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
38static void (*rom_reset)(void);
39
40#if IS_ENABLED(CONFIG_NVRAM)
41#ifdef CONFIG_ADB_CUDA
42static 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
54static 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
67static 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
79static 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
98static __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
125static 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
175static 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(data: (command & 0xFF00) >> 8);
192 via_rtc_send(data: command & 0xFF);
193 is_read = command & (RTC_FLG_READ << 8);
194 } else { /* one-byte command */
195 via_rtc_send(data: 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: *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)
212static 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), data: &temp);
217
218 return temp;
219}
220
221static 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), data: &temp);
227
228 temp = data;
229 via_rtc_command(RTC_CMD_XPRAM_WRITE | RTC_CMD_XPRAM_ARG(offset), data: &temp);
230
231 temp = 0x55 | RTC_FLG_WRITE_PROTECT;
232 via_rtc_command(RTC_CMD_WRITE(RTC_REG_WRITE_PROTECT), data: &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
243static 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), data: &last_result.cdata[3]);
252 via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_1), data: &last_result.cdata[2]);
253 via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_2), data: &last_result.cdata[1]);
254 via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_3), data: &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 data: &result.cdata[3]);
264 via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_1),
265 data: &result.cdata[2]);
266 via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_2),
267 data: &result.cdata[1]);
268 via_rtc_command(RTC_CMD_READ(RTC_REG_SECONDS_3),
269 data: &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
293static 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(year: tm->tm_year + 1900, mon: tm->tm_mon + 1, day: tm->tm_mday,
303 hour: tm->tm_hour, min: tm->tm_min, sec: 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), data: &temp);
309
310 data.idata = lower_32_bits(time + RTC_OFFSET);
311 via_rtc_command(RTC_CMD_WRITE(RTC_REG_SECONDS_0), data: &data.cdata[3]);
312 via_rtc_command(RTC_CMD_WRITE(RTC_REG_SECONDS_1), data: &data.cdata[2]);
313 via_rtc_command(RTC_CMD_WRITE(RTC_REG_SECONDS_2), data: &data.cdata[1]);
314 via_rtc_command(RTC_CMD_WRITE(RTC_REG_SECONDS_3), data: &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), data: &temp);
320}
321
322static 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
335static void oss_shutdown(void)
336{
337 oss->rom_ctrl = OSS_POWEROFF;
338}
339
340#ifdef CONFIG_ADB_CUDA
341static 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
351static 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)
381unsigned 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(offset: 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
402void 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(data: val, offset: 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
426ssize_t mac_pram_get_size(void)
427{
428 return 256;
429}
430#endif /* CONFIG_NVRAM */
431
432void 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
454void mac_reset(void)
455{
456 if (macintosh_config->adb_type == MAC_ADB_II &&
457 macintosh_config->ident != MAC_MODEL_SE30) {
458 /* need ROMBASE in booter */
459 /* indeed, plus need to MAP THE ROM !! */
460
461 if (mac_bi_data.rombase == 0)
462 mac_bi_data.rombase = 0x40800000;
463
464 /* works on some */
465 rom_reset = (void *) (mac_bi_data.rombase + 0xa);
466
467 local_irq_disable();
468 rom_reset();
469#ifdef CONFIG_ADB_CUDA
470 } else if (macintosh_config->adb_type == MAC_ADB_EGRET ||
471 macintosh_config->adb_type == MAC_ADB_CUDA) {
472 cuda_restart();
473#endif
474#ifdef CONFIG_ADB_PMU
475 } else if (macintosh_config->adb_type == MAC_ADB_PB2) {
476 pmu_restart();
477#endif
478 } else if (CPU_IS_030) {
479
480 /* 030-specific reset routine. The idea is general, but the
481 * specific registers to reset are '030-specific. Until I
482 * have a non-030 machine, I can't test anything else.
483 * -- C. Scott Ananian <cananian@alumni.princeton.edu>
484 */
485
486 unsigned long rombase = 0x40000000;
487
488 /* make a 1-to-1 mapping, using the transparent tran. reg. */
489 unsigned long virt = (unsigned long) mac_reset;
490 unsigned long phys = virt_to_phys(address: mac_reset);
491 unsigned long addr = (phys&0xFF000000)|0x8777;
492 unsigned long offset = phys-virt;
493
494 local_irq_disable(); /* lets not screw this up, ok? */
495 __asm__ __volatile__(".chip 68030\n\t"
496 "pmove %0,%/tt0\n\t"
497 ".chip 68k"
498 : : "m" (addr));
499 /* Now jump to physical address so we can disable MMU */
500 __asm__ __volatile__(
501 ".chip 68030\n\t"
502 "lea %/pc@(1f),%/a0\n\t"
503 "addl %0,%/a0\n\t"/* fixup target address and stack ptr */
504 "addl %0,%/sp\n\t"
505 "pflusha\n\t"
506 "jmp %/a0@\n\t" /* jump into physical memory */
507 "0:.long 0\n\t" /* a constant zero. */
508 /* OK. Now reset everything and jump to reset vector. */
509 "1:\n\t"
510 "lea %/pc@(0b),%/a0\n\t"
511 "pmove %/a0@, %/tc\n\t" /* disable mmu */
512 "pmove %/a0@, %/tt0\n\t" /* disable tt0 */
513 "pmove %/a0@, %/tt1\n\t" /* disable tt1 */
514 "movel #0, %/a0\n\t"
515 "movec %/a0, %/vbr\n\t" /* clear vector base register */
516 "movec %/a0, %/cacr\n\t" /* disable caches */
517 "movel #0x0808,%/a0\n\t"
518 "movec %/a0, %/cacr\n\t" /* flush i&d caches */
519 "movew #0x2700,%/sr\n\t" /* set up status register */
520 "movel %1@(0x0),%/a0\n\t"/* load interrupt stack pointer */
521 "movec %/a0, %/isp\n\t"
522 "movel %1@(0x4),%/a0\n\t" /* load reset vector */
523 "reset\n\t" /* reset external devices */
524 "jmp %/a0@\n\t" /* jump to the reset vector */
525 ".chip 68k"
526 : : "r" (offset), "a" (rombase) : "a0");
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
547static 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(dividend: time, SECS_PER_DAY, remainder: &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
610int 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(time: now, offset: 0,
638 yearp: &t->tm_year, monp: &t->tm_mon, dayp: &t->tm_mday,
639 hourp: &t->tm_hour, minp: &t->tm_min, secp: &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(tm: 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

source code of linux/arch/m68k/mac/misc.c