SH4: system emulator interrupt update, by Magnus Damm.

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3762 c046a42c-6fe2-441c-8c8c-71466251a162

cpu-exec.c

@@ -511,7 +511,10 @@ int cpu_exec(CPUState *env1)
                         BREAK_CHAIN;
                     }
 #elif defined(TARGET_SH4)
-		    /* XXXXX */
+                    if (interrupt_request & CPU_INTERRUPT_HARD) {
+                        do_interrupt(env);
+                        BREAK_CHAIN;
+                    }
 #elif defined(TARGET_ALPHA)
                     if (interrupt_request & CPU_INTERRUPT_HARD) {
                         do_interrupt(env);

hw/sh7750.c

@@ -551,6 +551,8 @@ SH7750State *sh7750_init(CPUSH4State * cpu)
 			     _INTC_ARRAY(vectors),
 			     _INTC_ARRAY(groups));
 
+    cpu->intc_handle = &s->intc;
+
     sh_serial_init(0x1fe00000, 0, s->periph_freq, serial_hds[0]);
     sh_serial_init(0x1fe80000, SH_SERIAL_FEAT_SCIF,
 		   s->periph_freq, serial_hds[1]);

hw/sh_intc.c

@@ -14,10 +14,91 @@
 #include "sh.h"
 
 //#define DEBUG_INTC
+//#define DEBUG_INTC_SOURCES
 
 #define INTC_A7(x) ((x) & 0x1fffffff)
 #define INTC_ARRAY(x) (sizeof(x) / sizeof(x[0]))
 
+void sh_intc_toggle_source(struct intc_source *source,
+			   int enable_adj, int assert_adj)
+{
+    int enable_changed = 0;
+    int pending_changed = 0;
+    int old_pending;
+
+    if ((source->enable_count == source->enable_max) && (enable_adj == -1))
+        enable_changed = -1;
+
+    source->enable_count += enable_adj;
+
+    if (source->enable_count == source->enable_max)
+        enable_changed = 1;
+
+    source->asserted += assert_adj;
+
+    old_pending = source->pending;
+    source->pending = source->asserted &&
+      (source->enable_count == source->enable_max);
+
+    if (old_pending != source->pending)
+        pending_changed = 1;
+
+    if (pending_changed) {
+        if (source->pending) {
+            source->parent->pending++;
+	    if (source->parent->pending == 1)
+                cpu_interrupt(first_cpu, CPU_INTERRUPT_HARD);
+	}
+	else {
+            source->parent->pending--;
+	    if (source->parent->pending == 0)
+                cpu_reset_interrupt(first_cpu, CPU_INTERRUPT_HARD);
+	}
+    }
+
+  if (enable_changed || assert_adj || pending_changed) {
+#ifdef DEBUG_INTC_SOURCES
+            printf("sh_intc: (%d/%d/%d/%d) interrupt source 0x%x %s%s%s\n",
+		   source->parent->pending,
+		   source->asserted,
+		   source->enable_count,
+		   source->enable_max,
+		   source->vect,
+		   source->asserted ? "asserted " :
+		   assert_adj ? "deasserted" : "",
+		   enable_changed == 1 ? "enabled " :
+		   enable_changed == -1 ? "disabled " : "",
+		   source->pending ? "pending" : "");
+#endif
+  }
+}
+
+int sh_intc_get_pending_vector(struct intc_desc *desc, int imask)
+{
+    unsigned int i;
+
+    /* slow: use a linked lists of pending sources instead */
+    /* wrong: take interrupt priority into account (one list per priority) */
+
+    if (imask == 0x0f) {
+        return -1; /* FIXME, update code to include priority per source */
+    }
+
+    for (i = 0; i < desc->nr_sources; i++) {
+        struct intc_source *source = desc->sources + i;
+
+	if (source->pending) {
+#ifdef DEBUG_INTC_SOURCES
+            printf("sh_intc: (%d) returning interrupt source 0x%x\n",
+		   desc->pending, source->vect);
+#endif
+            return source->vect;
+	}
+    }
+
+    assert(0);
+}
+
 #define INTC_MODE_NONE       0
 #define INTC_MODE_DUAL_SET   1
 #define INTC_MODE_DUAL_CLR   2
@@ -94,42 +175,24 @@ static void sh_intc_locate(struct intc_desc *desc,
     assert(0);
 }
 
