Sparc32: improve interrupt handling

Level 15 interrupts are broadcast to all CPUs, each CPU can clear the
interrupt using the local Clear Pending register.

Update intbit_to_level table.

Don't try to raise level 0 interrupts.

Calculate pending interrupts based on the separate inputs from master
register. Setting or resetting the pending level isn't correct because of
overlap of levels.

Level 14 is always used for CPU timer interrupts, remove the property.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>

2 files changed, 47 insertions, 32 deletions

diff --git a/hw/slavio_intctl.c b/hw/slavio_intctl.c
index 7ac1c93..6961cb0 100644
--- a/hw/slavio_intctl.c
+++ b/hw/slavio_intctl.c
@@ -56,6 +56,7 @@ typedef struct SLAVIO_CPUINTCTLState {
     uint32_t intreg_pending;
     struct SLAVIO_INTCTLState *master;
     uint32_t cpu;
+    uint32_t irl_out;
 } SLAVIO_CPUINTCTLState;
 
 typedef struct SLAVIO_INTCTLState {
@@ -67,9 +68,6 @@ typedef struct SLAVIO_INTCTLState {
     uint64_t irq_count[32];
 #endif
     qemu_irq cpu_irqs[MAX_CPUS][MAX_PILS];
-    uint32_t cputimer_lbit, cputimer_mbit;
-    uint32_t cputimer_bit;
-    uint32_t pil_out[MAX_CPUS];
     SLAVIO_CPUINTCTLState slaves[MAX_CPUS];
 } SLAVIO_INTCTLState;
 
@@ -79,8 +77,8 @@ typedef struct SLAVIO_INTCTLState {
 #define MASTER_IRQ_MASK ~0x0fa2007f
 #define MASTER_DISABLE 0x80000000
 #define CPU_SOFTIRQ_MASK 0xfffe0000
-#define CPU_IRQ_INT15_IN 0x0004000
-#define CPU_IRQ_INT15_MASK 0x80000000
+#define CPU_IRQ_INT15_IN (1 << 15)
+#define CPU_IRQ_TIMER_IN (1 << 14)
 
 static void slavio_check_interrupts(SLAVIO_INTCTLState *s, int set_irqs);
 
@@ -114,9 +112,7 @@ static void slavio_intctl_mem_writel(void *opaque, target_phys_addr_t addr,
     DPRINTF("write cpu %d reg 0x" TARGET_FMT_plx " = %x\n", s->cpu, addr, val);
     switch (saddr) {
     case 1: // clear pending softints
-        if (val & CPU_IRQ_INT15_IN)
-            val |= CPU_IRQ_INT15_MASK;
-        val &= CPU_SOFTIRQ_MASK;
+        val &= CPU_SOFTIRQ_MASK | CPU_IRQ_INT15_IN;
         s->intreg_pending &= ~val;
         slavio_check_interrupts(s->master, 1);
         DPRINTF("Cleared cpu %d irq mask %x, curmask %x\n", s->cpu, val,
@@ -258,8 +254,8 @@ void slavio_irq_info(Monitor *mon, DeviceState *dev)
 }
 
 static const uint32_t intbit_to_level[] = {
-    2, 3, 5, 7, 9, 11, 0, 14,   3, 5, 7, 9, 11, 13, 12, 12,
-    6, 0, 4, 10, 8, 0, 11, 0,   0, 0, 0, 0, 15, 0, 15, 0,
+    2, 3, 5, 7, 9, 11, 13, 2,   3, 5, 7, 9, 11, 13, 12, 12,
+    6, 13, 4, 10, 8, 9, 11, 0,  0, 0, 0, 15, 15, 15, 15, 0,
 };
 
 static void slavio_check_interrupts(SLAVIO_INTCTLState *s, int set_irqs)
@@ -272,29 +268,49 @@ static void slavio_check_interrupts(SLAVIO_INTCTLState *s, int set_irqs)
     DPRINTF("pending %x disabled %x\n", pending, s->intregm_disabled);
     for (i = 0; i < MAX_CPUS; i++) {
         pil_pending = 0;
+
+        /* If we are the current interrupt target, get hard interrupts */
         if (pending && !(s->intregm_disabled & MASTER_DISABLE) &&
             (i == s->target_cpu)) {
             for (j = 0; j < 32; j++) {
-                if (pending & (1 << j))
+                if ((pending & (1 << j)) && intbit_to_level[j]) {
                     pil_pending |= 1 << intbit_to_level[j];
+                }
+            }
+        }
+
+        /* Calculate current pending hard interrupts for display */
+        s->slaves[i].intreg_pending &= CPU_SOFTIRQ_MASK | CPU_IRQ_INT15_IN |
+            CPU_IRQ_TIMER_IN;
+        if (i == s->target_cpu) {
+            for (j = 0; j < 32; j++) {
+                if ((s->intregm_pending & (1 << j)) && intbit_to_level[j]) {
+                    s->slaves[i].intreg_pending |= 1 << intbit_to_level[j];
+                }
             }
         }
+
+        /* Level 15 and CPU timer interrupts are not maskable */
+        pil_pending |= s->slaves[i].intreg_pending &
+            (CPU_IRQ_INT15_IN | CPU_IRQ_TIMER_IN);
+
+        /* Add soft interrupts */
         pil_pending |= (s->slaves[i].intreg_pending & CPU_SOFTIRQ_MASK) >> 16;
 
         if (set_irqs) {
-            for (j = 0; j < MAX_PILS; j++) {
+            for (j = MAX_PILS; j > 0; j--) {
                 if (pil_pending & (1 << j)) {
-                    if (!(s->pil_out[i] & (1 << j))) {
+                    if (!(s->slaves[i].irl_out & (1 << j))) {
                         qemu_irq_raise(s->cpu_irqs[i][j]);
                     }
                 } else {
-                    if (s->pil_out[i] & (1 << j)) {
+                    if (s->slaves[i].irl_out & (1 << j)) {
                         qemu_irq_lower(s->cpu_irqs[i][j]);
                     }
                 }
             }
         }
-        s->pil_out[i] = pil_pending;
+        s->slaves[i].irl_out = pil_pending;
     }
 }
 
