arch/m68k/mac/via6522.c

   1 /*
   2  *      6522 Versatile Interface Adapter (VIA)
   3  *
   4  *      There are two of these on the Mac II. Some IRQ's are vectored
   5  *      via them as are assorted bits and bobs - eg rtc, adb.
   6  */
   7
   8 #include <linux/types.h>
   9 #include <linux/kernel.h>
  10 #include <linux/mm.h>
  11
  12 #include <asm/macintosh.h>
  13 #include <asm/macints.h>
  14 #include "via6522.h"
  15 #include "psc.h"
  16
  17 volatile unsigned char *via1=(unsigned char *)VIABASE;
  18 volatile unsigned char *via2=(unsigned char *)VIABASE2;
  19 volatile unsigned char *psc=(unsigned char *)PSCBASE;
  20
  21 unsigned char via1_clock, via1_datab;
  22
  23 static int rbv=0;
  24 static int oss=0;
  25
  26 extern void adb_interrupt(int slot, void *via, struct pt_regs *regs);
  27
  28 /*
  29  * hardware reset vector
  30  */
  31 static void (*rom_reset)(void);
  32
  33 /*
  34  * Timer defs.
  35  */
  36 #define MAC_CLOCK_TICK          (783300/HZ)     /* ticks per HZ */
  37 #define MAC_CLOCK_LOW           (MAC_CLOCK_TICK&0xFF)
  38 #define MAC_CLOCK_HIGH          (MAC_CLOCK_TICK>>8)
  39
  40
  41 void via_init_clock(void (*func)(int, void *, struct pt_regs *))
  42 {
  43         unsigned char c;
  44
  45         switch(macintosh_config->via_type)
  46         {
  47                 /*
  48                  *      CI, SI, VX, LC
  49                  */
  50                 case MAC_VIA_IIci:
  51                         via1=(void *)0x50F00000;
  52                         via2=(void *)0x50F26000;
  53                         rbv=1;
  54                         if (macintosh_config->ident == MAC_MODEL_IIFX) {
  55                                 via2=(void *)0x50F1A000;
  56                                 oss=1;
  57                         }
  58                         break;
  59                 /*
  60                  *      Quadra and early MacIIs agree on the VIA locations
  61                  */
  62                 case MAC_VIA_QUADRA:
  63                 case MAC_VIA_II:
  64                         via1=(void *)0x50F00000;
  65                         via2=(void *)0x50F02000;
  66                         break;
  67                 default:
  68         }
  69         via1_clock=via_read(via1, vACR);
  70         via1_datab=via_read(via1, vBufB);
  71
  72         /*
  73          * Tell what MacOS left us with
  74          */
  75
  76         printk("via_init: boot via1 acr=%X pcr=%X buf_a=%X dir_a=%X buf_b=%X dir_b=%X \n",
  77                 (int)via1_clock, (int)via_read(via1, vPCR),
  78                 (int)via_read(via1, vBufA), (int)via_read(via1, vDirA),
  79                 (int)via_read(via1, vBufB), (int)via_read(via1, vDirB));
  80
  81         if (rbv == 0)
  82                 printk("via_init: boot via2 acr=%X pcr=%X buf_a=%X dir_a=%X buf_b=%X dir_b=%X \n",
  83                         (int)via_read(via2, vACR), (int)via_read(via2, vPCR),
  84                         (int)via_read(via2, vBufA), (int)via_read(via2, vDirA),
  85                         (int)via_read(via2, vBufB), (int)via_read(via2, vDirB));
  86
  87         /*
  88          *      Shut it down
  89          */
  90
  91         via_write(via1,vIER, 0x7F);
  92
  93         /*
  94          *      Kill the timers
  95          */
  96
  97         via_write(via1,vT1LL,0);
  98         via_write(via1,vT1LH,0);
  99         via_write(via1,vT1CL,0);
 100         via_write(via1,vT1CH,0);
 101         via_write(via1,vT2CL,0);
 102         via_write(via1,vT2CH,0);
 103
