[linux-2.6-block.git] / arch / sparc / prom / printf.c

// SPDX-License-Identifier: GPL-2.0
/*
 * 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
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* printf.c: Internal prom library printf facility.
	4	*
	5	* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
	6	* Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
	7	* Copyright (c) 2002 Pete Zaitcev (zaitcev@yahoo.com)
	8	*
	9	* We used to warn all over the code: DO NOT USE prom_printf(),
	10	* and yet people do. Anton's banking code was outputting banks
	11	* with prom_printf for most of the 2.4 lifetime. Since an effective
	12	* stick is not available, we deployed a carrot: an early printk
	13	* through PROM by means of -p boot option. This ought to fix it.
	14	* USE printk; if you need, deploy -p.
	15	*/
	16
	17	#include <linux/kernel.h>
bd4352ca	18	#include <linux/compiler.h>
595a251c	19	#include <linux/spinlock.h>
1da177e4 LT	20
	21	#include <asm/openprom.h>
	22	#include <asm/oplib.h>
	23
595a251c DM	24	#define CONSOLE_WRITE_BUF_SIZE 1024
595a251c DM	25
1da177e4	26	static char ppbuf[1024];
595a251c DM	27	static char console_write_buf[CONSOLE_WRITE_BUF_SIZE];
595a251c DM	28	static DEFINE_RAW_SPINLOCK(console_write_lock);
1da177e4	29
bd4352ca	30	void notrace prom_write(const char *buf, unsigned int n)
1da177e4	31	{
595a251c DM	32	unsigned int dest_len;
	33	unsigned long flags;
	34	char *dest;
	35
	36	dest = console_write_buf;
	37	raw_spin_lock_irqsave(&console_write_lock, flags);
	38
	39	dest_len = 0;
e62cac1f	40	while (n-- != 0) {
595a251c	41	char ch = *buf++;
e62cac1f	42	if (ch == '\n') {
595a251c DM	43	*dest++ = '\r';
	44	dest_len++;
	45	}
	46	*dest++ = ch;
	47	dest_len++;
	48	if (dest_len >= CONSOLE_WRITE_BUF_SIZE - 1) {
	49	prom_console_write_buf(console_write_buf, dest_len);
	50	dest = console_write_buf;
	51	dest_len = 0;
e62cac1f	52	}
1da177e4	53	}
595a251c DM	54	if (dest_len)
	55	prom_console_write_buf(console_write_buf, dest_len);
	56
	57	raw_spin_unlock_irqrestore(&console_write_lock, flags);
1da177e4 LT	58	}
1da177e4 LT	59
bd4352ca	60	void notrace prom_printf(const char *fmt, ...)
1da177e4 LT	61	{
	62	va_list args;
	63	int i;
	64
	65	va_start(args, fmt);
	66	i = vscnprintf(ppbuf, sizeof(ppbuf), fmt, args);
	67	va_end(args);
	68
	69	prom_write(ppbuf, i);
	70	}