drivers/bcma/sprom.c

   1 /*
   2  * Broadcom specific AMBA
   3  * SPROM reading
   4  *
   5  * Licensed under the GNU/GPL. See COPYING for details.
   6  */
   7
   8 #include "bcma_private.h"
   9
  10 #include <linux/bcma/bcma.h>
  11 #include <linux/bcma/bcma_regs.h>
  12 #include <linux/pci.h>
  13 #include <linux/io.h>
  14 #include <linux/dma-mapping.h>
  15 #include <linux/slab.h>
  16
  17 #define SPOFF(offset)   ((offset) / sizeof(u16))
  18
  19 /**************************************************
  20  * R/W ops.
  21  **************************************************/
  22
  23 static void bcma_sprom_read(struct bcma_bus *bus, u16 offset, u16 *sprom)
  24 {
  25         int i;
  26         for (i = 0; i < SSB_SPROMSIZE_WORDS_R4; i++)
  27                 sprom[i] = bcma_read16(bus->drv_cc.core,
  28                                        offset + (i * 2));
  29 }
  30
  31 /**************************************************
  32  * Validation.
  33  **************************************************/
  34
  35 static inline u8 bcma_crc8(u8 crc, u8 data)
  36 {
  37         /* Polynomial:   x^8 + x^7 + x^6 + x^4 + x^2 + 1   */
  38         static const u8 t[] = {
  39                 0x00, 0xF7, 0xB9, 0x4E, 0x25, 0xD2, 0x9C, 0x6B,
  40                 0x4A, 0xBD, 0xF3, 0x04, 0x6F, 0x98, 0xD6, 0x21,
  41                 0x94, 0x63, 0x2D, 0xDA, 0xB1, 0x46, 0x08, 0xFF,
  42                 0xDE, 0x29, 0x67, 0x90, 0xFB, 0x0C, 0x42, 0xB5,
  43                 0x7F, 0x88, 0xC6, 0x31, 0x5A, 0xAD, 0xE3, 0x14,
  44                 0x35, 0xC2, 0x8C, 0x7B, 0x10, 0xE7, 0xA9, 0x5E,
  45                 0xEB, 0x1C, 0x52, 0xA5, 0xCE, 0x39, 0x77, 0x80,
  46                 0xA1, 0x56, 0x18, 0xEF, 0x84, 0x73, 0x3D, 0xCA,
  47                 0xFE, 0x09, 0x47, 0xB0, 0xDB, 0x2C, 0x62, 0x95,
  48                 0xB4, 0x43, 0x0D, 0xFA, 0x91, 0x66, 0x28, 0xDF,
  49                 0x6A, 0x9D, 0xD3, 0x24, 0x4F, 0xB8, 0xF6, 0x01,
  50                 0x20, 0xD7, 0x99, 0x6E, 0x05, 0xF2, 0xBC, 0x4B,
  51                 0x81, 0x76, 0x38, 0xCF, 0xA4, 0x53, 0x1D, 0xEA,
  52                 0xCB, 0x3C, 0x72, 0x85, 0xEE, 0x19, 0x57, 0xA0,
  53                 0x15, 0xE2, 0xAC, 0x5B, 0x30, 0xC7, 0x89, 0x7E,
  54                 0x5F, 0xA8, 0xE6, 0x11, 0x7A, 0x8D, 0xC3, 0x34,
  55                 0xAB, 0x5C, 0x12, 0xE5, 0x8E, 0x79, 0x37, 0xC0,
  56                 0xE1, 0x16, 0x58, 0xAF, 0xC4, 0x33, 0x7D, 0x8A,
  57                 0x3F, 0xC8, 0x86, 0x71, 0x1A, 0xED, 0xA3, 0x54,
  58                 0x75, 0x82, 0xCC, 0x3B, 0x50, 0xA7, 0xE9, 0x1E,
  59                 0xD4, 0x23, 0x6D, 0x9A, 0xF1, 0x06, 0x48, 0xBF,
  60                 0x9E, 0x69, 0x27, 0xD0, 0xBB, 0x4C, 0x02, 0xF5,
  61                 0x40, 0xB7, 0xF9, 0x0E, 0x65, 0x92, 0xDC, 0x2B,
  62                 0x0A, 0xFD, 0xB3, 0x44, 0x2F, 0xD8, 0x96, 0x61,
  63                 0x55, 0xA2, 0xEC, 0x1B, 0x70, 0x87, 0xC9, 0x3E,
  64                 0x1F, 0xE8, 0xA6, 0x51, 0x3A, 0xCD, 0x83, 0x74,
  65                 0xC1, 0x36, 0x78, 0x8F, 0xE4, 0x13, 0x5D, 0xAA,
  66                 0x8B, 0x7C, 0x32, 0xC5, 0xAE, 0x59, 0x17, 0xE0,
  67                 0x2A, 0xDD, 0x93, 0x64, 0x0F, 0xF8, 0xB6, 0x41,
  68                 0x60, 0x97, 0xD9, 0x2E, 0x45, 0xB2, 0xFC, 0x0B,
