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