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Diffstat (limited to 'target/image/generic/lzma-loader/src/uart16550.c')
-rw-r--r--target/image/generic/lzma-loader/src/uart16550.c86
1 files changed, 86 insertions, 0 deletions
diff --git a/target/image/generic/lzma-loader/src/uart16550.c b/target/image/generic/lzma-loader/src/uart16550.c
new file mode 100644
index 0000000..7df5727
--- /dev/null
+++ b/target/image/generic/lzma-loader/src/uart16550.c
@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2001 MontaVista Software Inc.
+ * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ */
+
+
+#include "uart16550.h"
+
+/* === CONFIG === */
+
+#define BASE 0xb8058000
+#define MAX_BAUD 1152000
+#define REG_OFFSET 4
+
+/* === END OF CONFIG === */
+
+/* register offset */
+#define OFS_RCV_BUFFER (0*REG_OFFSET)
+#define OFS_TRANS_HOLD (0*REG_OFFSET)
+#define OFS_SEND_BUFFER (0*REG_OFFSET)
+#define OFS_INTR_ENABLE (1*REG_OFFSET)
+#define OFS_INTR_ID (2*REG_OFFSET)
+#define OFS_DATA_FORMAT (3*REG_OFFSET)
+#define OFS_LINE_CONTROL (3*REG_OFFSET)
+#define OFS_MODEM_CONTROL (4*REG_OFFSET)
+#define OFS_RS232_OUTPUT (4*REG_OFFSET)
+#define OFS_LINE_STATUS (5*REG_OFFSET)
+#define OFS_MODEM_STATUS (6*REG_OFFSET)
+#define OFS_RS232_INPUT (6*REG_OFFSET)
+#define OFS_SCRATCH_PAD (7*REG_OFFSET)
+
+#define OFS_DIVISOR_LSB (0*REG_OFFSET)
+#define OFS_DIVISOR_MSB (1*REG_OFFSET)
+
+
+/* memory-mapped read/write of the port */
+#define UART16550_READ(y) (*((volatile uint32*)(BASE + y)))
+#define UART16550_WRITE(y, z) ((*((volatile uint32*)(BASE + y))) = z)
+
+#define DEBUG_LED (*(unsigned short*)0xb7ffffc0)
+#define OutputLED(x) (DEBUG_LED = x)
+
+void Uart16550Init(uint32 baud, uint8 data, uint8 parity, uint8 stop)
+{
+ /* disable interrupts */
+ UART16550_WRITE(OFS_INTR_ENABLE, 0);
+
+ /* set up buad rate */
+ {
+ uint32 divisor;
+
+ /* set DIAB bit */
+ UART16550_WRITE(OFS_LINE_CONTROL, 0x80);
+
+ /* set divisor */
+ divisor = MAX_BAUD / baud;
+ UART16550_WRITE(OFS_DIVISOR_LSB, divisor & 0xff);
+ UART16550_WRITE(OFS_DIVISOR_MSB, (divisor & 0xff00)>>8);
+
+ /* clear DIAB bit */
+ UART16550_WRITE(OFS_LINE_CONTROL, 0x0);
+ }
+
+ /* set data format */
+ UART16550_WRITE(OFS_DATA_FORMAT, data | parity | stop);
+}
+
+uint8 Uart16550GetPoll()
+{
+ while((UART16550_READ(OFS_LINE_STATUS) & 0x1) == 0);
+ return UART16550_READ(OFS_RCV_BUFFER);
+}
+
+
+void Uart16550Put(uint8 byte)
+{
+ while ((UART16550_READ(OFS_LINE_STATUS) &0x20) == 0);
+ UART16550_WRITE(OFS_SEND_BUFFER, byte);
+}
+