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authorwdenk <wdenk>2004-07-01 16:30:44 +0000
committerwdenk <wdenk>2004-07-01 16:30:44 +0000
commit39539887ea7dc298c98ac1fddd38551dfa335120 (patch)
tree31e3bc0bd93cead0c977b8fd26ede7d06f70e0a1 /drivers/s3c4510b_uart.c
parente94d2cd9d1dc0f58b18e7c31fc9345129b1a44fb (diff)
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* Code cleanup (ARM mostly)
* Patch by Curt Brune, 17 May 2004: - Add support for Samsung S3C4510B CPU (ARM7tdmi based SoC) - Add support for ESPD-Inc. EVB4510 Board
Diffstat (limited to 'drivers/s3c4510b_uart.c')
-rw-r--r--drivers/s3c4510b_uart.c216
1 files changed, 216 insertions, 0 deletions
diff --git a/drivers/s3c4510b_uart.c b/drivers/s3c4510b_uart.c
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+++ b/drivers/s3c4510b_uart.c
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+/*
+ * Copyright (c) 2004 Cucy Systems (http://www.cucy.com)
+ * Curt Brune <curt@cucy.com>
+ *
+ * (C) Copyright 2004
+ * DAVE Srl
+ * http://www.dave-tech.it
+ * http://www.wawnet.biz
+ * mailto:info@wawnet.biz
+ *
+ * (C) Copyright 2002-2004
+ * Wolfgang Denk, DENX Software Engineering, <wd@denx.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu@sysgo.de>
+ *
+ * Copyright (C) 1999 2000 2001 Erik Mouw (J.A.K.Mouw@its.tudelft.nl)
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * MODULE: $Id:$
+ * Description: UART/Serial interface for Samsung S3C4510B SoC
+ * Runtime Env: ARM7TDMI
+ * Change History:
+ * 03-02-04 Create (Curt Brune) curt@cucy.com
+ *
+ */
+
+#include <common.h>
+
+#ifdef CONFIG_DRIVER_S3C4510_UART
+
+#include <asm/hardware.h>
+#include "s3c4510b_uart.h"
+
+static UART *uart;
+
+/* flush serial input queue. returns 0 on success or negative error
+ * number otherwise
+ */
+static int serial_flush_input(void)
+{
+ volatile u32 tmp;
+
+ /* keep on reading as long as the receiver is not empty */
+ while( uart->m_stat.bf.rxReady) {
+ tmp = uart->m_rx;
+ }
+
+ return 0;
+}
+
+
+/* flush output queue. returns 0 on success or negative error number
+ * otherwise
+ */
+static int serial_flush_output(void)
+{
+ /* wait until the transmitter is no longer busy */
+ while( !uart->m_stat.bf.txBufEmpty);
+
+ return 0;
+}
+
+
+void serial_setbrg (void)
+{
+ DECLARE_GLOBAL_DATA_PTR;
+
+ UART_LINE_CTRL ulctrl;
+ UART_CTRL uctrl;
+ UART_BAUD_DIV ubd;
+
+ serial_flush_output();
+ serial_flush_input();
+
+ /* control register */
+ uctrl.ui = 0x0;
+ uctrl.bf.rxMode = 0x1;
+ uctrl.bf.rxIrq = 0x0;
+ uctrl.bf.txMode = 0x1;
+ uctrl.bf.DSR = 0x0;
+ uctrl.bf.sendBreak = 0x0;
+ uctrl.bf.loopBack = 0x0;
+ uart->m_ctrl.ui = uctrl.ui;
+
+ /* line control register */
+ ulctrl.ui = 0x0;
+ ulctrl.bf.wordLen = 0x3; /* 8 bit data */
+ ulctrl.bf.nStop = 0x0; /* 1 stop bit */
+ ulctrl.bf.parity = 0x0; /* no parity */
+ ulctrl.bf.clk = 0x0; /* internal clock */
+ ulctrl.bf.infra_red = 0x0; /* no infra_red */
+ uart->m_lineCtrl.ui = ulctrl.ui;
+
+ ubd.ui = 0x0;
+
+ /* see table on page 10-15 in SAMSUNG S3C4510B manual */
+ /* get correct divisor */
+ switch(gd->baudrate) {
+ case 1200: ubd.bf.cnt0 = 1301; break;
+ case 2400: ubd.bf.cnt0 = 650; break;
+ case 4800: ubd.bf.cnt0 = 324; break;
+ case 9600: ubd.bf.cnt0 = 162; break;
+ case 19200: ubd.bf.cnt0 = 80; break;
+ case 38400: ubd.bf.cnt0 = 40; break;
+ case 57600: ubd.bf.cnt0 = 26; break;
+ case 115200: ubd.bf.cnt0 = 13; break;
+ }
+
+ uart->m_baudDiv.ui = ubd.ui;
+ uart->m_baudCnt = 0x0;
+ uart->m_baudClk = 0x0;
+
+}
+
+
+/*
+ * Initialise the serial port with the given baudrate. The settings
+ * are always 8 data bits, no parity, 1 stop bit, no start bits.
+ *
+ */
+int serial_init (void)
+{
+
+#if CONFIG_SERIAL1 == 1
+ uart = (UART *)UART0_BASE;
+#elif CONFIG_SERIAL1 == 2
+ uart = (UART *)UART1_BASE;
+#else
+#error CONFIG_SERIAL1 not equal to 1 or 2
+#endif
+
+ serial_setbrg ();
+
+ return (0);
+}
+
+
+/*
+ * Output a single byte to the serial port.
+ */
+void serial_putc (const char c)
+{
+ /* wait for room in the transmit FIFO */
+ while( !uart->m_stat.bf.txBufEmpty);
+
+ uart->m_tx = c;
+
+ /*
+ to be polite with serial console add a line feed
+ to the carriage return character
+ */
+ if (c=='\n')
+ serial_putc('\r');
+}
+
+/*
+ * Test if an input byte is ready from the serial port. Returns non-zero on
+ * success, 0 otherwise.
+ */
+int serial_tstc (void)
+{
+ return uart->m_stat.bf.rxReady;
+}
+
+/*
+ * Read a single byte from the serial port. Returns 1 on success, 0
+ * otherwise. When the function is succesfull, the character read is
+ * written into its argument c.
+ */
+int serial_getc (void)
+{
+ int rv;
+
+ for(;;) {
+ rv = serial_tstc();
+
+ if (rv) {
+ return uart->m_rx & 0xFF;
+ }
+ }
+}
+
+void serial_puts (const char *s)
+{
+ while (*s) {
+ serial_putc (*s++);
+ }
+
+ /* busy wait for tx complete */
+ while ( !uart->m_stat.bf.txComplete);
+
+ /* clear break */
+ uart->m_ctrl.bf.sendBreak = 0;
+
+}
+
+#endif