/* * 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/page.h> /* for PAGE0 */ #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 == 1) { 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; while (1) { data = pdc_console_poll_key(NULL); if (data == -1) break; tty_insert_flip_char(&tty_port, data & 0xFF, TTY_NORMAL); count ++; } if (count) tty_flip_buffer_push(&tty_port); 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; pdc_console_tty_driver = alloc_tty_driver(1); if (!pdc_console_tty_driver) return -ENOMEM; tty_port_init(&tty_port); 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); tty_port_link_device(&tty_port, pdc_console_tty_driver, 0); err = tty_register_driver(pdc_console_tty_driver); if (err) { printk(KERN_ERR "Unable to register the PDC console TTY driver\n"); tty_port_destroy(&tty_port); return err; } return 0; } device_initcall(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(); }