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Diffstat (limited to 'qemu/hw/m68k/mcf_intc.c')
-rw-r--r--qemu/hw/m68k/mcf_intc.c168
1 files changed, 168 insertions, 0 deletions
diff --git a/qemu/hw/m68k/mcf_intc.c b/qemu/hw/m68k/mcf_intc.c
new file mode 100644
index 000000000..f13c7f3ae
--- /dev/null
+++ b/qemu/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);
+}