soc: arm: stm32l1: set voltage scaling to range1

Default Voltage scaling range selection (range2)
doesn't allow to configure Max frequency
switch to range1 to match any frequency

Signed-off-by: Alexandre Bourdiol <[email protected]>

Author: ABOSTM

soc/arm/st_stm32/stm32l1/soc.c

@@ -15,6 +15,8 @@
 #include <arch/arm/aarch32/cortex_m/cmsis.h>
 #include <linker/linker-defs.h>
 #include <string.h>
+#include <stm32_ll_bus.h>
+#include <stm32_ll_pwr.h>
 
 /**
  * @brief Perform basic hardware initialization at boot.
@@ -43,6 +45,13 @@ static int stm32l1_init(const struct device *arg)
 	/* At reset, system core clock is set to 2.1 MHz from MSI */
 	SystemCoreClock = 2097000;
 
+	/* Default Voltage scaling range selection (range2)
+	 * doesn't allow to configure Max frequency
+	 * switch to range1 to match any frequency
+	 */
+	LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_PWR);
+	LL_PWR_SetRegulVoltageScaling(LL_PWR_REGU_VOLTAGE_SCALE1);
+
 	return 0;
 }