xref: /openbmc/linux/arch/m68k/bvme6000/config.c (revision 64c70b1c)
1 /*
2  *  arch/m68k/bvme6000/config.c
3  *
4  *  Copyright (C) 1997 Richard Hirst [richard@sleepie.demon.co.uk]
5  *
6  * Based on:
7  *
8  *  linux/amiga/config.c
9  *
10  *  Copyright (C) 1993 Hamish Macdonald
11  *
12  * This file is subject to the terms and conditions of the GNU General Public
13  * License.  See the file README.legal in the main directory of this archive
14  * for more details.
15  */
16 
17 #include <linux/types.h>
18 #include <linux/kernel.h>
19 #include <linux/mm.h>
20 #include <linux/tty.h>
21 #include <linux/console.h>
22 #include <linux/linkage.h>
23 #include <linux/init.h>
24 #include <linux/major.h>
25 #include <linux/genhd.h>
26 #include <linux/rtc.h>
27 #include <linux/interrupt.h>
28 
29 #include <asm/bootinfo.h>
30 #include <asm/system.h>
31 #include <asm/pgtable.h>
32 #include <asm/setup.h>
33 #include <asm/irq.h>
34 #include <asm/traps.h>
35 #include <asm/rtc.h>
36 #include <asm/machdep.h>
37 #include <asm/bvme6000hw.h>
38 
39 static void bvme6000_get_model(char *model);
40 static int  bvme6000_get_hardware_list(char *buffer);
41 extern void bvme6000_sched_init(irq_handler_t handler);
42 extern unsigned long bvme6000_gettimeoffset (void);
43 extern int bvme6000_hwclk (int, struct rtc_time *);
44 extern int bvme6000_set_clock_mmss (unsigned long);
45 extern void bvme6000_reset (void);
46 extern void bvme6000_waitbut(void);
47 void bvme6000_set_vectors (void);
48 
49 static unsigned char bcd2bin (unsigned char b);
50 static unsigned char bin2bcd (unsigned char b);
51 
52 /* Save tick handler routine pointer, will point to do_timer() in
53  * kernel/sched.c, called via bvme6000_process_int() */
54 
55 static irq_handler_t tick_handler;
56 
57 
58 int bvme6000_parse_bootinfo(const struct bi_record *bi)
59 {
60 	if (bi->tag == BI_VME_TYPE)
61 		return 0;
62 	else
63 		return 1;
64 }
65 
66 void bvme6000_reset(void)
67 {
68 	volatile PitRegsPtr pit = (PitRegsPtr)BVME_PIT_BASE;
69 
70 	printk ("\r\n\nCalled bvme6000_reset\r\n"
71 			"\r\r\r\r\r\r\r\r\r\r\r\r\r\r\r\r\r\r");
72 	/* The string of returns is to delay the reset until the whole
73 	 * message is output. */
74 	/* Enable the watchdog, via PIT port C bit 4 */
75 
76 	pit->pcddr	|= 0x10;	/* WDOG enable */
77 
78 	while(1)
79 		;
80 }
81 
82 static void bvme6000_get_model(char *model)
83 {
84     sprintf(model, "BVME%d000", m68k_cputype == CPU_68060 ? 6 : 4);
85 }
86 
87 
88 /* No hardware options on BVME6000? */
89 
90 static int bvme6000_get_hardware_list(char *buffer)
91 {
92     *buffer = '\0';
93     return 0;
94 }
95 
96 /*
97  * This function is called during kernel startup to initialize
98  * the bvme6000 IRQ handling routines.
99  */
100 static void bvme6000_init_IRQ(void)
101 {
102 	m68k_setup_user_interrupt(VEC_USER, 192, NULL);
103 }
104 
105 void __init config_bvme6000(void)
106 {
107     volatile PitRegsPtr pit = (PitRegsPtr)BVME_PIT_BASE;
108 
109     /* Board type is only set by newer versions of vmelilo/tftplilo */
110     if (!vme_brdtype) {
111 	if (m68k_cputype == CPU_68060)
112 	    vme_brdtype = VME_TYPE_BVME6000;
113 	else
114 	    vme_brdtype = VME_TYPE_BVME4000;
115     }
116 #if 0
117     /* Call bvme6000_set_vectors() so ABORT will work, along with BVMBug
118      * debugger.  Note trap_init() will splat the abort vector, but
119      * bvme6000_init_IRQ() will put it back again.  Hopefully. */
120 
121     bvme6000_set_vectors();
122 #endif
123 
124     mach_max_dma_address = 0xffffffff;
125     mach_sched_init      = bvme6000_sched_init;
126     mach_init_IRQ        = bvme6000_init_IRQ;
127     mach_gettimeoffset   = bvme6000_gettimeoffset;
128     mach_hwclk           = bvme6000_hwclk;
129     mach_set_clock_mmss	 = bvme6000_set_clock_mmss;
130     mach_reset		 = bvme6000_reset;
131     mach_get_model       = bvme6000_get_model;