-static void sh_intc_toggle(struct intc_desc *desc, intc_enum id,
-			   int enable, int is_group)
+static void sh_intc_toggle_mask(struct intc_desc *desc, intc_enum id,
+				int enable, int is_group)
 {
     struct intc_source *source = desc->sources + id;
-    int old = source->enable_count;
 
     if (!id)
 	return;
 
     if (!source->next_enum_id && (!source->enable_max || !source->vect)) {
-#ifdef DEBUG_INTC
+#ifdef DEBUG_INTC_SOURCES
         printf("sh_intc: reserved interrupt source %d modified\n", id);
 #endif
 	return;
     }
 
-    if (source->vect) {
-        if (enable)
-            source->enable_count++;
-	else 
-            source->enable_count--;
+    if (source->vect)
+        sh_intc_toggle_source(source, enable ? 1 : -1, 0);
 
-        if (source->enable_count == source->enable_max) {
-#ifdef DEBUG_INTC
-            printf("sh_intc: enabling interrupt source %d -> 0x%04x\n",
-		   id, source->vect);
-#endif
-	}
-
-        if (old == source->enable_max) {
-#ifdef DEBUG_INTC
-            printf("sh_intc: disabling interrupt source %d -> 0x%04x\n",
-		   id, source->vect);
-#endif
-	}
-    }
 #ifdef DEBUG_INTC
     else {
         printf("setting interrupt group %d to %d\n", id, !!enable);
@@ -137,7 +200,7 @@ static void sh_intc_toggle(struct intc_desc *desc, intc_enum id,
 #endif
 
     if ((is_group || !source->vect) && source->next_enum_id) {
-        sh_intc_toggle(desc, source->next_enum_id, enable, 1);
+        sh_intc_toggle_mask(desc, source->next_enum_id, enable, 1);
     }
 
 #ifdef DEBUG_INTC
@@ -200,7 +263,7 @@ static void sh_intc_write(void *opaque, target_phys_addr_t offset,
 	printf("k = %d, first = %d, enum = %d, mask = 0x%08x\n", 
 	       k, first, enum_ids[k], (unsigned int)mask);
 #endif
-        sh_intc_toggle(desc, enum_ids[k], value & mask, 0);
+        sh_intc_toggle_mask(desc, enum_ids[k], value & mask, 0);
     }
 
     *valuep = value;
@@ -309,7 +372,7 @@ void sh_intc_register_sources(struct intc_desc *desc,
 	if (s)
 	    s->vect = vect->vect;
 
-#ifdef DEBUG_INTC
+#ifdef DEBUG_INTC_SOURCES
 	printf("sh_intc: registered source %d -> 0x%04x (%d/%d)\n",
 	       vect->enum_id, s->vect, s->enable_count, s->enable_max);
 #endif
@@ -330,7 +393,7 @@ void sh_intc_register_sources(struct intc_desc *desc,
 		s->next_enum_id = gr->enum_ids[k];
 	    }
 
-#ifdef DEBUG_INTC
+#ifdef DEBUG_INTC_SOURCES
 	    printf("sh_intc: registered group %d (%d/%d)\n",
 		   gr->enum_id, s->enable_count, s->enable_max);
 #endif
@@ -347,6 +410,7 @@ int sh_intc_init(struct intc_desc *desc,
 {
     unsigned int i;
 
+    desc->pending = 0;
     desc->nr_sources = nr_sources;
     desc->mask_regs = mask_regs;
     desc->nr_mask_regs = nr_mask_regs;
@@ -359,6 +423,11 @@ int sh_intc_init(struct intc_desc *desc,
         return -1;
 
     memset(desc->sources, 0, i);
+    for (i = 0; i < desc->nr_sources; i++) {
+        struct intc_source *source = desc->sources + i;
+
+        source->parent = desc;
+    }
  
     desc->iomemtype = cpu_register_io_memory(0, sh_intc_readfn,
 					     sh_intc_writefn, desc);

hw/sh_intc.h

@@ -35,9 +35,11 @@ struct intc_source {
     unsigned short vect;
     intc_enum next_enum_id;
 
-    int asserted;
+    int asserted; /* emulates the interrupt signal line from device to intc */
     int enable_count;
     int enable_max;
+    int pending; /* emulates the result of signal and masking */
+    struct intc_desc *parent;
 };
 
 struct intc_desc {
@@ -49,9 +51,13 @@ struct intc_desc {
     int nr_prio_regs;
 
     int iomemtype;
+    int pending; /* number of interrupt sources that has pending set */
 };
 
