diff options
Diffstat (limited to 'src/hw/m68k/mcf_intc.c')
| -rw-r--r-- | src/hw/m68k/mcf_intc.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/src/hw/m68k/mcf_intc.c b/src/hw/m68k/mcf_intc.c new file mode 100644 index 0000000..f13c7f3 --- /dev/null +++ b/src/hw/m68k/mcf_intc.c @@ -0,0 +1,168 @@ +/* + * ColdFire Interrupt Controller emulation. + * + * Copyright (c) 2007 CodeSourcery. + * + * This code is licensed under the GPL + */ +#include "hw/hw.h" +#include "hw/m68k/mcf.h" +#include "exec/address-spaces.h" + +typedef struct { + MemoryRegion iomem; + uint64_t ipr; + uint64_t imr; + uint64_t ifr; + uint64_t enabled; + uint8_t icr[64]; + M68kCPU *cpu; + int active_vector; +} mcf_intc_state; + +static void mcf_intc_update(mcf_intc_state *s) +{ + uint64_t active; + int i; + int best; + int best_level; + + active = (s->ipr | s->ifr) & s->enabled & ~s->imr; + best_level = 0; + best = 64; + if (active) { + for (i = 0; i < 64; i++) { + if ((active & 1) != 0 && s->icr[i] >= best_level) { + best_level = s->icr[i]; + best = i; + } + active >>= 1; + } + } + s->active_vector = ((best == 64) ? 24 : (best + 64)); + m68k_set_irq_level(s->cpu, best_level, s->active_vector); +} + +static uint64_t mcf_intc_read(void *opaque, hwaddr addr, + unsigned size) +{ + int offset; + mcf_intc_state *s = (mcf_intc_state *)opaque; + offset = addr & 0xff; + if (offset >= 0x40 && offset < 0x80) { + return s->icr[offset - 0x40]; + } + switch (offset) { + case 0x00: + return (uint32_t)(s->ipr >> 32); + case 0x04: + return (uint32_t)s->ipr; + case 0x08: + return (uint32_t)(s->imr >> 32); + case 0x0c: + return (uint32_t)s->imr; + case 0x10: + return (uint32_t)(s->ifr >> 32); + case 0x14: + return (uint32_t)s->ifr; + case 0xe0: /* SWIACK. */ + return s->active_vector; + case 0xe1: case 0xe2: case 0xe3: case 0xe4: + case 0xe5: case 0xe6: case 0xe7: + /* LnIACK */ + hw_error("mcf_intc_read: LnIACK not implemented\n"); + default: + return 0; + } +} + +static void mcf_intc_write(void *opaque, hwaddr addr, + uint64_t val, unsigned size) +{ + int offset; + mcf_intc_state *s = (mcf_intc_state *)opaque; + offset = addr & 0xff; + if (offset >= 0x40 && offset < 0x80) { + int n = offset - 0x40; + s->icr[n] = val; + if (val == 0) + s->enabled &= ~(1ull << n); + else + s->enabled |= (1ull << n); + mcf_intc_update(s); + return; + } + switch (offset) { + case 0x00: case 0x04: + /* Ignore IPR writes. */ + return; + case 0x08: + s->imr = (s->imr & 0xffffffff) | ((uint64_t)val << 32); + break; + case 0x0c: + s->imr = (s->imr & 0xffffffff00000000ull) | (uint32_t)val; + break; + case 0x1c: + if (val & 0x40) { + s->imr = ~0ull; + } else { + s->imr |= (0x1ull << (val & 0x3f)); + } + break; + case 0x1d: + if (val & 0x40) { + s->imr = 0ull; + } else { + s->imr &= ~(0x1ull << (val & 0x3f)); + } + break; + default: + hw_error("mcf_intc_write: Bad write offset %d\n", offset); + break; + } + mcf_intc_update(s); +} + +static void mcf_intc_set_irq(void *opaque, int irq, int level) +{ + mcf_intc_state *s = (mcf_intc_state *)opaque; + if (irq >= 64) + return; + if (level) + s->ipr |= 1ull << irq; + else + s->ipr &= ~(1ull << irq); + mcf_intc_update(s); +} + +static void mcf_intc_reset(mcf_intc_state *s) +{ + s->imr = ~0ull; + s->ipr = 0; + s->ifr = 0; + s->enabled = 0; + memset(s->icr, 0, 64); + s->active_vector = 24; +} + +static const MemoryRegionOps mcf_intc_ops = { + .read = mcf_intc_read, + .write = mcf_intc_write, + .endianness = DEVICE_NATIVE_ENDIAN, +}; + +qemu_irq *mcf_intc_init(MemoryRegion *sysmem, + hwaddr base, + M68kCPU *cpu) +{ + mcf_intc_state *s; + + s = g_malloc0(sizeof(mcf_intc_state)); + s->cpu = cpu; + mcf_intc_reset(s); + + memory_region_init_io(&s->iomem, NULL, &mcf_intc_ops, s, "mcf", 0x100); + memory_region_add_subregion(sysmem, base, &s->iomem); + + return qemu_allocate_irqs(mcf_intc_set_irq, s, 64); +} |
