 1-to-1 mapping, using the transparent tran. reg. */
508 		unsigned long virt = (unsigned long) mac_reset;
509 		unsigned long phys = virt_to_phys(mac_reset);
510 		unsigned long addr = (phys&0xFF000000)|0x8777;
511 		unsigned long offset = phys-virt;
512 
513 		local_irq_disable(); /* lets not screw this up, ok? */
514 		__asm__ __volatile__(".chip 68030\n\t"
515 				     "pmove %0,%/tt0\n\t"
516 				     ".chip 68k"
517 				     : : "m" (addr));
518 		/* Now jump to physical address so we can disable MMU */
519 		__asm__ __volatile__(
520 		    ".chip 68030\n\t"
521 		    "lea %/pc@(1f),%/a0\n\t"
522 		    "addl %0,%/a0\n\t"/* fixup target address and stack ptr */
523 		    "addl %0,%/sp\n\t"
524 		    "pflusha\n\t"
525 		    "jmp %/a0@\n\t" /* jump into physical memory */
526 		    "0:.long 0\n\t" /* a constant zero. */
527 		    /* OK.  Now reset everything and jump to reset vector. */
528 		    "1:\n\t"
529 		    "lea %/pc@(0b),%/a0\n\t"
530 		    "pmove %/a0@, %/tc\n\t" /* disable mmu */
531 		    "pmove %/a0@, %/tt0\n\t" /* disable tt0 */
532 		    "pmove %/a0@, %/tt1\n\t" /* disable tt1 */
533 		    "movel #0, %/a0\n\t"
534 		    "movec %/a0, %/vbr\n\t" /* clear vector base register */
535 		    "movec %/a0, %/cacr\n\t" /* disable caches */
536 		    "movel #0x0808,%/a0\n\t"
537 		    "movec %/a0, %/cacr\n\t" /* flush i&d caches */
538 		    "movew #0x2700,%/sr\n\t" /* set up status register */
539 		    "movel %1@(0x0),%/a0\n\t"/* load interrupt stack pointer */
540 		    "movec %/a0, %/isp\n\t"
541 		    "movel %1@(0x4),%/a0\n\t" /* load reset vector */
542 		    "reset\n\t" /* reset external devices */
543 		    "jmp %/a0@\n\t" /* jump to the reset vector */
544 		    ".chip 68k"
545 		    : : "r" (offset), "a" (rombase) : "a0");
546 	}
547 
548 	/* should never get here */
549 	pr_crit("Restart failed. Please restart manually.\n");
550 	local_irq_disable();
551 	while(1);
552 }
553 
554 /*
555  * This function translates seconds since 1970 into a proper date.
556  *
557  * Algorithm cribbed from glibc2.1, __offtime().
558  *
559  * This is roughly same as rtc_time64_to_tm(), which we should probably
560  * use here, but it's only available when CONFIG_RTC_LIB is enabled.
