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(), 8 * and yet people do. Anton's banking code was outputting banks 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 } 47