LXR linux/include/linux/bcm963xx

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef __LINUX_BCM963XX_NVRAM_H__
   3#define __LINUX_BCM963XX_NVRAM_H__
   4
   5#include <linux/crc32.h>
   6#include <linux/if_ether.h>
   7#include <linux/sizes.h>
   8#include <linux/types.h>
   9
  10/*
  11 * Broadcom BCM963xx SoC board nvram data structure.
  12 *
  13 * The nvram structure varies in size depending on the SoC board version. Use
  14 * the appropriate minimum BCM963XX_NVRAM_*_SIZE define for the information
  15 * you need instead of sizeof(struct bcm963xx_nvram) as this may change.
  16 */
  17
  18#define BCM963XX_NVRAM_V4_SIZE          300
  19#define BCM963XX_NVRAM_V5_SIZE          (1 * SZ_1K)
  20
  21#define BCM963XX_DEFAULT_PSI_SIZE       64
  22
  23enum bcm963xx_nvram_nand_part {
  24        BCM963XX_NVRAM_NAND_PART_BOOT = 0,
  25        BCM963XX_NVRAM_NAND_PART_ROOTFS_1,
  26        BCM963XX_NVRAM_NAND_PART_ROOTFS_2,
  27        BCM963XX_NVRAM_NAND_PART_DATA,
  28        BCM963XX_NVRAM_NAND_PART_BBT,
  29
  30        __BCM963XX_NVRAM_NAND_NR_PARTS
  31};
  32
  33struct bcm963xx_nvram {
  34        u32     version;
  35        char    bootline[256];
  36        char    name[16];
  37        u32     main_tp_number;
  38        u32     psi_size;
  39        u32     mac_addr_count;
  40        u8      mac_addr_base[ETH_ALEN];
  41        u8      __reserved1[2];
  42        u32     checksum_v4;
  43
  44        u8      __reserved2[292];
  45        u32     nand_part_offset[__BCM963XX_NVRAM_NAND_NR_PARTS];
  46        u32     nand_part_size[__BCM963XX_NVRAM_NAND_NR_PARTS];
  47        u8      __reserved3[388];
  48        u32     checksum_v5;
  49};
  50
  51#define BCM963XX_NVRAM_NAND_PART_OFFSET(nvram, part) \
  52        bcm963xx_nvram_nand_part_offset(nvram, BCM963XX_NVRAM_NAND_PART_ ##part)
  53
  54static inline u64 __pure bcm963xx_nvram_nand_part_offset(
  55        const struct bcm963xx_nvram *nvram,
  56        enum bcm963xx_nvram_nand_part part)
  57{
  58        return nvram->nand_part_offset[part] * SZ_1K;
  59}
  60
  61#define BCM963XX_NVRAM_NAND_PART_SIZE(nvram, part) \
  62        bcm963xx_nvram_nand_part_size(nvram, BCM963XX_NVRAM_NAND_PART_ ##part)
  63
  64static inline u64 __pure bcm963xx_nvram_nand_part_size(
  65        const struct bcm963xx_nvram *nvram,
  66        enum bcm963xx_nvram_nand_part part)
  67{
  68        return nvram->nand_part_size[part] * SZ_1K;
  69}
  70
  71/*
  72 * bcm963xx_nvram_checksum - Verify nvram checksum
  73 *
  74 * @nvram: pointer to full size nvram data structure
  75 * @expected_out: optional pointer to store expected checksum value
  76 * @actual_out: optional pointer to store actual checksum value
  77 *
  78 * Return: 0 if the checksum is valid, otherwise -EINVAL
  79 */
  80static int __maybe_unused bcm963xx_nvram_checksum(
  81        const struct bcm963xx_nvram *nvram,
  82        u32 *expected_out, u32 *actual_out)
  83{
  84        u32 expected, actual;
  85        size_t len;
  86
  87        if (nvram->version <= 4) {
  88                expected = nvram->checksum_v4;
  89                len = BCM963XX_NVRAM_V4_SIZE - sizeof(u32);
  90        } else {
  91                expected = nvram->checksum_v5;
  92                len = BCM963XX_NVRAM_V5_SIZE - sizeof(u32);
  93        }
  94
  95        /*
  96         * Calculate the CRC32 value for the nvram with a checksum value
  97         * of 0 without modifying or copying the nvram by combining:
  98         * - The CRC32 of the nvram without the checksum value
  99         * - The CRC32 of a zero checksum value (which is also 0)
 100         */
 101        actual = crc32_le_combine(
 102                crc32_le(~0, (u8 *)nvram, len), 0, sizeof(u32));
 103
 104        if (expected_out)
 105                *expected_out = expected;
 106
 107        if (actual_out)
 108                *actual_out = actual;
 109
 110        return expected == actual ? 0 : -EINVAL;
 111};
 112
 113#endif /* __LINUX_BCM963XX_NVRAM_H__ */
 114