cpu/stm32l1: add flashpage support

cpu/stm32l1/Makefile.features

@@ -1 +1,4 @@
+FEATURES_PROVIDED += periph_flashpage
+FEATURES_PROVIDED += periph_flashpage_raw
+
 -include $(RIOTCPU)/stm32_common/Makefile.features

cpu/stm32l1/include/cpu_conf.h

@@ -72,10 +72,30 @@ extern "C" {
 #define CPU_FLASH_BASE                  FLASH_BASE
 /** @} */
 
+/**
+ * @name   Flash page configuration
+ * @{
+ */
+#if defined(CPU_MODEL_STM32L152RE) || defined(CPU_MODEL_STM32L151RC)
+#define FLASHPAGE_SIZE             (256U)
+#if defined(CPU_MODEL_STM32L152RE)
+#define FLASHPAGE_NUMOF            (2048U)    /* 512KB */
+#endif
+#if defined(CPU_MODEL_STM32L151RC)
+#define FLASHPAGE_NUMOF            (1024U)    /* 256KB */
+#endif
+#endif
+/* The minimum block size which can be written is 4B. However, the erase
+ * block is always FLASHPAGE_SIZE.
+ */
+#define FLASHPAGE_RAW_BLOCKSIZE    (4U)
+/* Writing should be always 4 bytes aligned */
+#define FLASHPAGE_RAW_ALIGNMENT    (4U)
+/** @} */
+
 #ifdef __cplusplus
 }
 #endif
 
 #endif /* CPU_CONF_H */
 /** @} */
-/** @} */