gen/genlib/misc: add BitSlip

diff --git a/litex/gen/genlib/misc.py b/litex/gen/genlib/misc.py
index 42ad878cbf902a8210c906ce7b8cbbaef2a48528..a28e30d96d9f1358111cbb59e2c59165c74faeba 100644 (file)
--- a/litex/gen/genlib/misc.py
+++ b/litex/gen/genlib/misc.py
@@ -86,3 +86,19 @@ class WaitTimer(Module):
             If(self.wait,
                 If(~self.done, count.eq(count - 1))
             ).Else(count.eq(count.reset))
+
+
+class BitSlip(Module):
+    def __init__(self, dw):
+        self.i = Signal(dw)
+        self.o = Signal(dw)
+        self.value = Signal(max=dw)
+
+        # # #
+
+        r = Signal(2*dw)
+        self.sync += r.eq(Cat(r[dw:], self.i))
+        cases = {}
+        for i in range(dw):
+            cases[i] = self.o.eq(r[i:dw+i])
+        self.sync += Case(self.value, cases)