serial/xlnx_ps: add common Xilinx UART Peripheral System (XUARTPS) support

This PR adds complete driver support for the Xilinx UART Peripheral System (XUARTPS)
in the NuttX serial driver framework. The implementation includes the core driver code
(uart_xlnx_ps.c), configuration files (Kconfig-xlnxps), header definitions (uart_xlnx_ps.h),
and integration with the existing NuttX build system (CMakeLists.txt, Make.defs, Kconfig).

The driver supports UART0 configuration with customizable parameters (base address,
clock frequency, IRQ number, baud rate, parity, data bits, stop bits), RX/TX buffer sizing,
hardware flow control (RTS/CTS), interrupt-driven data transfer, and console mapping for XUARTPS UART0.
It also provides standard serial driver operations (setup, shutdown, attach/detach, ioctl, send/receive)
and early serial initialization for boot-time console access.

Signed-off-by: chao an <anchao.archer@bytedance.com>

drivers/serial/CMakeLists.txt

@@ -46,6 +46,10 @@ if(CONFIG_UART_PL011)
   list(APPEND SRCS uart_pl011.c)
 endif()
 
+if(CONFIG_UART_XLNXPS)
+  list(APPEND SRCS uart_xlnx_ps.c)
+endif()
+
 if(CONFIG_RPMSG_UART)
   list(APPEND SRCS uart_rpmsg.c)
 endif()

drivers/serial/Kconfig

@@ -114,6 +114,14 @@ if UART_PL011
 source "drivers/serial/Kconfig-pl011"
 endif
 
+menuconfig UART_XLNXPS
+	bool "Xilinx UART Peripheral System (XUARTPS) Chip support"
+	default n
+
+if UART_XLNXPS
+source "drivers/serial/Kconfig-xlnxps"
+endif # UART_XLNXPS
+
 menuconfig CMSDK_UART
 	bool "CMSDK UART Chip support"
 	select ARCH_HAVE_SERIAL_TERMIOS

drivers/serial/Kconfig-xlnxps

@@ -0,0 +1,128 @@
+#
+# For a description of the syntax of this configuration file,
+# see the file kconfig-language.txt in the NuttX tools repository.
+#
+
+if UART_XLNXPS
+
+config XLNXPS_SERIAL_DISABLE_REORDERING
+	bool "Disable reordering of ttySx devices."
+	default n
+	---help---
+		NuttX per default reorders the serial ports (/dev/ttySx) so that the
+		console is always on /dev/ttyS0. If more than one UART is in use this
+		can, however, have the side-effect that all port mappings
+		(hardware USART1 -> /dev/ttyS0) change if the console is moved to another
+		UART.  This option disables that re-ordering for XLNXPS UARTs.
+
+config UART_XLNXPS0
+	bool "XLNXPS UART0"
+	default n
+
+if UART_XLNXPS0
+
+config UART_XLNXPS0_BASE
+	hex "XLNXPS UART0 base address"
+	default 0x0
+
+config UART_XLNXPS0_CLOCK
+	int "XLNXPS UART0 clock"
+	default 0
+
+config UART_XLNXPS0_IRQ
+	int "XLNXPS UART0 IRQ number"
+	default 0
+
+config UART_XLNXPS0_BAUD
+	int "XLNXPS UART0 BAUD"
+	default 115200
+
+config UART_XLNXPS0_PARITY
+	int "XLNXPS UART0 parity"
+	default 0
+	range 0 2
+	---help---
+		XLNXPS UART0 parity.  0=None, 1=Odd, 2=Even.  Default: None
+
+config UART_XLNXPS0_BITS
+	int "XLNXPS UART0 number of bits"
+	default 8
+	---help---
+		XLNXPS UART0 number of bits.  Default: 8
+
+config UART_XLNXPS0_2STOP
+	int "XLNXPS UART0 two stop bits"
+	default 0
+	---help---
+		0=1 stop bit, 1=Two stop bits.  Default: 1 stop bit
+
+config UART_XLNXPS0_RX_TRIGGER
+  int "XLNXPS UART0 RX interrupt trigger level"
+	default 2
+	range 0 3
+
+config UART_XLNXPS0_RXBUFSIZE
+	int "XLNXPS UART0 Rx buffer size"
+	default 256
+	---help---
+		XLNXPS UART0 Rx buffer size.  Default: 256
+
+config UART_XLNXPS0_TXBUFSIZE
+	int "XLNXPS UART0 Tx buffer size"
+	default 256
+	---help---
+		XLNXPS UART0 Tx buffer size.  Default: 256
+
+config UART_XLNXPS0_IFLOWCONTROL
+	bool "XLNXPS UART0 RTS flow control"
+	default n
+	select SERIAL_IFLOWCONTROL
+	---help---
+		Enable XLNXPS UART0 RTS flow control
+
+config UART_XLNXPS0_OFLOWCONTROL
+	bool "XLNXPS UART0 CTS flow control"
+	default n
+	select SERIAL_OFLOWCONTROL
+	---help---
+		Enable XLNXPS UART0 CTS flow control
+
+endif # UART_XLNXPS0
+
+choice
+	prompt "XLNXPS Serial Console"
+	default XLNXPS_NO_SERIAL_CONSOLE
+	depends on DEV_CONSOLE
+
+config UART_XLNXPS0_SERIAL_CONSOLE
+	bool "XLNXPS UART0 serial console"
+	depends on UART_XLNXPS0
+	select SERIAL_CONSOLE
+
+config XLNXPS_NO_SERIAL_CONSOLE
+	bool "No XLNXPS serial console"
+
+endchoice # XLNXPS Serial Console
+
+config XLNXPS_SUPRESS_CONFIG
+	bool "Suppress XLNXPS configuration"
+	default n
+
+config XLNXPS_SUPRESS_INITIAL_CONFIG
+	bool "Suppress initial XLNXPS configuration"
+	depends on !XLNXPS_SUPRESS_CONFIG
+	default n
+	---help---
+		This option is useful, for example, if you are using a bootloader
+		that configures the UART_XLNXPS.  In that case, you may want to
+		just leave the existing console configuration in place.  Default: n
+
+config SERIAL_UART_ARCH_MMIO
+	bool "Platform access register through the memory mapping"
+	default n
+
+config SERIAL_UART_ARCH_IOCTL
+	bool "Platform has own custom IOCTL"
+	default n
+
+endif # UART_XLNXPS

drivers/serial/Make.defs

@@ -58,6 +58,10 @@ ifeq ($(CONFIG_UART_HOSTFS),y)
   CSRCS += uart_hostfs.c
 endif
 
+ifeq ($(CONFIG_UART_XLNXPS),y)
+  CSRCS += uart_xlnx_ps.c
+endif
+
 # Pseudo-terminal support
 
 ifeq ($(CONFIG_PSEUDOTERM),y)

include/nuttx/serial/uart_xlnx_ps.h

@@ -0,0 +1,48 @@
+/****************************************************************************
+ * include/nuttx/serial/uart_xlnx_ps.h
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __INCLUDE_NUTTX_SERIAL_UART_XLNXPS_H
+#define __INCLUDE_NUTTX_SERIAL_UART_XLNXPS_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#ifdef CONFIG_UART_XLNXPS
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions Prototypes
+ ****************************************************************************/
+
+void xlnxps_earlyserialinit(void);
+
+void xlnxps_serialinit(void);
+
+#endif  /* CONFIG_UART_XLNXPS */
+
+#endif /* __INCLUDE_NUTTX_SERIAL_UART_XLNXPS_H */