Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * printf.c: Internal prom library printf facility. |
| 3 | * |
| 4 | * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) |
| 5 | * Copyright (c) 2002 Pete Zaitcev (zaitcev@yahoo.com) |
| 6 | * |
| 7 | * We used to warn all over the code: DO NOT USE prom_printf(), |
Simon Arlott | d1a78c3 | 2007-05-11 13:51:23 -0700 | [diff] [blame] | 8 | * and yet people do. Anton's banking code was outputting banks |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | * with prom_printf for most of the 2.4 lifetime. Since an effective |
| 10 | * stick is not available, we deployed a carrot: an early printk |
| 11 | * through PROM by means of -p boot option. This ought to fix it. |
| 12 | * USE printk; if you need, deploy -p. |
| 13 | */ |
| 14 | |
| 15 | #include <linux/kernel.h> |
| 16 | |
| 17 | #include <asm/openprom.h> |
| 18 | #include <asm/oplib.h> |
| 19 | |
| 20 | static char ppbuf[1024]; |
| 21 | |
| 22 | void |
| 23 | prom_write(const char *buf, unsigned int n) |
| 24 | { |
| 25 | char ch; |
| 26 | |
| 27 | while (n != 0) { |
| 28 | --n; |
| 29 | if ((ch = *buf++) == '\n') |
| 30 | prom_putchar('\r'); |
| 31 | prom_putchar(ch); |
| 32 | } |
| 33 | } |
| 34 | |
| 35 | void |
| 36 | prom_printf(char *fmt, ...) |
| 37 | { |
| 38 | va_list args; |
| 39 | int i; |
| 40 | |
| 41 | va_start(args, fmt); |
| 42 | i = vscnprintf(ppbuf, sizeof(ppbuf), fmt, args); |
| 43 | va_end(args); |
| 44 | |
| 45 | prom_write(ppbuf, i); |
| 46 | } |