m68k: MOVEC insn. should generate exception if wrong CR is accessed

Add CPU class detection for each CR type in the m68k_move_to/from helpers,
so that it throws and exception if an unsupported register is requested
for that CPU class.

Reclassified MOVEC insn. as only supported from 68010.

Backports 8df0e6aedad33c6746f4bc2a4d0cfdd432877084

qemu/target/m68k/cpu.c

@@ -111,6 +111,20 @@ static void m68000_cpu_initfn(struct uc_struct *uc, Object *obj, void *opaque)
     m68k_set_feature(env, M68K_FEATURE_MOVEP);
 }
 
+/*
+ * Adds BKPT, MOVE-from-SR *now priv instr, and MOVEC, MOVES, RTD
+ */
+static void m68010_cpu_initfn(struct uc_struct *uc, Object *obj, void *opaque)
+{
+    M68kCPU *cpu = M68K_CPU(uc, obj);
+    CPUM68KState *env = &cpu->env;
+    m68000_cpu_initfn(uc, obj, opaque);
+    m68k_set_feature(env, M68K_FEATURE_M68010);
+    m68k_set_feature(env, M68K_FEATURE_RTD);
+    m68k_set_feature(env, M68K_FEATURE_BKPT);
+    m68k_set_feature(env, M68K_FEATURE_MOVEC);
+}
+
 /* common features for 68020, 68030 and 68040 */
 static void m680x0_cpu_common(CPUM68KState *env)
 {
@@ -342,6 +356,7 @@ static TypeInfo m68k_cpus_type_infos[] = {
         .abstract = true,
     },
     DEFINE_M68K_CPU_TYPE("m68000", m68000_cpu_initfn),
+    DEFINE_M68K_CPU_TYPE("m68010", m68010_cpu_initfn),
     DEFINE_M68K_CPU_TYPE("m68020", m68020_cpu_initfn),
     DEFINE_M68K_CPU_TYPE("m68030", m68030_cpu_initfn),
     DEFINE_M68K_CPU_TYPE("m68040", m68040_cpu_initfn),

qemu/target/m68k/cpu.h

@@ -466,6 +466,7 @@ void do_m68k_semihosting(CPUM68KState *env, int nr);
 enum m68k_features {
     /* Base m68k instruction set */
     M68K_FEATURE_M68000,
+    M68K_FEATURE_M68010,
     M68K_FEATURE_M68020,
     M68K_FEATURE_M68030,
     M68K_FEATURE_M68040,

qemu/target/m68k/helper.c

@@ -29,6 +29,14 @@
 
 void raise_exception(CPUM68KState *env, int tt);
 
