| /* |
| * PDC Console support - ie use firmware to dump text via boot console |
| * |
| * Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org> |
| * Copyright (C) 2000 Martin K Petersen <mkp at mkp.net> |
| * Copyright (C) 2000 John Marvin <jsm at parisc-linux.org> |
| * Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org> |
| * Copyright (C) 2000 Philipp Rumpf <prumpf with tux.org> |
| * Copyright (C) 2000 Michael Ang <mang with subcarrier.org> |
| * Copyright (C) 2000 Grant Grundler <grundler with parisc-linux.org> |
| * Copyright (C) 2001-2002 Ryan Bradetich <rbrad at parisc-linux.org> |
| * Copyright (C) 2001 Helge Deller <deller at parisc-linux.org> |
| * Copyright (C) 2001 Thomas Bogendoerfer <tsbogend at parisc-linux.org> |
| * Copyright (C) 2002 Randolph Chung <tausq with parisc-linux.org> |
| * Copyright (C) 2010 Guy Martin <gmsoft at tuxicoman.be> |
| * |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| |
| /* |
| * The PDC console is a simple console, which can be used for debugging |
| * boot related problems on HP PA-RISC machines. It is also useful when no |
| * other console works. |
| * |
| * This code uses the ROM (=PDC) based functions to read and write characters |
| * from and to PDC's boot path. |
| */ |
| |
| /* Define EARLY_BOOTUP_DEBUG to debug kernel related boot problems. |
| * On production kernels EARLY_BOOTUP_DEBUG should be undefined. */ |
| #define EARLY_BOOTUP_DEBUG |
| |
| |
| #include <linux/kernel.h> |
| #include <linux/console.h> |
| #include <linux/string.h> |
| #include <linux/init.h> |
| #include <linux/major.h> |
| #include <linux/tty.h> |
| #include <asm/pdc.h> /* for iodc_call() proto and friends */ |
| |
| static DEFINE_SPINLOCK(pdc_console_lock); |
| static struct console pdc_cons; |
| |
| static void pdc_console_write(struct console *co, const char *s, unsigned count) |
| { |
| int i = 0; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&pdc_console_lock, flags); |
| do { |
| i += pdc_iodc_print(s + i, count - i); |
| } while (i < count); |
| spin_unlock_irqrestore(&pdc_console_lock, flags); |
| } |
| |
| int pdc_console_poll_key(struct console *co) |
| { |
| int c; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&pdc_console_lock, flags); |
| c = pdc_iodc_getc(); |
| spin_unlock_irqrestore(&pdc_console_lock, flags); |
| |
| return c; |
| } |
| |
| static int pdc_console_setup(struct console *co, char *options) |
| { |
| return 0; |
| } |
| |
| #if defined(CONFIG_PDC_CONSOLE) |
| #include <linux/vt_kern.h> |
| #include <linux/tty_flip.h> |
| |
| #define PDC_CONS_POLL_DELAY (30 * HZ / 1000) |
| |
| static void pdc_console_poll(unsigned long unused); |
| static DEFINE_TIMER(pdc_console_timer, pdc_console_poll, 0, 0); |
| static struct tty_port tty_port; |
| |
| static int pdc_console_tty_open(struct tty_struct *tty, struct file *filp) |
| { |
| tty_port_tty_set(&tty_port, tty); |
| mod_timer(&pdc_console_timer, jiffies + PDC_CONS_POLL_DELAY); |
| |
| return 0; |
| } |
| |
| static void pdc_console_tty_close(struct tty_struct *tty, struct file *filp) |
| { |
| if (!tty->count) { |
| del_timer_sync(&pdc_console_timer); |
| tty_port_tty_set(&tty_port, NULL); |
| } |
| } |
| |
| static int pdc_console_tty_write(struct tty_struct *tty, const unsigned char *buf, int count) |
| { |
| pdc_console_write(NULL, buf, count); |
| return count; |
| } |
| |
| static int pdc_console_tty_write_room(struct tty_struct *tty) |
| { |
| return 32768; /* no limit, no buffer used */ |
| } |
| |
| static int pdc_console_tty_chars_in_buffer(struct tty_struct *tty) |
| { |
| return 0; /* no buffer */ |
| } |
| |
| static const struct tty_operations pdc_console_tty_ops = { |
| .open = pdc_console_tty_open, |
| .close = pdc_console_tty_close, |
| .write = pdc_console_tty_write, |
| .write_room = pdc_console_tty_write_room, |
| .chars_in_buffer = pdc_console_tty_chars_in_buffer, |
| }; |
| |
| static void pdc_console_poll(unsigned long unused) |
| { |
| int data, count = 0; |
