target-alpha: Disable interrupts properly.

Interrupts are disabled in PALmode, and when the PS IL is high enough.

Signed-off-by: Richard Henderson <rth@twiddle.net>

cpu-exec.c

@@ -488,9 +488,36 @@ int cpu_exec(CPUState *env1)
                         next_tb = 0;
                     }
 #elif defined(TARGET_ALPHA)
-                    if (interrupt_request & CPU_INTERRUPT_HARD) {
-                        do_interrupt(env);
-                        next_tb = 0;
+                    {
+                        int idx = -1;
+                        /* ??? This hard-codes the OSF/1 interrupt levels.  */
+		        switch (env->pal_mode ? 7 : env->ps & PS_INT_MASK) {
+                        case 0 ... 3:
+                            if (interrupt_request & CPU_INTERRUPT_HARD) {
+                                idx = EXCP_DEV_INTERRUPT;
+                            }
+                            /* FALLTHRU */
+                        case 4:
+                            if (interrupt_request & CPU_INTERRUPT_TIMER) {
+                                idx = EXCP_CLK_INTERRUPT;
+                            }
+                            /* FALLTHRU */
+                        case 5:
+                            if (interrupt_request & CPU_INTERRUPT_SMP) {
+                                idx = EXCP_SMP_INTERRUPT;
+                            }
+                            /* FALLTHRU */
+                        case 6:
+                            if (interrupt_request & CPU_INTERRUPT_MCHK) {
+                                idx = EXCP_MCHK;
+                            }
+                        }
+                        if (idx >= 0) {
+                            env->exception_index = idx;
+                            env->error_code = 0;
+                            do_interrupt(env);
+                            next_tb = 0;
+                        }
                     }
 #elif defined(TARGET_CRIS)
                     if (interrupt_request & CPU_INTERRUPT_HARD

target-alpha/cpu.h

@@ -315,6 +315,11 @@ enum {
     EXCP_STQ_C,
 };
 
+/* Alpha-specific interrupt pending bits.  */
+#define CPU_INTERRUPT_TIMER	CPU_INTERRUPT_TGT_EXT_0
+#define CPU_INTERRUPT_SMP	CPU_INTERRUPT_TGT_EXT_1
+#define CPU_INTERRUPT_MCHK	CPU_INTERRUPT_TGT_EXT_2
+
 /* Hardware interrupt (entInt) constants.  */
 enum {
     INT_K_IP,

target-alpha/exec.h

@@ -39,7 +39,17 @@ register struct CPUAlphaState *env asm(AREG0);
 
 static inline int cpu_has_work(CPUState *env)
 {
-    return (env->interrupt_request & CPU_INTERRUPT_HARD);
+    /* Here we are checking to see if the CPU should wake up from HALT.
+       We will have gotten into this state only for WTINT from PALmode.  */
+    /* ??? I'm not sure how the IPL state works with WTINT to keep a CPU
+       asleep even if (some) interrupts have been asserted.  For now, 
+       assume that if a CPU really wants to stay asleep, it will mask
+       interrupts at the chipset level, which will prevent these bits
+       from being set in the first place.  */
+    return env->interrupt_request & (CPU_INTERRUPT_HARD
+                                     | CPU_INTERRUPT_TIMER
+                                     | CPU_INTERRUPT_SMP
+                                     | CPU_INTERRUPT_MCHK);
 }
 
 static inline void cpu_pc_from_tb(CPUState *env, TranslationBlock *tb)