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1/*
2 * PDC Console support - ie use firmware to dump text via boot console
3 *
4 * Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
5 * Copyright (C) 2000 Martin K Petersen <mkp at mkp.net>
6 * Copyright (C) 2000 John Marvin <jsm at parisc-linux.org>
7 * Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
8 * Copyright (C) 2000 Philipp Rumpf <prumpf with tux.org>
9 * Copyright (C) 2000 Michael Ang <mang with subcarrier.org>
10 * Copyright (C) 2000 Grant Grundler <grundler with parisc-linux.org>
11 * Copyright (C) 2001-2002 Ryan Bradetich <rbrad at parisc-linux.org>
12 * Copyright (C) 2001 Helge Deller <deller at parisc-linux.org>
13 * Copyright (C) 2001 Thomas Bogendoerfer <tsbogend at parisc-linux.org>
14 * Copyright (C) 2002 Randolph Chung <tausq with parisc-linux.org>
15 * Copyright (C) 2010 Guy Martin <gmsoft at tuxicoman.be>
16 *
17 *
18 * This program is free software; you can redistribute it and/or modify
19 * it under the terms of the GNU General Public License as published by
20 * the Free Software Foundation; either version 2 of the License, or
21 * (at your option) any later version.
22 *
23 * This program is distributed in the hope that it will be useful,
24 * but WITHOUT ANY WARRANTY; without even the implied warranty of
25 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
26 * GNU General Public License for more details.
27 *
28 * You should have received a copy of the GNU General Public License
29 * along with this program; if not, write to the Free Software
30 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
31 */
32
33/*
34 * The PDC console is a simple console, which can be used for debugging
35 * boot related problems on HP PA-RISC machines. It is also useful when no
36 * other console works.
37 *
38 * This code uses the ROM (=PDC) based functions to read and write characters
39 * from and to PDC's boot path.
40 */
41
42/* Define EARLY_BOOTUP_DEBUG to debug kernel related boot problems.
43 * On production kernels EARLY_BOOTUP_DEBUG should be undefined. */
44#define EARLY_BOOTUP_DEBUG
45
46
47#include <linux/kernel.h>
48#include <linux/console.h>
49#include <linux/string.h>
50#include <linux/init.h>
51#include <linux/major.h>
52#include <linux/tty.h>
53#include <asm/page.h> /* for PAGE0 */
54#include <asm/pdc.h> /* for iodc_call() proto and friends */
55
56static DEFINE_SPINLOCK(pdc_console_lock);
57static struct console pdc_cons;
58
59static void pdc_console_write(struct console *co, const char *s, unsigned count)
60{
61 int i = 0;
62 unsigned long flags;
63
64 spin_lock_irqsave(&pdc_console_lock, flags);
65 do {
66 i += pdc_iodc_print(s + i, count - i);
67 } while (i < count);
68 spin_unlock_irqrestore(&pdc_console_lock, flags);
69}
70
71int pdc_console_poll_key(struct console *co)
72{
73 int c;
74 unsigned long flags;
75
76 spin_lock_irqsave(&pdc_console_lock, flags);
77 c = pdc_iodc_getc();
78 spin_unlock_irqrestore(&pdc_console_lock, flags);
79
80 return c;
81}
82
83static int pdc_console_setup(struct console *co, char *options)
84{
85 return 0;
86}
87
88#if defined(CONFIG_PDC_CONSOLE)
89#include <linux/vt_kern.h>
90#include <linux/tty_flip.h>
91
92#define PDC_CONS_POLL_DELAY (30 * HZ / 1000)
93
94static void pdc_console_poll(unsigned long unused);
95static DEFINE_TIMER(pdc_console_timer, pdc_console_poll, 0, 0);
96static struct tty_port tty_port;
97
98static int pdc_console_tty_open(struct tty_struct *tty, struct file *filp)
99{
100 tty_port_tty_set(&tty_port, tty);
101 mod_timer(&pdc_console_timer, jiffies + PDC_CONS_POLL_DELAY);
102
103 return 0;
104}
105
106static void pdc_console_tty_close(struct tty_struct *tty, struct file *filp)
107{
108 if (tty->count == 1) {
109 del_timer_sync(&pdc_console_timer);
110 tty_port_tty_set(&tty_port, NULL);
111 }
112}
113
114static int pdc_console_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
115{
116 pdc_console_write(NULL, buf, count);
117 return count;
118}
119
120static int pdc_console_tty_write_room(struct tty_struct *tty)
121{
122 return 32768; /* no limit, no buffer used */
123}
124
125static int pdc_console_tty_chars_in_buffer(struct tty_struct *tty)
126{
127 return 0; /* no buffer */
128}
129
130static const struct tty_operations pdc_console_tty_ops = {
131 .open = pdc_console_tty_open,
132 .close = pdc_console_tty_close,
133 .write = pdc_console_tty_write,
134 .write_room = pdc_console_tty_write_room,
135 .chars_in_buffer = pdc_console_tty_chars_in_buffer,
136};
137
138static void pdc_console_poll(unsigned long unused)
139{
140 int data, count = 0;
141
142 while (1) {
143 data = pdc_console_poll_key(NULL);
144 if (data == -1)
145 break;
146 tty_insert_flip_char(&tty_port, data & 0xFF, TTY_NORMAL);
147 count ++;
148 }
149
150 if (count)
151 tty_flip_buffer_push(&tty_port);
152
153 if (pdc_cons.flags & CON_ENABLED)
154 mod_timer(&pdc_console_timer, jiffies + PDC_CONS_POLL_DELAY);
155}
156
157static struct tty_driver *pdc_console_tty_driver;
158
159static int __init pdc_console_tty_driver_init(void)
160{
161 int err;
162
163 /* Check if the console driver is still registered.
