1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Generic serial console support |
4 | * |
5 | * Author: Mark A. Greer <mgreer@mvista.com> |
6 | * |
7 | * Code in serial_edit_cmdline() copied from <file:arch/ppc/boot/simple/misc.c> |
8 | * and was written by Matt Porter <mporter@kernel.crashing.org>. |
9 | * |
10 | * 2001,2006 (c) MontaVista Software, Inc. |
11 | */ |
12 | #include <stdarg.h> |
13 | #include <stddef.h> |
14 | #include "types.h" |
15 | #include "string.h" |
16 | #include "stdio.h" |
17 | #include "io.h" |
18 | #include "ops.h" |
19 | |
20 | static int serial_open(void) |
21 | { |
22 | struct serial_console_data *scdp = console_ops.data; |
23 | return scdp->open(); |
24 | } |
25 | |
26 | static void serial_write(const char *buf, int len) |
27 | { |
28 | struct serial_console_data *scdp = console_ops.data; |
29 | |
30 | while (*buf != '\0') |
31 | scdp->putc(*buf++); |
32 | } |
33 | |
34 | static void serial_edit_cmdline(char *buf, int len, unsigned int timeout) |
35 | { |
36 | int timer = 0, count; |
37 | char ch, *cp; |
38 | struct serial_console_data *scdp = console_ops.data; |
39 | |
40 | cp = buf; |
41 | count = strlen(buf); |
42 | cp = &buf[count]; |
43 | count++; |
44 | |
45 | do { |
46 | if (scdp->tstc()) { |
47 | while (((ch = scdp->getc()) != '\n') && (ch != '\r')) { |
48 | /* Test for backspace/delete */ |
49 | if ((ch == '\b') || (ch == '\177')) { |
50 | if (cp != buf) { |
51 | cp--; |
52 | count--; |
53 | printf(fmt: "\b \b" ); |
54 | } |
55 | /* Test for ^x/^u (and wipe the line) */ |
56 | } else if ((ch == '\030') || (ch == '\025')) { |
57 | while (cp != buf) { |
58 | cp--; |
59 | count--; |
60 | printf(fmt: "\b \b" ); |
61 | } |
62 | } else if (count < len) { |
63 | *cp++ = ch; |
64 | count++; |
65 | scdp->putc(ch); |
66 | } |
67 | } |
68 | break; /* Exit 'timer' loop */ |
69 | } |
70 | udelay(delay: 1000); /* 1 msec */ |
71 | } while (timer++ < timeout); |
72 | *cp = 0; |
73 | } |
74 | |
75 | static void serial_close(void) |
76 | { |
77 | struct serial_console_data *scdp = console_ops.data; |
78 | |
79 | if (scdp->close) |
80 | scdp->close(); |
81 | } |
82 | |
83 | static void *serial_get_stdout_devp(void) |
84 | { |
85 | void *devp; |
86 | char devtype[MAX_PROP_LEN]; |
87 | char path[MAX_PATH_LEN]; |
88 | |
89 | devp = finddevice(name: "/chosen" ); |
90 | if (devp == NULL) |
91 | goto err_out; |
92 | |
93 | if (getprop(devp, name: "linux,stdout-path" , buf: path, MAX_PATH_LEN) > 0 || |
94 | getprop(devp, name: "stdout-path" , buf: path, MAX_PATH_LEN) > 0) { |
95 | devp = finddevice(name: path); |
96 | if (devp == NULL) |
97 | goto err_out; |
98 | |
99 | if ((getprop(devp, name: "device_type" , buf: devtype, buflen: sizeof(devtype)) > 0) |
100 | && !strcmp(s1: devtype, s2: "serial" )) |
101 | return devp; |
102 | } |
103 | err_out: |
104 | return NULL; |
105 | } |
106 | |
107 | static struct serial_console_data serial_cd; |
108 | |
109 | /* Node's "compatible" property determines which serial driver to use */ |
110 | int serial_console_init(void) |
111 | { |
112 | void *devp; |
113 | int rc = -1; |
114 | |
115 | devp = serial_get_stdout_devp(); |
116 | if (devp == NULL) |
117 | goto err_out; |
118 | |
119 | if (dt_is_compatible(node: devp, compat: "ns16550" ) || |
120 | dt_is_compatible(node: devp, compat: "pnpPNP,501" )) |
121 | rc = ns16550_console_init(devp, scdp: &serial_cd); |
122 | #ifdef CONFIG_CPM |
123 | else if (dt_is_compatible(devp, "fsl,cpm1-scc-uart" ) || |
124 | dt_is_compatible(devp, "fsl,cpm1-smc-uart" ) || |
125 | dt_is_compatible(devp, "fsl,cpm2-scc-uart" ) || |
126 | dt_is_compatible(devp, "fsl,cpm2-smc-uart" )) |
127 | rc = cpm_console_init(devp, &serial_cd); |
128 | #endif |
129 | #ifdef CONFIG_PPC_MPC52xx |
130 | else if (dt_is_compatible(devp, "fsl,mpc5200-psc-uart" )) |
131 | rc = mpc5200_psc_console_init(devp, &serial_cd); |
132 | #endif |
133 | #ifdef CONFIG_PPC_POWERNV |
134 | else if (dt_is_compatible(devp, "ibm,opal-console-raw" )) |
135 | rc = opal_console_init(devp, &serial_cd); |
136 | #endif |
137 | |
138 | /* Add other serial console driver calls here */ |
139 | |
140 | if (!rc) { |
141 | console_ops.open = serial_open; |
142 | console_ops.write = serial_write; |
143 | console_ops.close = serial_close; |
144 | console_ops.data = &serial_cd; |
145 | |
146 | if (serial_cd.getc) |
147 | console_ops.edit_cmdline = serial_edit_cmdline; |
148 | |
149 | return 0; |
150 | } |
151 | err_out: |
152 | return -1; |
153 | } |
154 | |