1 /* 2 * This file is subject to the terms and conditions of the GNU General Public 3 * License. See the file "COPYING" in the main directory of this archive 4 * for more details. 5 * 6 * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr> 7 * Copyright (C) 2008 Florian Fainelli <florian@openwrt.org> 8 * Copyright (C) 2012 Jonas Gorski <jonas.gorski@gmail.com> 9 */ 10 11 #define pr_fmt(fmt) "bcm63xx_nvram: " fmt 12 13 #include <linux/init.h> 14 #include <linux/crc32.h> 15 #include <linux/export.h> 16 #include <linux/kernel.h> 17 #include <linux/if_ether.h> 18 19 #include <bcm63xx_nvram.h> 20 21 /* 22 * nvram structure 23 */ 24 struct bcm963xx_nvram { 25 u32 version; 26 u8 reserved1[256]; 27 u8 name[16]; 28 u32 main_tp_number; 29 u32 psi_size; 30 u32 mac_addr_count; 31 u8 mac_addr_base[ETH_ALEN]; 32 u8 reserved2[2]; 33 u32 checksum_old; 34 u8 reserved3[720]; 35 u32 checksum_high; 36 }; 37 38 #define BCM63XX_DEFAULT_PSI_SIZE 64 39 40 static struct bcm963xx_nvram nvram; 41 static int mac_addr_used; 42 43 void __init bcm63xx_nvram_init(void *addr) 44 { 45 unsigned int check_len; 46 u32 crc, expected_crc; 47 u8 hcs_mac_addr[ETH_ALEN] = { 0x00, 0x10, 0x18, 0xff, 0xff, 0xff }; 48 49 /* extract nvram data */ 50 memcpy(&nvram, addr, sizeof(nvram)); 51 52 /* check checksum before using data */ 53 if (nvram.version <= 4) { 54 check_len = offsetof(struct bcm963xx_nvram, reserved3); 55 expected_crc = nvram.checksum_old; 56 nvram.checksum_old = 0; 57 } else { 58 check_len = sizeof(nvram); 59 expected_crc = nvram.checksum_high; 60 nvram.checksum_high = 0; 61 } 62 63 crc = crc32_le(~0, (u8 *)&nvram, check_len); 64 65 if (crc != expected_crc) 66 pr_warn("nvram checksum failed, contents may be invalid (expected %08x, got %08x)\n", 67 expected_crc, crc); 68 69 /* Cable modems have a different NVRAM which is embedded in the eCos 70 * firmware and not easily extractible, give at least a MAC address 71 * pool. 72 */ 73 if (BCMCPU_IS_3368()) { 74 memcpy(nvram.mac_addr_base, hcs_mac_addr, ETH_ALEN); 75 nvram.mac_addr_count = 2; 76 } 77 } 78 79 u8 *bcm63xx_nvram_get_name(void) 80 { 81 return nvram.name; 82 } 83 EXPORT_SYMBOL(bcm63xx_nvram_get_name); 84 85 int bcm63xx_nvram_get_mac_address(u8 *mac) 86 { 87 u8 *oui; 88 int count; 89 90 if (mac_addr_used >= nvram.mac_addr_count) { 91 pr_err("not enough mac addresses\n"); 92 return -ENODEV; 93 } 94 95 memcpy(mac, nvram.mac_addr_base, ETH_ALEN); 96 oui = mac + ETH_ALEN/2 - 1; 97 count = mac_addr_used; 98 99 while (count--) { 100 u8 *p = mac + ETH_ALEN - 1; 101 102 do { 103 (*p)++; 104 if (*p != 0) 105 break; 106 p--; 107 } while (p != oui); 108 109 if (p == oui) { 110 pr_err("unable to fetch mac address\n"); 111 return -ENODEV; 112 } 113 } 114 115 mac_addr_used++; 116 return 0; 117 } 118 EXPORT_SYMBOL(bcm63xx_nvram_get_mac_address); 119 120 int bcm63xx_nvram_get_psi_size(void) 121 { 122 if (nvram.psi_size > 0) 123 return nvram.psi_size; 124 125 return BCM63XX_DEFAULT_PSI_SIZE; 126 } 127 EXPORT_SYMBOL(bcm63xx_nvram_get_psi_size); 128