1// SPDX-License-Identifier: GPL-2.0
 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>
18#include <linux/compiler.h>
19#include <linux/spinlock.h>
20
21#include <asm/openprom.h>
22#include <asm/oplib.h>
23
24#define CONSOLE_WRITE_BUF_SIZE	1024
25
26static char ppbuf[1024];
27static char console_write_buf[CONSOLE_WRITE_BUF_SIZE];
28static DEFINE_RAW_SPINLOCK(console_write_lock);
29
30void notrace prom_write(const char *buf, unsigned int n)
31{
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;
40	while (n-- != 0) {
41		char ch = *buf++;
42		if (ch == '\n') {
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;
52		}
53	}
54	if (dest_len)
55		prom_console_write_buf(console_write_buf, dest_len);
56
57	raw_spin_unlock_irqrestore(&console_write_lock, flags);
58}
59
60void notrace prom_printf(const char *fmt, ...)
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}

 
 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>
17#include <linux/compiler.h>
18#include <linux/spinlock.h>
19
20#include <asm/openprom.h>
21#include <asm/oplib.h>
22
23#define CONSOLE_WRITE_BUF_SIZE	1024
24
25static char ppbuf[1024];
26static char console_write_buf[CONSOLE_WRITE_BUF_SIZE];
27static DEFINE_RAW_SPINLOCK(console_write_lock);
28
29void notrace prom_write(const char *buf, unsigned int n)
30{
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;
39	while (n-- != 0) {
40		char ch = *buf++;
41		if (ch == '\n') {
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;
51		}
52	}
53	if (dest_len)
54		prom_console_write_buf(console_write_buf, dest_len);
55
56	raw_spin_unlock_irqrestore(&console_write_lock, flags);
57}
58
59void notrace prom_printf(const char *fmt, ...)
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}