132     mach_get_hardware_list = bvme6000_get_hardware_list;
133 
134     printk ("Board is %sconfigured as a System Controller\n",
135 		*config_reg_ptr & BVME_CONFIG_SW1 ? "" : "not ");
136 
137     /* Now do the PIT configuration */
138 
139     pit->pgcr	= 0x00;	/* Unidirectional 8 bit, no handshake for now */
140     pit->psrr	= 0x18;	/* PIACK and PIRQ functions enabled */
141     pit->pacr	= 0x00;	/* Sub Mode 00, H2 i/p, no DMA */
142     pit->padr	= 0x00;	/* Just to be tidy! */
143     pit->paddr	= 0x00;	/* All inputs for now (safest) */
144     pit->pbcr	= 0x80;	/* Sub Mode 1x, H4 i/p, no DMA */
145     pit->pbdr	= 0xbc | (*config_reg_ptr & BVME_CONFIG_SW1 ? 0 : 0x40);
146 			/* PRI, SYSCON?, Level3, SCC clks from xtal */
147     pit->pbddr	= 0xf3;	/* Mostly outputs */
148     pit->pcdr	= 0x01;	/* PA transceiver disabled */
149     pit->pcddr	= 0x03;	/* WDOG disable */
150 
151     /* Disable snooping for Ethernet and VME accesses */
152 
153     bvme_acr_addrctl = 0;
154 }
155 
156 
157 irqreturn_t bvme6000_abort_int (int irq, void *dev_id)
158 {
159         unsigned long *new = (unsigned long *)vectors;
160         unsigned long *old = (unsigned long *)0xf8000000;
161 
162         /* Wait for button release */
163         while (*(volatile unsigned char *)BVME_LOCAL_IRQ_STAT & BVME_ABORT_STATUS)
164                 ;
165 
166         *(new+4) = *(old+4);            /* Illegal instruction */
167         *(new+9) = *(old+9);            /* Trace */
168         *(new+47) = *(old+47);          /* Trap #15 */
169         *(new+0x1f) = *(old+0x1f);      /* ABORT switch */
170 	return IRQ_HANDLED;
171 }
172 
173 
174 static irqreturn_t bvme6000_timer_int (int irq, void *dev_id)
175 {
176     volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
177     unsigned char msr = rtc->msr & 0xc0;
178 
179     rtc->msr = msr | 0x20;		/* Ack the interrupt */
180 
181     return tick_handler(irq, dev_id);
182 }
183 
184 /*
185  * Set up the RTC timer 1 to mode 2, so T1 output toggles every 5ms
186  * (40000 x 125ns).  It will interrupt every 10ms, when T1 goes low.
187  * So, when reading the elapsed time, you should read timer1,
188  * subtract it from 39999, and then add 40000 if T1 is high.
189  * That gives you the number of 125ns ticks in to the 10ms period,
190  * so divide by 8 to get the microsecond result.
191  */
192 
193 void bvme6000_sched_init (irq_handler_t timer_routine)
194 {
195     volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
196     unsigned char msr = rtc->msr & 0xc0;
197 
198     rtc->msr = 0;	/* Ensure timer registers accessible */
199 
200     tick_handler = timer_routine;
201     if (request_irq(BVME_IRQ_RTC, bvme6000_timer_int, 0,
202 				"timer", bvme6000_timer_int))
203 	panic ("Couldn't register timer int");
204 
205     rtc->t1cr_omr = 0x04;	/* Mode 2, ext clk */
206     rtc->t1msb = 39999 >> 8;
207     rtc->t1lsb = 39999 & 0xff;
208     rtc->irr_icr1 &= 0xef;	/* Route timer 1 to INTR pin */
209     rtc->msr = 0x40;		/* Access int.cntrl, etc */
210     rtc->pfr_icr0 = 0x80;	/* Just timer 1 ints enabled */
211     rtc->irr_icr1 = 0;
212     rtc->t1cr_omr = 0x0a;	/* INTR+T1 active lo, push-pull */
213     rtc->t0cr_rtmr &= 0xdf;	/* Stop timers in standby */
214     rtc->msr = 0;		/* Access timer 1 control */
215     rtc->t1cr_omr = 0x05;	/* Mode 2, ext clk, GO */
216 
217     rtc->msr = msr;
218 
219     if (request_irq(BVME_IRQ_ABORT, bvme6000_abort_int, 0,
220 				"abort", bvme6000_abort_int))
221 	panic ("Couldn't register abort int");
222 }
223 
224 
225 /* This is always executed with interrupts disabled.  */
226 
227 /*
228  * NOTE:  Don't accept any readings within 5us of rollover, as
229  * the T1INT bit may be a little slow getting set.  There is also
230  * a fault in the chip, meaning that reads may produce invalid
231  * results...
