1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * Logging support 4 * 5 * Copyright (c) 2017 Google, Inc 6 * Written by Simon Glass <sjg (at) chromium.org> 7 */ 8 9 #ifndef __LOG_H 10 #define __LOG_H 11 12 #include <dm/uclass-id.h> 13 #include <linux/list.h> 14 15 /** Log levels supported, ranging from most to least important */ 16 enum log_level_t { 17 LOGL_EMERG = 0, /*U-Boot is unstable */ 18 LOGL_ALERT, /* Action must be taken immediately */ 19 LOGL_CRIT, /* Critical conditions */ 20 LOGL_ERR, /* Error that prevents something from working */ 21 LOGL_WARNING, /* Warning may prevent optimial operation */ 22 LOGL_NOTICE, /* Normal but significant condition, printf() */ 23 LOGL_INFO, /* General information message */ 24 LOGL_DEBUG, /* Basic debug-level message */ 25 LOGL_DEBUG_CONTENT, /* Debug message showing full message content */ 26 LOGL_DEBUG_IO, /* Debug message showing hardware I/O access */ 27 28 LOGL_COUNT, 29 LOGL_NONE, 30 31 LOGL_FIRST = LOGL_EMERG, 32 LOGL_MAX = LOGL_DEBUG_IO, 33 }; 34 35 /** 36 * Log categories supported. Most of these correspond to uclasses (i.e. 37 * enum uclass_id) but there are also some more generic categories 38 */ 39 enum log_category_t { 40 LOGC_FIRST = 0, /* First part mirrors UCLASS_... */ 41 42 LOGC_NONE = UCLASS_COUNT, 43 LOGC_ARCH, 44 LOGC_BOARD, 45 LOGC_CORE, 46 LOGC_DM, /* Core driver-model */ 47 LOGC_DT, /* Device-tree */ 48 LOGC_EFI, /* EFI implementation */ 49 50 LOGC_COUNT, 51 LOGC_END, 52 }; 53 54 /* Helper to cast a uclass ID to a log category */ 55 static inline int log_uc_cat(enum uclass_id id) 56 { 57 return (enum log_category_t)id; 58 } 59 60 /** 61 * _log() - Internal function to emit a new log record 62 * 63 * @cat: Category of log record (indicating which subsystem generated it) 64 * @level: Level of log record (indicating its severity) 65 * @file: File name of file where log record was generated 66 * @line: Line number in file where log record was generated 67 * @func: Function where log record was generated 68 * @fmt: printf() format string for log record 69 * @...: Optional parameters, according to the format string @fmt 70 * @return 0 if log record was emitted, -ve on error 71 */ 72 int _log(enum log_category_t cat, enum log_level_t level, const char *file, 73 int line, const char *func, const char *fmt, ...); 74 75 /* Define this at the top of a file to add a prefix to debug messages */ 76 #ifndef pr_fmt 77 #define pr_fmt(fmt) fmt 78 #endif 79 80 /* Use a default category if this file does not supply one */ 81 #ifndef LOG_CATEGORY 82 #define LOG_CATEGORY LOGC_NONE 83 #endif 84 85 /* 86 * This header may be including when CONFIG_LOG is disabled, in which case 87 * CONFIG_LOG_MAX_LEVEL is not defined. Add a check for this. 88 */ 89 #if CONFIG_IS_ENABLED(LOG) 90 #define _LOG_MAX_LEVEL CONFIG_VAL(LOG_MAX_LEVEL) 91 #else 92 #define _LOG_MAX_LEVEL LOGL_INFO 93 #endif 94 95 /* Emit a log record if the level is less that the maximum */ 96 #define log(_cat, _level, _fmt, _args...) ({ \ 97 int _l = _level; \ 98 if (_l <= _LOG_MAX_LEVEL) \ 99 _log((enum log_category_t)(_cat), _l, __FILE__, __LINE__, \ 100 __func__, \ 101 pr_fmt(_fmt), ##_args); \ 102 }) 103 104 #ifdef DEBUG 105 #define _DEBUG 1 106 #else 107 #define _DEBUG 0 108 #endif 109 110 #ifdef CONFIG_SPL_BUILD 111 #define _SPL_BUILD 1 112 #else 113 #define _SPL_BUILD 0 114 #endif 115 116 #if !_DEBUG && CONFIG_IS_ENABLED(LOG) 117 118 #define debug_cond(cond, fmt, args...) \ 119 do { \ 120 if (1) \ 121 log(LOG_CATEGORY, LOGL_DEBUG, fmt, ##args); \ 122 } while (0) 123 124 #else /* _DEBUG */ 125 126 /* 127 * Output a debug text when condition "cond" is met. The "cond" should be 128 * computed by a preprocessor in the best case, allowing for the best 129 * optimization. 130 */ 131 #define debug_cond(cond, fmt, args...) \ 132 do { \ 133 if (cond) \ 134 printf(pr_fmt(fmt), ##args); \ 135 } while (0) 136 137 #endif /* _DEBUG */ 138 139 /* Show a message if DEBUG is defined in a file */ 140 #define debug(fmt, args...) \ 141 debug_cond(_DEBUG, fmt, ##args) 142 143 /* Show a message if not in SPL */ 144 #define warn_non_spl(fmt, args...) \ 145 debug_cond(!_SPL_BUILD, fmt, ##args) 146 147 /* 148 * An assertion is run-time check done in debug mode only. If DEBUG is not 149 * defined then it is skipped. If DEBUG is defined and the assertion fails, 150 * then it calls panic*( which may or may not reset/halt U-Boot (see 151 * CONFIG_PANIC_HANG), It is hoped that all failing assertions are found 152 * before release, and after release it is hoped that they don't matter. But 153 * in any case these failing assertions cannot be fixed with a reset (which 154 * may just do the same assertion again). 