xref: /linux/arch/powerpc/boot/serial.c (revision 4e0ae876f77bc01a7e77724dea57b4b82bd53244)
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 #include "autoconf.h"
22 
23 static int serial_open(void)
24 {
25 	struct serial_console_data *scdp = console_ops.data;
26 	return scdp->open();
27 }
28 
29 static void serial_write(const char *buf, int len)
30 {
31 	struct serial_console_data *scdp = console_ops.data;
32 
33 	while (*buf != '\0')
34 		scdp->putc(*buf++);
35 }
36 
37 static void serial_edit_cmdline(char *buf, int len, unsigned int timeout)
38 {
39 	int timer = 0, count;
40 	char ch, *cp;
41 	struct serial_console_data *scdp = console_ops.data;
42 
43 	cp = buf;
44 	count = strlen(buf);
45 	cp = &buf[count];
46 	count++;
47 
48 	do {
49 		if (scdp->tstc()) {
50 			while (((ch = scdp->getc()) != '\n') && (ch != '\r')) {
51 				/* Test for backspace/delete */
52 				if ((ch == '\b') || (ch == '\177')) {
53 					if (cp != buf) {
54 						cp--;
55 						count--;
56 						printf("\b \b");
57 					}
58 				/* Test for ^x/^u (and wipe the line) */
59 				} else if ((ch == '\030') || (ch == '\025')) {
60 					while (cp != buf) {
61 						cp--;
62 						count--;
63 						printf("\b \b");
64 					}
65 				} else if (count < len) {
66 						*cp++ = ch;
67 						count++;
68 						scdp->putc(ch);
69 				}
70 			}
71 			break;  /* Exit 'timer' loop */
72 		}
73 		udelay(1000);  /* 1 msec */
74 	} while (timer++ < timeout);
75 	*cp = 0;
76 }
77 
78 static void serial_close(void)
79 {
80 	struct serial_console_data *scdp = console_ops.data;
81 
82 	if (scdp->close)
83 		scdp->close();
84 }
85 
86 static void *serial_get_stdout_devp(void)
87 {
88 	void *devp;
89 	char devtype[MAX_PROP_LEN];
90 	char path[MAX_PATH_LEN];
91 
92 	devp = finddevice("/chosen");
93 	if (devp == NULL)
94 		goto err_out;
95 
96 	if (getprop(devp, "linux,stdout-path", path, MAX_PATH_LEN) > 0 ||
97 		getprop(devp, "stdout-path", path, MAX_PATH_LEN) > 0) {
98 		devp = finddevice(path);
99 		if (devp == NULL)
100 			goto err_out;
101 
102 		if ((getprop(devp, "device_type", devtype, sizeof(devtype)) > 0)
103 				&& !strcmp(devtype, "serial"))
104 			return devp;
105 	}
106 err_out:
107 	return NULL;
108 }
109 
110 static struct serial_console_data serial_cd;
111 
112 /* Node's "compatible" property determines which serial driver to use */
113 int serial_console_init(void)
114 {
115 	void *devp;
116 	int rc = -1;
117 
118 	devp = serial_get_stdout_devp();
119 	if (devp == NULL)
120 		goto err_out;
121 
122 	if (dt_is_compatible(devp, "ns16550") ||
123 	    dt_is_compatible(devp, "pnpPNP,501"))
124 		rc = ns16550_console_init(devp, &serial_cd);
125 #ifdef CONFIG_CPM
126 	else if (dt_is_compatible(devp, "fsl,cpm1-scc-uart") ||
127 	         dt_is_compatible(devp, "fsl,cpm1-smc-uart") ||
128 	         dt_is_compatible(devp, "fsl,cpm2-scc-uart") ||
129 	         dt_is_compatible(devp, "fsl,cpm2-smc-uart"))
130 		rc = cpm_console_init(devp, &serial_cd);
131 #endif
132 #ifdef CONFIG_PPC_MPC52XX
133 	else if (dt_is_compatible(devp, "fsl,mpc5200-psc-uart"))
134 		rc = mpc5200_psc_console_init(devp, &serial_cd);
135 #endif
136 #ifdef CONFIG_XILINX_VIRTEX
137 	else if (dt_is_compatible(devp, "xlnx,opb-uartlite-1.00.b") ||
138 		 dt_is_compatible(devp, "xlnx,xps-uartlite-1.00.a"))
139 		rc = uartlite_console_init(devp, &serial_cd);
140 #endif
141 #ifdef CONFIG_PPC64_BOOT_WRAPPER
142 	else if (dt_is_compatible(devp, "ibm,opal-console-raw"))
143 		rc = opal_console_init(devp, &serial_cd);
144 #endif
145 
146 	/* Add other serial console driver calls here */
147 
148 	if (!rc) {
149 		console_ops.open = serial_open;
150 		console_ops.write = serial_write;
151 		console_ops.close = serial_close;
152 		console_ops.data = &serial_cd;
153 
154 		if (serial_cd.getc)
155 			console_ops.edit_cmdline = serial_edit_cmdline;
156 
157 		return 0;
158 	}
159 err_out:
160 	return -1;
161 }
162