1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* Copyright (c) 2016-2018, The Linux Foundation. All rights reserved. */ 3 4 #include <linux/debugfs.h> 5 #include <linux/kernel.h> 6 #include <linux/of.h> 7 #include <linux/of_address.h> 8 #include <linux/of_reserved_mem.h> 9 #include <linux/platform_device.h> 10 #include <linux/seq_file.h> 11 #include <linux/types.h> 12 13 #include <soc/qcom/cmd-db.h> 14 15 #define NUM_PRIORITY 2 16 #define MAX_SLV_ID 8 17 #define SLAVE_ID_MASK 0x7 18 #define SLAVE_ID_SHIFT 16 19 20 /** 21 * struct entry_header: header for each entry in cmddb 22 * 23 * @id: resource's identifier 24 * @priority: unused 25 * @addr: the address of the resource 26 * @len: length of the data 27 * @offset: offset from :@data_offset, start of the data 28 */ 29 struct entry_header { 30 u8 id[8]; 31 __le32 priority[NUM_PRIORITY]; 32 __le32 addr; 33 __le16 len; 34 __le16 offset; 35 }; 36 37 /** 38 * struct rsc_hdr: resource header information 39 * 40 * @slv_id: id for the resource 41 * @header_offset: entry's header at offset from the end of the cmd_db_header 42 * @data_offset: entry's data at offset from the end of the cmd_db_header 43 * @cnt: number of entries for HW type 44 * @version: MSB is major, LSB is minor 45 * @reserved: reserved for future use. 46 */ 47 struct rsc_hdr { 48 __le16 slv_id; 49 __le16 header_offset; 50 __le16 data_offset; 51 __le16 cnt; 52 __le16 version; 53 __le16 reserved[3]; 54 }; 55 56 /** 57 * struct cmd_db_header: The DB header information 58 * 59 * @version: The cmd db version 60 * @magic: constant expected in the database 61 * @header: array of resources 62 * @checksum: checksum for the header. Unused. 63 * @reserved: reserved memory 64 * @data: driver specific data 65 */ 66 struct cmd_db_header { 67 __le32 version; 68 u8 magic[4]; 69 struct rsc_hdr header[MAX_SLV_ID]; 70 __le32 checksum; 71 __le32 reserved; 72 u8 data[]; 73 }; 74 75 /** 76 * DOC: Description of the Command DB database. 77 * 78 * At the start of the command DB memory is the cmd_db_header structure. 79 * The cmd_db_header holds the version, checksum, magic key as well as an 80 * array for header for each slave (depicted by the rsc_header). Each h/w 81 * based accelerator is a 'slave' (shared resource) and has slave id indicating 82 * the type of accelerator. The rsc_header is the header for such individual 83 * slaves of a given type. The entries for each of these slaves begin at the 84 * rsc_hdr.header_offset. In addition each slave could have auxiliary data 85 * that may be needed by the driver. The data for the slave starts at the 86 * entry_header.offset to the location pointed to by the rsc_hdr.data_offset. 87 * 88 * Drivers have a stringified key to a slave/resource. They can query the slave 89 * information and get the slave id and the auxiliary data and the length of the 90 * data. Using this information, they can format the request to be sent to the 91 * h/w accelerator and request a resource state. 