blob: 215d78c87bc515d2e5142de76430dbd9bc468b9f [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 *
16 *
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by
19 * the Free Software Foundation; either version 2 of the License, or
20 * (at your option) any later version.
21 *
22 * This program is distributed in the hope that it will be useful,
23 * but WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
25 * GNU General Public License for more details.
26 *
27 * You should have received a copy of the GNU General Public License
28 * along with this program; if not, write to the Free Software
29 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
30 */
31
32/*
33 * The PDC console is a simple console, which can be used for debugging
34 * boot related problems on HP PA-RISC machines.
35 *
36 * This code uses the ROM (=PDC) based functions to read and write characters
37 * from and to PDC's boot path.
38 * Since all character read from that path must be polled, this code never
39 * can or will be a fully functional linux console.
40 */
41
42/* Define EARLY_BOOTUP_DEBUG to debug kernel related boot problems.
43 * On production kernels EARLY_BOOTUP_DEBUG should be undefined. */
Matthew Wilcox7c92e972005-10-21 22:50:06 -040044#define EARLY_BOOTUP_DEBUG
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
46
47#include <linux/config.h>
48#include <linux/kernel.h>
49#include <linux/console.h>
50#include <linux/string.h>
51#include <linux/init.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070052#include <linux/major.h>
53#include <linux/tty.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070054#include <asm/pdc.h> /* for iodc_call() proto and friends */
55
56
57static void pdc_console_write(struct console *co, const char *s, unsigned count)
58{
59 while(count--)
60 pdc_iodc_putc(*s++);
61}
62
63void pdc_outc(unsigned char c)
64{
65 pdc_iodc_outc(c);
66}
67
68void pdc_printf(const char *fmt, ...)
69{
70 va_list args;
71 char buf[1024];
72 int i, len;
73
74 va_start(args, fmt);
75 len = vscnprintf(buf, sizeof(buf), fmt, args);
76 va_end(args);
77
78 for (i = 0; i < len; i++)
79 pdc_iodc_outc(buf[i]);
80}
81
82int pdc_console_poll_key(struct console *co)
83{
84 return pdc_iodc_getc();
85}
86
87static int pdc_console_setup(struct console *co, char *options)
88{
89 return 0;
90}
91
92#if defined(CONFIG_PDC_CONSOLE)
Linus Torvalds1da177e2005-04-16 15:20:36 -070093static struct tty_driver * pdc_console_device (struct console *c, int *index)
94{
95 extern struct tty_driver console_driver;
96 *index = c->index ? c->index-1 : fg_console;
97 return &console_driver;
98}
99#else
Matthew Wilcox7c92e972005-10-21 22:50:06 -0400100#define pdc_console_device NULL
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101#endif
102
103static struct console pdc_cons = {
104 .name = "ttyB",
105 .write = pdc_console_write,
Matthew Wilcox7c92e972005-10-21 22:50:06 -0400106 .device = pdc_console_device,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 .setup = pdc_console_setup,
Matthew Wilcox7c92e972005-10-21 22:50:06 -0400108 .flags = CON_BOOT | CON_PRINTBUFFER | CON_ENABLED,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109 .index = -1,
110};
111
112static int pdc_console_initialized;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113
114static void pdc_console_init_force(void)
115{
116 if (pdc_console_initialized)
117 return;
118 ++pdc_console_initialized;
119
120 /* If the console is duplex then copy the COUT parameters to CIN. */
121 if (PAGE0->mem_cons.cl_class == CL_DUPLEX)
122 memcpy(&PAGE0->mem_kbd, &PAGE0->mem_cons, sizeof(PAGE0->mem_cons));
123
124 /* register the pdc console */
125 register_console(&pdc_cons);
126}
127
128void __init pdc_console_init(void)
129{
130#if defined(EARLY_BOOTUP_DEBUG) || defined(CONFIG_PDC_CONSOLE)
131 pdc_console_init_force();
132#endif
133#ifdef EARLY_BOOTUP_DEBUG
134 printk(KERN_INFO "Initialized PDC Console for debugging.\n");
135#endif
136}
137
138
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139/*
140 * Used for emergencies. Currently only used if an HPMC occurs. If an
141 * HPMC occurs, it is possible that the current console may not be
Matthew Wilcox7c92e972005-10-21 22:50:06 -0400142 * properly initialised after the PDC IO reset. This routine unregisters
143 * all of the current consoles, reinitializes the pdc console and
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144 * registers it.
145 */
146
147void pdc_console_restart(void)
148{
149 struct console *console;
150
151 if (pdc_console_initialized)
152 return;
153
Matthew Wilcox7c92e972005-10-21 22:50:06 -0400154 /* If we've already seen the output, don't bother to print it again */
155 if (console_drivers != NULL)
156 pdc_cons.flags &= ~CON_PRINTBUFFER;
157
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 while ((console = console_drivers) != NULL)
159 unregister_console(console_drivers);
160
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161 /* force registering the pdc console */
162 pdc_console_init_force();
163}