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-rw-r--r--drivers/serial/kgdboc.c268
1 files changed, 0 insertions, 268 deletions
diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
deleted file mode 100644
index 39f9a1adaa75..000000000000
--- a/drivers/serial/kgdboc.c
+++ /dev/null
@@ -1,268 +0,0 @@
1/*
2 * Based on the same principle as kgdboe using the NETPOLL api, this
3 * driver uses a console polling api to implement a gdb serial inteface
4 * which is multiplexed on a console port.
5 *
6 * Maintainer: Jason Wessel <jason.wessel@windriver.com>
7 *
8 * 2007-2008 (c) Jason Wessel - Wind River Systems, Inc.
9 *
10 * This file is licensed under the terms of the GNU General Public
11 * License version 2. This program is licensed "as is" without any
12 * warranty of any kind, whether express or implied.
13 */
14#include <linux/kernel.h>
15#include <linux/ctype.h>
16#include <linux/kgdb.h>
17#include <linux/kdb.h>
18#include <linux/tty.h>
19#include <linux/console.h>
20#include <linux/vt_kern.h>
21
22#define MAX_CONFIG_LEN 40
23
24static struct kgdb_io kgdboc_io_ops;
25
26/* -1 = init not run yet, 0 = unconfigured, 1 = configured. */
27static int configured = -1;
28
29static char config[MAX_CONFIG_LEN];
30static struct kparam_string kps = {
31 .string = config,
32 .maxlen = MAX_CONFIG_LEN,
33};
34
35static int kgdboc_use_kms; /* 1 if we use kernel mode switching */
36static struct tty_driver *kgdb_tty_driver;
37static int kgdb_tty_line;
38
39#ifdef CONFIG_KDB_KEYBOARD
40static int kgdboc_register_kbd(char **cptr)
41{
42 if (strncmp(*cptr, "kbd", 3) == 0) {
43 if (kdb_poll_idx < KDB_POLL_FUNC_MAX) {
44 kdb_poll_funcs[kdb_poll_idx] = kdb_get_kbd_char;
45 kdb_poll_idx++;
46 if (cptr[0][3] == ',')
47 *cptr += 4;
48 else
49 return 1;
50 }
51 }
52 return 0;
53}
54
55static void kgdboc_unregister_kbd(void)
56{
57 int i;
58
59 for (i = 0; i < kdb_poll_idx; i++) {
60 if (kdb_poll_funcs[i] == kdb_get_kbd_char) {
61 kdb_poll_idx--;
62 kdb_poll_funcs[i] = kdb_poll_funcs[kdb_poll_idx];
63 kdb_poll_funcs[kdb_poll_idx] = NULL;
64 i--;
65 }
66 }
67}
68#else /* ! CONFIG_KDB_KEYBOARD */
69#define kgdboc_register_kbd(x) 0
70#define kgdboc_unregister_kbd()
71#endif /* ! CONFIG_KDB_KEYBOARD */
72
73static int kgdboc_option_setup(char *opt)
74{
75 if (strlen(opt) > MAX_CONFIG_LEN) {
76 printk(KERN_ERR "kgdboc: config string too long\n");
77 return -ENOSPC;
78 }
79 strcpy(config, opt);
80
81 return 0;
82}
83
84__setup("kgdboc=", kgdboc_option_setup);
85
86static void cleanup_kgdboc(void)
87{
88 kgdboc_unregister_kbd();
89 if (configured == 1)
90 kgdb_unregister_io_module(&kgdboc_io_ops);
91}
92
93static int configure_kgdboc(void)
94{
95 struct tty_driver *p;
96 int tty_line = 0;
97 int err;
98 char *cptr = config;
99 struct console *cons;
100
101 err = kgdboc_option_setup(config);
102 if (err || !strlen(config) || isspace(config[0]))
103 goto noconfig;
104
105 err = -ENODEV;
106 kgdboc_io_ops.is_console = 0;
107 kgdb_tty_driver = NULL;
108
109 kgdboc_use_kms = 0;
110 if (strncmp(cptr, "kms,", 4) == 0) {
111 cptr += 4;
112 kgdboc_use_kms = 1;
113 }
114
115 if (kgdboc_register_kbd(&cptr))
116 goto do_register;
117
118 p = tty_find_polling_driver(cptr, &tty_line);
119 if (!p)
120 goto noconfig;
121
122 cons = console_drivers;
123 while (cons) {
124 int idx;
125 if (cons->device && cons->device(cons, &idx) == p &&
126 idx == tty_line) {
127 kgdboc_io_ops.is_console = 1;
