| xj | b04a402 | 2021-11-25 15:01:52 +0800 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * Copyright (c) 2019 MediaTek Inc. |
| 4 | * Author: Guochun Mao <guochun.mao@mediatek.com> |
| 5 | * Xiaolei Li <xiaolei.li@mediatek.com> |
| 6 | */ |
| 7 | |
| 8 | #include <linux/module.h> |
| 9 | #include <linux/kernel.h> |
| 10 | #include <linux/slab.h> |
| 11 | #include <linux/string.h> |
| 12 | #include <linux/mtd/mtd.h> |
| 13 | #include <linux/mtd/partitions.h> |
| 14 | #include <asm/div64.h> |
| 15 | |
| 16 | #define MAX_PARTITION_COUNT 128 |
| 17 | #define MAX_PARTITION_NAME_LEN 64 |
| 18 | #define PT_SIG 0x50547633 //"PTv3" |
| 19 | #define MPT_SIG 0x4D505433 //"MPT3" |
| 20 | #define PT_SIG_SIZE 8 |
| 21 | |
| 22 | #define is_valid_mpt(buf) ((*(uint32_t *)(buf)) == MPT_SIG) |
| 23 | #define is_valid_pt(buf) ((*(uint32_t *)(buf)) == PT_SIG) |
| 24 | #define is_valid_pt_v1(buf) ((*(uint32_t *)(buf)) == PT_SIG_V1) |
| 25 | |
| 26 | typedef struct |
| 27 | { |
| 28 | unsigned char name[MAX_PARTITION_NAME_LEN]; /* partition name */ |
| 29 | unsigned long long size; /* partition size */ |
| 30 | unsigned long long part_id; /* partition region */ //will be used as download type on L branch. xiaolei |
| 31 | unsigned long long offset; /* partition start */ |
| 32 | unsigned long long mask_flags; /* partition flags */ |
| 33 | } pt_resident; |
| 34 | |
| 35 | static void pmt_add_part(struct mtd_partition *part, char *name, |
| 36 | u64 offset, uint32_t mask_flags, uint64_t size) |
| 37 | { |
| 38 | part->name = kstrdup_const(name, GFP_KERNEL); |
| 39 | part->offset = offset; |
| 40 | part->mask_flags = mask_flags; |
| 41 | part->size = size; |
| 42 | } |
| 43 | |
| 44 | static int pmt_parse(struct mtd_info *master, |
| 45 | const struct mtd_partition **pparts, |
| 46 | struct mtd_part_parser_data *data) |
| 47 | { |
| 48 | struct mtd_partition *parts; |
| 49 | int err, i; |
| 50 | u_char *buf; |
| 51 | u32 pmt_size = sizeof(pt_resident) * MAX_PARTITION_COUNT; |
| 52 | u8 pmt[PT_SIG_SIZE] = {0}; |
| 53 | pt_resident *pt; |
| 54 | size_t bytes_read = 0; |
| 55 | loff_t pmt_start_addr = (loff_t)master->size - 6 * (loff_t)master->erasesize; |
| 56 | u8 max_partition_count = 0; |
| 57 | |
| 58 | dev_dbg(&master->dev, "PMT: enter pmt parser...\n"); |
| 59 | |
| 60 | buf = kzalloc(pmt_size, GFP_KERNEL); |
| 61 | if (buf == NULL) |
| 62 | return -ENOMEM; |
| 63 | |
| 64 | pt = (pt_resident *)buf; |
| 65 | err = mtd_read(master, pmt_start_addr, sizeof(pmt), &bytes_read, pmt); |
| 66 | if (err < 0) |
| 67 | goto freebuf; |
| 68 | |
| 69 | /* look for the PMT tag */ |
| 70 | if (is_valid_mpt(pmt) == 0 && is_valid_pt(pmt) == 0) { |
| 71 | dev_err(&master->dev, "PMT: not find sig in 1st PMT block, try 2nd one\n"); |
| 72 | pmt_start_addr += master->erasesize; |
| 73 | err = mtd_read(master, pmt_start_addr, sizeof(pmt), &bytes_read, pmt); |
| 74 | if (err < 0) |
| 75 | goto freebuf; |
| 76 | if (is_valid_mpt(pmt) == 0 && is_valid_pt(pmt) == 0) { |
| 77 | dev_err(&master->dev, "PMT: not find sig in 2st PMT block, give up\n"); |
| 78 | goto freebuf; |
| 79 | } |
| 80 | } |
| 81 | |
| 82 | err = mtd_read(master, pmt_start_addr + PT_SIG_SIZE, pmt_size, &bytes_read, buf); |
| 83 | if (err < 0) |
| 84 | goto freebuf; |
| 85 | |
| 86 | for (i = 0 ; i < MAX_PARTITION_COUNT ; i++) { |
| 87 | if (strlen(pt[i].name) == 0) |
| 88 | break; |
| 89 | } |
| 90 | max_partition_count = i; |
| 91 | dev_dbg(&master->dev, "pmt there are <%d> parititons.\n", |
| 92 | max_partition_count); |
| 93 | |
| 94 | parts = kcalloc(max_partition_count, |
| 95 | sizeof(struct mtd_partition), GFP_KERNEL); |
| 96 | if (parts == NULL) |
| 97 | goto freebuf; |
| 98 | |
| 99 | for (i = 0 ; i < max_partition_count ; i++) { |
| 100 | pmt_add_part(&parts[i], pt[i].name, |
| 101 | pt[i].offset, 0, pt[i].size); |
| 102 | |
| 103 | } |
| 104 | |
| 105 | parsedone: |
| 106 | *pparts = parts; |
| 107 | kfree(buf); |
| 108 | return max_partition_count; |
| 109 | |
| 110 | freebuf: |
| 111 | kfree(buf); |
| 112 | return 0; |
| 113 | }; |
| 114 | |
| 115 | static struct mtd_part_parser pmt_parser = { |
| 116 | .owner = THIS_MODULE, |
| 117 | .parse_fn = pmt_parse, |
| 118 | .name = "pmtpart", |
| 119 | }; |
| 120 | |
| 121 | static int __init pmtpart_init(void) |
| 122 | { |
| 123 | return register_mtd_parser(&pmt_parser); |
| 124 | } |
| 125 | |
| 126 | static void __exit pmtpart_exit(void) |
| 127 | { |
| 128 | deregister_mtd_parser(&pmt_parser); |
| 129 | } |
| 130 | |
| 131 | module_init(pmtpart_init); |
| 132 | module_exit(pmtpart_exit); |
| 133 | |
| 134 | MODULE_LICENSE("GPL v2"); |
| 135 | MODULE_DESCRIPTION("PMT partitioning for flash memories"); |