 104         /*
 105          *      Now do via2
 106          */
 107
 108         if(rbv==0)
 109         {
 110                 via_write(via2,vT1LL,0);
 111                 via_write(via2,vT1LH,0);
 112                 via_write(via2,vT1CL,0);
 113                 via_write(via2,vT1CH,0);
 114                 via_write(via2,vT2CL,0);
 115                 via_write(via2,vT2CH,0);
 116                 via_write(via2,vIER, 0x7F);
 117         }
 118         else if (oss==0)
 119         {
 120                 /*
 121                  *      Init the RBV chip a bit
 122                  */
 123
 124                 via_write(via2, rIER,0x7F);
 125         }
 126
 127         /*
 128          *      Disable the timer latches
 129          */
 130
 131         c=via_read(via1,vACR);
 132         via_write(via1,vACR,c&0x3F);
 133
 134         if(rbv==0)
 135         {
 136                 c=via_read(via2,vACR);
 137                 via_write(via2,vACR,c&0x3F);
 138         }
 139
 140         /*
 141          *      Now start the clock - we want 100Hz
 142          */
 143
 144         via_write(via1,vACR,via_read(via1,vACR)|0x40);
 145
 146         via_write(via1,vT1LL, MAC_CLOCK_LOW);
 147         via_write(via1,vT1LH, MAC_CLOCK_HIGH);
 148         via_write(via1,vT1CL, MAC_CLOCK_LOW);
 149         via_write(via1,vT1CH, MAC_CLOCK_HIGH);
 150
 151         /*
 152          *      And enable its interrupt
 153          */
 154
 155         request_irq(IRQ_MAC_TIMER_1, func, IRQ_FLG_LOCK, "timer", func);
 156
 157         /*
 158          * SE/30: disable video int.
 159          * XXX: testing for SE/30 VBL
 160          */
 161
 162         if (macintosh_config->ident == MAC_MODEL_SE30) {
 163                 c = via_read(via1, vBufB);
 164                 via_write(via1, vBufB, c|(0x40));
 165                 c = via_read(via1, vDirB);
 166                 via_write(via1, vDirB, c|(0x40));
 167         }
 168
 169 #if 0 /* gone to mac_init_IRQ */
 170         /*
 171          * Set vPCR for SCSI interrupts.
 172          *
 173          * That is: CA1 negative edge int., CA2 indep., positive edge int.;
 174          *          CB1 negative edge int., CB2 indep., positive edge int..
 175          */
 176         via_write(via2,vPCR, 0x66);
 177 #endif
 178
 179 }
 180
 181 /*
 182  * get time offset between scheduling timer ticks
 183  * Code stolen from arch/m68k/atari/time.c; underflow check probably
 184  * wrong.
 185  */
 186 #define TICK_SIZE 10000
 187
 188 /* This is always executed with interrupts disabled.  */
 189 unsigned long mac_gettimeoffset (void)
 190 {
 191   unsigned long ticks, offset = 0;
 192
 193   /* read VIA1 timer 2 current value */
 194   ticks = via_read(via1, vT1CL) + (via_read(via1, vT1CH)<<8);
 195   /* The probability of underflow is less than 2% */
 196   if (ticks > MAC_CLOCK_TICK - MAC_CLOCK_TICK / 50)
 197     /* Check for pending timer interrupt in VIA1 IFR */
 198     if (via_read(via1, vIFR) & 0x40)
 199       offset = TICK_SIZE;
 200
 201   ticks = MAC_CLOCK_TICK - ticks;
 202   ticks = ticks * 10000L / MAC_CLOCK_TICK;
 203
 204   return ticks + offset;
 205 }
 206
 207 /*
 208  *      PSC (AV Macs; level 3-6): initialize interrupt enable registers
 209  */
 210
 211 void psc_init(void)
 212 {
 213         via_write(psc, pIER3, 0x01);
 214         via_write(psc, pIER4, 0x09);
 215         via_write(psc, pIER4, 0x86);
 216         via_write(psc, pIER5, 0x03);
 217         via_write(psc, pIER6, 0x07);
 218 }
 219
 220 /*
 221  *      The power switch - yes its software!
