arch/m68k-amiga/kernel/amiga_irq.c

   1 /*
   2     copyright © 1995-2017, the aros development team. all rights reserved.
   3     $id$
   4
   5     desc: m68k-amiga IRQ handling
   6     lang: english
   7  */
   8
   9 #include <aros/kernel.h>
  10 #include <aros/asmcall.h>
  11
  12 #include <exec/resident.h>
  13 #include <exec/execbase.h>
  14
  15 #include <hardware/intbits.h>
  16
  17 #include "kernel_base.h"
  18 #include "kernel_intr.h"
  19 #include "kernel_syscall.h"
  20 #include "kernel_scheduler.h"
  21
  22 #include "m68k_exception.h"
  23 #include "amiga_irq.h"
  24
  25 #include "exec_intern.h"
  26
  27 /** Interrupts */
  28 #define INTENAR                 0x1c
  29 #define INTREQR                 0x1e
  30 #define INTENA                  0x9a
  31 #define INTREQ                  0x9c
  32
  33 /** DMA **/
  34 #define DMACON                  0x96
  35
  36 /** Display Control **/
  37 #define DIWSTRT 0x8e
  38 #define DIWSTOP 0x90
  39
  40 #define DIWSTRT_NTSC    0x2c81
  41 #define DIWSTOP_NTSC    0xf4c1
  42
  43 #define DIWSTRT_PAL     0x2c81
  44 #define DIWSTOP_PAL     0x2cc1
  45
  46 #define DDFSTRT 0x92
  47 #define DDFSTOP 0x94
  48
  49 #define DDFSTRT_LOW     0x0038
  50 #define DDFSTOP_LOW     0x00d0
  51
  52 #define DDFSTRT_HIGH    0x003c
  53 #define DDFSTOP_HIGH    0x00d4
  54
  55 static inline void custom_w(ULONG reg, UWORD val)
  56 {
  57         volatile UWORD *r = (void *)(0xdff000 + reg);
  58
  59         *r = val;
  60 }
  61
  62 static inline UWORD custom_r(ULONG reg)
  63 {
  64         volatile UWORD *r = (void *)(0xdff000 + reg);
  65
  66         return *r;
  67 }
  68
  69
  70 /* Here's how it's all laid out on the Amiga
  71  *    M68K Exception
  72  *      0       Reset: Initial SP
  73  *      1       Reset: Initial PC (NOTE: Really is SysBase!)
  74  *      2       Bus Error
  75  *      3       Address Error
  76  *      4       Illegal Instruction
  77  *      5       Divide by Zero
  78  *      6       CHK Instruction
  79  *      7       TRAPV Instruction
  80  *      8       Privileged Instruction
  81  *      9       Trace
  82  *      10      Line 1010 Emulator
  83  *      11      Line 1111 Emulator
  84  *      12      -
  85  *      13      -
  86  *      14      Format Error
  87  *      15      Uninitilaized Interrupt Vector
  88  *      16      -
  89  *      ..
  90  *      23      -
  91  *      24      Spurious Interrupt
  92  *      25      Level 1 Interrupt
  93  *                      Paula 0: Serial TX
  94  *                      Paula 1: Disk DMA done
  95  *                      Paula 2: Software Int
  96  *      26      Level 2 Interrupt
  97  *                      Paula 3: CIAA & IRQ2
  98  *      27      Level 3 Interrupt
  99  *                      Paula 4: Copper
 100  *                      Paula 5: Vert Blank
 101  *                      Paula 6: Blitter
 102  *      28      Level 4 Interrupt
 103  *                      Paula 7: Audio 0
 104  *                      Paula 8: Audio 1
 105  *                      Paula 9: Audio 2
 106  *                      Paula 10: Audio 3
 107  *      29      Level 5 Interrupt
 108  *                      Paula 11: Serial RX
 109  *                      Paula 12: Disk Sync
 110  *      30      Level 6 Interrupt
 111  *                      Paula 13: External
 112  *                      Paula 14: CIAB & IRQ6
 113  *      31      Level 7 Interrupt
 114  *                      Paula 15: NMI
 115  *      32      TRAP #0
 116  *      ..
 117  *      47      TRAP #15
 118  *      48      -
 119  *      ..
 120  *      63      -
 121  *      64      User 1
 122  *      ..