@@ -307,6 +323,7 @@ static void slavio_set_irq(void *opaque, int irq, int level)
     SLAVIO_INTCTLState *s = opaque;
     uint32_t mask = 1 << irq;
     uint32_t pil = intbit_to_level[irq];
+    unsigned int i;
 
     DPRINTF("Set cpu %d irq %d -> pil %d level %d\n", s->target_cpu, irq, pil,
             level);
@@ -316,10 +333,18 @@ static void slavio_set_irq(void *opaque, int irq, int level)
             s->irq_count[pil]++;
 #endif
             s->intregm_pending |= mask;
-            s->slaves[s->target_cpu].intreg_pending |= 1 << pil;
+            if (pil == 15) {
+                for (i = 0; i < MAX_CPUS; i++) {
+                    s->slaves[i].intreg_pending |= 1 << pil;
+                }
+            }
         } else {
             s->intregm_pending &= ~mask;
-            s->slaves[s->target_cpu].intreg_pending &= ~(1 << pil);
+            if (pil == 15) {
+                for (i = 0; i < MAX_CPUS; i++) {
+                    s->slaves[i].intreg_pending &= ~(1 << pil);
+                }
+            }
         }
         slavio_check_interrupts(s, 1);
     }
@@ -332,11 +357,9 @@ static void slavio_set_timer_irq_cpu(void *opaque, int cpu, int level)
     DPRINTF("Set cpu %d local timer level %d\n", cpu, level);
 
     if (level) {
-        s->intregm_pending |= s->cputimer_mbit;
-        s->slaves[cpu].intreg_pending |= s->cputimer_lbit;
+        s->slaves[cpu].intreg_pending |= CPU_IRQ_TIMER_IN;
     } else {
-        s->intregm_pending &= ~s->cputimer_mbit;
-        s->slaves[cpu].intreg_pending &= ~s->cputimer_lbit;
+        s->slaves[cpu].intreg_pending &= ~CPU_IRQ_TIMER_IN;
     }
 
     slavio_check_interrupts(s, 1);
@@ -389,6 +412,7 @@ static void slavio_intctl_reset(void *opaque)
 
     for (i = 0; i < MAX_CPUS; i++) {
         s->slaves[i].intreg_pending = 0;
+        s->slaves[i].irl_out = 0;
     }
     s->intregm_disabled = ~MASTER_IRQ_MASK;
     s->intregm_pending = 0;
@@ -406,8 +430,6 @@ static void slavio_intctl_init1(SysBusDevice *dev)
     io_memory = cpu_register_io_memory(slavio_intctlm_mem_read,
                                        slavio_intctlm_mem_write, s);
     sysbus_init_mmio(dev, INTCTLM_SIZE, io_memory);
-    s->cputimer_mbit = 1 << s->cputimer_bit;
-    s->cputimer_lbit = 1 << intbit_to_level[s->cputimer_bit];
 
     for (i = 0; i < MAX_CPUS; i++) {
         for (j = 0; j < MAX_PILS; j++) {
@@ -430,10 +452,6 @@ static SysBusDeviceInfo slavio_intctl_info = {
     .init = slavio_intctl_init1,
     .qdev.name  = "slavio_intctl",
     .qdev.size  = sizeof(SLAVIO_INTCTLState),
-    .qdev.props = (Property[]) {
-        DEFINE_PROP_UINT32("cputimer_bit", SLAVIO_INTCTLState, cputimer_bit, 0),
-        DEFINE_PROP_END_OF_LIST(),
-    }
 };
 
 static void slavio_intctl_register_devices(void)
diff --git a/hw/sun4m.c b/hw/sun4m.c
index 88a0b25..17854db 100644
--- a/hw/sun4m.c
+++ b/hw/sun4m.c
@@ -396,15 +396,13 @@ static void lance_init(NICInfo *nd, target_phys_addr_t leaddr,
 
 static DeviceState *slavio_intctl_init(target_phys_addr_t addr,
                                        target_phys_addr_t addrg,
-                                       qemu_irq **parent_irq,
-                                       unsigned int cputimer)
+                                       qemu_irq **parent_irq)
 {
     DeviceState *dev;
     SysBusDevice *s;
     unsigned int i, j;
 
     dev = qdev_create(NULL, "slavio_intctl");
-    qdev_prop_set_uint32(dev, "cputimer_bit", cputimer);
     qdev_init(dev);
 
     s = sysbus_from_qdev(dev);
@@ -769,8 +767,7 @@ static void sun4m_hw_init(const struct sun4m_hwdef *hwdef, ram_addr_t RAM_size,
 
     slavio_intctl = slavio_intctl_init(hwdef->intctl_base,
                                        hwdef->intctl_base + 0x10000ULL,
-                                       cpu_irqs,
-                                       7);
+                                       cpu_irqs);
 
     for (i = 0; i < 32; i++) {
         slavio_irq[i] = qdev_get_gpio_in(slavio_intctl, i);