+static void raise_exception_ra(CPUM68KState *env, int tt, uintptr_t raddr)
+{
+    CPUState *cs = env_cpu(env);
+
+    cs->exception_index = tt;
+    cpu_loop_exit_restore(cs, raddr);
+}
+
 void HELPER(cf_movec_to)(CPUM68KState *env, uint32_t reg, uint32_t val)
 {
     switch (reg) {
@@ -78,63 +86,106 @@ void HELPER(m68k_movec_to)(CPUM68KState *env, uint32_t reg, uint32_t val)
             env->cacr = val & 0x80008000;
         } else if (m68k_feature(env, M68K_FEATURE_M68060)) {
             env->cacr = val & 0xf8e0e000;
+        } else {
+            break;
         }
         m68k_switch_sp(env);
         return;
     /* MC680[46]0 */
     case M68K_CR_TC:
+        if (m68k_feature(env, M68K_FEATURE_M68040)
+         || m68k_feature(env, M68K_FEATURE_M68060)) {
             env->mmu.tcr = val;
             return;
+        }
+        break;
     /* MC68040 */
     case M68K_CR_MMUSR:
+        if (m68k_feature(env, M68K_FEATURE_M68040)) {
             env->mmu.mmusr = val;
             return;
+        }
+        break;
     /* MC680[46]0 */
     case M68K_CR_SRP:
+        if (m68k_feature(env, M68K_FEATURE_M68040)
+         || m68k_feature(env, M68K_FEATURE_M68060)) {
             env->mmu.srp = val;
             return;
+        }
+        break;
+    /* MC680[46]0 */
     case M68K_CR_URP:
+        if (m68k_feature(env, M68K_FEATURE_M68040)
+         || m68k_feature(env, M68K_FEATURE_M68060)) {
             env->mmu.urp = val;
             return;
-    /* MC680[46]0 */
+        }
+        break;
+    /* MC680[12346]0 */
     case M68K_CR_USP:
         env->sp[M68K_USP] = val;
         return;
     /* MC680[234]0 */
     case M68K_CR_MSP:
+        if (m68k_feature(env, M68K_FEATURE_M68020)
+         || m68k_feature(env, M68K_FEATURE_M68030)
+         || m68k_feature(env, M68K_FEATURE_M68040)) {
             env->sp[M68K_SSP] = val;
             return;
+        }
+        break;
     /* MC680[234]0 */
     case M68K_CR_ISP:
+        if (m68k_feature(env, M68K_FEATURE_M68020)
+         || m68k_feature(env, M68K_FEATURE_M68030)
+         || m68k_feature(env, M68K_FEATURE_M68040)) {
             env->sp[M68K_ISP] = val;
             return;
+        }
+        break;
     /* MC68040/MC68LC040 */
-    case M68K_CR_ITT0:
+    case M68K_CR_ITT0: /* MC68EC040 only: M68K_CR_IACR0 */
+        if (m68k_feature(env, M68K_FEATURE_M68040)) {
             env->mmu.ttr[M68K_ITTR0] = val;
             return;
+        }
+        break;
     /* MC68040/MC68LC040 */
-    case M68K_CR_ITT1:
+    case M68K_CR_ITT1: /* MC68EC040 only: M68K_CR_IACR1 */
+        if (m68k_feature(env, M68K_FEATURE_M68040)) {
             env->mmu.ttr[M68K_ITTR1] = val;
             return;
+        }
+        break;
     /* MC68040/MC68LC040 */
-    case M68K_CR_DTT0:
+    case M68K_CR_DTT0: /* MC68EC040 only: M68K_CR_DACR0 */
+        if (m68k_feature(env, M68K_FEATURE_M68040)) {
             env->mmu.ttr[M68K_DTTR0] = val;
             return;
+        }
+        break;
     /* MC68040/MC68LC040 */
-    case M68K_CR_DTT1:
+    case M68K_CR_DTT1: /* MC68EC040 only: M68K_CR_DACR1 */
+        if (m68k_feature(env, M68K_FEATURE_M68040)) {
             env->mmu.ttr[M68K_DTTR1] = val;
             return;
+        }
+        break;
     /* Unimplemented Registers */
     case M68K_CR_CAAR:
     case M68K_CR_PCR:
     case M68K_CR_BUSCR:
-        break;
-    }
         cpu_abort(env_cpu(env),
                   "Unimplemented control register write 0x%x = 0x%x\n",
                   reg, val);
     }
 
