diff --git a/litex/build/altera/platform.py b/litex/build/altera/platform.py
index a5caa4d52..ce6821797 100644
--- a/litex/build/altera/platform.py
+++ b/litex/build/altera/platform.py
@@ -22,7 +22,7 @@ class AlteraPlatform(GenericPlatform):
         if toolchain == "quartus":
             self.toolchain = quartus.AlteraQuartusToolchain()
         else:
-            raise ValueError("Unknown toolchain")
+            raise ValueError(f"Unknown toolchain {toolchain}")
 
     def add_ip(self, filename):
         self.ips.add((os.path.abspath(filename)))
diff --git a/litex/build/anlogic/platform.py b/litex/build/anlogic/platform.py
index b82092b93..77f111cbf 100644
--- a/litex/build/anlogic/platform.py
+++ b/litex/build/anlogic/platform.py
@@ -20,7 +20,7 @@ class AnlogicPlatform(GenericPlatform):
         if toolchain == "td":
             self.toolchain = anlogic.TangDinastyToolchain()
         else:
-            raise ValueError("Unknown toolchain")
+            raise ValueError(f"Unknown toolchain {toolchain}")
 
     def get_verilog(self, *args, special_overrides=dict(), **kwargs):
         so = dict(common.anlogic_special_overrides)
diff --git a/litex/build/efinix/platform.py b/litex/build/efinix/platform.py
index 67ed060cb..7fbd758cb 100644
--- a/litex/build/efinix/platform.py
+++ b/litex/build/efinix/platform.py
@@ -41,7 +41,7 @@ class EfinixPlatform(GenericPlatform):
         if toolchain == "efinity":
             self.toolchain = efinity.EfinityToolchain(self.efinity_path)
         else:
-            raise ValueError("Unknown toolchain")
+            raise ValueError(f"Unknown toolchain {toolchain}")
 
         self.parser = EfinixDbParser(self.efinity_path, self.device)
         self.pll_available = self.parser.get_block_instance_names('pll')
diff --git a/litex/build/gowin/platform.py b/litex/build/gowin/platform.py
index bc0d69dd9..d6a464394 100644
--- a/litex/build/gowin/platform.py
+++ b/litex/build/gowin/platform.py
@@ -27,7 +27,7 @@ class GowinPlatform(GenericPlatform):
         elif toolchain == "apicula":
             raise ValueError("Apicula toolchain needs more work")
         else:
-            raise ValueError("Unknown toolchain")
+            raise ValueError(f"Unknown toolchain {toolchain}")
 
     def get_verilog(self, *args, special_overrides=dict(), **kwargs):
         so = dict(common.gowin_special_overrides)
diff --git a/litex/build/lattice/platform.py b/litex/build/lattice/platform.py
index 168ef0d0a..3e95f8322 100644
--- a/litex/build/lattice/platform.py
+++ b/litex/build/lattice/platform.py
@@ -27,7 +27,7 @@ class LatticePlatform(GenericPlatform):
         elif toolchain == "oxide":
             self.toolchain = oxide.LatticeOxideToolchain()
         else:
-            raise ValueError("Unknown toolchain")
+            raise ValueError(f"Unknown toolchain {toolchain}")
 
     def get_verilog(self, *args, special_overrides=dict(), **kwargs):
         so = dict()  # No common overrides between ECP5 and iCE40.
diff --git a/litex/build/microsemi/platform.py b/litex/build/microsemi/platform.py
index ce658d6fc..ac4aa6938 100644
--- a/litex/build/microsemi/platform.py
+++ b/litex/build/microsemi/platform.py
@@ -17,7 +17,7 @@ class MicrosemiPlatform(GenericPlatform):
         if toolchain == "libero_soc_polarfire":
             self.toolchain = libero_soc.MicrosemiLiberoSoCPolarfireToolchain()
         else:
-            raise ValueError("Unknown toolchain")
+            raise ValueError(f"Unknown toolchain {toolchain}")
 
     def get_verilog(self, *args, special_overrides=dict(), **kwargs):
         so = dict()
diff --git a/litex/build/quicklogic/platform.py b/litex/build/quicklogic/platform.py
index 44c854f6a..fbd200cb2 100644
--- a/litex/build/quicklogic/platform.py
+++ b/litex/build/quicklogic/platform.py
@@ -19,7 +19,7 @@ class QuickLogicPlatform(GenericPlatform):
         if toolchain == "symbiflow":
             self.toolchain = symbiflow.SymbiflowToolchain()
         else:
-            raise ValueError("Unknown toolchain")
+            raise ValueError(f"Unknown toolchain {toolchain}")
 
     def get_verilog(self, *args, special_overrides=dict(), **kwargs):
         so = dict(common.quicklogic_special_overrides)
diff --git a/litex/build/sim/platform.py b/litex/build/sim/platform.py
index 35456ae57..aa8734321 100644
--- a/litex/build/sim/platform.py
+++ b/litex/build/sim/platform.py
@@ -24,7 +24,7 @@ class SimPlatform(GenericPlatform):
         if toolchain == "verilator":
             self.toolchain = verilator.SimVerilatorToolchain()
         else:
-            raise ValueError("Unknown toolchain")
+            raise ValueError(f"Unknown toolchain {toolchain}")
         # we must always request the sim_trace signal
         self.trace = self.request("sim_trace")
 
diff --git a/litex/build/xilinx/platform.py b/litex/build/xilinx/platform.py
index cb7fd2023..e0e96be03 100644
--- a/litex/build/xilinx/platform.py
+++ b/litex/build/xilinx/platform.py
@@ -36,7 +36,7 @@ class XilinxPlatform(GenericPlatform):
         #    import symbiflow_nextpnr 
         #    self.toolchain = symbiflow_nextpnr.SymbiflowNextpnrToolchain()
         else:
-            raise ValueError("Unknown toolchain")
+            raise ValueError(f"Unknown toolchain {toolchain}")
 
     def add_edif(self, filename):
         self.edifs.add((os.path.abspath(filename)))