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-rw-r--r--arch/parisc/kernel/pdc_cons.c189
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diff --git a/arch/parisc/kernel/pdc_cons.c b/arch/parisc/kernel/pdc_cons.c
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+/*
+ * 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. */
+#undef EARLY_BOOTUP_DEBUG
+
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/console.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/major.h>
+#include <linux/tty.h>
+#include <asm/page.h>
+#include <asm/types.h>
+#include <asm/system.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)
+#define PDC_CONSOLE_DEVICE pdc_console_device
+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;
+extern unsigned long con_start; /* kernel/printk.c */
+extern unsigned long log_end; /* kernel/printk.c */
+
+
+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
+}
+
+
+/* Unregister the pdc console with the printk console layer */
+void pdc_console_die(void)
+{
+ if (!pdc_console_initialized)
+ return;
+ --pdc_console_initialized;
+
+ printk(KERN_INFO "Switching from PDC console\n");
+
+ /* Don't repeat what we've already printed */
+ con_start = log_end;
+
+ unregister_console(&pdc_cons);
+}
+
+
+/*
+ * 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 initialed 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;
+
+ while ((console = console_drivers) != NULL)
+ unregister_console(console_drivers);
+
+ /* Don't repeat what we've already printed */
+ con_start = log_end;
+
+ /* force registering the pdc console */
+ pdc_console_init_force();
+}
+