arch/m68k-amiga/kernel/amiga_irq.c

   1 /*
   2     copyright © 1995-2010, 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 #include <defines/kernel.h>
  15
  16 #include <hardware/intbits.h>
  17
  18 #include "kernel_base.h"
  19 #include "kernel_intr.h"
  20 #include "kernel_syscall.h"
  21 #include "kernel_scheduler.h"
  22
  23 #include "m68k_exception.h"
  24 #include "amiga_irq.h"
  25
  26 #include "exec_intern.h"
  27
  28 /** Interrupts */
  29 #define INTENAR                 0x1c
  30 #define INTREQR                 0x1e
  31 #define INTENA                  0x9a
  32 #define INTREQ                  0x9c
  33
  34 /** DMA **/
  35 #define DMACON                  0x96
  36
  37 /** Display Control **/
  38 #define DIWSTRT 0x8e
  39 #define DIWSTOP 0x90
  40
  41 #define DIWSTRT_NTSC    0x2c81
  42 #define DIWSTOP_NTSC    0xf4c1
  43
  44 #define DIWSTRT_PAL     0x2c81
  45 #define DIWSTOP_PAL     0x2cc1
  46
  47 #define DDFSTRT 0x92
  48 #define DDFSTOP 0x94
  49
  50 #define DDFSTRT_LOW     0x0038
  51 #define DDFSTOP_LOW     0x00d0
  52
  53 #define DDFSTRT_HIGH    0x003c
  54 #define DDFSTOP_HIGH    0x00d4
  55
  56 static inline void custom_w(ULONG reg, UWORD val)
  57 {
  58         volatile UWORD *r = (void *)(0xdff000 + reg);
  59
  60         *r = val;
  61 }
  62
  63 static inline UWORD custom_r(ULONG reg)
  64 {
  65         volatile UWORD *r = (void *)(0xdff000 + reg);
  66
  67         return *r;
  68 }
  69
  70
  71 /* Here's how it's all laid out on the Amiga
  72  *    M68K Exception
  73  *      0       Reset: Initial SP
  74  *      1       Reset: Initial PC (NOTE: Really is SysBase!)
  75  *      2       Bus Error
  76  *      3       Address Error
  77  *      4       Illegal Instruction
  78  *      5       Divide by Zero
  79  *      6       CHK Instruction
  80  *      7       TRAPV Instruction
  81  *      8       Privileged Instruction
  82  *      9       Trace
  83  *      10      Line 1010 Emulator
  84  *      11      Line 1111 Emulator
  85  *      12      -
  86  *      13      -
  87  *      14      Format Error
  88  *      15      Uninitilaized Interrupt Vector
  89  *      16      -
  90  *      ..
  91  *      23      -
  92  *      24      Spurious Interrupt
  93  *      25      Level 1 Interrupt
  94  *                      Paula 0: Serial TX
  95  *                      Paula 1: Disk DMA done
  96  *                      Paula 2: Software Int
  97  *      26      Level 2 Interrupt
  98  *                      Paula 3: CIAA & IRQ2
  99  *      27      Level 3 Interrupt
 100  *                      Paula 4: Copper
 101  *                      Paula 5: Vert Blank
 102  *                      Paula 6: Blitter
 103  *      28      Level 4 Interrupt
 104  *                      Paula 7: Audio 0
 105  *                      Paula 8: Audio 1
 106  *                      Paula 9: Audio 2
 107  *                      Paula 10: Audio 3
 108  *      29      Level 5 Interrupt
 109  *                      Paula 11: Serial RX
 110  *                      Paula 12: Disk Sync
 111  *      30      Level 6 Interrupt
 112  *                      Paula 13: External
 113  *                      Paula 14: CIAB & IRQ6
 114  *      31      Level 7 Interrupt
 115  *                      Paula 15: NMI
 116  *      32      TRAP #0
 117  *      ..
 118  *      47      TRAP #15
 119  *      48      -
 120  *      ..
 121  *      63      -
 122  *      64      User 1
 123  *      ..
