1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Qualcomm SMEM NAND flash partition parser
4 *
5 * Copyright (C) 2020, Linaro Ltd.
6 */
7
8 #include <linux/ctype.h>
9 #include <linux/module.h>
10 #include <linux/mtd/mtd.h>
11 #include <linux/mtd/partitions.h>
12 #include <linux/slab.h>
13 #include <linux/soc/qcom/smem.h>
14
15 #define SMEM_AARM_PARTITION_TABLE 9
16 #define SMEM_APPS 0
17
18 #define SMEM_FLASH_PART_MAGIC1 0x55ee73aa
19 #define SMEM_FLASH_PART_MAGIC2 0xe35ebddb
20 #define SMEM_FLASH_PTABLE_V3 3
21 #define SMEM_FLASH_PTABLE_V4 4
22 #define SMEM_FLASH_PTABLE_MAX_PARTS_V3 16
23 #define SMEM_FLASH_PTABLE_MAX_PARTS_V4 48
24 #define SMEM_FLASH_PTABLE_HDR_LEN (4 * sizeof(u32))
25 #define SMEM_FLASH_PTABLE_NAME_SIZE 16
26
27 /**
28 * struct smem_flash_pentry - SMEM Flash partition entry
29 * @name: Name of the partition
30 * @offset: Offset in blocks
31 * @length: Length of the partition in blocks
32 * @attr: Flags for this partition
33 */
34 struct smem_flash_pentry {
35 char name[SMEM_FLASH_PTABLE_NAME_SIZE];
36 __le32 offset;
37 __le32 length;
38 u8 attr;
39 } __packed __aligned(4);
40
41 /**
42 * struct smem_flash_ptable - SMEM Flash partition table
43 * @magic1: Partition table Magic 1
44 * @magic2: Partition table Magic 2
45 * @version: Partition table version
46 * @numparts: Number of partitions in this ptable
47 * @pentry: Flash partition entries belonging to this ptable
48 */
49 struct smem_flash_ptable {
50 __le32 magic1;
51 __le32 magic2;
52 __le32 version;
53 __le32 numparts;
54 struct smem_flash_pentry pentry[SMEM_FLASH_PTABLE_MAX_PARTS_V4];
55 } __packed __aligned(4);
56
parse_qcomsmem_part(struct mtd_info * mtd,const struct mtd_partition ** pparts,struct mtd_part_parser_data * data)57 static int parse_qcomsmem_part(struct mtd_info *mtd,
58 const struct mtd_partition **pparts,
59 struct mtd_part_parser_data *data)
60 {
61 size_t len = SMEM_FLASH_PTABLE_HDR_LEN;
62 int ret, i, j, tmpparts, numparts = 0;
63 struct smem_flash_pentry *pentry;
64 struct smem_flash_ptable *ptable;
65 struct mtd_partition *parts;
66 char *name, *c;
67
68 if (IS_ENABLED(CONFIG_MTD_SPI_NOR_USE_4K_SECTORS)
69 && mtd->type == MTD_NORFLASH) {
70 pr_err("%s: SMEM partition parser is incompatible with 4K sectors\n",
71 mtd->name);
72 return -EINVAL;
73 }
74
75 pr_debug("Parsing partition table info from SMEM\n");
76 ptable = qcom_smem_get(SMEM_APPS, SMEM_AARM_PARTITION_TABLE, &len);
77 if (IS_ERR(ptable)) {
78 if (PTR_ERR(ptable) != -EPROBE_DEFER)
79 pr_err("Error reading partition table header\n");
80 return PTR_ERR(ptable);
81 }
82
83 /* Verify ptable magic */
84 if (le32_to_cpu(ptable->magic1) != SMEM_FLASH_PART_MAGIC1 ||
85 le32_to_cpu(ptable->magic2) != SMEM_FLASH_PART_MAGIC2) {
86 pr_err("Partition table magic verification failed\n");
87 return -EINVAL;
88 }
89
90 /* Ensure that # of partitions is less than the max we have allocated */
91 tmpparts = le32_to_cpu(ptable->numparts);
92 if (tmpparts > SMEM_FLASH_PTABLE_MAX_PARTS_V4) {
93 pr_err("Partition numbers exceed the max limit\n");
