[deliverable/linux.git] / arch / sparc / prom / printf.c

/*
 * printf.c:  Internal prom library printf facility.
 *
 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
 * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
 * Copyright (c) 2002 Pete Zaitcev (zaitcev@yahoo.com)
 *
 * We used to warn all over the code: DO NOT USE prom_printf(),
 * and yet people do. Anton's banking code was outputting banks
 * with prom_printf for most of the 2.4 lifetime. Since an effective
 * stick is not available, we deployed a carrot: an early printk
 * through PROM by means of -p boot option. This ought to fix it.
 * USE printk; if you need, deploy -p.
 */

#include <linux/kernel.h>
#include <linux/compiler.h>
#include <linux/spinlock.h>

#include <asm/openprom.h>
#include <asm/oplib.h>

#define CONSOLE_WRITE_BUF_SIZE	1024

static char ppbuf[1024];
static char console_write_buf[CONSOLE_WRITE_BUF_SIZE];
static DEFINE_RAW_SPINLOCK(console_write_lock);

void notrace prom_write(const char *buf, unsigned int n)
{
	unsigned int dest_len;
	unsigned long flags;
	char *dest;

	dest = console_write_buf;
	raw_spin_lock_irqsave(&console_write_lock, flags);

	dest_len = 0;
	while (n-- != 0) {
		char ch = *buf++;
		if (ch == '\n') {
			*dest++ = '\r';
			dest_len++;
		}
		*dest++ = ch;
		dest_len++;
		if (dest_len >= CONSOLE_WRITE_BUF_SIZE - 1) {
			prom_console_write_buf(console_write_buf, dest_len);
			dest = console_write_buf;
			dest_len = 0;
		}
	}
	if (dest_len)
		prom_console_write_buf(console_write_buf, dest_len);

	raw_spin_unlock_irqrestore(&console_write_lock, flags);
}

void notrace prom_printf(const char *fmt, ...)
{
	va_list args;
	int i;

	va_start(args, fmt);
	i = vscnprintf(ppbuf, sizeof(ppbuf), fmt, args);
	va_end(args);

	prom_write(ppbuf, i);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* printf.c: Internal prom library printf facility.
	3	*
	4	* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
	5	* Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
	6	* Copyright (c) 2002 Pete Zaitcev (zaitcev@yahoo.com)
	7	*
	8	* We used to warn all over the code: DO NOT USE prom_printf(),
	9	* and yet people do. Anton's banking code was outputting banks
	10	* with prom_printf for most of the 2.4 lifetime. Since an effective
	11	* stick is not available, we deployed a carrot: an early printk
	12	* through PROM by means of -p boot option. This ought to fix it.
	13	* USE printk; if you need, deploy -p.
	14	*/
	15
	16	#include <linux/kernel.h>
bd4352ca	17	#include <linux/compiler.h>
595a251c	18	#include <linux/spinlock.h>
1da177e4 LT	19
	20	#include <asm/openprom.h>
	21	#include <asm/oplib.h>
	22
595a251c DM	23	#define CONSOLE_WRITE_BUF_SIZE 1024
595a251c DM	24
1da177e4	25	static char ppbuf[1024];
595a251c DM	26	static char console_write_buf[CONSOLE_WRITE_BUF_SIZE];
595a251c DM	27	static DEFINE_RAW_SPINLOCK(console_write_lock);
1da177e4	28
bd4352ca	29	void notrace prom_write(const char *buf, unsigned int n)
1da177e4	30	{
595a251c DM	31	unsigned int dest_len;
	32	unsigned long flags;
	33	char *dest;
	34
	35	dest = console_write_buf;
	36	raw_spin_lock_irqsave(&console_write_lock, flags);
	37
	38	dest_len = 0;
e62cac1f	39	while (n-- != 0) {
595a251c	40	char ch = *buf++;
e62cac1f	41	if (ch == '\n') {
595a251c DM	42	*dest++ = '\r';
	43	dest_len++;
	44	}
	45	*dest++ = ch;
	46	dest_len++;
	47	if (dest_len >= CONSOLE_WRITE_BUF_SIZE - 1) {
	48	prom_console_write_buf(console_write_buf, dest_len);
	49	dest = console_write_buf;
	50	dest_len = 0;
e62cac1f	51	}
1da177e4	52	}
595a251c DM	53	if (dest_len)
	54	prom_console_write_buf(console_write_buf, dest_len);
	55
	56	raw_spin_unlock_irqrestore(&console_write_lock, flags);
1da177e4 LT	57	}
1da177e4 LT	58
bd4352ca	59	void notrace prom_printf(const char *fmt, ...)
1da177e4 LT	60	{
	61	va_list args;
	62	int i;
	63
	64	va_start(args, fmt);
	65	i = vscnprintf(ppbuf, sizeof(ppbuf), fmt, args);
	66	va_end(args);
	67
	68	prom_write(ppbuf, i);
	69	}