232  */
233 
234 unsigned long bvme6000_gettimeoffset (void)
235 {
236     volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
237     volatile PitRegsPtr pit = (PitRegsPtr)BVME_PIT_BASE;
238     unsigned char msr = rtc->msr & 0xc0;
239     unsigned char t1int, t1op;
240     unsigned long v = 800000, ov;
241 
242     rtc->msr = 0;	/* Ensure timer registers accessible */
243 
244     do {
245 	ov = v;
246 	t1int = rtc->msr & 0x20;
247 	t1op  = pit->pcdr & 0x04;
248 	rtc->t1cr_omr |= 0x40;		/* Latch timer1 */
249 	v = rtc->t1msb << 8;		/* Read timer1 */
250 	v |= rtc->t1lsb;		/* Read timer1 */
251     } while (t1int != (rtc->msr & 0x20) ||
252 		t1op != (pit->pcdr & 0x04) ||
253 			abs(ov-v) > 80 ||
254 				v > 39960);
255 
256     v = 39999 - v;
257     if (!t1op)				/* If in second half cycle.. */
258 	v += 40000;
259     v /= 8;				/* Convert ticks to microseconds */
260     if (t1int)
261 	v += 10000;			/* Int pending, + 10ms */
262     rtc->msr = msr;
263 
264     return v;
265 }
266 
267 static unsigned char bcd2bin (unsigned char b)
268 {
269 	return ((b>>4)*10 + (b&15));
270 }
271 
272 static unsigned char bin2bcd (unsigned char b)
273 {
274 	return (((b/10)*16) + (b%10));
275 }
276 
277 
278 /*
279  * Looks like op is non-zero for setting the clock, and zero for
280  * reading the clock.
281  *
282  *  struct hwclk_time {
283  *         unsigned        sec;       0..59
284  *         unsigned        min;       0..59
285  *         unsigned        hour;      0..23
286  *         unsigned        day;       1..31
287  *         unsigned        mon;       0..11
288  *         unsigned        year;      00...
289  *         int             wday;      0..6, 0 is Sunday, -1 means unknown/don't set
290  * };
291  */
292 
293 int bvme6000_hwclk(int op, struct rtc_time *t)
294 {
295 	volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
296 	unsigned char msr = rtc->msr & 0xc0;
297 
298 	rtc->msr = 0x40;	/* Ensure clock and real-time-mode-register
299 				 * are accessible */
300 	if (op)
301 	{	/* Write.... */
302 		rtc->t0cr_rtmr = t->tm_year%4;
303 		rtc->bcd_tenms = 0;
304 		rtc->bcd_sec = bin2bcd(t->tm_sec);
305 		rtc->bcd_min = bin2bcd(t->tm_min);
306 		rtc->bcd_hr  = bin2bcd(t->tm_hour);
307 		rtc->bcd_dom = bin2bcd(t->tm_mday);
308 		rtc->bcd_mth = bin2bcd(t->tm_mon + 1);
309 		rtc->bcd_year = bin2bcd(t->tm_year%100);
310 		if (t->tm_wday >= 0)
311 			rtc->bcd_dow = bin2bcd(t->tm_wday+1);
312 		rtc->t0cr_rtmr = t->tm_year%4 | 0x08;
313 	}
314 	else
315 	{	/* Read....  */
316 		do {
317 			t->tm_sec  = bcd2bin(rtc->bcd_sec);
318 			t->tm_min  = bcd2bin(rtc->bcd_min);
319 			t->tm_hour = bcd2bin(rtc->bcd_hr);
320 			t->tm_mday = bcd2bin(rtc->bcd_dom);
321 			t->tm_mon  = bcd2bin(rtc->bcd_mth)-1;
322 			t->tm_year = bcd2bin(rtc->bcd_year);
323 			if (t->tm_year < 70)
324 				t->tm_year += 100;
325 			t->tm_wday = bcd2bin(rtc->bcd_dow)-1;
326 		} while (t->tm_sec != bcd2bin(rtc->bcd_sec));
327 	}
328 
329 	rtc->msr = msr;
330 
331 	return 0;
332 }
333 
334 /*
335  * Set the minutes and seconds from seconds value 'nowtime'.  Fail if
336  * clock is out by > 30 minutes.  Logic lifted from atari code.
337  * Algorithm is to wait for the 10ms register to change, and then to
338  * wait a short while, and then set it.
339  */
340 
341 int bvme6000_set_clock_mmss (unsigned long nowtime)
342 {
343 	int retval = 0;
344 	short real_seconds = nowtime % 60, real_minutes = (nowtime / 60) % 60;
345 	unsigned char rtc_minutes, rtc_tenms;
346 	volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
347 	unsigned char msr = rtc->msr & 0xc0;
348 	unsigned long flags;
349 	volatile int i;
350 
351 	rtc->msr = 0;		/* Ensure clock accessible */
352 	rtc_minutes = bcd2bin (rtc->bcd_min);
353 
354 	if ((rtc_minutes < real_minutes
355 		? real_minutes - rtc_minutes
356 			: rtc_minutes - real_minutes) < 30)
357 	{
358 		local_irq_save(flags);
359 		rtc_tenms = rtc->bcd_tenms;
360 		while (rtc_tenms == rtc->bcd_tenms)
361 			;
362 		for (i = 0; i < 1000; i++)
363 			;
364 		rtc->bcd_min = bin2bcd(real_minutes);
365 		rtc->bcd_sec = bin2bcd(real_seconds);
366 		local_irq_restore(flags);
367 	}
368 	else
369 		retval = -1;
370 
371 	rtc->msr = msr;
372 
373 	return retval;
374 }
375 
376