Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
at v3.8 93 lines 2.5 kB view raw
1/* 2 * Copyright (C) 1999, 2000, 2004, 2005 MIPS Technologies, Inc. 3 * All rights reserved. 4 * Authors: Carsten Langgaard <carstenl@mips.com> 5 * Maciej W. Rozycki <macro@mips.com> 6 * Portions copyright (C) 2009 Cisco Systems, Inc. 7 * 8 * This program is free software; you can distribute it and/or modify it 9 * under the terms of the GNU General Public License (Version 2) as 10 * published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope it will be useful, but WITHOUT 13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15 * for more details. 16 * 17 * You should have received a copy of the GNU General Public License along 18 * with this program; if not, write to the Free Software Foundation, Inc., 19 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. 20 * 21 * PROM library initialisation code. 22 */ 23#include <linux/init.h> 24#include <linux/string.h> 25#include <linux/kernel.h> 26 27#include <asm/bootinfo.h> 28#include <linux/io.h> 29#include <asm/cacheflush.h> 30#include <asm/traps.h> 31 32#include <asm/mips-boards/prom.h> 33#include <asm/mips-boards/generic.h> 34#include <asm/mach-powertv/asic.h> 35 36static int *_prom_envp; 37unsigned long _prom_memsize; 38 39/* 40 * YAMON (32-bit PROM) pass arguments and environment as 32-bit pointer. 41 * This macro take care of sign extension, if running in 64-bit mode. 42 */ 43#define prom_envp(index) ((char *)(long)_prom_envp[(index)]) 44 45char *prom_getenv(char *envname) 46{ 47 char *result = NULL; 48 49 if (_prom_envp != NULL) { 50 /* 51 * Return a pointer to the given environment variable. 52 * In 64-bit mode: we're using 64-bit pointers, but all pointers 53 * in the PROM structures are only 32-bit, so we need some 54 * workarounds, if we are running in 64-bit mode. 55 */ 56 int i, index = 0; 57 58 i = strlen(envname); 59 60 while (prom_envp(index)) { 61 if (strncmp(envname, prom_envp(index), i) == 0) { 62 result = prom_envp(index + 1); 63 break; 64 } 65 index += 2; 66 } 67 } 68 69 return result; 70} 71 72void __init prom_init(void) 73{ 74 int prom_argc; 75 char *prom_argv; 76 77 prom_argc = fw_arg0; 78 prom_argv = (char *) fw_arg1; 79 _prom_envp = (int *) fw_arg2; 80 _prom_memsize = (unsigned long) fw_arg3; 81 82 if (prom_argc == 1) { 83 strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE); 84 strlcat(arcs_cmdline, prom_argv, COMMAND_LINE_SIZE); 85 } 86 87 configure_platform(); 88 prom_meminit(); 89 90#ifndef CONFIG_BOOTLOADER_DRIVER 91 pr_info("\nBootloader driver isn't loaded...\n"); 92#endif 93}