qemu-armv7a/rpserver and rpproxy: support the rpmsg port uart

Use virtio-serial as the rpmsg-port-uart serial device, so we
can bringup the rpmsg-port-uart in qemu platform.

And update the documents:
nuttx/Documentation/platforms/arm/qemu/boards/qemu-armv7a/index.rst

Signed-off-by: Bowen Wang <wangbowen6@xiaomi.com>

Documentation/platforms/arm/qemu/boards/qemu-armv7a/index.rst

@@ -102,6 +102,9 @@ Steps for Using NuttX as IVSHMEM host and guest
       $ qemu-system-arm -cpu cortex-a7 -nographic -machine virt,highmem=off \
         -object memory-backend-file,id=shmmem-shmem0,mem-path=/dev/shm/ivshmem0,size=4194304,share=yes \
         -device ivshmem-plain,id=shmem0,memdev=shmmem-shmem0,addr=0xb \
+        -device virtio-serial-device,bus=virtio-mmio-bus.0 \
+        -chardev socket,path=/tmp/rpmsg_port_uart_socket,server=on,wait=off,id=foo \
+        -device virtconsole,chardev=foo \
         -kernel server/nuttx -nographic
 
   b. Start rpproxy_ivshmem::
@@ -109,6 +112,9 @@ Steps for Using NuttX as IVSHMEM host and guest
       $ qemu-system-arm -cpu cortex-a7 -nographic -machine virt,highmem=off \
         -object memory-backend-file,discard-data=on,id=shmmem-shmem0,mem-path=/dev/shm/ivshmem0,size=4194304,share=yes \
         -device ivshmem-plain,id=shmem0,memdev=shmmem-shmem0,addr=0xb \
+        -device virtio-serial-device,bus=virtio-mmio-bus.0 \
+        -chardev socket,path=/tmp/rpmsg_port_uart_socket,server=off,id=foo \
+        -device virtconsole,chardev=foo \
         -kernel proxy/nuttx -nographic
 
   c. Check the RPMSG Syslog in rpserver shell:

boards/arm/qemu/qemu-armv7a/configs/rpproxy_ivshmem/defconfig

@@ -42,6 +42,9 @@ CONFIG_DEBUG_PCI_WARN=y
 CONFIG_DEBUG_SYMBOLS=y
 CONFIG_DEVICE_TREE=y
 CONFIG_DEV_SIMPLE_ADDRENV=y
+CONFIG_DRIVERS_VIRTIO=y
+CONFIG_DRIVERS_VIRTIO_MMIO=y
+CONFIG_DRIVERS_VIRTIO_SERIAL=y
 CONFIG_EXAMPLES_HELLO=y
 CONFIG_EXAMPLES_RPMSGSOCKET=y
 CONFIG_EXPERIMENTAL=y
@@ -86,6 +89,7 @@ CONFIG_READLINE_CMD_HISTORY=y
 CONFIG_READLINE_TABCOMPLETION=y
 CONFIG_RPMSGMTD=y
 CONFIG_RPMSG_PING=y
+CONFIG_RPMSG_PORT_UART=y
 CONFIG_RPTUN=y
 CONFIG_RPTUN_IVSHMEM=y
 CONFIG_RPTUN_IVSHMEM_NAME="0:server:s"

boards/arm/qemu/qemu-armv7a/configs/rpserver_ivshmem/defconfig

@@ -44,6 +44,9 @@ CONFIG_DEBUG_SYMBOLS=y
 CONFIG_DEVICE_TREE=y
 CONFIG_DEV_RPMSG_SERVER=y
 CONFIG_DEV_SIMPLE_ADDRENV=y
+CONFIG_DRIVERS_VIRTIO=y
+CONFIG_DRIVERS_VIRTIO_MMIO=y
+CONFIG_DRIVERS_VIRTIO_SERIAL=y
 CONFIG_EXAMPLES_HELLO=y
 CONFIG_EXAMPLES_RPMSGSOCKET=y
 CONFIG_EXPERIMENTAL=y
@@ -86,6 +89,7 @@ CONFIG_RAW_BINARY=y
 CONFIG_READLINE_CMD_HISTORY=y
 CONFIG_READLINE_TABCOMPLETION=y
 CONFIG_RPMSG_PING=y
+CONFIG_RPMSG_PORT_UART=y
 CONFIG_RPTUN=y
 CONFIG_RPTUN_IVSHMEM=y
 CONFIG_RPTUN_IVSHMEM_NAME="0:proxy:m"

boards/arm/qemu/qemu-armv7a/src/qemu_bringup.c

@@ -31,6 +31,7 @@
 
 #include <nuttx/fs/fs.h>
 #include <nuttx/fdt.h>
+#include <nuttx/rpmsg/rpmsg_port.h>
 
 #ifdef CONFIG_LIBC_FDT
 #  include <libfdt.h>
@@ -97,6 +98,54 @@ static void register_devices_from_fdt(void)
 
 #endif
 
+/****************************************************************************
+ * Name: rpmsg_port_uart_init
+ ****************************************************************************/
+
+#ifdef CONFIG_RPMSG_PORT_UART
+static int rpmsg_port_uart_init(void)
+{
+  const char *remotecpu;
+  const char *localcpu;
+  int ret;
+
+  if (strcmp(CONFIG_LIBC_HOSTNAME, "server") == 0)
+    {
+      localcpu = "server2";
+      remotecpu = "proxy2";
+    }
+  else if (strcmp(CONFIG_LIBC_HOSTNAME, "proxy") == 0)
+    {
+      localcpu = "proxy2";
+      remotecpu = "server2";
+    }
+  else
+    {
+      syslog(LOG_ERR, "ERROR: hostname must be server or proxy, now: %s\n",
+             CONFIG_LIBC_HOSTNAME);
+      return -EINVAL;
+    }
+
+  const struct rpmsg_port_config_s cfg =
+    {
+      .remotecpu = remotecpu,
+      .txnum = 8,
+      .rxnum = 8,
+      .txlen = 2048,
+      .rxlen = 2048,
+    };
+
+  ret = rpmsg_port_uart_initialize(&cfg, "/dev/ttyV0", localcpu);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR,
+             "ERROR: Failed to initialize rpmsg port uart: %d\n", ret);
+    }
+
+  return ret;
+}
+#endif
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -148,6 +197,15 @@ int qemu_bringup(void)
     }
 #endif
 
+#ifdef CONFIG_RPMSG_PORT_UART
+  ret = rpmsg_port_uart_init();
+  if (ret < 0)
+    {
+      syslog(LOG_ERR,
+             "ERROR: Failed to initialize rpmsg port uart: %d\n", ret);
+    }
+#endif
+
   UNUSED(ret);
   return OK;
 }