/* * 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> * * * 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. * * This code uses the ROM (=PDC) based functions to read and write characters * from and to PDC's boot path. * Since all character read from that path must be polled, this code never * can or will be a fully functional linux console. */ /* 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 void pdc_console_write(struct console *co, const char *s, unsigned count) { while(count--) pdc_iodc_putc(*s++); } void pdc_outc(unsigned char c) { pdc_iodc_outc(c); } void pdc_printf(const char *fmt, ...) { va_list args; char buf[1024]; int i, len; va_start(args, fmt); len = vscnprintf(buf, sizeof(buf), fmt, args); va_end(args); for (i = 0; i < len; i++) pdc_iodc_outc(buf[i]); } int pdc_console_poll_key(struct console *co) { return pdc_iodc_getc(); } static int pdc_console_setup(struct console *co, char *options) { return 0; } #if defined(CONFIG_PDC_CONSOLE) #include <linux/vt_kern.h> static struct tty_driver * pdc_console_device (struct console *c, int *index) { extern struct tty_driver console_driver; *index = c->index ? c->index-1 : fg_console; return &console_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 | CON_ENABLED, .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(); }