diff options
Diffstat (limited to 'arch/parisc/kernel/pdc_cons.c')
| -rw-r--r-- | arch/parisc/kernel/pdc_cons.c | 213 |
1 files changed, 153 insertions, 60 deletions
diff --git a/arch/parisc/kernel/pdc_cons.c b/arch/parisc/kernel/pdc_cons.c index 01f676d1673..d5cae55195e 100644 --- a/arch/parisc/kernel/pdc_cons.c +++ b/arch/parisc/kernel/pdc_cons.c @@ -12,6 +12,7 @@ * 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 @@ -31,95 +32,203 @@ /* * The PDC console is a simple console, which can be used for debugging - * boot related problems on HP PA-RISC machines. + * 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. - * 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 +#define 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/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) { - while(count--) - pdc_iodc_putc(*s++); + 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); } -void pdc_outc(unsigned char c) +int pdc_console_poll_key(struct console *co) { - pdc_iodc_outc(c); + 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; } -void pdc_printf(const char *fmt, ...) +static int pdc_console_setup(struct console *co, char *options) { - va_list args; - char buf[1024]; - int i, len; + return 0; +} - va_start(args, fmt); - len = vscnprintf(buf, sizeof(buf), fmt, args); - va_end(args); +#if defined(CONFIG_PDC_CONSOLE) +#include <linux/vt_kern.h> +#include <linux/tty_flip.h> - for (i = 0; i < len; i++) - pdc_iodc_outc(buf[i]); +#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; } -int pdc_console_poll_key(struct console *co) +static void pdc_console_tty_close(struct tty_struct *tty, struct file *filp) { - return pdc_iodc_getc(); + if (tty->count == 1) { + del_timer_sync(&pdc_console_timer); + tty_port_tty_set(&tty_port, NULL); + } } -static int pdc_console_setup(struct console *co, char *options) +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; } -#if defined(CONFIG_PDC_CONSOLE) -#define PDC_CONSOLE_DEVICE pdc_console_device +module_init(pdc_console_tty_driver_init); + 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; + *index = c->index; + return pdc_console_tty_driver; } #else -#define PDC_CONSOLE_DEVICE NULL +#define pdc_console_device NULL #endif static struct console pdc_cons = { .name = "ttyB", .write = pdc_console_write, - .device = PDC_CONSOLE_DEVICE, + .device = pdc_console_device, .setup = pdc_console_setup, - .flags = CON_BOOT|CON_PRINTBUFFER|CON_ENABLED, + .flags = CON_BOOT | CON_PRINTBUFFER, .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) { @@ -146,27 +255,11 @@ void __init pdc_console_init(void) } -/* 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 + * properly initialised after the PDC IO reset. This routine unregisters + * all of the current consoles, reinitializes the pdc console and * registers it. */ @@ -177,13 +270,13 @@ void pdc_console_restart(void) 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); - /* Don't repeat what we've already printed */ - con_start = log_end; - /* force registering the pdc console */ pdc_console_init_force(); } - |