561  */
562 #define SECS_PER_MINUTE (60)
563 #define SECS_PER_HOUR  (SECS_PER_MINUTE * 60)
564 #define SECS_PER_DAY   (SECS_PER_HOUR * 24)
565 
566 static void unmktime(time64_t time, long offset,
567 		     int *yearp, int *monp, int *dayp,
568 		     int *hourp, int *minp, int *secp)
569 {
570         /* How many days come before each month (0-12).  */
571 	static const unsigned short int __mon_yday[2][13] =
572 	{
573 		/* Normal years.  */
574 		{ 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
575 		/* Leap years.  */
576 		{ 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
577 	};
578 	int days, rem, y, wday, yday;
579 	const unsigned short int *ip;
580 
581 	days = div_u64_rem(time, SECS_PER_DAY, &rem);
582 	rem += offset;
583 	while (rem < 0) {
584 		rem += SECS_PER_DAY;
585 		--days;
586 	}
587 	while (rem >= SECS_PER_DAY) {
588 		rem -= SECS_PER_DAY;
589 		++days;
590 	}
591 	*hourp = rem / SECS_PER_HOUR;
592 	rem %= SECS_PER_HOUR;
593 	*minp = rem / SECS_PER_MINUTE;
594 	*secp = rem % SECS_PER_MINUTE;
595 	/* January 1, 1970 was a Thursday. */
596 	wday = (4 + days) % 7; /* Day in the week. Not currently used */
597 	if (wday < 0) wday += 7;
598 	y = 1970;
599 
600 #define DIV(a, b) ((a) / (b) - ((a) % (b) < 0))
601 #define LEAPS_THRU_END_OF(y) (DIV (y, 4) - DIV (y, 100) + DIV (y, 400))
602 #define __isleap(year)	\
603   ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
604 
605 	while (days < 0 || days >= (__isleap (y) ? 366 : 365))
606 	{
607 		/* Guess a corrected year, assuming 365 days per year.  */
608 		long int yg = y + days / 365 - (days % 365 < 0);
609 
610 		/* Adjust DAYS and Y to match the guessed year.  */
611 		days -= (yg - y) * 365 +
612 			LEAPS_THRU_END_OF(yg - 1) - LEAPS_THRU_END_OF(y - 1);
613 		y = yg;
614 	}
615 	*yearp = y - 1900;
616 	yday = days; /* day in the year.  Not currently used. */
617 	ip = __mon_yday[__isleap(y)];
618 	for (y = 11; days < (long int) ip[y]; --y)
619 		continue;
620 	days -= ip[y];
621 	*monp = y;
622 	*dayp = days + 1; /* day in the month */
623 	return;
624 }
625 
626 /*
627  * Read/write the hardware clock.
628  */
629 
630 int mac_hwclk(int op, struct rtc_time *t)
631 {
632 	time64_t now;
633 
634 	if (!op) { /* read */
635 		switch (macintosh_config->adb_type) {
636 		case MAC_ADB_IOP:
637 		case MAC_ADB_II:
638 		case MAC_ADB_PB1:
639 			now = via_read_time();
640 			break;
641 #ifdef CONFIG_ADB_CUDA
642 		case MAC_ADB_EGRET:
643 		case MAC_ADB_CUDA:
644 			now = cuda_read_time();
645 			break;
646 #endif
647 #ifdef CONFIG_ADB_PMU
648 		case MAC_ADB_PB2:
649 			now = pmu_read_time();
650 			break;
651 #endif
652 		default:
653 			now = 0;
654 		}
655 
656 		t->tm_wday = 0;
657 		unmktime(now, 0,
658 			 &t->tm_year, &t->tm_mon, &t->tm_mday,
659 			 &t->tm_hour, &t->tm_min, &t->tm_sec);
660 		pr_debug("%s: read %04d-%02d-%-2d %02d:%02d:%02d\n",
661 		         __func__, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
662 		         t->tm_hour, t->tm_min, t->tm_sec);
663 	} else { /* write */
664 		pr_debug("%s: tried to write %04d-%02d-%-2d %02d:%02d:%02d\n",
665 		         __func__, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
666 		         t->tm_hour, t->tm_min, t->tm_sec);
667 
668 		now = mktime64(t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
669 			       t->tm_hour, t->tm_min, t->tm_sec);
670 
671 		switch (macintosh_config->adb_type) {
672 		case MAC_ADB_IOP:
673 		case MAC_ADB_II:
674 		case MAC_ADB_PB1:
675 			via_write_time(now);
676 			break;
677 #ifdef CONFIG_ADB_CUDA
678 		case MAC_ADB_EGRET:
679 		case MAC_ADB_CUDA:
680 			cuda_write_time(now);
681 			break;
682 #endif
683 #ifdef CONFIG_ADB_PMU
684 		case MAC_ADB_PB2:
685 			pmu_write_time(now);
686 			break;
687 #endif
688 		default:
689 			return -ENODEV;
690 		}
691 	}
692 	return 0;
693 }
694