From 21bbfbed1d95dae1cc26f3cd2493ab2b63a68606 Mon Sep 17 00:00:00 2001
From: Vincent Dupont <vincent@otakeys.com>
Date: Tue, 23 Jan 2018 11:49:13 +0100
Subject: [PATCH] stm32_common/stmclk: check if CLOCK_PLL_PREDIV is valid

---
 cpu/stm32_common/stmclk.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/cpu/stm32_common/stmclk.c b/cpu/stm32_common/stmclk.c
index 793c67167e..a7f5c03df9 100644
--- a/cpu/stm32_common/stmclk.c
+++ b/cpu/stm32_common/stmclk.c
@@ -225,6 +225,8 @@ void stmclk_init_sysclk(void)
     RCC->CFGR |= RCC_CFGR_PLLXTPRE; /* PREDIV == 2 */
 #elif CLOCK_PLL_PREDIV > 2
     RCC->CFGR2 = PLL_PREDIV;        /* PREDIV > 2 */
+#elif CLOCK_PLL_PREDIV == 0
+#error "CLOCK_PLL_PREDIV invalid"
 #endif
 #endif
     RCC->CR |= (RCC_CR_PLLON);