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Slight PIC interrupt processing rework.

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This commit is contained in:
OBattler
2017-08-28 04:24:33 +02:00
parent 90d7b71e5e
commit ef29b928ea
1 changed files with 66 additions and 76 deletions
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142
src/pic.c
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@@ -378,92 +378,82 @@ void picintc(uint16_t num)
pic_updatepending();
}
static uint8_t pic_process_interrupt(PIC* target_pic, int c)
{
uint8_t pending = target_pic->pend & ~target_pic->mask;
int pic_int = c & 7;
int pic_int_num = 1 << pic_int;
int pic_cur_num = 1 << c;
if (pending & pic_int_num)
{
if (!(pic_current & pic_cur_num))
{
target_pic->pend &= ~pic_int_num;
}
target_pic->ins |= pic_int_num;
pic_update_mask(&target_pic->mask2, target_pic->ins);
if (c >= 8)
{
pic.ins |= (1 << 2); /*Cascade IRQ*/
pic_update_mask(&pic.mask2, pic.ins);
}
pic_updatepending();
if (target_pic->icw4 & 0x02)
{
(c >= 8) ? pic2_autoeoi() : pic_autoeoi();
}
if (!c)
{
pit_set_gate(&pit2, 0, 0);
}
return pic_int + target_pic->vector;
}
else
{
return 0xFF;
}
}
uint8_t picinterrupt()
{
uint8_t temp=pic.pend&~pic.mask;
int c;
for (c = 0; c < 2; c++)
uint8_t ret;
uint8_t irq2_pending = (pic.pend & ~pic.mask) & (1 << 2);
for (c = 0; c <= 1; c++)
{
if (temp & (1 << c))
{
if (!(pic_current & (1 << c)))
{
pic.pend &= ~(1 << c);
pic.ins |= (1 << c);
pic_update_mask(&pic.mask2, pic.ins);
pic_updatepending();
if (!c)
pit_set_gate(&pit2, 0, 0);
if (pic.icw4 & 0x02)
pic_autoeoi();
}
return c+pic.vector;
}
ret = pic_process_interrupt(&pic, c);
if (ret != 0xFF) return ret;
}
if ((temp & (1 << 2)) && !AT)
if (irq2_pending)
{
if (temp & (1 << 2))
if (AT)
{
for (c = 8; c <= 15; c++)
{
ret = pic_process_interrupt(&pic2, c);
if (ret != 0xFF) return ret;
}
}
else
{
if (!(pic_current & (1 << 2)))
{
pic.pend &= ~(1 << 2);
pic.ins |= (1 << 2);
pic_update_mask(&pic.mask2, pic.ins);
pic_updatepending();
if (pic.icw4 & 0x02)
pic_autoeoi();
}
return c+pic.vector;
ret = pic_process_interrupt(&pic, 2);
if (ret != 0xFF) return ret;
}
}
if ((temp & (1 << 2)) && AT)
for (c = 3; c <= 7; c++)
{
uint8_t temp2 = pic2.pend & ~pic2.mask;
for (c = 0; c < 8; c++)
{
if (temp2 & (1 << c))
{
if (!(pic_current & (256 << c)))
{
pic2.pend &= ~(1 << c);
pic2.ins |= (1 << c);
pic_update_mask(&pic2.mask2, pic2.ins);
pic.ins |= (1 << 2); /*Cascade IRQ*/
pic_update_mask(&pic.mask2, pic.ins);
pic_updatepending();
if (pic2.icw4 & 0x02)
pic2_autoeoi();
}
return c+pic2.vector;
}
}
}
for (c = 3; c < 8; c++)
{
if (temp & (1 << c))
{
if (!(pic_current & (1 << c)))
{
pic.pend &= ~(1 << c);
pic.ins |= (1 << c);
pic_update_mask(&pic.mask2, pic.ins);
pic_updatepending();
if (pic.icw4 & 0x02)
pic_autoeoi();
}
return c+pic.vector;
}
ret = pic_process_interrupt(&pic, c);
if (ret != 0xFF) return ret;
}
return 0xFF;
}