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-rw-r--r--arch/i386/cpu/serial.c506
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diff --git a/arch/i386/cpu/serial.c b/arch/i386/cpu/serial.c
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+/*
+ * (C) Copyright 2002
+ * Daniel Engström, Omicron Ceti AB, daniel@omicron.se
+ *
+ * (C) Copyright 2000
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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
+ */
+/*------------------------------------------------------------------------------+ */
+
+/*
+ * This source code is dual-licensed. You may use it under the terms of the
+ * GNU General Public License version 2, or under the license below.
+ *
+ * This source code has been made available to you by IBM on an AS-IS
+ * basis. Anyone receiving this source is licensed under IBM
+ * copyrights to use it in any way he or she deems fit, including
+ * copying it, modifying it, compiling it, and redistributing it either
+ * with or without modifications. No license under IBM patents or
+ * patent applications is to be implied by the copyright license.
+ *
+ * Any user of this software should understand that IBM cannot provide
+ * technical support for this software and will not be responsible for
+ * any consequences resulting from the use of this software.
+ *
+ * Any person who transfers this source code or any derivative work
+ * must include the IBM copyright notice, this paragraph, and the
+ * preceding two paragraphs in the transferred software.
+ *
+ * COPYRIGHT I B M CORPORATION 1995
+ * LICENSED MATERIAL - PROGRAM PROPERTY OF I B M
+ */
+/*------------------------------------------------------------------------------- */
+
+#include <common.h>
+#include <watchdog.h>
+#include <asm/io.h>
+#include <asm/ibmpc.h>
+
+#ifdef CONFIG_SERIAL_SOFTWARE_FIFO
+#include <malloc.h>
+#endif
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define UART_RBR 0x00
+#define UART_THR 0x00
+#define UART_IER 0x01
+#define UART_IIR 0x02
+#define UART_FCR 0x02
+#define UART_LCR 0x03
+#define UART_MCR 0x04
+#define UART_LSR 0x05
+#define UART_MSR 0x06
+#define UART_SCR 0x07
+#define UART_DLL 0x00
+#define UART_DLM 0x01
+
+/*-----------------------------------------------------------------------------+
+ | Line Status Register.
+ +-----------------------------------------------------------------------------*/
+#define asyncLSRDataReady1 0x01
+#define asyncLSROverrunError1 0x02
+#define asyncLSRParityError1 0x04
+#define asyncLSRFramingError1 0x08
+#define asyncLSRBreakInterrupt1 0x10
+#define asyncLSRTxHoldEmpty1 0x20
+#define asyncLSRTxShiftEmpty1 0x40
+#define asyncLSRRxFifoError1 0x80
+
+
+#ifdef CONFIG_SERIAL_SOFTWARE_FIFO
+/*-----------------------------------------------------------------------------+
+ | Fifo
+ +-----------------------------------------------------------------------------*/
+typedef struct {
+ char *rx_buffer;
+ ulong rx_put;
+ ulong rx_get;
+ int cts;
+} serial_buffer_t;
+
+volatile serial_buffer_t buf_info;
+static int serial_buffer_active=0;
+#endif
+
+
+static int serial_div(int baudrate)
+{
+
+ switch (baudrate) {
+ case 1200:
+ return 96;
+ case 9600:
+ return 12;
+ case 19200:
+ return 6;
+ case 38400:
+ return 3;
+ case 57600:
+ return 2;
+ case 115200:
+ return 1;
+ }
+
+ return 12;
+}
+
+
+/*
+ * Minimal serial functions needed to use one of the SMC ports
+ * as serial console interface.
