xref: /openbmc/linux/arch/m68k/bvme6000/config.c (revision 1da177e4)
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 extern irqreturn_t bvme6000_process_int (int level, struct pt_regs *regs);
40 extern void bvme6000_init_IRQ (void);
41 extern void bvme6000_free_irq (unsigned int, void *);
42 extern int  show_bvme6000_interrupts(struct seq_file *, void *);
43 extern void bvme6000_enable_irq (unsigned int);
44 extern void bvme6000_disable_irq (unsigned int);
45 static void bvme6000_get_model(char *model);
46 static int  bvme6000_get_hardware_list(char *buffer);
47 extern int  bvme6000_request_irq(unsigned int irq, irqreturn_t (*handler)(int, void *, struct pt_regs *), unsigned long flags, const char *devname, void *dev_id);
48 extern void bvme6000_sched_init(irqreturn_t (*handler)(int, void *, struct pt_regs *));
49 extern unsigned long bvme6000_gettimeoffset (void);
50 extern int bvme6000_hwclk (int, struct rtc_time *);
51 extern int bvme6000_set_clock_mmss (unsigned long);
52 extern void bvme6000_reset (void);
53 extern void bvme6000_waitbut(void);
54 void bvme6000_set_vectors (void);
55 
56 static unsigned char bcd2bin (unsigned char b);
57 static unsigned char bin2bcd (unsigned char b);
58 
59 /* Save tick handler routine pointer, will point to do_timer() in
60  * kernel/sched.c, called via bvme6000_process_int() */
61 
62 static irqreturn_t (*tick_handler)(int, void *, struct pt_regs *);
63 
64 
65 int bvme6000_parse_bootinfo(const struct bi_record *bi)
66 {
67 	if (bi->tag == BI_VME_TYPE)
68 		return 0;
69 	else
70 		return 1;
71 }
72 
73 void bvme6000_reset(void)
74 {
75 	volatile PitRegsPtr pit = (PitRegsPtr)BVME_PIT_BASE;
76 
77 	printk ("\r\n\nCalled bvme6000_reset\r\n"
78 			"\r\r\r\r\r\r\r\r\r\r\r\r\r\r\r\r\r\r");
79 	/* The string of returns is to delay the reset until the whole
80 	 * message is output. */
81 	/* Enable the watchdog, via PIT port C bit 4 */
82 
83 	pit->pcddr	|= 0x10;	/* WDOG enable */
84 
85 	while(1)
86 		;
87 }
88 
89 static void bvme6000_get_model(char *model)
90 {
91     sprintf(model, "BVME%d000", m68k_cputype == CPU_68060 ? 6 : 4);
92 }
93 
94 
95 /* No hardware options on BVME6000? */
96 
97 static int bvme6000_get_hardware_list(char *buffer)
98 {
99     *buffer = '\0';
100     return 0;
101 }
102 
103 
104 void __init config_bvme6000(void)
105 {
106     volatile PitRegsPtr pit = (PitRegsPtr)BVME_PIT_BASE;
107 
108     /* Board type is only set by newer versions of vmelilo/tftplilo */
109     if (!vme_brdtype) {
110 	if (m68k_cputype == CPU_68060)
111 	    vme_brdtype = VME_TYPE_BVME6000;
112 	else
113 	    vme_brdtype = VME_TYPE_BVME4000;
114     }
115 #if 0
116     /* Call bvme6000_set_vectors() so ABORT will work, along with BVMBug
117      * debugger.  Note trap_init() will splat the abort vector, but
118      * bvme6000_init_IRQ() will put it back again.  Hopefully. */
119 
120     bvme6000_set_vectors();
121 #endif
122 
123     mach_max_dma_address = 0xffffffff;
124     mach_sched_init      = bvme6000_sched_init;
125     mach_init_IRQ        = bvme6000_init_IRQ;
126     mach_gettimeoffset   = bvme6000_gettimeoffset;
127     mach_hwclk           = bvme6000_hwclk;
128     mach_set_clock_mmss	 = bvme6000_set_clock_mmss;
129     mach_reset		 = bvme6000_reset;
130     mach_free_irq	 = bvme6000_free_irq;
131     mach_process_int	 = bvme6000_process_int;
132     mach_get_irq_list	 = show_bvme6000_interrupts;
133     mach_request_irq	 = bvme6000_request_irq;
134     enable_irq		 = bvme6000_enable_irq;
135     disable_irq          = bvme6000_disable_irq;
136     mach_get_model       = bvme6000_get_model;
137     mach_get_hardware_list = bvme6000_get_hardware_list;
138 
139     printk ("Board is %sconfigured as a System Controller\n",
