From a738739acd797d7ffaa14967976d3fe66cabda4f Mon Sep 17 00:00:00 2001
From: Tim 'mithro' Ansell <me@mith.ro>
Date: Mon, 30 Dec 2019 16:10:57 +0100
Subject: [PATCH] Improve the invalid CPU type error message.

---
 litex/soc/integration/soc_core.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/litex/soc/integration/soc_core.py b/litex/soc/integration/soc_core.py
index 61281f02f..22e714875 100644
--- a/litex/soc/integration/soc_core.py
+++ b/litex/soc/integration/soc_core.py
@@ -167,9 +167,13 @@ class SoCCore(Module):
         if cpu_type is not None:
             if cpu_variant is not None:
                 self.config["CPU_VARIANT"] = str(cpu_variant.split('+')[0]).upper()
+
             # Check type
             if cpu_type not in cpu.CPUS.keys():
-                raise ValueError("Unsupported CPU type: {}".format(cpu_type))
+                raise ValueError(
+                    "Unsupported CPU type: {} -- supported CPU types: {}".format(
+                        cpu_type, ", ".join(cpu.CPUS.keys())))
+
             # Declare the CPU
             self.submodules.cpu = cpu.CPUS[cpu_type](platform, self.cpu_variant)
             if cpu_type == "microwatt":