| struct tty_struct *tty = tty_port_tty_get(&tty_port); |
| |
| if (!tty) |
| return; |
| |
| while (1) { |
| data = pdc_console_poll_key(NULL); |
| if (data == -1) |
| break; |
| tty_insert_flip_char(tty, data & 0xFF, TTY_NORMAL); |
| count ++; |
| } |
| |
| if (count) |
| tty_flip_buffer_push(tty); |
| |
| tty_kref_put(tty); |
| |
| if (pdc_cons.flags & CON_ENABLED) |
| mod_timer(&pdc_console_timer, jiffies + PDC_CONS_POLL_DELAY); |
| } |
| |
| static struct tty_driver *pdc_console_tty_driver; |
| |
| static int __init pdc_console_tty_driver_init(void) |
| { |
| int err; |
| |
| /* Check if the console driver is still registered. |
| * It is unregistered if the pdc console was not selected as the |
| * primary console. */ |
| |
| struct console *tmp; |
| |
| console_lock(); |
| for_each_console(tmp) |
| if (tmp == &pdc_cons) |
| break; |
| console_unlock(); |
| |
| if (!tmp) { |
| printk(KERN_INFO "PDC console driver not registered anymore, not creating %s\n", pdc_cons.name); |
| return -ENODEV; |
| } |
| |
| printk(KERN_INFO "The PDC console driver is still registered, removing CON_BOOT flag\n"); |
| pdc_cons.flags &= ~CON_BOOT; |
| |
| tty_port_init(&tty_port); |
| |
| pdc_console_tty_driver = alloc_tty_driver(1); |
| |
| if (!pdc_console_tty_driver) |
| return -ENOMEM; |
| |
| pdc_console_tty_driver->driver_name = "pdc_cons"; |
| pdc_console_tty_driver->name = "ttyB"; |
| pdc_console_tty_driver->major = MUX_MAJOR; |
| pdc_console_tty_driver->minor_start = 0; |
| pdc_console_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM; |
| pdc_console_tty_driver->init_termios = tty_std_termios; |
| pdc_console_tty_driver->flags = TTY_DRIVER_REAL_RAW | |
| TTY_DRIVER_RESET_TERMIOS; |
| tty_set_operations(pdc_console_tty_driver, &pdc_console_tty_ops); |
| |
| err = tty_register_driver(pdc_console_tty_driver); |
| if (err) { |
| printk(KERN_ERR "Unable to register the PDC console TTY driver\n"); |
| return err; |
| } |
| |
| return 0; |
| } |
| |
| module_init(pdc_console_tty_driver_init); |
| |
| static struct tty_driver * pdc_console_device (struct console *c, int *index) |
| { |
| *index = c->index; |
| return pdc_console_tty_driver; |
| } |
| #else |
| #define pdc_console_device NULL |
| #endif |
| |
| static struct console pdc_cons = { |
| .name = "ttyB", |
| .write = pdc_console_write, |
| .device = pdc_console_device, |
| .setup = pdc_console_setup, |
| .flags = CON_BOOT | CON_PRINTBUFFER, |
| .index = -1, |
| }; |
| |
| static int pdc_console_initialized; |
| |
| static void pdc_console_init_force(void) |
| { |
| if (pdc_console_initialized) |
| return; |
| ++pdc_console_initialized; |
| |
| /* If the console is duplex then copy the COUT parameters to CIN. */ |
| if (PAGE0->mem_cons.cl_class == CL_DUPLEX) |
| memcpy(&PAGE0->mem_kbd, &PAGE0->mem_cons, sizeof(PAGE0->mem_cons)); |
| |
| /* register the pdc console */ |
| register_console(&pdc_cons); |
| } |
| |
| void __init pdc_console_init(void) |
| { |
| #if defined(EARLY_BOOTUP_DEBUG) || defined(CONFIG_PDC_CONSOLE) |
| pdc_console_init_force(); |
| #endif |
| #ifdef EARLY_BOOTUP_DEBUG |
| printk(KERN_INFO "Initialized PDC Console for debugging.\n"); |
| #endif |
| } |
| |
| |
| /* |
| * Used for emergencies. Currently only used if an HPMC occurs. If an |
| * HPMC occurs, it is possible that the current console may not be |
| * properly initialised after the PDC IO reset. This routine unregisters |
| * all of the current consoles, reinitializes the pdc console and |
| * registers it. |
| */ |
| |
| void pdc_console_restart(void) |
| { |
| struct console *console; |
| |
| if (pdc_console_initialized) |
| return; |
| |
| /* If we've already seen the output, don't bother to print it again */ |
| if (console_drivers != NULL) |
| pdc_cons.flags &= ~CON_PRINTBUFFER; |
| |
| while ((console = console_drivers) != NULL) |
| unregister_console(console_drivers); |
| |
| /* force registering the pdc console */ |
| pdc_console_init_force(); |
| } |