driver: serial: Add serial driver support for Renesas RA8 devices

Add implementation of sci_b_uart for Renesas RA device

Signed-off-by: The Thanh. Nguyen <[email protected]>

Author: thenguyenyf

boards/renesas/ek_ra8m1/ek_ra8m1-pinctrl.dtsi

@@ -4,15 +4,15 @@
  */
 
 &pinctrl {
-	sci0_default: sci0_default {
+	sci9_default: sci9_default {
 		group1 {
 			/* tx */
-			psels = <RA_PSEL(RA_PSEL_SCI_0, 6, 9)>;
+			psels = <RA_PSEL(RA_PSEL_SCI_9, 10, 14)>;
 			drive-strength = "medium";
 		};
 		group2 {
 			/* rx */
-			psels = <RA_PSEL(RA_PSEL_SCI_0, 6, 10)>;
+			psels = <RA_PSEL(RA_PSEL_SCI_9, 10, 15)>;
 		};
 	};
 };

boards/renesas/ek_ra8m1/ek_ra8m1.dts

@@ -17,6 +17,8 @@
 	chosen {
 		zephyr,sram = &sram0;
 		zephyr,flash = &flash0;
+		zephyr,console = &uart9;
+		zephyr,shell-uart = &uart9;
 	};
 
 	leds {
@@ -64,6 +66,12 @@
 	status = "okay";
 };
 
+&sciclk {
+	clk_src = <RA_CLOCK_SOURCE_PLL1P>;
+	clk_div = <RA_SCI_CLOCK_DIV_4>;
+	status = "okay";
+};
+
 &ioport1 {
 	status = "okay";
 };
@@ -75,3 +83,13 @@
 &ioport6 {
 	status = "okay";
 };
+
+&sci9 {
+	pinctrl-0 = <&sci9_default>;
+	pinctrl-names = "default";
+	status = "okay";
+	uart9: uart {
+		current-speed = <115200>;
+		status = "okay";
+	};
+};

drivers/serial/CMakeLists.txt

@@ -75,7 +75,7 @@ zephyr_library_sources_ifdef(CONFIG_UART_INTEL_LW uart_intel_lw.c)
 zephyr_library_sources_ifdef(CONFIG_UART_RENESAS_RA uart_renesas_ra.c)
 zephyr_library_sources_ifdef(CONFIG_UART_ENE_KB1200 uart_ene_kb1200.c)
 zephyr_library_sources_ifdef(CONFIG_UART_RZT2M uart_rzt2m.c)
-
+zephyr_library_sources_ifdef(CONFIG_UART_RA8_SCI_B uart_renesas_ra8_sci_b.c)
 zephyr_library_sources_ifdef(CONFIG_USERSPACE   uart_handlers.c)
 
 if(CONFIG_UART_NATIVE_POSIX)

drivers/serial/Kconfig

@@ -278,4 +278,6 @@ rsource "Kconfig.ene"
 
 rsource "Kconfig.rzt2m"
 
+source "drivers/serial/Kconfig.renesas_ra8"
+
 endif # SERIAL

drivers/serial/Kconfig.renesas_ra

@@ -1,5 +1,4 @@
 # Copyright (c) 2023 TOKITA Hiroshi <[email protected]>
-# Copyright (c) 2024 Renesas Electronics Corporation
 # SPDX-License-Identifier: Apache-2.0
 
 config UART_RENESAS_RA

drivers/serial/Kconfig.renesas_ra8

@@ -0,0 +1,25 @@
+# Copyright (c) 2024 Renesas Electronics Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+config UART_RA8_SCI_B
+	bool "Renesas RA SCI_B UART"
+	default y
+	depends on DT_HAS_RENESAS_RA8_UART_SCI_B_ENABLED
+	select SERIAL_HAS_DRIVER
+	select SERIAL_SUPPORT_INTERRUPT
+	select SERIAL_SUPPORT_ASYNC
+	select USE_RA_FSP_SCI_B_UART
+	select USE_RA_FSP_DTC if UART_ASYNC_API
+	help
+	  Enable Renesas RA SCI_B UART Driver.
+
+if UART_RA8_SCI_B && (UART_INTERRUPT_DRIVEN || UART_ASYNC_API)
+
+config UART_RA_SCI_B_UART_FIFO_ENABLE
+	bool "RA SCI_B UART FIFO usage enable"
+	default y if UART_INTERRUPT_DRIVEN
+	default n if UART_ASYNC_API
+	help
+	  Enable RA SCI_B FIFO
+
+endif