Enable clocks for UART1 and 2

Recent change in IDF disables those clocks at boot. This change should
help with that.

Fixes: espressif/esp-idf#975

Author: me-no-dev

cores/esp32/esp32-hal-uart.c

@@ -26,6 +26,7 @@
 #include "soc/uart_struct.h"
 #include "soc/io_mux_reg.h"
 #include "soc/gpio_sig_map.h"
+#include "soc/dport_reg.h"
 
 #define ETS_UART_INUM  5
 #define ETS_UART2_INUM  ETS_UART_INUM
@@ -190,7 +191,13 @@ uart_t* uartBegin(uint8_t uart_nr, uint32_t baudrate, uint32_t config, int8_t rx
             return NULL;
         }
     }
-
+    if(uart_nr == 1){
+        DPORT_SET_PERI_REG_MASK(DPORT_PERIP_CLK_EN_REG, DPORT_UART1_CLK_EN);
+        DPORT_CLEAR_PERI_REG_MASK(DPORT_PERIP_RST_EN_REG, DPORT_UART1_RST);
+    } else if(uart_nr == 2){
+        DPORT_SET_PERI_REG_MASK(DPORT_PERIP_CLK_EN_REG, DPORT_UART2_CLK_EN);
+        DPORT_CLEAR_PERI_REG_MASK(DPORT_PERIP_RST_EN_REG, DPORT_UART2_RST);
+    }
     uartFlush(uart);
     uartSetBaudRate(uart, baudrate);
     UART_MUTEX_LOCK();