+int sh_intc_get_pending_vector(struct intc_desc *desc, int imask);
 struct intc_source *sh_intc_source(struct intc_desc *desc, intc_enum id);
+void sh_intc_toggle_source(struct intc_source *source,
+			   int enable_adj, int assert_adj);
 
 void sh_intc_register_sources(struct intc_desc *desc,
 			      struct intc_vect *vectors,

target-sh4/cpu.h

@@ -121,6 +121,7 @@ typedef struct CPUSH4State {
     int exception_index;
      CPU_COMMON tlb_t utlb[UTLB_SIZE];	/* unified translation table */
     tlb_t itlb[ITLB_SIZE];	/* instruction translation table */
+    void *intc_handle;
 } CPUSH4State;
 
 CPUSH4State *cpu_sh4_init(const char *cpu_model);

target-sh4/helper.c

@@ -27,6 +27,7 @@
 
 #include "cpu.h"
 #include "exec-all.h"
+#include "hw/sh_intc.h"
 
 #if defined(CONFIG_USER_ONLY)
 
@@ -74,6 +75,31 @@ target_phys_addr_t cpu_get_phys_page_debug(CPUState * env, target_ulong addr)
 
 void do_interrupt(CPUState * env)
 {
+    int do_irq = env->interrupt_request & CPU_INTERRUPT_HARD;
+    int do_exp, irq_vector = env->exception_index;
+
+    /* prioritize exceptions over interrupts */
+
+    do_exp = env->exception_index != -1;
+    do_irq = do_irq && (env->exception_index == -1);
+
+    if (env->sr & SR_BL) {
+        if (do_exp && env->exception_index != 0x1e0) {
+            env->exception_index = 0x000; /* masked exception -> reset */
+        }
+        if (do_irq) {
+            return; /* masked */
+        }
+    }
+
+    if (do_irq) {
+        irq_vector = sh_intc_get_pending_vector(env->intc_handle,
+						(env->sr >> 4) & 0xf);
+        if (irq_vector == -1) {
+            return; /* masked */
+	}
+    }
+
     if (loglevel & CPU_LOG_INT) {
 	const char *expname;
 	switch (env->exception_index) {
@@ -117,32 +143,47 @@ void do_interrupt(CPUState * env)
 	    expname = "trapa";
 	    break;
 	default:
-	    expname = "???";
-	    break;
+            expname = do_irq ? "interrupt" : "???";
+            break;
 	}
 	fprintf(logfile, "exception 0x%03x [%s] raised\n",
-		env->exception_index, expname);
+		irq_vector, expname);
 	cpu_dump_state(env, logfile, fprintf, 0);
     }
 
     env->ssr = env->sr;
-    env->spc = env->spc;
+    env->spc = env->pc;
     env->sgr = env->gregs[15];
     env->sr |= SR_BL | SR_MD | SR_RB;
 
-    env->expevt = env->exception_index & 0x7ff;
-    switch (env->exception_index) {
-    case 0x040:
-    case 0x060:
-    case 0x080:
-	env->pc = env->vbr + 0x400;
-	break;
-    case 0x140:
-	env->pc = 0xa0000000;
-	break;
-    default:
-	env->pc = env->vbr + 0x100;
-	break;
+    if (do_exp) {
+        env->expevt = env->exception_index;
+        switch (env->exception_index) {
+        case 0x000:
+        case 0x020:
+        case 0x140:
+            env->sr &= ~SR_FD;
+            env->sr |= 0xf << 4; /* IMASK */
+            env->pc = 0xa0000000;
+            break;
+        case 0x040:
+        case 0x060:
+            env->pc = env->vbr + 0x400;
+            break;
+        case 0x160:
+            env->spc += 2; /* special case for TRAPA */
+            /* fall through */
+        default:
+            env->pc = env->vbr + 0x100;
+            break;
+        }
+        return;
+    }
+
+    if (do_irq) {
+        env->intevt = irq_vector;
+        env->pc = env->vbr + 0x600;
+        return;
     }
 }
 

target-sh4/op.c

@@ -419,7 +419,7 @@ void OPPROTO op_subv_T0_T1(void)
 
 void OPPROTO op_trapa(void)
 {
-    env->tra = PARAM1 * 2;
+    env->tra = PARAM1 << 2;
     env->exception_index = 0x160;
     do_raise_exception();
     RETURN();