+    /* Invalid control registers will generate an exception. */
+    raise_exception_ra(env, EXCP_ILLEGAL, 0);
+    return;
+}
+
 uint32_t HELPER(m68k_movec_from)(CPUM68KState *env, uint32_t reg)
 {
     switch (reg) {
@@ -149,50 +200,97 @@ uint32_t HELPER(m68k_movec_from)(CPUM68KState *env, uint32_t reg)
         return env->vbr;
     /* MC680[2346]0 */
     case M68K_CR_CACR:
+        if (m68k_feature(env, M68K_FEATURE_M68020)
+         || m68k_feature(env, M68K_FEATURE_M68030)
+         || m68k_feature(env, M68K_FEATURE_M68040)
+         || m68k_feature(env, M68K_FEATURE_M68060)) {
             return env->cacr;
+        }
+        break;
     /* MC680[46]0 */
     case M68K_CR_TC:
+        if (m68k_feature(env, M68K_FEATURE_M68040)
+         || m68k_feature(env, M68K_FEATURE_M68060)) {
             return env->mmu.tcr;
+        }
+        break;
     /* MC68040 */
     case M68K_CR_MMUSR:
+        if (m68k_feature(env, M68K_FEATURE_M68040)) {
             return env->mmu.mmusr;
+        }
+        break;
     /* MC680[46]0 */
     case M68K_CR_SRP:
+        if (m68k_feature(env, M68K_FEATURE_M68040)
+         || m68k_feature(env, M68K_FEATURE_M68060)) {
             return env->mmu.srp;
+        }
+        break;
+    /* MC68040/MC68LC040 */
+    case M68K_CR_URP:
+        if (m68k_feature(env, M68K_FEATURE_M68040)
+         || m68k_feature(env, M68K_FEATURE_M68060)) {
+            return env->mmu.urp;
+        }
+        break;
     /* MC680[46]0 */
     case M68K_CR_USP:
         return env->sp[M68K_USP];
     /* MC680[234]0 */
     case M68K_CR_MSP:
+        if (m68k_feature(env, M68K_FEATURE_M68020)
+         || m68k_feature(env, M68K_FEATURE_M68030)
+         || m68k_feature(env, M68K_FEATURE_M68040)) {
             return env->sp[M68K_SSP];
+        }
+        break;
     /* MC680[234]0 */
     case M68K_CR_ISP:
+        if (m68k_feature(env, M68K_FEATURE_M68020)
+         || m68k_feature(env, M68K_FEATURE_M68030)
+         || m68k_feature(env, M68K_FEATURE_M68040)) {
             return env->sp[M68K_ISP];
-    /* MC68040/MC68LC040 */
+        }
-    case M68K_CR_URP:
+        break;
-        return env->mmu.urp;
     /* MC68040/MC68LC040 */
     case M68K_CR_ITT0: /* MC68EC040 only: M68K_CR_IACR0 */
+        if (m68k_feature(env, M68K_FEATURE_M68040)) {
             return env->mmu.ttr[M68K_ITTR0];
+        }
+        break;
     /* MC68040/MC68LC040 */
     case M68K_CR_ITT1: /* MC68EC040 only: M68K_CR_IACR1 */
+        if (m68k_feature(env, M68K_FEATURE_M68040)) {
             return env->mmu.ttr[M68K_ITTR1];
+        }
+        break;
     /* MC68040/MC68LC040 */
     case M68K_CR_DTT0: /* MC68EC040 only: M68K_CR_DACR0 */
+        if (m68k_feature(env, M68K_FEATURE_M68040)) {
             return env->mmu.ttr[M68K_DTTR0];
+        }
+        break;
     /* MC68040/MC68LC040 */
     case M68K_CR_DTT1: /* MC68EC040 only: M68K_CR_DACR1 */
+        if (m68k_feature(env, M68K_FEATURE_M68040)) {
             return env->mmu.ttr[M68K_DTTR1];
+        }
+        break;
     /* Unimplemented Registers */
     case M68K_CR_CAAR:
     case M68K_CR_PCR:
     case M68K_CR_BUSCR:
-        break;
-    }
         cpu_abort(env_cpu(env), "Unimplemented control register read 0x%x\n",
                   reg);
     }
 
+    /* Invalid control registers will generate an exception. */
+    raise_exception_ra(env, EXCP_ILLEGAL, 0);
+
+    return 0;
+}
+
 void HELPER(set_macsr)(CPUM68KState *env, uint32_t val)
 {
     uint32_t acc;

qemu/target/m68k/translate.c

@@ -6263,7 +6263,7 @@ void register_m68k_insns (CPUM68KState *env)
     BASE(stop,      4e72, ffff);
     BASE(rte,       4e73, ffff);
     INSN(cf_movec,  4e7b, ffff, CF_ISA_A);
-    INSN(m68k_movec, 4e7a, fffe, M68000);
+    INSN(m68k_movec, 4e7a, fffe, MOVEC);
 #endif
     BASE(nop,       4e71, ffff);
     INSN(rtd,       4e74, ffff, RTD);