Merge remote-tracking branch 'remotes/lalrae/tags/mips-20151124' into staging

MIPS patches 2015-11-24

Changes:
* Fixes for enabling/disabling 64-bit addressing

# gpg: Signature made Tue 24 Nov 2015 14:54:35 GMT using RSA key ID 0B29DA6B
# gpg: Good signature from "Leon Alrae <leon.alrae@imgtec.com>"

* remotes/lalrae/tags/mips-20151124:
  target-mips: flush QEMU TLB when disabling 64-bit addressing
  target-mips: Fix exceptions while UX=0

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

3 files changed, 29 insertions, 14 deletions

diff --git a/target-mips/cpu.h b/target-mips/cpu.h
index fa919c1..89c01f7 100644
--- a/target-mips/cpu.h
+++ b/target-mips/cpu.h
@@ -961,6 +961,15 @@ static inline void compute_hflags(CPUMIPSState *env)
 }
 
 #ifndef CONFIG_USER_ONLY
+static inline void cpu_mips_tlb_flush(CPUMIPSState *env, int flush_global)
+{
+    MIPSCPU *cpu = mips_env_get_cpu(env);
+
+    /* Flush qemu's TLB and discard all shadowed entries.  */
+    tlb_flush(CPU(cpu), flush_global);
+    env->tlb->tlb_in_use = env->tlb->nb_tlb;
+}
+
 /* Called for updates to CP0_Status.  */
 static inline void sync_c0_status(CPUMIPSState *env, CPUMIPSState *cpu, int tc)
 {
@@ -999,6 +1008,7 @@ static inline void sync_c0_status(CPUMIPSState *env, CPUMIPSState *cpu, int tc)
 static inline void cpu_mips_store_status(CPUMIPSState *env, target_ulong val)
 {
     uint32_t mask = env->CP0_Status_rw_bitmask;
+    target_ulong old = env->CP0_Status;
 
     if (env->insn_flags & ISA_MIPS32R6) {
         bool has_supervisor = extract32(mask, CP0St_KSU, 2) == 0x3;
@@ -1014,7 +1024,13 @@ static inline void cpu_mips_store_status(CPUMIPSState *env, target_ulong val)
         mask &= ~(((1 << CP0St_SR) | (1 << CP0St_NMI)) & val);
     }
 
-    env->CP0_Status = (env->CP0_Status & ~mask) | (val & mask);
+    env->CP0_Status = (old & ~mask) | (val & mask);
+#if defined(TARGET_MIPS64)
+    if ((env->CP0_Status ^ old) & (old & (7 << CP0St_UX))) {
+        /* Access to at least one of the 64-bit segments has been disabled */
+        cpu_mips_tlb_flush(env, 1);
+    }
+#endif
     if (env->CP0_Config3 & (1 << CP0C3_MT)) {
         sync_c0_status(env, env, env->current_tc);
     } else {
diff --git a/target-mips/helper.c b/target-mips/helper.c
index b3fe816..118072a 100644
--- a/target-mips/helper.c
+++ b/target-mips/helper.c
@@ -524,6 +524,10 @@ void mips_cpu_do_interrupt(CPUState *cs)
  enter_debug_mode:
         if (env->insn_flags & ISA_MIPS3) {
             env->hflags |= MIPS_HFLAG_64;
+            if (!(env->insn_flags & ISA_MIPS64R6) ||
+                env->CP0_Status & (1 << CP0St_KX)) {
+                env->hflags &= ~MIPS_HFLAG_AWRAP;
+            }
         }
         env->hflags |= MIPS_HFLAG_DM | MIPS_HFLAG_CP0;
         env->hflags &= ~(MIPS_HFLAG_KSU);
@@ -548,6 +552,10 @@ void mips_cpu_do_interrupt(CPUState *cs)
         env->CP0_Status |= (1 << CP0St_ERL) | (1 << CP0St_BEV);
         if (env->insn_flags & ISA_MIPS3) {
             env->hflags |= MIPS_HFLAG_64;
+            if (!(env->insn_flags & ISA_MIPS64R6) ||
+                env->CP0_Status & (1 << CP0St_KX)) {
+                env->hflags &= ~MIPS_HFLAG_AWRAP;
+            }
         }
         env->hflags |= MIPS_HFLAG_CP0;
         env->hflags &= ~(MIPS_HFLAG_KSU);
@@ -725,6 +733,10 @@ void mips_cpu_do_interrupt(CPUState *cs)
             env->CP0_Status |= (1 << CP0St_EXL);
             if (env->insn_flags & ISA_MIPS3) {
                 env->hflags |= MIPS_HFLAG_64;
+                if (!(env->insn_flags & ISA_MIPS64R6) ||
+                    env->CP0_Status & (1 << CP0St_KX)) {
+                    env->hflags &= ~MIPS_HFLAG_AWRAP;
+                }
             }
             env->hflags |= MIPS_HFLAG_CP0;
             env->hflags &= ~(MIPS_HFLAG_KSU);
diff --git a/target-mips/op_helper.c b/target-mips/op_helper.c
index 056d53b..d2c98c9 100644
--- a/target-mips/op_helper.c
+++ b/target-mips/op_helper.c
@@ -23,10 +23,6 @@
 #include "exec/cpu_ldst.h"
 #include "sysemu/kvm.h"
 
-#ifndef CONFIG_USER_ONLY
-static inline void cpu_mips_tlb_flush (CPUMIPSState *env, int flush_global);
-#endif
-
 /*****************************************************************************/
 /* Exceptions processing helpers */
 
@@ -1846,15 +1842,6 @@ target_ulong helper_yield(CPUMIPSState *env, target_ulong arg)
 
 #ifndef CONFIG_USER_ONLY
 /* TLB management */
-static void cpu_mips_tlb_flush (CPUMIPSState *env, int flush_global)
-{
-    MIPSCPU *cpu = mips_env_get_cpu(env);
-
-    /* Flush qemu's TLB and discard all shadowed entries.  */
-    tlb_flush(CPU(cpu), flush_global);
-    env->tlb->tlb_in_use = env->tlb->nb_tlb;
-}
-
 static void r4k_mips_tlb_flush_extra (CPUMIPSState *env, int first)
 {
     /* Discard entries from env->tlb[first] onwards.  */