 222  */
 223
 224 void mac_poweroff(void)
 225 {
 226 #if 0
 227         /*
 228          * Powerdown, for the Macs that support it
 229          */
 230         if(rbv) {
 231                 via_write(via2, rBufB, via_read(via2, rBufB)&~0x04);
 232         } else {
 233                 /* Direction of vDirB is output */
 234                 via_write(via2,vDirB,via_read(via2,vDirB)|0x04);
 235                 /* Send a value of 0 on that line */
 236                 via_write(via2,vBufB,via_read(via2,vBufB)&~0x04);
 237         }
 238 #endif
 239         /* We should never make it this far... */
 240         /* XXX - delay do we need to spin here ? */
 241         while(1);       /* Just in case .. */
 242 }
 243
 244 /*
 245  * Not all Macs support software power down; for the rest, just
 246  * try the ROM reset vector ...
 247  */
 248 void mac_reset(void)
 249 {
 250         unsigned long flags;
 251         unsigned long *reset_hook;
 252
 253         save_flags(flags);
 254         cli();
 255
 256 #if 0   /* need ROMBASE in booter */
 257 #if 0   /* works on some */
 258         rom_reset = (boot_info.bi_mac.rombase + 0xa);
 259 #else   /* testing, doesn't work on SE/30 either */
 260         reset_hook = (unsigned long *) (boot_info.bi_mac.rombase + 0x4);
 261         printk("ROM reset hook: %p\n", *reset_hook);
 262         rom_reset = *reset_hook;
 263 #endif
 264         rom_reset();
 265 #endif
 266         restore_flags(flags);
 267
 268         /* We never make it this far... */
 269         printk(" reboot failed, reboot manually!\n");
 270         /* XXX - delay do we need to spin here ? */
 271         while(1);       /* Just in case .. */
 272 }
 273
 274 /*
 275  *      Set up the keyboard
 276  */
 277
 278 void via_setup_keyboard(void)
 279 {
 280 #if 0 /* moved to adb */
 281         via1_func_tab.vector[2]=adb_interrupt;
 282 #else
 283         request_irq(IRQ_MAC_ADB, adb_interrupt, IRQ_FLG_LOCK, "adb interrupt",
 284                     adb_interrupt);
 285 #endif
 286 }
 287
 288 /*
 289  *      Floppy hook
 290  */
 291
 292 void via1_set_head(int head)
 293 {
 294         if(head==0)
 295                 via_write(via1, vBufA, via_read(via1, vBufA)&~0x20);
 296         else
 297                 via_write(via1, vBufA, via_read(via1, vBufA)|0x20);
 298 }
 299
 300 void nubus_init_via(void)
 301 {
 302         if (rbv) {
 303                 if (oss==0) {
 304                         via_write(via2, rBufB, via_read(via2, rBufB)|0x02);
 305                         via_write(via2, rIER, 0x82);    /* Interrupts on */
 306                 }
 307         } else {
 308                 /* Assert the nubus active */
 309                 via_write(via2, vDirB, via_read(via2, vDirB)|0x02);
 310                 via_write(via2, vBufB, via_read(via2, vBufB)|0x02);
 311                 /* Make the nubus interrupt source register all output (disable) */
 312                 /* via_write(via2, vDirA, 0xFF); */
 313                 via_write(via2, vIER, 0x82);    /* Interrupts on */
 314         }
 315
 316         printk("nubus_init_via: via1 acr=%X datab=%X pcr=%X\n",
 317                 (int)via_read(via1, vACR), (int)via_read(via1, vBufB),
 318                 (int)via_read(via1, vPCR));
 319
 320         if (rbv==0)
 321                 printk("nubus_init_via: via2 acr=%X datab=%X pcr=%X\n",
 322                         (int)via_read(via2, vACR), (int)via_read(via2, vBufB),
 323                         (int)via_read(via2, vPCR));
 324 }