1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* Copyright (c) 2016-2018, 2020, The Linux Foundation. All rights reserved. */ 3 4 #include <linux/debugfs.h> 5 #include <linux/kernel.h> 6 #include <linux/module.h> 7 #include <linux/of.h> 8 #include <linux/of_address.h> 9 #include <linux/of_reserved_mem.h> 10 #include <linux/platform_device.h> 11 #include <linux/seq_file.h> 12 #include <linux/types.h> 13 14 #include <soc/qcom/cmd-db.h> 15 16 #define NUM_PRIORITY 2 17 #define MAX_SLV_ID 8 18 #define SLAVE_ID_MASK 0x7 19 #define SLAVE_ID_SHIFT 16 20 21 /** 22 * struct entry_header: header for each entry in cmddb 23 * 24 * @id: resource's identifier 25 * @priority: unused 26 * @addr: the address of the resource 27 * @len: length of the data 28 * @offset: offset from :@data_offset, start of the data 29 */ 30 struct entry_header { 31 u8 id[8]; 32 __le32 priority[NUM_PRIORITY]; 33 __le32 addr; 34 __le16 len; 35 __le16 offset; 36 }; 37 38 /** 39 * struct rsc_hdr: resource header information 40 * 41 * @slv_id: id for the resource 42 * @header_offset: entry's header at offset from the end of the cmd_db_header 43 * @data_offset: entry's data at offset from the end of the cmd_db_header 44 * @cnt: number of entries for HW type 45 * @version: MSB is major, LSB is minor 46 * @reserved: reserved for future use. 47 */ 48 struct rsc_hdr { 49 __le16 slv_id; 50 __le16 header_offset; 51 __le16 data_offset; 52 __le16 cnt; 53 __le16 version; 54 __le16 reserved[3]; 55 }; 56 57 /** 58 * struct cmd_db_header: The DB header information 59 * 60 * @version: The cmd db version 61 * @magic: constant expected in the database 62 * @header: array of resources 63 * @checksum: checksum for the header. Unused. 64 * @reserved: reserved memory 65 * @data: driver specific data 66 */ 67 struct cmd_db_header { 68 __le32 version; 69 u8 magic[4]; 70 struct rsc_hdr header[MAX_SLV_ID]; 71 __le32 checksum; 72 __le32 reserved; 73 u8 data[]; 74 }; 75 76 /** 77 * DOC: Description of the Command DB database. 78 * 79 * At the start of the command DB memory is the cmd_db_header structure. 80 * The cmd_db_header holds the version, checksum, magic key as well as an 81 * array for header for each slave (depicted by the rsc_header). Each h/w 82 * based accelerator is a 'slave' (shared resource) and has slave id indicating 83 * the type of accelerator. The rsc_header is the header for such individual 84 * slaves of a given type. The entries for each of these slaves begin at the 85 * rsc_hdr.header_offset. In addition each slave could have auxiliary data 86 * that may be needed by the driver. The data for the slave starts at the 87 * entry_header.offset to the location pointed to by the rsc_hdr.data_offset. 88 * 89 * Drivers have a stringified key to a slave/resource. They can query the slave 90 * information and get the slave id and the auxiliary data and the length of the 91 * data. Using this information, they can format the request to be sent to the 92 * h/w accelerator and request a resource state. 