155 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			155 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			C
		
	
	
	
| /*
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|  * ColdFire Interrupt Controller emulation.
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|  *
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|  * Copyright (c) 2007 CodeSourcery.
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|  *
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|  * This code is licensed under the GPL
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|  */
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| #include "hw/hw.h"
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| #include "hw/m68k/mcf.h"
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| #include "exec/address-spaces.h"
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| 
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| typedef struct {
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|     MemoryRegion iomem;
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|     uint64_t ipr;
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|     uint64_t imr;
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|     uint64_t ifr;
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|     uint64_t enabled;
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|     uint8_t icr[64];
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|     M68kCPU *cpu;
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|     int active_vector;
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| } mcf_intc_state;
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| 
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| static void mcf_intc_update(mcf_intc_state *s)
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| {
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|     uint64_t active;
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|     int i;
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|     int best;
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|     int best_level;
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| 
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|     active = (s->ipr | s->ifr) & s->enabled & ~s->imr;
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|     best_level = 0;
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|     best = 64;
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|     if (active) {
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|         for (i = 0; i < 64; i++) {
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|             if ((active & 1) != 0 && s->icr[i] >= best_level) {
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|                 best_level = s->icr[i];
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|                 best = i;
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|             }
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|             active >>= 1;
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|         }
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|     }
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|     s->active_vector = ((best == 64) ? 24 : (best + 64));
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|     m68k_set_irq_level(s->cpu, best_level, s->active_vector);
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| }
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| 
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| static uint64_t mcf_intc_read(void *opaque, hwaddr addr,
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|                               unsigned size)
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| {
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|     int offset;
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|     mcf_intc_state *s = (mcf_intc_state *)opaque;
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|     offset = addr & 0xff;
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|     if (offset >= 0x40 && offset < 0x80) {
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|         return s->icr[offset - 0x40];
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|     }
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|     switch (offset) {
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|     case 0x00:
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|         return (uint32_t)(s->ipr >> 32);
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|     case 0x04:
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|         return (uint32_t)s->ipr;
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|     case 0x08:
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|         return (uint32_t)(s->imr >> 32);
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|     case 0x0c:
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|         return (uint32_t)s->imr;
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|     case 0x10:
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|         return (uint32_t)(s->ifr >> 32);
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|     case 0x14:
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|         return (uint32_t)s->ifr;
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|     case 0xe0: /* SWIACK.  */
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|         return s->active_vector;
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|     case 0xe1: case 0xe2: case 0xe3: case 0xe4:
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|     case 0xe5: case 0xe6: case 0xe7:
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|         /* LnIACK */
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|         hw_error("mcf_intc_read: LnIACK not implemented\n");
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|     default:
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|         return 0;
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|     }
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| }
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| 
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| static void mcf_intc_write(void *opaque, hwaddr addr,
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|                            uint64_t val, unsigned size)
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| {
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|     int offset;
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|     mcf_intc_state *s = (mcf_intc_state *)opaque;
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|     offset = addr & 0xff;
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|     if (offset >= 0x40 && offset < 0x80) {
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|         int n = offset - 0x40;
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|         s->icr[n] = val;
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|         if (val == 0)
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|             s->enabled &= ~(1ull << n);
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|         else
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|             s->enabled |= (1ull << n);
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|         mcf_intc_update(s);
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|         return;
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|     }
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|     switch (offset) {
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|     case 0x00: case 0x04:
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|         /* Ignore IPR writes.  */
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|         return;
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|     case 0x08:
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|         s->imr = (s->imr & 0xffffffff) | ((uint64_t)val << 32);
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|         break;
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|     case 0x0c:
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|         s->imr = (s->imr & 0xffffffff00000000ull) | (uint32_t)val;
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|         break;
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|     default:
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|         hw_error("mcf_intc_write: Bad write offset %d\n", offset);
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|         break;
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|     }
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|     mcf_intc_update(s);
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| }
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| 
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| static void mcf_intc_set_irq(void *opaque, int irq, int level)
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| {
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|     mcf_intc_state *s = (mcf_intc_state *)opaque;
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|     if (irq >= 64)
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|         return;
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|     if (level)
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|         s->ipr |= 1ull << irq;
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|     else
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|         s->ipr &= ~(1ull << irq);
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|     mcf_intc_update(s);
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| }
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| 
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| static void mcf_intc_reset(mcf_intc_state *s)
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| {
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|     s->imr = ~0ull;
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|     s->ipr = 0;
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|     s->ifr = 0;
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|     s->enabled = 0;
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|     memset(s->icr, 0, 64);
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|     s->active_vector = 24;
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| }
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| 
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| static const MemoryRegionOps mcf_intc_ops = {
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|     .read = mcf_intc_read,
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|     .write = mcf_intc_write,
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|     .endianness = DEVICE_NATIVE_ENDIAN,
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| };
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| 
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| qemu_irq *mcf_intc_init(MemoryRegion *sysmem,
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|                         hwaddr base,
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|                         M68kCPU *cpu)
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| {
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|     mcf_intc_state *s;
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| 
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|     s = g_malloc0(sizeof(mcf_intc_state));
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|     s->cpu = cpu;
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|     mcf_intc_reset(s);
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| 
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|     memory_region_init_io(&s->iomem, NULL, &mcf_intc_ops, s, "mcf", 0x100);
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|     memory_region_add_subregion(sysmem, base, &s->iomem);
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| 
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|     return qemu_allocate_irqs(mcf_intc_set_irq, s, 64);
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| }
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