diff --git a/cpu/fe310/periph/uart.c b/cpu/fe310/periph/uart.c
index 80b3907774..7cc2581d74 100644
--- a/cpu/fe310/periph/uart.c
+++ b/cpu/fe310/periph/uart.c
@@ -86,13 +86,8 @@ int uart_init(uart_t dev, uint32_t baudrate, uart_rx_cb_t rx_cb, void *arg)
     /* Power on the device */
     uart_poweron(dev);
 
-    /* Calculate baudrate divisor given current CPU clk rate
-     * Ignore the first run (icache needs to be warm) */
-    uartDiv = PRCI_measure_mcycle_freq(1000, RTC_FREQ);
-    /* cppcheck-suppress redundantAssignment
-     * (reason: should ignore first cycle to get correct values) */
-    uartDiv = PRCI_measure_mcycle_freq(1000, RTC_FREQ);
-    uartDiv = uartDiv / baudrate;
+    /* Calculate baudrate divisor given current CPU clk rate */
+    uartDiv = cpu_freq() / baudrate;
 
     /* Enable UART 8-N-1 at given baudrate */
     _REG32(uart_config[dev].addr, UART_REG_DIV) = uartDiv;