93 */ 94 95 static const u8 CMD_DB_MAGIC[] = { 0xdb, 0x30, 0x03, 0x0c }; 96 97 static bool cmd_db_magic_matches(const struct cmd_db_header *header) 98 { 99 const u8 *magic = header->magic; 100 101 return memcmp(magic, CMD_DB_MAGIC, ARRAY_SIZE(CMD_DB_MAGIC)) == 0; 102 } 103 104 static struct cmd_db_header *cmd_db_header; 105 106 static inline const void *rsc_to_entry_header(const struct rsc_hdr *hdr) 107 { 108 u16 offset = le16_to_cpu(hdr->header_offset); 109 110 return cmd_db_header->data + offset; 111 } 112 113 static inline void * 114 rsc_offset(const struct rsc_hdr *hdr, const struct entry_header *ent) 115 { 116 u16 offset = le16_to_cpu(hdr->data_offset); 117 u16 loffset = le16_to_cpu(ent->offset); 118 119 return cmd_db_header->data + offset + loffset; 120 } 121 122 /** 123 * cmd_db_ready - Indicates if command DB is available 124 * 125 * Return: 0 on success, errno otherwise 126 */ 127 int cmd_db_ready(void) 128 { 129 if (cmd_db_header == NULL) 130 return -EPROBE_DEFER; 131 else if (!cmd_db_magic_matches(cmd_db_header)) 132 return -EINVAL; 133 134 return 0; 135 } 136 EXPORT_SYMBOL(cmd_db_ready); 137 138 static int cmd_db_get_header(const char *id, const struct entry_header **eh, 139 const struct rsc_hdr **rh) 140 { 141 const struct rsc_hdr *rsc_hdr; 142 const struct entry_header *ent; 143 int ret, i, j; 144 u8 query[sizeof(ent->id)] __nonstring; 145 146 ret = cmd_db_ready(); 147 if (ret) 148 return ret; 149 150 /* 151 * Pad out query string to same length as in DB. NOTE: the output 152 * query string is not necessarily '\0' terminated if it bumps up 153 * against the max size. That's OK and expected. 154 */ 155 strncpy(query, id, sizeof(query)); 156 157 for (i = 0; i < MAX_SLV_ID; i++) { 158 rsc_hdr = &cmd_db_header->header[i]; 159 if (!rsc_hdr->slv_id) 160 break; 161 162 ent = rsc_to_entry_header(rsc_hdr); 163 for (j = 0; j < le16_to_cpu(rsc_hdr->cnt); j++, ent++) { 164 if (memcmp(ent->id, query, sizeof(ent->id)) == 0) { 165 if (eh) 166 *eh = ent; 167 if (rh) 168 *rh = rsc_hdr; 169 return 0; 170 } 171 } 172 } 173 174 return -ENODEV; 175 } 176 177 /** 178 * cmd_db_read_addr() - Query command db for resource id address. 179 * 180 * @id: resource id to query for address 181 * 182 * Return: resource address on success, 0 on error 183 * 184 * This is used to retrieve resource address based on resource 185 * id. 186 */ 187 u32 cmd_db_read_addr(const char *id) 188 { 189 int ret; 190 const struct entry_header *ent; 191 192 ret = cmd_db_get_header(id, &ent, NULL); 193 194 return ret < 0 ? 0 : le32_to_cpu(ent->addr); 195 } 196 EXPORT_SYMBOL(cmd_db_read_addr); 197 198 /** 199 * cmd_db_read_aux_data() - Query command db for aux data. 200 * 201 * @id: Resource to retrieve AUX Data on 202 * @len: size of data buffer returned 203 * 204 * Return: pointer to data on success, error pointer otherwise 205 */ 206 const void *cmd_db_read_aux_data(const char *id, size_t *len) 207 { 208 int ret; 209 const struct entry_header *ent; 210 const struct rsc_hdr *rsc_hdr; 211 212 ret = cmd_db_get_header(id, &ent, &rsc_hdr); 213 if (ret) 214 return ERR_PTR(ret); 215 216 if (len) 217 *len = le16_to_cpu(ent->len); 218 219 return rsc_offset(rsc_hdr, ent); 220 } 221 EXPORT_SYMBOL(cmd_db_read_aux_data); 222 223 /** 224 * cmd_db_read_slave_id - Get the slave ID for a given resource address 225 * 226 * @id: Resource id to query the DB for version 227 * 228 * Return: cmd_db_hw_type enum on success, CMD_DB_HW_INVALID on error 229 */ 230 enum cmd_db_hw_type cmd_db_read_slave_id(const char *id) 231 { 232 int ret; 233 const struct entry_header *ent; 234 u32 addr; 235 236 ret = cmd_db_get_header(id, &ent, NULL); 237 if (ret < 0) 238 return CMD_DB_HW_INVALID; 239 240 addr = le32_to_cpu(ent->addr); 241 return (addr >> SLAVE_ID_SHIFT) & SLAVE_ID_MASK; 242 } 243 EXPORT_SYMBOL(cmd_db_read_slave_id); 244 245 #ifdef CONFIG_DEBUG_FS 246 static int cmd_db_debugfs_dump(struct seq_file *seq, void *p) 247 { 248 int i, j; 249 const struct rsc_hdr *rsc; 250 const struct entry_header *ent; 251 const char *name; 252 u16 len, version; 253 u8 major, minor; 254 255 seq_puts(seq, "Command DB DUMP\n"); 256 257 for (i = 0; i < MAX_SLV_ID; i++) { 258 rsc = &cmd_db_header->header[i]; 259 if (!rsc->slv_id) 260 break; 261 262 switch (le16_to_cpu(rsc->slv_id)) { 263 case CMD_DB_HW_ARC: 264 name = "ARC"; 265 break; 266 case CMD_DB_HW_VRM: 267 name = "VRM"; 268 break; 269 case CMD_DB_HW_BCM: 270 name = "BCM"; 271 break; 272 default: 273 name = "Unknown"; 274 break; 275 } 276 277 version = le16_to_cpu(rsc->version); 278 major = version >> 8; 279 minor = version; 280 281 seq_printf(seq, "Slave %s (v%u.%u)\n", name, major, minor); 282 seq_puts(seq, "-------------------------\n"); 283 284 ent = rsc_to_entry_header(rsc); 285 for (j = 0; j < le16_to_cpu(rsc->cnt); j++, ent++) { 286 seq_printf(seq, "0x%05x: %*pEp", le32_to_cpu(ent->addr), 287 (int)sizeof(ent->id), ent->id); 288 289 len = le16_to_cpu(ent->len); 290 if (len) { 291 seq_printf(seq, " [%*ph]", 292 len, rsc_offset(rsc, ent)); 293 } 294 seq_putc(seq, '\n'); 295 } 296 } 297 298 return 0; 299 } 300 301 static int open_cmd_db_debugfs(struct inode *inode, struct file *file) 302 { 303 return single_open(file, cmd_db_debugfs_dump, inode->i_private); 304 } 305 #endif 306 307 static const struct file_operations cmd_db_debugfs_ops = { 308 #ifdef CONFIG_DEBUG_FS 309 .open = open_cmd_db_debugfs, 310 #endif 311 .read = seq_read, 312 .llseek = seq_lseek, 313 .release = single_release, 314 }; 315 316 static int cmd_db_dev_probe(struct platform_device *pdev) 317 { 318 struct reserved_mem *rmem; 319 int ret = 0; 320 321 rmem = of_reserved_mem_lookup(pdev->dev.of_node); 322 if (!rmem) { 323 dev_err(&pdev->dev, "failed to acquire memory region\n"); 324 return -EINVAL; 325 } 326 327 cmd_db_header = memremap(rmem->base, rmem->size, MEMREMAP_WB); 328 if (!cmd_db_header) { 329 ret = -ENOMEM; 330 cmd_db_header = NULL; 331 return ret; 332 } 333 334 if (!cmd_db_magic_matches(cmd_db_header)) { 335 dev_err(&pdev->dev, "Invalid Command DB Magic\n"); 336 return -EINVAL; 337 } 338 339 debugfs_create_file("cmd-db", 0400, NULL, NULL, &cmd_db_debugfs_ops); 340 341 device_set_pm_not_required(&pdev->dev); 342 343 return 0; 344 } 345 346 static const struct of_device_id cmd_db_match_table[] = { 347 { .compatible = "qcom,cmd-db" }, 348 { } 349 }; 350 MODULE_DEVICE_TABLE(of, cmd_db_match_table); 351 352 static struct platform_driver cmd_db_dev_driver = { 353 .probe = cmd_db_dev_probe, 354 .driver = { 355 .name = "cmd-db", 356 .of_match_table = cmd_db_match_table, 357 .suppress_bind_attrs = true, 358 }, 359 }; 360 361 static int __init cmd_db_device_init(void) 362 { 363 return platform_driver_register(&cmd_db_dev_driver); 364 } 365 arch_initcall(cmd_db_device_init); 366 367 MODULE_DESCRIPTION("Qualcomm Technologies, Inc. Command DB Driver"); 368 MODULE_LICENSE("GPL v2"); 369