164 * It is unregistered if the pdc console was not selected as the
165 * primary console. */
166
167 struct console *tmp;
168
169 console_lock();
170 for_each_console(tmp)
171 if (tmp == &pdc_cons)
172 break;
173 console_unlock();
174
175 if (!tmp) {
176 printk(KERN_INFO "PDC console driver not registered anymore, not creating %s\n", pdc_cons.name);
177 return -ENODEV;
178 }
179
180 printk(KERN_INFO "The PDC console driver is still registered, removing CON_BOOT flag\n");
181 pdc_cons.flags &= ~CON_BOOT;
182
183 pdc_console_tty_driver = alloc_tty_driver(1);
184
185 if (!pdc_console_tty_driver)
186 return -ENOMEM;
187
188 tty_port_init(&tty_port);
189
190 pdc_console_tty_driver->driver_name = "pdc_cons";
191 pdc_console_tty_driver->name = "ttyB";
192 pdc_console_tty_driver->major = MUX_MAJOR;
193 pdc_console_tty_driver->minor_start = 0;
194 pdc_console_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;
195 pdc_console_tty_driver->init_termios = tty_std_termios;
196 pdc_console_tty_driver->flags = TTY_DRIVER_REAL_RAW |
197 TTY_DRIVER_RESET_TERMIOS;
198 tty_set_operations(pdc_console_tty_driver, &pdc_console_tty_ops);
199 tty_port_link_device(&tty_port, pdc_console_tty_driver, 0);
200
201 err = tty_register_driver(pdc_console_tty_driver);
202 if (err) {
203 printk(KERN_ERR "Unable to register the PDC console TTY driver\n");
204 tty_port_destroy(&tty_port);
205 return err;
206 }
207
208 return 0;
209}
210device_initcall(pdc_console_tty_driver_init);
211
212static struct tty_driver * pdc_console_device (struct console *c, int *index)
213{
214 *index = c->index;
215 return pdc_console_tty_driver;
216}
217#else
218#define pdc_console_device NULL
219#endif
220
221static struct console pdc_cons = {
222 .name = "ttyB",
223 .write = pdc_console_write,
224 .device = pdc_console_device,
225 .setup = pdc_console_setup,
226 .flags = CON_BOOT | CON_PRINTBUFFER,
227 .index = -1,
228};
229
230static int pdc_console_initialized;
231
232static void pdc_console_init_force(void)
233{
234 if (pdc_console_initialized)
235 return;
236 ++pdc_console_initialized;
237
238 /* If the console is duplex then copy the COUT parameters to CIN. */
239 if (PAGE0->mem_cons.cl_class == CL_DUPLEX)
240 memcpy(&PAGE0->mem_kbd, &PAGE0->mem_cons, sizeof(PAGE0->mem_cons));
241
242 /* register the pdc console */
243 register_console(&pdc_cons);
244}
245
246void __init pdc_console_init(void)
247{
248#if defined(EARLY_BOOTUP_DEBUG) || defined(CONFIG_PDC_CONSOLE)
249 pdc_console_init_force();
250#endif
251#ifdef EARLY_BOOTUP_DEBUG
252 printk(KERN_INFO "Initialized PDC Console for debugging.\n");
253#endif
254}
255
256
257/*
258 * Used for emergencies. Currently only used if an HPMC occurs. If an
259 * HPMC occurs, it is possible that the current console may not be
260 * properly initialised after the PDC IO reset. This routine unregisters
261 * all of the current consoles, reinitializes the pdc console and
262 * registers it.
