[deliverable/linux.git] / arch / tile / kernel / early_printk.c

/*
 * Copyright 2010 Tilera Corporation. All Rights Reserved.
 *
 *   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, version 2.
 *
 *   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, GOOD TITLE or
 *   NON INFRINGEMENT.  See the GNU General Public License for
 *   more details.
 */

#include <linux/console.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/irqflags.h>
#include <linux/printk.h>
#include <asm/setup.h>
#include <hv/hypervisor.h>

static void early_hv_write(struct console *con, const char *s, unsigned n)
{
	hv_console_write((HV_VirtAddr) s, n);
}

static struct console early_hv_console = {
	.name =		"earlyhv",
	.write =	early_hv_write,
	.flags =	CON_PRINTBUFFER,
	.index =	-1,
};

/* Direct interface for emergencies */
static int early_console_complete;

void early_panic(const char *fmt, ...)
{
	va_list ap;
	arch_local_irq_disable_all();
	va_start(ap, fmt);
	early_printk("Kernel panic - not syncing: ");
	early_vprintk(fmt, ap);
	early_console->write(early_console, "\n", 1);
	va_end(ap);
	dump_stack();
	hv_halt();
}

static int __initdata keep_early;

static int __init setup_early_printk(char *str)
{
	if (early_console)
		return 1;

	if (str != NULL && strncmp(str, "keep", 4) == 0)
		keep_early = 1;

	early_console = &early_hv_console;
	register_console(early_console);

	return 0;
}

void __init disable_early_printk(void)
{
	early_console_complete = 1;
	if (!early_console)
		return;
	if (!keep_early) {
		early_printk("disabling early console\n");
		unregister_console(early_console);
		early_console = NULL;
	} else {
		early_printk("keeping early console\n");
	}
}

void warn_early_printk(void)
{
	if (early_console_complete || early_console)
		return;
	early_printk("\
Machine shutting down before console output is fully initialized.\n\
You may wish to reboot and add the option 'earlyprintk' to your\n\
boot command line to see any diagnostic early console output.\n\
");
}

early_param("earlyprintk", setup_early_printk);
Commit	Line	Data
867e359b CM	1	/*
	2	* Copyright 2010 Tilera Corporation. All Rights Reserved.
	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU General Public License
	6	* as published by the Free Software Foundation, version 2.
	7	*
	8	* This program is distributed in the hope that it will be useful, but
	9	* WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
	11	* NON INFRINGEMENT. See the GNU General Public License for
	12	* more details.
	13	*/
	14
	15	#include <linux/console.h>
	16	#include <linux/kernel.h>
	17	#include <linux/init.h>
	18	#include <linux/string.h>
bd119c69	19	#include <linux/irqflags.h>
d0380e6c	20	#include <linux/printk.h>
867e359b CM	21	#include <asm/setup.h>
	22	#include <hv/hypervisor.h>
	23
	24	static void early_hv_write(struct console con, const char s, unsigned n)
	25	{
	26	hv_console_write((HV_VirtAddr) s, n);
	27	}
	28
	29	static struct console early_hv_console = {
	30	.name = "earlyhv",
	31	.write = early_hv_write,
	32	.flags = CON_PRINTBUFFER,
	33	.index = -1,
	34	};
	35
	36	/* Direct interface for emergencies */
867e359b CM	37	static int early_console_complete;
867e359b CM	38
867e359b CM	39	void early_panic(const char *fmt, ...)
	40	{
	41	va_list ap;
5d966115	42	arch_local_irq_disable_all();
867e359b CM	43	va_start(ap, fmt);
	44	early_printk("Kernel panic - not syncing: ");
	45	early_vprintk(fmt, ap);
	46	early_console->write(early_console, "\n", 1);
	47	va_end(ap);
	48	dump_stack();
	49	hv_halt();
	50	}
	51
	52	static int __initdata keep_early;
	53
	54	static int __init setup_early_printk(char *str)
	55	{
d0380e6c	56	if (early_console)
867e359b CM	57	return 1;
	58
	59	if (str != NULL && strncmp(str, "keep", 4) == 0)
	60	keep_early = 1;
	61
	62	early_console = &early_hv_console;
867e359b CM	63	register_console(early_console);
	64
	65	return 0;
	66	}
	67
	68	void __init disable_early_printk(void)
	69	{
	70	early_console_complete = 1;
d0380e6c	71	if (!early_console)
867e359b CM	72	return;
	73	if (!keep_early) {
	74	early_printk("disabling early console\n");
	75	unregister_console(early_console);
d0380e6c	76	early_console = NULL;
867e359b CM	77	} else {
	78	early_printk("keeping early console\n");
	79	}
	80	}
	81
	82	void warn_early_printk(void)
	83	{
d0380e6c	84	if (early_console_complete \|\| early_console)
867e359b CM	85	return;
	86	early_printk("\
	87	Machine shutting down before console output is fully initialized.\n\
	88	You may wish to reboot and add the option 'earlyprintk' to your\n\
	89	boot command line to see any diagnostic early console output.\n\
	90	");
	91	}
	92
	93	early_param("earlyprintk", setup_early_printk);