arch/powerpc/boot/serial.c

   1 /*
   2  * Generic serial console support
   3  *
   4  * Author: Mark A. Greer <mgreer@mvista.com>
   5  *
   6  * Code in serial_edit_cmdline() copied from <file:arch/ppc/boot/simple/misc.c>
   7  * and was written by Matt Porter <mporter@kernel.crashing.org>.
   8  *
   9  * 2001,2006 (c) MontaVista Software, Inc.  This file is licensed under
  10  * the terms of the GNU General Public License version 2.  This program
  11  * is licensed "as is" without any warranty of any kind, whether express
  12  * or implied.
  13  */
  14 #include <stdarg.h>
  15 #include <stddef.h>
  16 #include "types.h"
  17 #include "string.h"
  18 #include "stdio.h"
  19 #include "io.h"
  20 #include "ops.h"
  21
  22 static int serial_open(void)
  23 {
  24         struct serial_console_data *scdp = console_ops.data;
  25         return scdp->open();
  26 }
  27
  28 static void serial_write(const char *buf, int len)
  29 {
  30         struct serial_console_data *scdp = console_ops.data;
  31
  32         while (*buf != '\0')
  33                 scdp->putc(*buf++);
  34 }
  35
  36 static void serial_edit_cmdline(char *buf, int len)
  37 {
  38         int timer = 0, count;
  39         char ch, *cp;
  40         struct serial_console_data *scdp = console_ops.data;
  41
  42         cp = buf;
  43         count = strlen(buf);
  44         cp = &buf[count];
  45         count++;
  46
  47         while (timer++ < 5*1000) {
  48                 if (scdp->tstc()) {
  49                         while (((ch = scdp->getc()) != '\n') && (ch != '\r')) {
  50                                 /* Test for backspace/delete */
  51                                 if ((ch == '\b') || (ch == '\177')) {
  52                                         if (cp != buf) {
  53                                                 cp--;
  54                                                 count--;
  55                                                 printf("\b \b");
  56                                         }
  57                                 /* Test for ^x/^u (and wipe the line) */
  58                                 } else if ((ch == '\030') || (ch == '\025')) {
  59                                         while (cp != buf) {
  60                                                 cp--;
  61                                                 count--;
  62                                                 printf("\b \b");
  63                                         }
  64                                 } else if (count < len) {
  65                                                 *cp++ = ch;
  66                                                 count++;
  67                                                 scdp->putc(ch);
  68                                 }
  69                         }
  70                         break;  /* Exit 'timer' loop */
  71                 }
  72                 udelay(1000);  /* 1 msec */
  73         }
  74         *cp = 0;
  75 }
  76
  77 static void serial_close(void)
  78 {
  79         struct serial_console_data *scdp = console_ops.data;
  80
  81         if (scdp->close)
  82                 scdp->close();
  83 }
  84
  85 static void *serial_get_stdout_devp(void)
  86 {
  87         void *devp;
  88         char devtype[MAX_PROP_LEN];
  89         char path[MAX_PATH_LEN];
  90
  91         devp = finddevice("/chosen");
  92         if (devp == NULL)
  93                 goto err_out;
  94
  95         if (getprop(devp, "linux,stdout-path", path, MAX_PATH_LEN) > 0) {
  96                 devp = finddevice(path);
  97                 if (devp == NULL)
  98                         goto err_out;
  99
 100                 if ((getprop(devp, "device_type", devtype, sizeof(devtype)) > 0)
 101                                 && !strcmp(devtype, "serial"))
 102                         return devp;
 103         }
 104 err_out:
 105         return NULL;
 106 }
 107
 108 static struct serial_console_data serial_cd;
 109
 110 /* Node's "compatible" property determines which serial driver to use */
 111 int serial_console_init(void)
 112 {
 113         void *devp;
 114         int rc = -1;
 115
 116         devp = serial_get_stdout_devp();
 117         if (devp == NULL)
 118                 goto err_out;
 119
 120         if (dt_is_compatible(devp, "ns16550"))
 121                 rc = ns16550_console_init(devp, &serial_cd);
 122         else if (dt_is_compatible(devp, "marvell,mpsc"))
 123                 rc = mpsc_console_init(devp, &serial_cd);
 124         else if (dt_is_compatible(devp, "fsl,cpm1-scc-uart") ||
 125                  dt_is_compatible(devp, "fsl,cpm1-smc-uart") ||
 126                  dt_is_compatible(devp, "fsl,cpm2-scc-uart") ||
 127                  dt_is_compatible(devp, "fsl,cpm2-smc-uart"))
 128                 rc = cpm_console_init(devp, &serial_cd);
 129         else if (dt_is_compatible(devp, "fsl,mpc5200-psc-uart"))
 130                 rc = mpc5200_psc_console_init(devp, &serial_cd);
 131         else if (dt_is_compatible(devp, "xlnx,opb-uartlite-1.00.b") ||
 132                  dt_is_compatible(devp, "xlnx,xps-uartlite-1.00.a"))
 133                 rc = uartlite_console_init(devp, &serial_cd);
 134
 135         /* Add other serial console driver calls here */
 136
 137         if (!rc) {
 138                 console_ops.open = serial_open;
 139                 console_ops.write = serial_write;
 140                 console_ops.close = serial_close;
 141                 console_ops.data = &serial_cd;
 142
 143                 if (serial_cd.getc)
 144                         console_ops.edit_cmdline = serial_edit_cmdline;
 145
 146                 return 0;
 147         }
 148 err_out:
 149         return -1;
 150 }