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
  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(irqreturn_t (*handler)(int, void *, struct pt_regs *));
  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 irqreturn_t (*tick_handler)(int, void *, struct pt_regs *);
  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, struct pt_regs *fp)
 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, struct pt_regs *fp)
 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, fp);
 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 (irqreturn_t (*timer_routine)(int, void *, struct pt_regs *))
 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