arch/m68k/bvme6000/config.c

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