140 		*config_reg_ptr & BVME_CONFIG_SW1 ? "" : "not ");
141 
142     /* Now do the PIT configuration */
143 
144     pit->pgcr	= 0x00;	/* Unidirectional 8 bit, no handshake for now */
145     pit->psrr	= 0x18;	/* PIACK and PIRQ fucntions enabled */
146     pit->pacr	= 0x00;	/* Sub Mode 00, H2 i/p, no DMA */
147     pit->padr	= 0x00;	/* Just to be tidy! */
148     pit->paddr	= 0x00;	/* All inputs for now (safest) */
149     pit->pbcr	= 0x80;	/* Sub Mode 1x, H4 i/p, no DMA */
150     pit->pbdr	= 0xbc | (*config_reg_ptr & BVME_CONFIG_SW1 ? 0 : 0x40);
151 			/* PRI, SYSCON?, Level3, SCC clks from xtal */
152     pit->pbddr	= 0xf3;	/* Mostly outputs */
153     pit->pcdr	= 0x01;	/* PA transceiver disabled */
154     pit->pcddr	= 0x03;	/* WDOG disable */
155 
156     /* Disable snooping for Ethernet and VME accesses */
157 
158     bvme_acr_addrctl = 0;
159 }
160 
161 
162 irqreturn_t bvme6000_abort_int (int irq, void *dev_id, struct pt_regs *fp)
163 {
164         unsigned long *new = (unsigned long *)vectors;
165         unsigned long *old = (unsigned long *)0xf8000000;
166 
167         /* Wait for button release */
168         while (*(volatile unsigned char *)BVME_LOCAL_IRQ_STAT & BVME_ABORT_STATUS)
169                 ;
170 
171         *(new+4) = *(old+4);            /* Illegal instruction */
172         *(new+9) = *(old+9);            /* Trace */
173         *(new+47) = *(old+47);          /* Trap #15 */
174         *(new+0x1f) = *(old+0x1f);      /* ABORT switch */
175 	return IRQ_HANDLED;
176 }
177 
178 
179 static irqreturn_t bvme6000_timer_int (int irq, void *dev_id, struct pt_regs *fp)
180 {
181     volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
182     unsigned char msr = rtc->msr & 0xc0;
183 
184     rtc->msr = msr | 0x20;		/* Ack the interrupt */
185 
186     return tick_handler(irq, dev_id, fp);
187 }
188 
189 /*
190  * Set up the RTC timer 1 to mode 2, so T1 output toggles every 5ms
191  * (40000 x 125ns).  It will interrupt every 10ms, when T1 goes low.
192  * So, when reading the elapsed time, you should read timer1,
193  * subtract it from 39999, and then add 40000 if T1 is high.
194  * That gives you the number of 125ns ticks in to the 10ms period,
195  * so divide by 8 to get the microsecond result.
196  */
197 
198 void bvme6000_sched_init (irqreturn_t (*timer_routine)(int, void *, struct pt_regs *))
199 {
200     volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
201     unsigned char msr = rtc->msr & 0xc0;
202 
203     rtc->msr = 0;	/* Ensure timer registers accessible */
204 
205     tick_handler = timer_routine;
206     if (request_irq(BVME_IRQ_RTC, bvme6000_timer_int, 0,
207 				"timer", bvme6000_timer_int))
208 	panic ("Couldn't register timer int");
209 
210     rtc->t1cr_omr = 0x04;	/* Mode 2, ext clk */
211     rtc->t1msb = 39999 >> 8;
212     rtc->t1lsb = 39999 & 0xff;
213     rtc->irr_icr1 &= 0xef;	/* Route timer 1 to INTR pin */
214     rtc->msr = 0x40;		/* Access int.cntrl, etc */
215     rtc->pfr_icr0 = 0x80;	/* Just timer 1 ints enabled */
216     rtc->irr_icr1 = 0;
217     rtc->t1cr_omr = 0x0a;	/* INTR+T1 active lo, push-pull */
218     rtc->t0cr_rtmr &= 0xdf;	/* Stop timers in standby */
219     rtc->msr = 0;		/* Access timer 1 control */
220     rtc->t1cr_omr = 0x05;	/* Mode 2, ext clk, GO */
221 
222     rtc->msr = msr;
223 
224     if (request_irq(BVME_IRQ_ABORT, bvme6000_abort_int, 0,
225 				"abort", bvme6000_abort_int))
226 	panic ("Couldn't register abort int");
227 }
228 
229 
230 /* This is always executed with interrupts disabled.  */
231 
232 /*
233  * NOTE:  Don't accept any readings within 5us of rollover, as
234  * the T1INT bit may be a little slow getting set.  There is also
235  * a fault in the chip, meaning that reads may produce invalid
236  * results...