 124  *      255     User 191
 125  */
 126
 127 #define PAULA_IRQ_CHECK(valid_mask) \
 128     const UWORD irq_mask = valid_mask; \
 129     UWORD intenar = custom_r(INTENAR); \
 130     if (!(intenar & INTF_INTEN)) \
 131         return TRUE; \
 132     UWORD mask = intenar & custom_r(INTREQR) & (irq_mask); \
 133     do {
 134
 135 #define PAULA_IRQ_ACK(clear_mask) \
 136     custom_w(INTREQ, mask & (clear_mask));
 137
 138 #define PAULA_IRQ_HANDLE(irq) \
 139         if ((mask) & (1 << (irq))) { \
 140             core_Cause(irq, mask); \
 141         }
 142
 143 #define PAULA_IRQ_EXIT()        \
 144         /* mask = custom_r(INTENAR) & custom_r(INTREQR) & (irq_mask); */ \
 145     } while (0); \
 146     /* Call Exec/ExitIntr */    \
 147     return TRUE;
 148
 149 #define DECLARE_TrapCode(handler) \
 150     BOOL handler(VOID); \
 151     VOID handler##_TrapCode(ULONG Id); \
 152     asm ( \
 153             "   .global " #handler "_TrapCode\n" \
 154             "   .func " #handler "_TrapCode\n" \
 155             #handler "_TrapCode:\n" \
 156             "   addq.l  #4,%sp\n"       /* Drop the ID */   \
 157             "   movem.l %d0/%d1/%a0/%a1/%a5/%a6,%sp@-\n"    \
 158             "   jsr     " #handler "\n" \
 159             "   tst.w   %d0\n"          \
 160             "   beq     0f\n"           \
 161             "   jmp     Exec_6_ExitIntr\n" \
 162             "0:\n" \
 163             "   movem.l %sp@+,%d0/%d1/%a0/%a1/%a5/%a6\n" \
 164             "   rte\n" \
 165             "   .endfunc\n" \
 166         ); \
 167
 168 /* AOS interrupt handlers will clear INTREQ before executing interrupt code,
 169  * servers will clear INTREQ after whole server chain has been executed.
 170  */
 171
 172 DECLARE_TrapCode(Amiga_Level_1);
 173 DECLARE_TrapCode(Amiga_Level_2);
 174 DECLARE_TrapCode(Amiga_Level_3);
 175 DECLARE_TrapCode(Amiga_Level_4);
 176 DECLARE_TrapCode(Amiga_Level_5);
 177 DECLARE_TrapCode(Amiga_Level_6);
 178 DECLARE_TrapCode(Amiga_Level_7);
 179
 180 BOOL Amiga_Level_1(VOID)
 181 {
 182     /* Paula IRQs 0 - Serial port TX done
 183      *            1 - Disk DMA finished
 184      *            2 - SoftInt
 185      */
 186
 187     PAULA_IRQ_CHECK(INTF_SOFTINT | INTF_DSKBLK | INTF_TBE);
 188
 189     /* SOFTINT is cleared by SOFTINT handler, we can't clear it
 190      * here anymore because SOFTINT handler may call Cause() internally
 191      */
 192     PAULA_IRQ_ACK(INTF_DSKBLK | INTF_TBE);
 193
 194     PAULA_IRQ_HANDLE(INTB_TBE);
 195     PAULA_IRQ_HANDLE(INTB_DSKBLK);
 196     PAULA_IRQ_HANDLE(INTB_SOFTINT);
 197
 198     PAULA_IRQ_EXIT();
 199 }
 200
 201 BOOL Amiga_Level_2(VOID)
 202 {
 203     /* Paula IRQs 3 - CIA-A
 204      */
 205     PAULA_IRQ_CHECK(INTF_PORTS);
 206
 207     PAULA_IRQ_HANDLE(INTB_PORTS);
 208
 209     PAULA_IRQ_ACK(INTF_PORTS);
 210
 211     PAULA_IRQ_EXIT();
 212 }
 213
 214 BOOL Amiga_Level_3(VOID)
 215 {
 216     /* Paula IRQs 4 - Copper
 217      *            5 - Vert Blank
 218      *            6 - Blitter
 219      */
 220     PAULA_IRQ_CHECK(INTF_COPER | INTF_VERTB | INTF_BLIT);
 221
 222     PAULA_IRQ_HANDLE(INTB_COPER);
