patch-2.4.19 linux-2.4.19/arch/mips/galileo-boards/ev64120/serialGT.c

• Lines: 213
• Date: Fri Aug 2 17:39:43 2002
• Orig file: linux-2.4.18/arch/mips/galileo-boards/ev64120/serialGT.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.18/arch/mips/galileo-boards/ev64120/serialGT.c linux-2.4.19/arch/mips/galileo-boards/ev64120/serialGT.c
@@ -0,0 +1,212 @@
+/*
+ * serialGT.c
+ *
+ * BRIEF MODULE DESCRIPTION
+ *  Low Level Serial Port control for use
+ *  with the Galileo EVB64120A MIPS eval board and 
+ *  its on board two channel 16552 Uart.
+ *
+ * Copyright (C) 2000 RidgeRun, Inc.
+ * Author: RidgeRun, Inc.
+ *   glonnon@ridgerun.com, skranz@ridgerun.com, stevej@ridgerun.com
+ *
+ *  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  SOFTWARE  IS PROVIDED   ``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 AUTHOR  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.
+ *
+ *  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.,
+ *  675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+// Note:
+//   Serial CHANNELS - 0 is the bottom connector of evb64120A.
+//                       (The one that maps to the "B" channel of the
+//                       board's uart)
+//                     1 is the top connector of evb64120A.
+//                       (The one that maps to the "A" channel of the
+//                       board's uart)
+int DEBUG_CHANNEL = 0;		// See Note Above
+int CONSOLE_CHANNEL = 1;	// See Note Above
+
+#define DUART 0xBD000000	/* Base address of Uart. */
+#define CHANNELOFFSET 0x20	/* DUART+CHANNELOFFSET gets you to the ChanA
+				   register set of the 16552 Uart device.
+				   DUART+0 gets you to the ChanB register set.
+				 */
+#define DUART_DELTA 0x4
+#define FIFO_ENABLE 0x07
+#define INT_ENABLE  0x04	/* default interrupt mask */
+
+#define RBR 0x00
+#define THR 0x00
+#define DLL 0x00
+#define IER 0x01
+#define DLM 0x01
+#define IIR 0x02
+#define FCR 0x02
+#define LCR 0x03
+#define MCR 0x04
+#define LSR 0x05
+#define MSR 0x06
+#define SCR 0x07
+
+#define LCR_DLAB 0x80
+#define XTAL 1843200
+#define LSR_THRE 0x20
+#define LSR_BI   0x10
+#define LSR_DR   0x01
+#define MCR_LOOP 0x10
+#define ACCESS_DELAY 0x10000
+
+/******************************
+ Routine:
+ Description:
+ ******************************/
+int inreg(int channel, int reg)
+{
+	int val;
+	val =
+	    *((volatile unsigned char *) DUART +
+	      (channel * CHANNELOFFSET) + (reg * DUART_DELTA));
+	return val;
+}
+
+/******************************
+ Routine:
+ Description:
+ ******************************/
+void outreg(int channel, int reg, unsigned char val)
+{
+	*((volatile unsigned char *) DUART + (channel * CHANNELOFFSET)
+	  + (reg * DUART_DELTA)) = val;
+}
+
+/******************************
+ Routine:
+ Description:
+   Initialize the device driver.
+ ******************************/
+void serial_init(int channel)
+{
+	/*
+	 * Configure active port, (CHANNELOFFSET already set.)
+	 *
+	 * Set 8 bits, 1 stop bit, no parity.
+	 *
+	 * LCR<7>       0       divisor latch access bit
+	 * LCR<6>       0       break control (1=send break)
+	 * LCR<5>       0       stick parity (0=space, 1=mark)
+	 * LCR<4>       0       parity even (0=odd, 1=even)
+	 * LCR<3>       0       parity enable (1=enabled)
+	 * LCR<2>       0       # stop bits (0=1, 1=1.5)
+	 * LCR<1:0>     11      bits per character(00=5, 01=6, 10=7, 11=8)
+	 */
+	outreg(channel, LCR, 0x3);
+
+	outreg(channel, FCR, FIFO_ENABLE);	/* Enable the FIFO */
+
+	outreg(channel, IER, INT_ENABLE);	/* Enable appropriate interrupts */
+}
+
+/******************************
+ Routine:
+ Description:
+   Set the baud rate.
+ ******************************/
+void serial_set(int channel, unsigned long baud)
+{
+	unsigned char sav_lcr;
+
+	/*
+	 * Enable access to the divisor latches by setting DLAB in LCR.
+	 *
+	 */
+	sav_lcr = inreg(channel, LCR);
+
+#if 0
+	/*
+	 * Set baud rate 
+	 */
+	outreg(channel, LCR, LCR_DLAB | sav_lcr);
+	//  outreg(DLL,(XTAL/(16*2*(baud))-2));
+	outreg(channel, DLL, XTAL / (16 * baud));
+	//  outreg(DLM,(XTAL/(16*2*(baud))-2)>>8);
+	outreg(channel, DLM, (XTAL / (16 * baud)) >> 8);
+#else
+	/*
+	 * Note: Set baud rate, hardcoded here for rate of 115200
+	 * since became unsure of above "buad rate" algorithm (??). 
+	 */
+	outreg(channel, LCR, 0x83);
+	outreg(channel, DLM, 0x00);	// See note above
+	outreg(channel, DLL, 0x02);	// See note above.
+	outreg(channel, LCR, 0x03);
+#endif
+
+	/*
+	 * Restore line control register
+	 */
+	outreg(channel, LCR, sav_lcr);
+}
+
+
+/******************************
+ Routine:
+ Description:
+   Transmit a character.
+ ******************************/
+void serial_putc(int channel, int c)
+{
+	while ((inreg(channel, LSR) & LSR_THRE) == 0);
+	outreg(channel, THR, c);
+}
+
+/******************************
+ Routine:
+ Description:
+    Read a received character if one is
+    available.  Return -1 otherwise.
+ ******************************/
+int serial_getc(int channel)
+{
+	if (inreg(channel, LSR) & LSR_DR) {
+		return inreg(channel, RBR);
+	}
+	return -1;
+}
+
+/******************************
+ Routine:
+ Description:
+   Used by embedded gdb client. (example; gdb-stub.c)
+ ******************************/
+char getDebugChar()
+{
+	int val;
+	while ((val = serial_getc(DEBUG_CHANNEL)) == -1);	// loop until we get a character in.
+	return (char) val;
+}
+
+/******************************
+ Routine:
+ Description:
+   Used by embedded gdb target. (example; gdb-stub.c)
+ ******************************/
+void putDebugChar(char c)
+{
+	serial_putc(DEBUG_CHANNEL, (int) c);
+}