  69                 0xBE, 0x49, 0x07, 0xF0, 0x9B, 0x6C, 0x22, 0xD5,
  70                 0xF4, 0x03, 0x4D, 0xBA, 0xD1, 0x26, 0x68, 0x9F,
  71         };
  72         return t[crc ^ data];
  73 }
  74
  75 static u8 bcma_sprom_crc(const u16 *sprom)
  76 {
  77         int word;
  78         u8 crc = 0xFF;
  79
  80         for (word = 0; word < SSB_SPROMSIZE_WORDS_R4 - 1; word++) {
  81                 crc = bcma_crc8(crc, sprom[word] & 0x00FF);
  82                 crc = bcma_crc8(crc, (sprom[word] & 0xFF00) >> 8);
  83         }
  84         crc = bcma_crc8(crc, sprom[SSB_SPROMSIZE_WORDS_R4 - 1] & 0x00FF);
  85         crc ^= 0xFF;
  86
  87         return crc;
  88 }
  89
  90 static int bcma_sprom_check_crc(const u16 *sprom)
  91 {
  92         u8 crc;
  93         u8 expected_crc;
  94         u16 tmp;
  95
  96         crc = bcma_sprom_crc(sprom);
  97         tmp = sprom[SSB_SPROMSIZE_WORDS_R4 - 1] & SSB_SPROM_REVISION_CRC;
  98         expected_crc = tmp >> SSB_SPROM_REVISION_CRC_SHIFT;
  99         if (crc != expected_crc)
 100                 return -EPROTO;
 101
 102         return 0;
 103 }
 104
 105 static int bcma_sprom_valid(const u16 *sprom)
 106 {
 107         u16 revision;
 108         int err;
 109
 110         err = bcma_sprom_check_crc(sprom);
 111         if (err)
 112                 return err;
 113
 114         revision = sprom[SSB_SPROMSIZE_WORDS_R4 - 1] & SSB_SPROM_REVISION_REV;
 115         if (revision != 8 && revision != 9) {
 116                 pr_err("Unsupported SPROM revision: %d\n", revision);
 117                 return -ENOENT;
 118         }
 119
 120         return 0;
 121 }
 122
 123 /**************************************************
 124  * SPROM extraction.
 125  **************************************************/
 126
 127 static void bcma_sprom_extract_r8(struct bcma_bus *bus, const u16 *sprom)
 128 {
 129         u16 v;
 130         int i;
 131
 132         for (i = 0; i < 3; i++) {
 133                 v = sprom[SPOFF(SSB_SPROM8_IL0MAC) + i];
 134                 *(((__be16 *)bus->sprom.il0mac) + i) = cpu_to_be16(v);
 135         }
 136 }
 137
 138 int bcma_sprom_get(struct bcma_bus *bus)
 139 {
 140         u16 offset;
 141         u16 *sprom;
 142         int err = 0;
 143
 144         if (!bus->drv_cc.core)
 145                 return -EOPNOTSUPP;
 146
 147         if (!(bus->drv_cc.capabilities & BCMA_CC_CAP_SPROM))
 148                 return -ENOENT;
 149
 150         sprom = kcalloc(SSB_SPROMSIZE_WORDS_R4, sizeof(u16),
 151                         GFP_KERNEL);
 152         if (!sprom)
 153                 return -ENOMEM;
 154
 155         /* Most cards have SPROM moved by additional offset 0x30 (48 dwords).
 156          * According to brcm80211 this applies to cards with PCIe rev >= 6
 157          * TODO: understand this condition and use it */
 158         offset = (bus->chipinfo.id == 0x4331) ? BCMA_CC_SPROM :
 159                 BCMA_CC_SPROM_PCIE6;
 160         bcma_sprom_read(bus, offset, sprom);
 161
 162         err = bcma_sprom_valid(sprom);
 163         if (err)
 164                 goto out;
 165
 166         bcma_sprom_extract_r8(bus, sprom);
 167
 168 out:
 169         kfree(sprom);
 170         return err;
 171 }