 223     PAULA_IRQ_HANDLE(INTB_VERTB);
 224
 225     PAULA_IRQ_ACK(INTF_COPER | INTF_VERTB | INTF_BLIT);
 226
 227     PAULA_IRQ_HANDLE(INTB_BLIT);
 228
 229     PAULA_IRQ_EXIT();
 230 }
 231
 232 BOOL Amiga_Level_4(VOID)
 233 {
 234     /* Paula IRQs  7 - Audio 0
 235      *             8 - Audio 1
 236      *             9 - Audio 2
 237      *            10 - Audio 3
 238      */
 239     PAULA_IRQ_CHECK(INTF_AUD0 | INTF_AUD1 | INTF_AUD2 | INTF_AUD3);
 240
 241     PAULA_IRQ_ACK(INTF_AUD0 | INTF_AUD1 | INTF_AUD2 | INTF_AUD3);
 242
 243     PAULA_IRQ_HANDLE(INTB_AUD0);
 244     PAULA_IRQ_HANDLE(INTB_AUD1);
 245     PAULA_IRQ_HANDLE(INTB_AUD2);
 246     PAULA_IRQ_HANDLE(INTB_AUD3);
 247
 248     PAULA_IRQ_EXIT();
 249 }
 250
 251 BOOL Amiga_Level_5(VOID)
 252 {
 253     /* Paula IRQs  11 - Serial RX
 254      *             12 - Disk Sync
 255      */
 256     PAULA_IRQ_CHECK(INTF_RBF | INTF_DSKSYNC);
 257
 258     PAULA_IRQ_ACK(INTF_RBF | INTF_DSKSYNC);
 259
 260     PAULA_IRQ_HANDLE(INTB_RBF);
 261     PAULA_IRQ_HANDLE(INTB_DSKSYNC);
 262
 263     PAULA_IRQ_EXIT();
 264 }
 265
 266 BOOL Amiga_Level_6(VOID)
 267 {
 268     /* Paula IRQ  13 - CIA-B & IRQ6
 269      *            14 - INTEN (manually setting INTEN bit in INTREQ triggers it)
 270      */
 271     PAULA_IRQ_CHECK(INTF_EXTER | INTF_INTEN);
 272
 273     PAULA_IRQ_HANDLE(INTB_EXTER);
 274     PAULA_IRQ_HANDLE(INTB_INTEN);
 275
 276     PAULA_IRQ_ACK(INTF_EXTER);
 277
 278     PAULA_IRQ_EXIT();
 279 }
 280
 281 BOOL Amiga_Level_7(VOID)
 282 {
 283     /* NMI - no way around it.
 284      */
 285     const UWORD mask = (1 << 15);
 286
 287     PAULA_IRQ_HANDLE(15);
 288
 289     /* Don't reschedule on the way out - so don't
 290      * call PAULA_IRQ_EXIT()
 291      */
 292     return FALSE;
 293 }
 294
 295 const struct M68KException AmigaExceptionTable[] = {
 296         { .Id =  25, .Handler = Amiga_Level_1_TrapCode },
 297         { .Id =  26, .Handler = Amiga_Level_2_TrapCode },
 298         { .Id =  27, .Handler = Amiga_Level_3_TrapCode },
 299         { .Id =  28, .Handler = Amiga_Level_4_TrapCode },
 300         { .Id =  29, .Handler = Amiga_Level_5_TrapCode },
 301         { .Id =  30, .Handler = Amiga_Level_6_TrapCode },
 302         { .Id =  31, .Handler = Amiga_Level_7_TrapCode },
 303         { .Id =   0, }
 304 };
 305
 306 void AmigaIRQInit(struct ExecBase *SysBase)
 307 {
 308         /* Disable all interrupts */
 309         custom_w(INTENA, 0x7fff);
 310         /* Clear any requests */
 311         custom_w(INTREQ, 0x7fff);
 312
 313         M68KExceptionInit(AmigaExceptionTable, SysBase);
 314
 315         /* Enable DMA */
 316         custom_w(DMACON, 0x8240);
 317
 318         /* Set up Vert. & Horiz. interval
 319          * PAL 320x200x4
 320          */
 321         custom_w(DIWSTRT, DIWSTRT_PAL);
 322         custom_w(DIWSTOP, DIWSTOP_PAL);
 323         custom_w(DDFSTRT, DDFSTRT_LOW);
 324         custom_w(DDFSTOP, DDFSTOP_LOW);
 325
 326         /* Enable Vertical Blank and SoftInt */
 327         custom_w(INTENA, INTF_SETCLR | INTF_VERTB | INTF_SOFTINT);
 328
 329         /* IRQs will be enabled by the first Enable() in Exec's init */
 330 }