Initial revision

1 files changed, 56 insertions, 0 deletions

diff --git a/drivers/ns16550.c b/drivers/ns16550.c
new file mode 100644
index 0000000..6f818d7
--- /dev/null
+++ b/drivers/ns16550.c
@@ -0,0 +1,56 @@
+/*
+ * COM1 NS16550 support
+ * originally from linux source (arch/ppc/boot/ns16550.c)
+ * modified to use CFG_ISA_MEM and new defines
+ */
+
+#include <config.h>
+
+#ifdef CFG_NS16550
+
+#include <ns16550.h>
+
+#define LCRVAL LCR_8N1					/* 8 data, 1 stop, no parity */
+#define MCRVAL (MCR_DTR | MCR_RTS)			/* RTS/DTR */
+#define FCRVAL (FCR_FIFO_EN | FCR_RXSR | FCR_TXSR)	/* Clear & enable FIFOs */
+
+void NS16550_init (NS16550_t com_port, int baud_divisor)
+{
+	com_port->ier = 0x00;
+	com_port->lcr = LCR_BKSE | LCRVAL;
+	com_port->dll = baud_divisor & 0xff;
+	com_port->dlm = (baud_divisor >> 8) & 0xff;
+	com_port->lcr = LCRVAL;
+	com_port->mcr = MCRVAL;
+	com_port->fcr = FCRVAL;
+}
+
+void NS16550_reinit (NS16550_t com_port, int baud_divisor)
+{
+	com_port->ier = 0x00;
+	com_port->lcr = LCR_BKSE;
+	com_port->dll = baud_divisor & 0xff;
+	com_port->dlm = (baud_divisor >> 8) & 0xff;
+	com_port->lcr = LCRVAL;
+	com_port->mcr = MCRVAL;
+	com_port->fcr = FCRVAL;
+}
+
+void NS16550_putc (NS16550_t com_port, char c)
+{
+	while ((com_port->lsr & LSR_THRE) == 0);
+	com_port->thr = c;
+}
+
+char NS16550_getc (NS16550_t com_port)
+{
+	while ((com_port->lsr & LSR_DR) == 0);
+	return (com_port->rbr);
+}
+
+int NS16550_tstc (NS16550_t com_port)
+{
+	return ((com_port->lsr & LSR_DR) != 0);
+}
+
+#endif