+ */
+
+int serial_init(void)
+{
+ volatile char val;
+ int bdiv = serial_div(gd->baudrate);
+
+ outb(0x80, UART0_BASE + UART_LCR); /* set DLAB bit */
+ outb(bdiv, UART0_BASE + UART_DLL); /* set baudrate divisor */
+ outb(bdiv >> 8, UART0_BASE + UART_DLM);/* set baudrate divisor */
+ outb(0x03, UART0_BASE + UART_LCR); /* clear DLAB; set 8 bits, no parity */
+ outb(0x01, UART0_BASE + UART_FCR); /* enable FIFO */
+ outb(0x0b, UART0_BASE + UART_MCR); /* Set DTR and RTS active */
+ val = inb(UART0_BASE + UART_LSR); /* clear line status */
+ val = inb(UART0_BASE + UART_RBR); /* read receive buffer */
+ outb(0x00, UART0_BASE + UART_SCR); /* set scratchpad */
+ outb(0x00, UART0_BASE + UART_IER); /* set interrupt enable reg */
+
+ return 0;
+}
+
+
+void serial_setbrg(void)
+{
+ unsigned short bdiv;
+
+ bdiv = serial_div(gd->baudrate);
+
+ outb(0x80, UART0_BASE + UART_LCR); /* set DLAB bit */
+ outb(bdiv&0xff, UART0_BASE + UART_DLL); /* set baudrate divisor */
+ outb(bdiv >> 8, UART0_BASE + UART_DLM);/* set baudrate divisor */
+ outb(0x03, UART0_BASE + UART_LCR); /* clear DLAB; set 8 bits, no parity */
+}
+
+
+void serial_putc(const char c)
+{
+ int i;
+
+ if (c == '\n')
+ serial_putc ('\r');
+
+ /* check THRE bit, wait for transmiter available */
+ for (i = 1; i < 3500; i++) {
+ if ((inb (UART0_BASE + UART_LSR) & 0x20) == 0x20) {
+ break;
+ }
+ udelay(100);
+ }
+ outb(c, UART0_BASE + UART_THR); /* put character out */
+}
+
+
+void serial_puts(const char *s)
+{
+ while (*s) {
+ serial_putc(*s++);
+ }
+}
+
+
+int serial_getc(void)
+{
+ unsigned char status = 0;
+
+#ifdef CONFIG_SERIAL_SOFTWARE_FIFO
+ if (serial_buffer_active) {
+ return serial_buffered_getc();
+ }
+#endif
+
+ while (1) {
+#if defined(CONFIG_HW_WATCHDOG)
+ WATCHDOG_RESET(); /* Reset HW Watchdog, if needed */
+#endif /* CONFIG_HW_WATCHDOG */
+ status = inb(UART0_BASE + UART_LSR);
+ if ((status & asyncLSRDataReady1) != 0x0) {
+ break;
+ }
+ if ((status & ( asyncLSRFramingError1 |
+ asyncLSROverrunError1 |
+ asyncLSRParityError1 |
+ asyncLSRBreakInterrupt1 )) != 0) {
+ outb(asyncLSRFramingError1 |
+ asyncLSROverrunError1 |
+ asyncLSRParityError1 |
+ asyncLSRBreakInterrupt1, UART0_BASE + UART_LSR);
+ }
+ }
+ return (0x000000ff & (int) inb (UART0_BASE));
+}
+
+
+int serial_tstc(void)
+{
+ unsigned char status;
+
+#ifdef CONFIG_SERIAL_SOFTWARE_FIFO
+ if (serial_buffer_active) {
+ return serial_buffered_tstc();
+ }
+#endif
+
+ status = inb(UART0_BASE + UART_LSR);
+ if ((status & asyncLSRDataReady1) != 0x0) {
+ return (1);
+ }
+ if ((status & ( asyncLSRFramingError1 |
+ asyncLSROverrunError1 |
+ asyncLSRParityError1 |
+ asyncLSRBreakInterrupt1 )) != 0) {
+ outb(asyncLSRFramingError1 |
+ asyncLSROverrunError1 |
+ asyncLSRParityError1 |
+ asyncLSRBreakInterrupt1, UART0_BASE + UART_LSR);
+ }
+ return 0;
+}
+
+
+#ifdef CONFIG_SERIAL_SOFTWARE_FIFO
+
+void serial_isr(void *arg)