92 */ 93 94 static const u8 CMD_DB_MAGIC[] = { 0xdb, 0x30, 0x03, 0x0c }; 95 96 static bool cmd_db_magic_matches(const struct cmd_db_header *header) 97 { 98 const u8 *magic = header->magic; 99 100 return memcmp(magic, CMD_DB_MAGIC, ARRAY_SIZE(CMD_DB_MAGIC)) == 0; 101 } 102 103 static struct cmd_db_header *cmd_db_header; 104 105 static inline const void *rsc_to_entry_header(const struct rsc_hdr *hdr) 106 { 107 u16 offset = le16_to_cpu(hdr->header_offset); 108 109 return cmd_db_header->data + offset; 110 } 111 112 static inline void * 113 rsc_offset(const struct rsc_hdr *hdr, const struct entry_header *ent) 114 { 115 u16 offset = le16_to_cpu(hdr->data_offset); 116 u16 loffset = le16_to_cpu(ent->offset); 117 118 return cmd_db_header->data + offset + loffset; 119 } 120 121 /** 122 * cmd_db_ready - Indicates if command DB is available 123 * 124 * Return: 0 on success, errno otherwise 125 */ 126 int cmd_db_ready(void) 127 { 128 if (cmd_db_header == NULL) 129 return -EPROBE_DEFER; 130 else if (!cmd_db_magic_matches(cmd_db_header)) 131 return -EINVAL; 132 133 return 0; 134 } 135 EXPORT_SYMBOL(cmd_db_ready); 136 137 static int cmd_db_get_header(const char *id, const struct entry_header **eh, 138 const struct rsc_hdr **rh) 139 { 140 const struct rsc_hdr *rsc_hdr; 141 const struct entry_header *ent; 142 int ret, i, j; 143 u8 query[8]; 144 145 ret = cmd_db_ready(); 146 if (ret) 147 return ret; 148 149 /* Pad out query string to same length as in DB */ 150 strncpy(query, id, sizeof(query)); 151 152 for (i = 0; i < MAX_SLV_ID; i++) { 153 rsc_hdr = &cmd_db_header->header[i]; 154 if (!rsc_hdr->slv_id) 155 break; 156 157 ent = rsc_to_entry_header(rsc_hdr); 158 for (j = 0; j < le16_to_cpu(rsc_hdr->cnt); j++, ent++) { 159 if (memcmp(ent->id, query, sizeof(ent->id)) == 0) { 160 if (eh) 161 *eh = ent; 162 if (rh) 163 *rh = rsc_hdr; 164 return 0; 165 } 166 } 167 } 168 169 return -ENODEV; 170 } 171 172 /** 173 * cmd_db_read_addr() - Query command db for resource id address. 174 * 175 * @id: resource id to query for address 176 * 177 * Return: resource address on success, 0 on error 178 * 179 * This is used to retrieve resource address based on resource 180 * id. 181 */ 182 u32 cmd_db_read_addr(const char *id) 183 { 184 int ret; 185 const struct entry_header *ent; 186 187 ret = cmd_db_get_header(id, &ent, NULL); 188 189 return ret < 0 ? 0 : le32_to_cpu(ent->addr); 190 } 191 EXPORT_SYMBOL(cmd_db_read_addr); 192 193 /** 194 * cmd_db_read_aux_data() - Query command db for aux data. 195 * 196 * @id: Resource to retrieve AUX Data on 197 * @len: size of data buffer returned 198 * 199 * Return: pointer to data on success, error pointer otherwise 200 */ 201 const void *cmd_db_read_aux_data(const char *id, size_t *len) 202 { 203 int ret; 204 const struct entry_header *ent; 205 const struct rsc_hdr *rsc_hdr; 206 207 ret = cmd_db_get_header(id, &ent, &rsc_hdr); 208 if (ret) 209 return ERR_PTR(ret); 210 211 if (len) 212 *len = le16_to_cpu(ent->len); 213 214 return rsc_offset(rsc_hdr, ent); 215 } 216 EXPORT_SYMBOL(cmd_db_read_aux_data); 217 218 /** 219 * cmd_db_read_slave_id - Get the slave ID for a given resource address 220 * 221 * @id: Resource id to query the DB for version 222 * 223 * Return: cmd_db_hw_type enum on success, CMD_DB_HW_INVALID on error 224 */ 225 enum cmd_db_hw_type