diff --git a/litex_boards/targets/versa_ecp5.py b/litex_boards/targets/versa_ecp5.py
index 5e0e2be8565056f603bad1b554ec3e528d069f50..62d201b273e76f82eeae6b9dd0513f218136cf46 100755
--- a/litex_boards/targets/versa_ecp5.py
+++ b/litex_boards/targets/versa_ecp5.py
@@ -76,6 +76,12 @@ class BaseSoC(SoCCore):
     def __init__(self, sys_clk_freq=int(75e6), with_ethernet=False, toolchain="trellis", **kwargs):
         platform = versa_ecp5.Platform(toolchain=toolchain)
 
+        # Fix ROM size for Microwatt
+        if with_ethernet:
+            kwargs["integrated_rom_size"]  = 0xb000
+        else:
+            kwargs["integrated_rom_size"]  = 0x9000
+
         # SoCCore -----------------------------------------_----------------------------------------
         SoCCore.__init__(self, platform, clk_freq=sys_clk_freq, **kwargs)