1 files changed, 57 insertions, 0 deletions
diff --git a/core/drivers/ns16550.c b/core/drivers/ns16550.c
new file mode 100644
index 0000000..710b351
--- /dev/null
+++ b/core/drivers/ns16550.c
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2015 Freescale Semiconductor, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <drivers/ns16550.h>
+#include <io.h>
+
+/* uart register defines */
+#define UART_RBR	0x0
+#define UART_THR	0x0
+#define UART_IER	0x1
+#define UART_FCR	0x2
+#define UART_LCR	0x3
+#define UART_MCR	0x4
+#define UART_LSR	0x5
+#define UART_MSR	0x6
+#define UART_SPR	0x7
+
+/* uart status register bits */
+#define UART_LSR_THRE	0x20 /* Transmit-hold-register empty */
+
+void ns16550_flush(vaddr_t base)
+{
+	while ((read8(base + UART_LSR) & UART_LSR_THRE) == 0)
+		;
+}
+
+void ns16550_putc(int ch, vaddr_t base)
+{
+	ns16550_flush(base);
+
+	/* write out charset to Transmit-hold-register */
+	write8(ch, base + UART_THR);
+}