 123  *      255     User 191
 124  */
 125
 126 #define PAULA_IRQ_CHECK(valid_mask) \
 127     const UWORD irq_mask = valid_mask; \
 128     UWORD intenar = custom_r(INTENAR); \
 129     if (!(intenar & INTF_INTEN)) \
 130         return TRUE; \
 131     UWORD mask = intenar & custom_r(INTREQR) & (irq_mask); \
 132     do {
 133
 134 #define PAULA_IRQ_ACK(clear_mask) \
 135     custom_w(INTREQ, mask & (clear_mask));
 136
 137 #define PAULA_IRQ_HANDLE(irq) \
 138         if ((mask) & (1 << (irq))) { \
 139             core_Cause(irq, mask); \
 140         }
 141
 142 #define PAULA_IRQ_EXIT()        \
 143         /* mask = custom_r(INTENAR) & custom_r(INTREQR) & (irq_mask); */ \
 144     } while (0); \
 145     /* Call Exec/ExitIntr */    \
 146     return TRUE;
 147
 148 #define DECLARE_TrapCode(handler) \
 149     BOOL handler(VOID); \
 150     VOID handler##_TrapCode(ULONG Id); \
 151     asm ( \
 152             "   .global " #handler "_TrapCode\n" \
 153             "   .func " #handler "_TrapCode\n" \
 154             #handler "_TrapCode:\n" \
 155             "   addq.l  #4,%sp\n"       /* Drop the ID */   \
 156             "   movem.l %d0/%d1/%a0/%a1/%a5/%a6,%sp@-\n"    \
 157             "   jsr     " #handler "\n" \
 158             "   tst.w   %d0\n"          \
 159             "   beq     0f\n"           \
 160             "   jmp     Exec_6_ExitIntr\n" \
 161             "0:\n" \
 162             "   movem.l %sp@+,%d0/%d1/%a0/%a1/%a5/%a6\n" \
 163             "   rte\n" \
 164             "   .endfunc\n" \
 165         ); \
 166
 167 /* AOS interrupt handlers will clear INTREQ before executing interrupt code,
 168  * servers will clear INTREQ after whole server chain has been executed.
 169  */
 170
 171 DECLARE_TrapCode(Amiga_Level_1);
 172 DECLARE_TrapCode(Amiga_Level_2);
 173 DECLARE_TrapCode(Amiga_Level_3);
 174 DECLARE_TrapCode(Amiga_Level_4);
 175 DECLARE_TrapCode(Amiga_Level_5);
 176 DECLARE_TrapCode(Amiga_Level_6);
 177 DECLARE_TrapCode(Amiga_Level_7);
 178
 179 BOOL Amiga_Level_1(VOID)
 180 {
 181     /* Paula IRQs 0 - Serial port TX done
 182      *            1 - Disk DMA finished
 183      *            2 - SoftInt
 184      */
 185
 186     PAULA_IRQ_CHECK(INTF_SOFTINT | INTF_DSKBLK | INTF_TBE);
 187
 188     /* SOFTINT is cleared by SOFTINT handler, we can't clear it
 189      * here anymore because SOFTINT handler may call Cause() internally
 190      */
 191     PAULA_IRQ_ACK(INTF_DSKBLK | INTF_TBE);
 192
 193     PAULA_IRQ_HANDLE(INTB_TBE);
 194     PAULA_IRQ_HANDLE(INTB_DSKBLK);
 195     PAULA_IRQ_HANDLE(INTB_SOFTINT);
 196
 197     PAULA_IRQ_EXIT();
 198 }
 199
 200 BOOL Amiga_Level_2(VOID)
 201 {
 202     /* Paula IRQs 3 - CIA-A
 203      */
 204     PAULA_IRQ_CHECK(INTF_PORTS);
 205
 206     PAULA_IRQ_HANDLE(INTB_PORTS);
 207
 208     PAULA_IRQ_ACK(INTF_PORTS);
 209
 210     PAULA_IRQ_EXIT();
 211 }
 212
 213 BOOL Amiga_Level_3(VOID)
 214 {
 215     /* Paula IRQs 4 - Copper
 216      *            5 - Vert Blank
 217      *            6 - Blitter
 218      */
 219     PAULA_IRQ_CHECK(INTF_COPER | INTF_VERTB | INTF_BLIT);
 220
 221     PAULA_IRQ_HANDLE(INTB_COPER);
