--- /dev/null
+/*
+ * 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;
+}
+
+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();
+}
Code Review / kvmfornfv.git / blobdiff