263 */
264
265void pdc_console_restart(void)
266{
267 struct console *console;
268
269 if (pdc_console_initialized)
270 return;
271
272 /* If we've already seen the output, don't bother to print it again */
273 if (console_drivers != NULL)
274 pdc_cons.flags &= ~CON_PRINTBUFFER;
275
276 while ((console = console_drivers) != NULL)
277 unregister_console(console_drivers);
278
279 /* force registering the pdc console */
280 pdc_console_init_force();
281}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * PDC Console support - ie use firmware to dump text via boot console
4 *
5 * Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
6 * Copyright (C) 2000 Martin K Petersen <mkp at mkp.net>
7 * Copyright (C) 2000 John Marvin <jsm at parisc-linux.org>
8 * Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
9 * Copyright (C) 2000 Philipp Rumpf <prumpf with tux.org>
10 * Copyright (C) 2000 Michael Ang <mang with subcarrier.org>
11 * Copyright (C) 2000 Grant Grundler <grundler with parisc-linux.org>
12 * Copyright (C) 2001-2002 Ryan Bradetich <rbrad at parisc-linux.org>
13 * Copyright (C) 2001 Helge Deller <deller at parisc-linux.org>
14 * Copyright (C) 2001 Thomas Bogendoerfer <tsbogend at parisc-linux.org>
15 * Copyright (C) 2002 Randolph Chung <tausq with parisc-linux.org>
16 * Copyright (C) 2010 Guy Martin <gmsoft at tuxicoman.be>
17 */
18
19/*
20 * The PDC console is a simple console, which can be used for debugging
21 * boot related problems on HP PA-RISC machines. It is also useful when no
22 * other console works.
23 *
24 * This code uses the ROM (=PDC) based functions to read and write characters
25 * from and to PDC's boot path.
26 */
27
28/* Define EARLY_BOOTUP_DEBUG to debug kernel related boot problems.
29 * On production kernels EARLY_BOOTUP_DEBUG should be undefined. */
30#define EARLY_BOOTUP_DEBUG
31
32
33#include <linux/kernel.h>
34#include <linux/console.h>
35#include <linux/string.h>
36#include <linux/init.h>
37#include <linux/major.h>
38#include <linux/tty.h>
39#include <asm/page.h> /* for PAGE0 */
40#include <asm/pdc.h> /* for iodc_call() proto and friends */
41
42static DEFINE_SPINLOCK(pdc_console_lock);
43static struct console pdc_cons;
44
45static void pdc_console_write(struct console *co, const char *s, unsigned count)
46{
47 int i = 0;
48 unsigned long flags;
49
50 spin_lock_irqsave(&pdc_console_lock, flags);
51 do {
52 i += pdc_iodc_print(s + i, count - i);
53 } while (i < count);
54 spin_unlock_irqrestore(&pdc_console_lock, flags);
55}
56
57int pdc_console_poll_key(struct console *co)
58{
59 int c;
60 unsigned long flags;
61
62 spin_lock_irqsave(&pdc_console_lock, flags);
63 c = pdc_iodc_getc();
64 spin_unlock_irqrestore(&pdc_console_lock, flags);
65
66 return c;
67}
68
69static int pdc_console_setup(struct console *co, char *options)
70{
71 return 0;
72}
73
74#if defined(CONFIG_PDC_CONSOLE)
75#include <linux/vt_kern.h>
76#include <linux/tty_flip.h>
77
78#define PDC_CONS_POLL_DELAY (30 * HZ / 1000)
79
80static void pdc_console_poll(struct timer_list *unused);
81static DEFINE_TIMER(pdc_console_timer, pdc_console_poll);
82static struct tty_port tty_port;
83
84static int pdc_console_tty_open(struct tty_struct *tty, struct file *filp)
85{
86 tty_port_tty_set(&tty_port, tty);
87 mod_timer(&pdc_console_timer, jiffies + PDC_CONS_POLL_DELAY);
88
89 return 0;
90}
91
92static void pdc_console_tty_close(struct tty_struct *tty, struct file *filp)
93{
94 if (tty->count == 1) {
95 del_timer_sync(&pdc_console_timer);
96 tty_port_tty_set(&tty_port, NULL);
97 }
98}
99
100static int pdc_console_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
101{
102 pdc_console_write(NULL, buf, count);
103 return count;
104}
105
106static int pdc_console_tty_write_room(struct tty_struct *tty)
107{
108 return 32768; /* no limit, no buffer used */
109}
110
111static int pdc_console_tty_chars_in_buffer(struct tty_struct *tty)
112{
113 return 0; /* no buffer */
114}
115
116static const struct tty_operations pdc_console_tty_ops = {
117 .open = pdc_console_tty_open,
118 .close = pdc_console_tty_close,
119 .write = pdc_console_tty_write,
120 .write_room = pdc_console_tty_write_room,
121 .chars_in_buffer = pdc_console_tty_chars_in_buffer,
122};
123
124static void pdc_console_poll(struct timer_list *unused)
125{
126 int data, count = 0;
127
128 while (1) {
129 data = pdc_console_poll_key(NULL);
130 if (data == -1)
131 break;
132 tty_insert_flip_char(&tty_port, data & 0xFF, TTY_NORMAL);
133 count ++;
134 }
135
136 if (count)
137 tty_flip_buffer_push(&tty_port);
138
139 if (pdc_cons.flags & CON_ENABLED)
140 mod_timer(&pdc_console_timer, jiffies + PDC_CONS_POLL_DELAY);
141}
142
143static struct tty_driver *pdc_console_tty_driver;
144
145static int __init pdc_console_tty_driver_init(void)
146{
147 int err;
148
149 /* Check if the console driver is still registered.