 222     PAULA_IRQ_HANDLE(INTB_VERTB);
 223
 224     PAULA_IRQ_ACK(INTF_COPER | INTF_VERTB | INTF_BLIT);
 225
 226     PAULA_IRQ_HANDLE(INTB_BLIT);
 227
 228     PAULA_IRQ_EXIT();
 229 }
 230
 231 BOOL Amiga_Level_4(VOID)
 232 {
 233     /* Paula IRQs  7 - Audio 0
 234      *             8 - Audio 1
 235      *             9 - Audio 2
 236      *            10 - Audio 3
 237      */
 238     PAULA_IRQ_CHECK(INTF_AUD0 | INTF_AUD1 | INTF_AUD2 | INTF_AUD3);
 239
 240     PAULA_IRQ_ACK(INTF_AUD0 | INTF_AUD1 | INTF_AUD2 | INTF_AUD3);
 241
 242     PAULA_IRQ_HANDLE(INTB_AUD0);
 243     PAULA_IRQ_HANDLE(INTB_AUD1);
 244     PAULA_IRQ_HANDLE(INTB_AUD2);
 245     PAULA_IRQ_HANDLE(INTB_AUD3);
 246
 247     PAULA_IRQ_EXIT();
 248 }
 249
 250 BOOL Amiga_Level_5(VOID)
 251 {
 252     /* Paula IRQs  11 - Serial RX
 253      *             12 - Disk Sync
 254      */
 255     PAULA_IRQ_CHECK(INTF_RBF | INTF_DSKSYNC);
 256
 257     PAULA_IRQ_ACK(INTF_RBF | INTF_DSKSYNC);
 258
 259     PAULA_IRQ_HANDLE(INTB_RBF);
 260     PAULA_IRQ_HANDLE(INTB_DSKSYNC);
 261
 262     PAULA_IRQ_EXIT();
 263 }
 264
 265 BOOL Amiga_Level_6(VOID)
 266 {
 267     /* Paula IRQ  13 - CIA-B & IRQ6
 268      *            14 - INTEN (manually setting INTEN bit in INTREQ triggers it)
 269      */
 270     PAULA_IRQ_CHECK(INTF_EXTER | INTF_INTEN);
 271
 272     PAULA_IRQ_HANDLE(INTB_EXTER);
 273     PAULA_IRQ_HANDLE(INTB_INTEN);
 274
 275     PAULA_IRQ_ACK(INTF_EXTER);
 276
 277     PAULA_IRQ_EXIT();
 278 }
 279
 280 BOOL Amiga_Level_7(VOID)
 281 {
 282     /* NMI - no way around it.
 283      */
 284     const UWORD mask = (1 << 15);
 285
 286     PAULA_IRQ_HANDLE(15);
 287
 288     /* Don't reschedule on the way out - so don't
 289      * call PAULA_IRQ_EXIT()
 290      */
 291     return FALSE;
 292 }
 293
 294 const struct M68KException AmigaExceptionTable[] = {
 295         { .Id =  25, .Handler = Amiga_Level_1_TrapCode },
 296         { .Id =  26, .Handler = Amiga_Level_2_TrapCode },
 297         { .Id =  27, .Handler = Amiga_Level_3_TrapCode },
 298         { .Id =  28, .Handler = Amiga_Level_4_TrapCode },
 299         { .Id =  29, .Handler = Amiga_Level_5_TrapCode },
 300         { .Id =  30, .Handler = Amiga_Level_6_TrapCode },
 301         { .Id =  31, .Handler = Amiga_Level_7_TrapCode },
 302         { .Id =   0, }
 303 };
 304
 305 void AmigaIRQInit(struct ExecBase *SysBase)
 306 {
 307         /* Disable all interrupts */
 308         custom_w(INTENA, 0x7fff);
 309         /* Clear any requests */
 310         custom_w(INTREQ, 0x7fff);
 311
 312         M68KExceptionInit(AmigaExceptionTable, SysBase);
 313
 314         /* Enable DMA */
 315         custom_w(DMACON, 0x8240);
 316
 317         /* Set up Vert. & Horiz. interval
 318          * PAL 320x200x4
 319          */
 320         custom_w(DIWSTRT, DIWSTRT_PAL);
 321         custom_w(DIWSTOP, DIWSTOP_PAL);
 322         custom_w(DDFSTRT, DDFSTRT_LOW);
 323         custom_w(DDFSTOP, DDFSTOP_LOW);
 324
 325         /* Enable Vertical Blank and SoftInt */
 326         custom_w(INTENA, INTF_SETCLR | INTF_VERTB | INTF_SOFTINT);
 327
 328         /* IRQs will be enabled by the first Enable() in Exec's init */
 329 }