cpu/sh2/sh2.c

   1 #include <string.h>
   2 #include "sh2.h"
   3 #include "compiler.h"
   4
   5 #define I 0xf0
   6
   7 SH2 *sh2; // active sh2
   8
   9 int sh2_init(SH2 *sh2, int is_slave)
  10 {
  11         int ret = 0;
  12
  13         memset(sh2, 0, sizeof(*sh2));
  14         sh2->is_slave = is_slave;
  15 #ifdef DRC_SH2
  16         ret = sh2_drc_init(sh2);
  17 #endif
  18         return ret;
  19 }
  20
  21 void sh2_finish(SH2 *sh2)
  22 {
  23 #ifdef DRC_SH2
  24         sh2_drc_finish(sh2);
  25 #endif
  26 }
  27
  28 void sh2_reset(SH2 *sh2)
  29 {
  30         sh2->pc = p32x_sh2_read32(0, sh2);
  31         sh2->r[15] = p32x_sh2_read32(4, sh2);
  32         sh2->sr = I;
  33         sh2->vbr = 0;
  34         sh2->pending_int_irq = 0;
  35 }
  36
  37 void sh2_do_irq(SH2 *sh2, int level, int vector)
  38 {
  39         sh2->irq_callback(sh2->is_slave, level);
  40
  41         sh2->r[15] -= 4;
  42         p32x_sh2_write32(sh2->r[15], sh2->sr, sh2);     /* push SR onto stack */
  43         sh2->r[15] -= 4;
  44         p32x_sh2_write32(sh2->r[15], sh2->pc, sh2);     /* push PC onto stack */
  45
  46         /* set I flags in SR */
  47         sh2->sr = (sh2->sr & ~I) | (level << 4);
  48
  49         /* fetch PC */
  50         sh2->pc = p32x_sh2_read32(sh2->vbr + vector * 4, sh2);
  51
  52         /* 13 cycles at best */
  53         sh2->cycles_done += 13;
  54 //      sh2->icount -= 13;
  55 }
  56
  57 void sh2_irl_irq(SH2 *sh2, int level)
  58 {
  59         sh2->pending_irl = level;
  60         if (level > sh2->pending_int_irq)
  61                 sh2->pending_level = level;
  62         else
  63                 sh2->pending_level = sh2->pending_int_irq;
  64
  65         sh2->test_irq = 1;
  66 }
  67
  68 void sh2_internal_irq(SH2 *sh2, int level, int vector)
  69 {
  70         // FIXME: multiple internal irqs not handled..
  71         // assuming internal irqs never clear until accepted
  72         sh2->pending_int_irq = level;
  73         sh2->pending_int_vector = vector;
  74         if (level > sh2->pending_level)
  75                 sh2->pending_level = level;
  76
  77         sh2->test_irq = 1;
  78 }
  79