cpu/sh2/sh2.c

   1 #include <string.h>
   2 #include "sh2.h"
   3 #include "compiler.h"
   4
   5 #define I 0xf0
   6
   7 int sh2_init(SH2 *sh2, int is_slave)
   8 {
   9         int ret = 0;
  10
  11         memset(sh2, 0, sizeof(*sh2));
  12         sh2->is_slave = is_slave;
  13 #ifdef DRC_SH2
  14         ret = sh2_drc_init(sh2);
  15 #endif
  16         return ret;
  17 }
  18
  19 void sh2_finish(SH2 *sh2)
  20 {
  21 #ifdef DRC_SH2
  22         sh2_drc_finish(sh2);
  23 #endif
  24 }
  25
  26 void sh2_reset(SH2 *sh2)
  27 {
  28         sh2->pc = p32x_sh2_read32(0, sh2->is_slave);
  29         sh2->r[15] = p32x_sh2_read32(4, sh2->is_slave);
  30         sh2->sr = I;
  31         sh2->vbr = 0;
  32         sh2->pending_int_irq = 0;
  33 }
  34
  35 static void sh2_do_irq(SH2 *sh2, int level, int vector)
  36 {
  37         sh2->irq_callback(sh2->is_slave, level);
  38
  39         sh2->r[15] -= 4;
  40         p32x_sh2_write32(sh2->r[15], sh2->sr, sh2->is_slave);   /* push SR onto stack */
  41         sh2->r[15] -= 4;
  42         p32x_sh2_write32(sh2->r[15], sh2->pc, sh2->is_slave);   /* push PC onto stack */
  43
  44         /* set I flags in SR */
  45         sh2->sr = (sh2->sr & ~I) | (level << 4);
  46
  47         /* fetch PC */
  48         sh2->pc = p32x_sh2_read32(sh2->vbr + vector * 4, sh2->is_slave);
  49
  50         /* 13 cycles at best */
  51         sh2->cycles_done += 13;
  52 //      sh2->icount -= 13;
  53 }
  54
  55 void sh2_irl_irq(SH2 *sh2, int level)
  56 {
  57         sh2->pending_irl = level;
  58         if (level <= ((sh2->sr >> 4) & 0x0f))
  59                 return;
  60
  61         sh2_do_irq(sh2, level, 64 + level/2);
  62 }
  63
  64 void sh2_internal_irq(SH2 *sh2, int level, int vector)
  65 {
  66         sh2->pending_int_irq = level;
  67         sh2->pending_int_vector = vector;
  68         if (level <= ((sh2->sr >> 4) & 0x0f))
  69                 return;
  70
  71         sh2_do_irq(sh2, level, vector);
  72         sh2->pending_int_irq = 0; // auto-clear
  73 }
  74