150 * It is unregistered if the pdc console was not selected as the
151 * primary console. */
152
153 struct console *tmp;
154
155 console_lock();
156 for_each_console(tmp)
157 if (tmp == &pdc_cons)
158 break;
159 console_unlock();
160
161 if (!tmp) {
162 printk(KERN_INFO "PDC console driver not registered anymore, not creating %s\n", pdc_cons.name);
163 return -ENODEV;
164 }
165
166 printk(KERN_INFO "The PDC console driver is still registered, removing CON_BOOT flag\n");
167 pdc_cons.flags &= ~CON_BOOT;
168
169 pdc_console_tty_driver = alloc_tty_driver(1);
170
171 if (!pdc_console_tty_driver)
172 return -ENOMEM;
173
174 tty_port_init(&tty_port);
175
176 pdc_console_tty_driver->driver_name = "pdc_cons";
177 pdc_console_tty_driver->name = "ttyB";
178 pdc_console_tty_driver->major = MUX_MAJOR;
179 pdc_console_tty_driver->minor_start = 0;
180 pdc_console_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;
181 pdc_console_tty_driver->init_termios = tty_std_termios;
182 pdc_console_tty_driver->flags = TTY_DRIVER_REAL_RAW |
183 TTY_DRIVER_RESET_TERMIOS;
184 tty_set_operations(pdc_console_tty_driver, &pdc_console_tty_ops);
185 tty_port_link_device(&tty_port, pdc_console_tty_driver, 0);
186
187 err = tty_register_driver(pdc_console_tty_driver);
188 if (err) {
189 printk(KERN_ERR "Unable to register the PDC console TTY driver\n");
190 tty_port_destroy(&tty_port);
191 return err;
192 }
193
194 return 0;
195}
196device_initcall(pdc_console_tty_driver_init);
197
198static struct tty_driver * pdc_console_device (struct console *c, int *index)
199{
200 *index = c->index;
201 return pdc_console_tty_driver;
202}
203#else
204#define pdc_console_device NULL
205#endif
206
207static struct console pdc_cons = {
208 .name = "ttyB",
209 .write = pdc_console_write,
210 .device = pdc_console_device,
211 .setup = pdc_console_setup,
212 .flags = CON_BOOT | CON_PRINTBUFFER,
213 .index = -1,
214};
215
216static int pdc_console_initialized;
217
218static void pdc_console_init_force(void)
219{
220 if (pdc_console_initialized)
221 return;
222 ++pdc_console_initialized;
223
224 /* If the console is duplex then copy the COUT parameters to CIN. */
225 if (PAGE0->mem_cons.cl_class == CL_DUPLEX)
226 memcpy(&PAGE0->mem_kbd, &PAGE0->mem_cons, sizeof(PAGE0->mem_cons));
227
228 /* register the pdc console */
229 register_console(&pdc_cons);
230}
231
232void __init pdc_console_init(void)
233{
234#if defined(EARLY_BOOTUP_DEBUG) || defined(CONFIG_PDC_CONSOLE)
235 pdc_console_init_force();
236#endif
237#ifdef EARLY_BOOTUP_DEBUG
238 printk(KERN_INFO "Initialized PDC Console for debugging.\n");
239#endif
240}
241
242
243/*
244 * Used for emergencies. Currently only used if an HPMC occurs. If an
245 * HPMC occurs, it is possible that the current console may not be
246 * properly initialised after the PDC IO reset. This routine unregisters
247 * all of the current consoles, reinitializes the pdc console and
248 * registers it.
249 */
250
251void pdc_console_restart(void)
252{
253 struct console *console;
254
255 if (pdc_console_initialized)
256 return;
257
258 /* If we've already seen the output, don't bother to print it again */
259 if (console_drivers != NULL)
260 pdc_cons.flags &= ~CON_PRINTBUFFER;
261
262 while ((console = console_drivers) != NULL)
263 unregister_console(console_drivers);
264
265 /* force registering the pdc console */
266 pdc_console_init_force();
267}