adds RISCV-VP platform

env/riscv_vp/bsp_read.c

@@ -0,0 +1,21 @@
+#include "platform.h"
+#include <stdint.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+ssize_t _bsp_read(int fd, void *ptr, size_t len) {
+  uint8_t *current = (uint8_t *)ptr;
+  ssize_t result = 0;
+  if (isatty(fd)) {
+    for (current = (uint8_t *)ptr; (current < ((uint8_t *)ptr) + len) &&
+                                   (get_uart_rx_tx_reg_rx_avail(uart) > 0);
+         current++) {
+      *current = uart_read(uart);
+      result++;
+    }
+
+    return result;
+  }
+  return EOF;
+}