diff --git a/artiq/compiler/transforms/llvm_ir_generator.py b/artiq/compiler/transforms/llvm_ir_generator.py
index 7d7ca6344..149d45f4a 100644
--- a/artiq/compiler/transforms/llvm_ir_generator.py
+++ b/artiq/compiler/transforms/llvm_ir_generator.py
@@ -1103,6 +1103,14 @@ class LLVMIRGenerator:
             return self.map(insn.operands[0])
         elif insn.op == "now_mu":
             if self.target.now_pinning:
+                # Word swap now.old for little endian target
+                # Most significant word is stored in lower address (see generated csr.rs)
+                if self.target.little_endian:
+                    llnow_raw = self.llbuilder.load(self.llbuiltin("now"), name=insn.name)
+                    llnow_lo = self.llbuilder.shl(llnow_raw, ll.Constant(lli64, 32))
+                    llnow_hi = self.llbuilder.lshr(llnow_raw, ll.Constant(lli64, 32))
+                    return self.llbuilder.or_(llnow_lo, llnow_hi)
+                else:
                 return self.llbuilder.load(self.llbuiltin("now"), name=insn.name)
             else:
                 return self.llbuilder.call(self.llbuiltin("now_mu"), [])
@@ -1114,8 +1122,6 @@ class LLVMIRGenerator:
                 lltime_lo = self.llbuilder.trunc(lltime, lli32)
                 llnow_hiptr = self.llbuilder.bitcast(self.llbuiltin("now"), lli32.as_pointer())
                 llnow_loptr = self.llbuilder.gep(llnow_hiptr, [self.llindex(1)])
-                if self.target.little_endian:
-                    lltime_hi, lltime_lo = lltime_lo, lltime_hi
                 llstore_hi = self.llbuilder.store_atomic(lltime_hi, llnow_hiptr, ordering="seq_cst", align=4)
                 llstore_lo = self.llbuilder.store_atomic(lltime_lo, llnow_loptr, ordering="seq_cst", align=4)
                 return llstore_lo
@@ -1127,13 +1133,17 @@ class LLVMIRGenerator:
             if self.target.now_pinning:
                 llnowptr = self.llbuiltin("now")
                 llnow = self.llbuilder.load(llnowptr, name="now.old")
+                # Word swap now.old for little endian target
+                # Most significant word is stored in lower address (see generated csr.rs)
+                if self.target.little_endian:
+                    llnow_lo = self.llbuilder.shl(llnow, ll.Constant(lli64, 32))
+                    llnow_hi = self.llbuilder.lshr(llnow, ll.Constant(lli64, 32))
+                    llnow = self.llbuilder.or_(llnow_lo, llnow_hi)
                 lladjusted = self.llbuilder.add(llnow, llinterval, name="now.new")
                 lladjusted_hi = self.llbuilder.trunc(self.llbuilder.lshr(lladjusted, ll.Constant(lli64, 32)), lli32)
                 lladjusted_lo = self.llbuilder.trunc(lladjusted, lli32)
                 llnow_hiptr = self.llbuilder.bitcast(llnowptr, lli32.as_pointer())
                 llnow_loptr = self.llbuilder.gep(llnow_hiptr, [self.llindex(1)])
-                if self.target.little_endian:
-                    lladjusted_hi, lladjusted_lo = lladjusted_lo, lladjusted_hi
                 llstore_hi = self.llbuilder.store_atomic(lladjusted_hi, llnow_hiptr, ordering="seq_cst", align=4)
                 llstore_lo = self.llbuilder.store_atomic(lladjusted_lo, llnow_loptr, ordering="seq_cst", align=4)
                 return llstore_lo