+{
+ int space;
+ int c;
+ int rx_put = buf_info.rx_put;
+
+ if (buf_info.rx_get <= rx_put) {
+ space = CONFIG_SERIAL_SOFTWARE_FIFO - (rx_put - buf_info.rx_get);
+ } else {
+ space = buf_info.rx_get - rx_put;
+ }
+
+ while (inb(UART0_BASE + UART_LSR) & 1) {
+ c = inb(UART0_BASE);
+ if (space) {
+ buf_info.rx_buffer[rx_put++] = c;
+ space--;
+
+ if (rx_put == buf_info.rx_get) {
+ buf_info.rx_get++;
+ if (rx_put == CONFIG_SERIAL_SOFTWARE_FIFO) {
+ buf_info.rx_get = 0;
+ }
+ }
+
+ if (rx_put == CONFIG_SERIAL_SOFTWARE_FIFO) {
+ rx_put = 0;
+ if (0 == buf_info.rx_get) {
+ buf_info.rx_get = 1;
+ }
+
+ }
+
+ }
+ if (space < CONFIG_SERIAL_SOFTWARE_FIFO / 4) {
+ /* Stop flow by setting RTS inactive */
+ outb(inb(UART0_BASE + UART_MCR) & (0xFF ^ 0x02),
+ UART0_BASE + UART_MCR);
+ }
+ }
+ buf_info.rx_put = rx_put;
+}
+
+void serial_buffered_init(void)
+{
+ serial_puts ("Switching to interrupt driven serial input mode.\n");
+ buf_info.rx_buffer = malloc (CONFIG_SERIAL_SOFTWARE_FIFO);
+ buf_info.rx_put = 0;
+ buf_info.rx_get = 0;
+
+ if (inb (UART0_BASE + UART_MSR) & 0x10) {
+ serial_puts ("Check CTS signal present on serial port: OK.\n");
+ buf_info.cts = 1;
+ } else {
+ serial_puts ("WARNING: CTS signal not present on serial port.\n");
+ buf_info.cts = 0;
+ }
+
+ irq_install_handler ( VECNUM_U0 /*UART0 */ /*int vec */ ,
+ serial_isr /*interrupt_handler_t *handler */ ,
+ (void *) &buf_info /*void *arg */ );
+
+ /* Enable "RX Data Available" Interrupt on UART */
+ /* outb(inb(UART0_BASE + UART_IER) |0x01, UART0_BASE + UART_IER); */
+ outb(0x01, UART0_BASE + UART_IER);
+
+ /* Set DTR and RTS active, enable interrupts */
+ outb(inb (UART0_BASE + UART_MCR) | 0x0b, UART0_BASE + UART_MCR);
+
+ /* Setup UART FIFO: RX trigger level: 1 byte, Enable FIFO */
+ outb( /*(1 << 6) |*/ 1, UART0_BASE + UART_FCR);
+
+ serial_buffer_active = 1;
+}
+
+void serial_buffered_putc (const char c)
+{
+ int i;
+ /* Wait for CTS */
+#if defined(CONFIG_HW_WATCHDOG)
+ while (!(inb (UART0_BASE + UART_MSR) & 0x10))
+ WATCHDOG_RESET ();
+#else
+ if (buf_info.cts) {
+ for (i=0;i<1000;i++) {
+ if ((inb (UART0_BASE + UART_MSR) & 0x10)) {
+ break;
+ }
+ }
+ if (i!=1000) {
+ buf_info.cts = 0;
+ }
+ } else {
+ if ((inb (UART0_BASE + UART_MSR) & 0x10)) {
+ buf_info.cts = 1;
+ }
+ }
+
+#endif
+ serial_putc (c);
+}
+
+void serial_buffered_puts(const char *s)
+{
+ serial_puts (s);
+}
+
+int serial_buffered_getc(void)
+{
+ int space;
+ int c;
+ int rx_get = buf_info.rx_get;
+ int rx_put;
+
+#if defined(CONFIG_HW_WATCHDOG)
+ while (rx_get == buf_info.rx_put)
+ WATCHDOG_RESET ();
+#else
+ while (rx_get == buf_info.rx_put);
+#endif
+ c = buf_info.rx_buffer[rx_get++];
+ if (rx_get == CONFIG_SERIAL_SOFTWARE_FIFO) {
+ rx_get = 0;
+ }
+ buf_info.rx_get = rx_get;
+
+ rx_put = buf_info.rx_put;
+ if (rx_get <= rx_put) {
+ space = CONFIG_SERIAL_SOFTWARE_FIFO - (rx_put - rx_get);