237  */
238 
239 unsigned long bvme6000_gettimeoffset (void)
240 {
241     volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
242     volatile PitRegsPtr pit = (PitRegsPtr)BVME_PIT_BASE;
243     unsigned char msr = rtc->msr & 0xc0;
244     unsigned char t1int, t1op;
245     unsigned long v = 800000, ov;
246 
247     rtc->msr = 0;	/* Ensure timer registers accessible */
248 
249     do {
250 	ov = v;
251 	t1int = rtc->msr & 0x20;
252 	t1op  = pit->pcdr & 0x04;
253 	rtc->t1cr_omr |= 0x40;		/* Latch timer1 */
254 	v = rtc->t1msb << 8;		/* Read timer1 */
255 	v |= rtc->t1lsb;		/* Read timer1 */
256     } while (t1int != (rtc->msr & 0x20) ||
257 		t1op != (pit->pcdr & 0x04) ||
258 			abs(ov-v) > 80 ||
259 				v > 39960);
260 
261     v = 39999 - v;
262     if (!t1op)				/* If in second half cycle.. */
263 	v += 40000;
264     v /= 8;				/* Convert ticks to microseconds */
265     if (t1int)
266 	v += 10000;			/* Int pending, + 10ms */
267     rtc->msr = msr;
268 
269     return v;
270 }
271 
272 static unsigned char bcd2bin (unsigned char b)
273 {
274 	return ((b>>4)*10 + (b&15));
275 }
276 
277 static unsigned char bin2bcd (unsigned char b)
278 {
279 	return (((b/10)*16) + (b%10));
280 }
281 
282 
283 /*
284  * Looks like op is non-zero for setting the clock, and zero for
285  * reading the clock.
286  *
287  *  struct hwclk_time {
288  *         unsigned        sec;       0..59
289  *         unsigned        min;       0..59
290  *         unsigned        hour;      0..23
291  *         unsigned        day;       1..31
292  *         unsigned        mon;       0..11
293  *         unsigned        year;      00...
294  *         int             wday;      0..6, 0 is Sunday, -1 means unknown/don't set
295  * };
296  */
297 
298 int bvme6000_hwclk(int op, struct rtc_time *t)
299 {
300 	volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
301 	unsigned char msr = rtc->msr & 0xc0;
302 
303 	rtc->msr = 0x40;	/* Ensure clock and real-time-mode-register
304 				 * are accessible */
305 	if (op)
306 	{	/* Write.... */
307 		rtc->t0cr_rtmr = t->tm_year%4;
308 		rtc->bcd_tenms = 0;
309 		rtc->bcd_sec = bin2bcd(t->tm_sec);
310 		rtc->bcd_min = bin2bcd(t->tm_min);
311 		rtc->bcd_hr  = bin2bcd(t->tm_hour);
312 		rtc->bcd_dom = bin2bcd(t->tm_mday);
313 		rtc->bcd_mth = bin2bcd(t->tm_mon + 1);
314 		rtc->bcd_year = bin2bcd(t->tm_year%100);
315 		if (t->tm_wday >= 0)
316 			rtc->bcd_dow = bin2bcd(t->tm_wday+1);
317 		rtc->t0cr_rtmr = t->tm_year%4 | 0x08;
318 	}
319 	else
320 	{	/* Read....  */
321 		do {
322 			t->tm_sec  = bcd2bin(rtc->bcd_sec);
323 			t->tm_min  = bcd2bin(rtc->bcd_min);
324 			t->tm_hour = bcd2bin(rtc->bcd_hr);
325 			t->tm_mday = bcd2bin(rtc->bcd_dom);
326 			t->tm_mon  = bcd2bin(rtc->bcd_mth)-1;
327 			t->tm_year = bcd2bin(rtc->bcd_year);
328 			if (t->tm_year < 70)
329 				t->tm_year += 100;
330 			t->tm_wday = bcd2bin(rtc->bcd_dow)-1;
331 		} while (t->tm_sec != bcd2bin(rtc->bcd_sec));
332 	}
333 
334 	rtc->msr = msr;
335 
336 	return 0;
337 }
338 
339 /*
340  * Set the minutes and seconds from seconds value 'nowtime'.  Fail if
341  * clock is out by > 30 minutes.  Logic lifted from atari code.
342  * Algorithm is to wait for the 10ms register to change, and then to
343  * wait a short while, and then set it.
344  */
345 
346 int bvme6000_set_clock_mmss (unsigned long nowtime)
347 {
348 	int retval = 0;
349 	short real_seconds = nowtime % 60, real_minutes = (nowtime / 60) % 60;
350 	unsigned char rtc_minutes, rtc_tenms;
351 	volatile RtcPtr_t rtc = (RtcPtr_t)BVME_RTC_BASE;
352 	unsigned char msr = rtc->msr & 0xc0;
353 	unsigned long flags;
354 	volatile int i;
355 
356 	rtc->msr = 0;		/* Ensure clock accessible */
357 	rtc_minutes = bcd2bin (rtc->bcd_min);
358 
359 	if ((rtc_minutes < real_minutes
360 		? real_minutes - rtc_minutes
361 			: rtc_minutes - real_minutes) < 30)
362 	{
363 		local_irq_save(flags);
364 		rtc_tenms = rtc->bcd_tenms;
365 		while (rtc_tenms == rtc->bcd_tenms)
366 			;
367 		for (i = 0; i < 1000; i++)
368 			;
369 		rtc->bcd_min = bin2bcd(real_minutes);
370 		rtc->bcd_sec = bin2bcd(real_seconds);
371 		local_irq_restore(flags);
372 	}
373 	else
374 		retval = -1;
375 
376 	rtc->msr = msr;
377 
378 	return retval;
379 }
380 
381