cmd_db_read_slave_id(const char *id) 226 { 227 int ret; 228 const struct entry_header *ent; 229 u32 addr; 230 231 ret = cmd_db_get_header(id, &ent, NULL); 232 if (ret < 0) 233 return CMD_DB_HW_INVALID; 234 235 addr = le32_to_cpu(ent->addr); 236 return (addr >> SLAVE_ID_SHIFT) & SLAVE_ID_MASK; 237 } 238 EXPORT_SYMBOL(cmd_db_read_slave_id); 239 240 #ifdef CONFIG_DEBUG_FS 241 static int cmd_db_debugfs_dump(struct seq_file *seq, void *p) 242 { 243 int i, j; 244 const struct rsc_hdr *rsc; 245 const struct entry_header *ent; 246 const char *name; 247 u16 len, version; 248 u8 major, minor; 249 250 seq_puts(seq, "Command DB DUMP\n"); 251 252 for (i = 0; i < MAX_SLV_ID; i++) { 253 rsc = &cmd_db_header->header[i]; 254 if (!rsc->slv_id) 255 break; 256 257 switch (le16_to_cpu(rsc->slv_id)) { 258 case CMD_DB_HW_ARC: 259 name = "ARC"; 260 break; 261 case CMD_DB_HW_VRM: 262 name = "VRM"; 263 break; 264 case CMD_DB_HW_BCM: 265 name = "BCM"; 266 break; 267 default: 268 name = "Unknown"; 269 break; 270 } 271 272 version = le16_to_cpu(rsc->version); 273 major = version >> 8; 274 minor = version; 275 276 seq_printf(seq, "Slave %s (v%u.%u)\n", name, major, minor); 277 seq_puts(seq, "-------------------------\n"); 278 279 ent = rsc_to_entry_header(rsc); 280 for (j = 0; j < le16_to_cpu(rsc->cnt); j++, ent++) { 281 seq_printf(seq, "0x%05x: %*pEp", le32_to_cpu(ent->addr), 282 (int)sizeof(ent->id), ent->id); 283 284 len = le16_to_cpu(ent->len); 285 if (len) { 286 seq_printf(seq, " [%*ph]", 287 len, rsc_offset(rsc, ent)); 288 } 289 seq_putc(seq, '\n'); 290 } 291 } 292 293 return 0; 294 } 295 296 static int open_cmd_db_debugfs(struct inode *inode, struct file *file) 297 { 298 return single_open(file, cmd_db_debugfs_dump, inode->i_private); 299 } 300 #endif 301 302 static const struct file_operations cmd_db_debugfs_ops = { 303 #ifdef CONFIG_DEBUG_FS 304 .open = open_cmd_db_debugfs, 305 #endif 306 .read = seq_read, 307 .llseek = seq_lseek, 308 .release = single_release, 309 }; 310 311 static int cmd_db_dev_probe(struct platform_device *pdev) 312 { 313 struct reserved_mem *rmem; 314 int ret = 0; 315 316 rmem = of_reserved_mem_lookup(pdev->dev.of_node); 317 if (!rmem) { 318 dev_err(&pdev->dev, "failed to acquire memory region\n"); 319 return -EINVAL; 320 } 321 322 cmd_db_header = memremap(rmem->base, rmem->size, MEMREMAP_WB); 323 if (!cmd_db_header) { 324 ret = -ENOMEM; 325 cmd_db_header = NULL; 326 return ret; 327 } 328 329 if (!cmd_db_magic_matches(cmd_db_header)) { 330 dev_err(&pdev->dev, "Invalid Command DB Magic\n"); 331 return -EINVAL; 332 } 333 334 debugfs_create_file("cmd-db", 0400, NULL, NULL, &cmd_db_debugfs_ops); 335 336 return 0; 337 } 338 339 static const struct of_device_id cmd_db_match_table[] = { 340 { .compatible = "qcom,cmd-db" }, 341 { } 342 }; 343 344 static struct platform_driver cmd_db_dev_driver = { 345 .probe = cmd_db_dev_probe, 346 .driver = { 347 .name = "cmd-db", 348 .of_match_table = cmd_db_match_table, 349 }, 350 }; 351 352 static int __init cmd_db_device_init(void) 353 { 354 return platform_driver_register(&cmd_db_dev_driver); 355 } 356 arch_initcall(cmd_db_device_init); 357