target/arm: Extend arm_fi_to_lfsc to level -1

With FEAT_LPA2, rather than introducing translation level 4,
we introduce level -1, below the current level 0.  Extend
arm_fi_to_lfsc to handle these faults.

Assert that this new translation level does not leak into
fault types for which it is not defined, which allows some
masking of fi->level to be removed.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220301215958.157011-12-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 29 insertions, 6 deletions

diff --git a/target/arm/internals.h b/target/arm/internals.h
index 3d3d41b..00af41d 100644
--- a/target/arm/internals.h
+++ b/target/arm/internals.h
@@ -462,28 +462,51 @@ static inline uint32_t arm_fi_to_lfsc(ARMMMUFaultInfo *fi)
     case ARMFault_None:
         return 0;
     case ARMFault_AddressSize:
-        fsc = fi->level & 3;
+        assert(fi->level >= -1 && fi->level <= 3);
+        if (fi->level < 0) {
+            fsc = 0b101001;
+        } else {
+            fsc = fi->level;
+        }
         break;
     case ARMFault_AccessFlag:
-        fsc = (fi->level & 3) | (0x2 << 2);
+        assert(fi->level >= 0 && fi->level <= 3);
+        fsc = 0b001000 | fi->level;
         break;
     case ARMFault_Permission:
-        fsc = (fi->level & 3) | (0x3 << 2);
+        assert(fi->level >= 0 && fi->level <= 3);
+        fsc = 0b001100 | fi->level;
         break;
     case ARMFault_Translation:
-        fsc = (fi->level & 3) | (0x1 << 2);
+        assert(fi->level >= -1 && fi->level <= 3);
+        if (fi->level < 0) {
+            fsc = 0b101011;
+        } else {
+            fsc = 0b000100 | fi->level;
+        }
         break;
     case ARMFault_SyncExternal:
         fsc = 0x10 | (fi->ea << 12);
         break;
     case ARMFault_SyncExternalOnWalk:
-        fsc = (fi->level & 3) | (0x5 << 2) | (fi->ea << 12);
+        assert(fi->level >= -1 && fi->level <= 3);
+        if (fi->level < 0) {
+            fsc = 0b010011;
+        } else {
+            fsc = 0b010100 | fi->level;
+        }
+        fsc |= fi->ea << 12;
         break;
     case ARMFault_SyncParity:
         fsc = 0x18;
         break;
     case ARMFault_SyncParityOnWalk:
-        fsc = (fi->level & 3) | (0x7 << 2);
+        assert(fi->level >= -1 && fi->level <= 3);
+        if (fi->level < 0) {
+            fsc = 0b011011;
+        } else {
+            fsc = 0b011100 | fi->level;
+        }
         break;
     case ARMFault_AsyncParity:
         fsc = 0x19;