94 return -EINVAL;
95 }
96
97 /* Find out length of partition data based on table version */
98 if (le32_to_cpu(ptable->version) <= SMEM_FLASH_PTABLE_V3) {
99 len = SMEM_FLASH_PTABLE_HDR_LEN + SMEM_FLASH_PTABLE_MAX_PARTS_V3 *
100 sizeof(struct smem_flash_pentry);
101 } else if (le32_to_cpu(ptable->version) == SMEM_FLASH_PTABLE_V4) {
102 len = SMEM_FLASH_PTABLE_HDR_LEN + SMEM_FLASH_PTABLE_MAX_PARTS_V4 *
103 sizeof(struct smem_flash_pentry);
104 } else {
105 pr_err("Unknown ptable version (%d)", le32_to_cpu(ptable->version));
106 return -EINVAL;
107 }
108
109 /*
110 * Now that the partition table header has been parsed, verified
111 * and the length of the partition table calculated, read the
112 * complete partition table
113 */
114 ptable = qcom_smem_get(SMEM_APPS, SMEM_AARM_PARTITION_TABLE, &len);
115 if (IS_ERR(ptable)) {
116 pr_err("Error reading partition table\n");
117 return PTR_ERR(ptable);
118 }
119
120 for (i = 0; i < tmpparts; i++) {
121 pentry = &ptable->pentry[i];
122 if (pentry->name[0] != '\0')
123 numparts++;
124 }
125
126 parts = kcalloc(numparts, sizeof(*parts), GFP_KERNEL);
127 if (!parts)
128 return -ENOMEM;
129
130 for (i = 0, j = 0; i < tmpparts; i++) {
131 pentry = &ptable->pentry[i];
132 if (pentry->name[0] == '\0')
133 continue;
134
135 name = kstrdup(pentry->name, GFP_KERNEL);
136 if (!name) {
137 ret = -ENOMEM;
138 goto out_free_parts;
139 }
140
141 /* Convert name to lower case */
142 for (c = name; *c != '\0'; c++)
143 *c = tolower(*c);
144
145 parts[j].name = name;
146 parts[j].offset = le32_to_cpu(pentry->offset) * mtd->erasesize;
147 parts[j].mask_flags = pentry->attr;
148 parts[j].size = le32_to_cpu(pentry->length) * mtd->erasesize;
149 pr_debug("%d: %s offs=0x%08x size=0x%08x attr:0x%08x\n",
150 i, pentry->name, le32_to_cpu(pentry->offset),
151 le32_to_cpu(pentry->length), pentry->attr);
152 j++;
153 }
154
155 pr_debug("SMEM partition table found: ver: %d len: %d\n",
156 le32_to_cpu(ptable->version), tmpparts);
157 *pparts = parts;
158
159 return numparts;
160
161 out_free_parts:
162 while (--j >= 0)
163 kfree(parts[j].name);
164 kfree(parts);
165 *pparts = NULL;
166
167 return ret;
168 }
169
parse_qcomsmem_cleanup(const struct mtd_partition * pparts,int nr_parts)170 static void parse_qcomsmem_cleanup(const struct mtd_partition *pparts,
171 int nr_parts)
172 {
173 int i;
174
175 for (i = 0; i < nr_parts; i++)
176 kfree(pparts[i].name);
177
178 kfree(pparts);
179 }
180
181 static const struct of_device_id qcomsmem_of_match_table[] = {
182 { .compatible = "qcom,smem-part" },
183 {},
184 };
185 MODULE_DEVICE_TABLE(of, qcomsmem_of_match_table);
186
187 static struct mtd_part_parser mtd_parser_qcomsmem = {
188 .parse_fn = parse_qcomsmem_part,
189 .cleanup = parse_qcomsmem_cleanup,
190 .name = "qcomsmem",
191 .of_match_table = qcomsmem_of_match_table,
192 };
193 module_mtd_part_parser(mtd_parser_qcomsmem);
194
195 MODULE_LICENSE("GPL v2");
196 MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
197 MODULE_DESCRIPTION("Qualcomm SMEM NAND flash partition parser");
198