added new metal sdk

1 files changed, 23 insertions, 0 deletions

diff --git a/code/fe310/gloss/sys_read.c b/code/fe310/gloss/sys_read.c
new file mode 100644
index 0000000..1857fc6
--- /dev/null
+++ b/code/fe310/gloss/sys_read.c
@@ -0,0 +1,23 @@
+#include <sys/types.h>
+#include <errno.h>
+#include <unistd.h>
+
+#include "platform.h"
+
+/* Read from a file.  */
+ssize_t
+_read(int fd, void *ptr, size_t len)
+{
+  if (fd != STDIN_FILENO) {
+    errno = ENOSYS;
+    return -1;
+  }
+
+  char *current = ptr;
+  for (size_t i = 0; i < len; i++) {
+    volatile uint32_t r;
+    while ((r = UART0_REG(UART_REG_RXFIFO)) & 0x80000000);
+    current[i] = r & 0xFF;
+  }
+  return len;
+}