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