change reqiured to work with little endian interpreter.

3 files changed, 15 insertions, 4 deletions

diff --git a/mips/mips_insts.sail b/mips/mips_insts.sail
index 07ded875..285d3011 100644
--- a/mips/mips_insts.sail
+++ b/mips/mips_insts.sail
@@ -1129,7 +1129,7 @@ function clause execute (Load(width, signed, linked, base, rt, offset)) =
                 {
                   CP0LLBit  := 0b1;
                   CP0LLAddr := pAddr;
-                  MEMr_reserve(pAddr, wordWidthBytes(width));
+                  MEMr_reserve_wrapper(pAddr, wordWidthBytes(width));
                 }
               else
                 MEMr_wrapper(pAddr, wordWidthBytes(width));
diff --git a/mips/mips_prelude.sail b/mips/mips_prelude.sail
index 3643d211..22e2f138 100644
--- a/mips/mips_prelude.sail
+++ b/mips/mips_prelude.sail
@@ -574,6 +574,14 @@ function (bool) isAddressAligned (addr, (WordType) wordType) =
   let a = unsigned(addr) in
   ((a quot alignment_width) == (a + wordWidthBytes(wordType) - 1) quot alignment_width)
 
+val forall Nat 'W. bit[8 * 'W] -> bit[8 * 'W] effect pure reverse_endianness
+function rec forall Nat 'W . bit[8 * 'W] reverse_endianness ((bit[8 * 'W]) value) =
+{
+    (nat) width := length(value);
+    if width <= 8 then value
+    else value[7..0] : reverse_endianness(value[(width - 1) .. 8])
+}
+
 function forall Nat 'n. (bit[8 * 'n]) effect { rmem } MEMr_wrapper ((bit[64]) addr, ([:'n:]) size) =
     if (addr == 0x000000007f000000) then
       {
@@ -586,4 +594,7 @@ function forall Nat 'n. (bit[8 * 'n]) effect { rmem } MEMr_wrapper ((bit[64]) ad
     else if (addr == 0x000000007f000004) then
       mask(0x000000000004ffff) (* Always plenty of write space available and jtag activity *)
     else
-      MEMr(addr, size)
+      reverse_endianness(MEMr(addr, size)) (* MEMr assumes little endian *)
+
+function forall Nat 'n. (bit[8 * 'n]) effect { rmem } MEMr_reserve_wrapper ((bit[64]) addr , ([:'n:]) size) =
+    reverse_endianness(MEMr_reserve(addr, size))
diff --git a/mips/mips_wrappers.sail b/mips/mips_wrappers.sail
index 357aa9dd..b70853f0 100644
--- a/mips/mips_wrappers.sail
+++ b/mips/mips_wrappers.sail
@@ -42,13 +42,13 @@ function unit effect {wmem} MEMw_wrapper(addr, size, data) =
         UART_WRITTEN := 1;
       } else {
         MEMea(addr, size);
-        MEMval(addr, size, data);
+        MEMval(addr, size, reverse_endianness(data));
       }
 
 function bool effect {wmem} MEMw_conditional_wrapper(addr, size, data) =
     {
       MEMea_conditional(addr, size);
-      MEMval_conditional(addr, size, data)
+      MEMval_conditional(addr, size, reverse_endianness(data))
     }
 
 function bit[64] addrWrapper((bit[64]) addr, (MemAccessType) accessType, (WordType) width) =