128 break;
129 }
130 cons = cons->next;
131 }
132
133 kgdb_tty_driver = p;
134 kgdb_tty_line = tty_line;
135
136do_register:
137 err = kgdb_register_io_module(&kgdboc_io_ops);
138 if (err)
139 goto noconfig;
140
141 configured = 1;
142
143 return 0;
144
145noconfig:
146 config[0] = 0;
147 configured = 0;
148 cleanup_kgdboc();
149
150 return err;
151}
152
153static int __init init_kgdboc(void)
154{
155 /* Already configured? */
156 if (configured == 1)
157 return 0;
158
159 return configure_kgdboc();
160}
161
162static int kgdboc_get_char(void)
163{
164 if (!kgdb_tty_driver)
165 return -1;
166 return kgdb_tty_driver->ops->poll_get_char(kgdb_tty_driver,
167 kgdb_tty_line);
168}
169
170static void kgdboc_put_char(u8 chr)
171{
172 if (!kgdb_tty_driver)
173 return;
174 kgdb_tty_driver->ops->poll_put_char(kgdb_tty_driver,
175 kgdb_tty_line, chr);
176}
177
178static int param_set_kgdboc_var(const char *kmessage, struct kernel_param *kp)
179{
180 int len = strlen(kmessage);
181
182 if (len >= MAX_CONFIG_LEN) {
183 printk(KERN_ERR "kgdboc: config string too long\n");
184 return -ENOSPC;
185 }
186
187 /* Only copy in the string if the init function has not run yet */
188 if (configured < 0) {
189 strcpy(config, kmessage);
190 return 0;
191 }
192
193 if (kgdb_connected) {
194 printk(KERN_ERR
195 "kgdboc: Cannot reconfigure while KGDB is connected.\n");
196
197 return -EBUSY;
198 }
199
200 strcpy(config, kmessage);
201 /* Chop out \n char as a result of echo */
202 if (config[len - 1] == '\n')
203 config[len - 1] = '\0';
204
205 if (configured == 1)
206 cleanup_kgdboc();
207
208 /* Go and configure with the new params. */
209 return configure_kgdboc();
210}
211
212static int dbg_restore_graphics;
213
214static void kgdboc_pre_exp_handler(void)
215{
216 if (!dbg_restore_graphics && kgdboc_use_kms) {
217 dbg_restore_graphics = 1;
218 con_debug_enter(vc_cons[fg_console].d);
219 }
220 /* Increment the module count when the debugger is active */
221 if (!kgdb_connected)
222 try_module_get(THIS_MODULE);
223}
224
225static void kgdboc_post_exp_handler(void)
226{
227 /* decrement the module count when the debugger detaches */
228 if (!kgdb_connected)
229 module_put(THIS_MODULE);
230 if (kgdboc_use_kms && dbg_restore_graphics) {
231 dbg_restore_graphics = 0;
232 con_debug_leave();
233 }
234}
235
236static struct kgdb_io kgdboc_io_ops = {
237 .name = "kgdboc",
238 .read_char = kgdboc_get_char,
239 .write_char = kgdboc_put_char,
240 .pre_exception = kgdboc_pre_exp_handler,
241 .post_exception = kgdboc_post_exp_handler,
242};
243
244#ifdef CONFIG_KGDB_SERIAL_CONSOLE
245/* This is only available if kgdboc is a built in for early debugging */
246int __init kgdboc_early_init(char *opt)
247{
248 /* save the first character of the config string because the
249 * init routine can destroy it.
250 */
251 char save_ch;
252
253 kgdboc_option_setup(opt);
254 save_ch = config[0];
255 init_kgdboc();
256 config[0] = save_ch;
257 return 0;
258}
259
260early_param("ekgdboc", kgdboc_early_init);
261#endif /* CONFIG_KGDB_SERIAL_CONSOLE */
262
263module_init(init_kgdboc);
264module_exit(cleanup_kgdboc);
265module_param_call(kgdboc, param_set_kgdboc_var, param_get_string, &kps, 0644);
266MODULE_PARM_DESC(kgdboc, "<serial_device>[,baud]");
267MODULE_DESCRIPTION("KGDB Console TTY Driver");
268MODULE_LICENSE("GPL");
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