+ } else {
+ space = rx_get - rx_put;
+ }
+ if (space > CONFIG_SERIAL_SOFTWARE_FIFO / 2) {
+ /* Start flow by setting RTS active */
+ outb(inb (UART0_BASE + UART_MCR) | 0x02, UART0_BASE + UART_MCR);
+ }
+
+ return c;
+}
+
+int serial_buffered_tstc(void)
+{
+ return (buf_info.rx_get != buf_info.rx_put) ? 1 : 0;
+}
+
+#endif /* CONFIG_SERIAL_SOFTWARE_FIFO */
+
+
+#if defined(CONFIG_CMD_KGDB)
+/*
+ AS HARNOIS : according to CONFIG_KGDB_SER_INDEX kgdb uses serial port
+ number 0 or number 1
+ - if CONFIG_KGDB_SER_INDEX = 1 => serial port number 0 :
+ configuration has been already done
+ - if CONFIG_KGDB_SER_INDEX = 2 => serial port number 1 :
+ configure port 1 for serial I/O with rate = CONFIG_KGDB_BAUDRATE
+*/
+#if (CONFIG_KGDB_SER_INDEX & 2)
+void kgdb_serial_init(void)
+{
+ volatile char val;
+ bdiv = serial_div (CONFIG_KGDB_BAUDRATE);
+
+ /*
+ * Init onboard 16550 UART
+ */
+ outb(0x80, UART1_BASE + UART_LCR); /* set DLAB bit */
+ outb((bdiv & 0xff), UART1_BASE + UART_DLL); /* set divisor for 9600 baud */
+ outb((bdiv >> 8 ), UART1_BASE + UART_DLM); /* set divisor for 9600 baud */
+ outb(0x03, UART1_BASE + UART_LCR); /* line control 8 bits no parity */
+ outb(0x00, UART1_BASE + UART_FCR); /* disable FIFO */
+ outb(0x00, UART1_BASE + UART_MCR); /* no modem control DTR RTS */
+ val = inb(UART1_BASE + UART_LSR); /* clear line status */
+ val = inb(UART1_BASE + UART_RBR); /* read receive buffer */
+ outb(0x00, UART1_BASE + UART_SCR); /* set scratchpad */
+ outb(0x00, UART1_BASE + UART_IER); /* set interrupt enable reg */
+}
+
+
+void putDebugChar(const char c)
+{
+ if (c == '\n')
+ serial_putc ('\r');
+
+ outb(c, UART1_BASE + UART_THR); /* put character out */
+
+ /* check THRE bit, wait for transfer done */
+ while ((inb(UART1_BASE + UART_LSR) & 0x20) != 0x20);
+}
+
+
+void putDebugStr(const char *s)
+{
+ while (*s) {
+ serial_putc(*s++);
+ }
+}
+
+
+int getDebugChar(void)
+{
+ unsigned char status = 0;
+
+ while (1) {
+ status = inb(UART1_BASE + UART_LSR);
+ if ((status & asyncLSRDataReady1) != 0x0) {
+ break;
+ }
+ if ((status & ( asyncLSRFramingError1 |
+ asyncLSROverrunError1 |
+ asyncLSRParityError1 |
+ asyncLSRBreakInterrupt1 )) != 0) {
+ outb(asyncLSRFramingError1 |
+ asyncLSROverrunError1 |
+ asyncLSRParityError1 |
+ asyncLSRBreakInterrupt1, UART1_BASE + UART_LSR);
+ }
+ }
+ return (0x000000ff & (int) inb(UART1_BASE));
+}
+
+
+void kgdb_interruptible(int yes)
+{
+ return;
+}
+
+#else /* ! (CONFIG_KGDB_SER_INDEX & 2) */
+
+void kgdb_serial_init(void)
+{
+ serial_printf ("[on serial] ");
+}
+
+void putDebugChar(int c)
+{
+ serial_putc (c);
+}
+
+void putDebugStr(const char *str)
+{
+ serial_puts (str);
+}
+
+int getDebugChar(void)
+{
+ return serial_getc ();
+}
+
+void kgdb_interruptible(int yes)
+{
+ return;
+}
+#endif /* (CONFIG_KGDB_SER_INDEX & 2) */
+#endif
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