155 */ 156 void __assert_fail(const char *assertion, const char *file, unsigned int line, 157 const char *function); 158 #define assert(x) \ 159 ({ if (!(x) && _DEBUG) \ 160 __assert_fail(#x, __FILE__, __LINE__, __func__); }) 161 162 #ifdef CONFIG_LOG_ERROR_RETURN 163 #define log_ret(_ret) ({ \ 164 int __ret = (_ret); \ 165 if (__ret < 0) \ 166 log(LOG_CATEGORY, LOGL_ERR, "returning err=%d\n", __ret); \ 167 __ret; \ 168 }) 169 #else 170 #define log_ret(_ret) (_ret) 171 #endif 172 173 /** 174 * struct log_rec - a single log record 175 * 176 * Holds information about a single record in the log 177 * 178 * Members marked as 'not allocated' are stored as pointers and the caller is 179 * responsible for making sure that the data pointed to is not overwritten. 180 * Memebers marked as 'allocated' are allocated (e.g. via strdup()) by the log 181 * system. 182 * 183 * @cat: Category, representing a uclass or part of U-Boot 184 * @level: Severity level, less severe is higher 185 * @file: Name of file where the log record was generated (not allocated) 186 * @line: Line number where the log record was generated 187 * @func: Function where the log record was generated (not allocated) 188 * @msg: Log message (allocated) 189 */ 190 struct log_rec { 191 enum log_category_t cat; 192 enum log_level_t level; 193 const char *file; 194 int line; 195 const char *func; 196 const char *msg; 197 }; 198 199 struct log_device; 200 201 /** 202 * struct log_driver - a driver which accepts and processes log records 203 * 204 * @name: Name of driver 205 */ 206 struct log_driver { 207 const char *name; 208 /** 209 * emit() - emit a log record 210 * 211 * Called by the log system to pass a log record to a particular driver 212 * for processing. The filter is checked before calling this function. 213 */ 214 int (*emit)(struct log_device *ldev, struct log_rec *rec); 215 }; 216 217 /** 218 * struct log_device - an instance of a log driver 219 * 220 * Since drivers are set up at build-time we need to have a separate device for 221 * the run-time aspects of drivers (currently just a list of filters to apply 222 * to records send to this device). 223 * 224 * @next_filter_num: Seqence number of next filter filter added (0=no filters 225 * yet). This increments with each new filter on the device, but never 226 * decrements 227 * @drv: Pointer to driver for this device 228 * @filter_head: List of filters for this device 229 * @sibling_node: Next device in the list of all devices 230 */ 231 struct log_device { 232 int next_filter_num; 233 struct log_driver *drv; 234 struct list_head filter_head; 235 struct list_head sibling_node; 236 }; 237 238 enum { 239 LOGF_MAX_CATEGORIES = 5, /* maximum categories per filter */ 240 }; 241 242 enum log_filter_flags { 243 LOGFF_HAS_CAT = 1 << 0, /* Filter has a category list */ 244 }; 245 246 /** 247 * struct log_filter - criterial to filter out log messages 248 * 249 * @filter_num: Sequence number of this filter. This is returned when adding a 250 * new filter, and must be provided when removing a previously added 251 * filter. 252 * @flags: Flags for this filter (LOGFF_...) 253 * @cat_list: List of categories to allow (terminated by LOGC_none). If empty 254 * then all categories are permitted. Up to LOGF_MAX_CATEGORIES entries 255 * can be provided 256 * @max_level: Maximum log level to allow 257 * @file_list: List of files to allow, separated by comma. If NULL then all 258 * files are permitted 259 * @sibling_node: Next filter in the list of filters for this log device 260 */ 261 struct log_filter { 262 int filter_num; 263 int flags; 264 enum log_category_t cat_list[LOGF_MAX_CATEGORIES]; 265 enum log_level_t max_level; 266 const char *file_list; 267 struct list_head sibling_node; 268 }; 269 270 #define LOG_DRIVER(_name) \ 271 ll_entry_declare(struct log_driver, _name, log_driver) 272 273 /** 274 * log_get_cat_name() - Get the name of a category 275 * 276 * @cat: Category to look up 277 * @return category name (which may be a uclass driver name) if found, or 278 * "<invalid>" if invalid, or "<missing>" if not found 279 */ 280 const char *log_get_cat_name(enum log_category_t cat); 281 282 /** 283 * log_get_cat_by_name() - Look up a category by name 284 * 285 * @name: Name to look up 286 * @return category ID, or LOGC_NONE if not found 287 */ 288 enum log_category_t log_get_cat_by_name(const char *name); 289 290 /** 291 * log_get_level_name() - Get the name of a log level 292 * 293 * @level: Log level to look up 294 * @return log level name (in ALL CAPS) 295 */ 296 const char *log_get_level_name(enum log_level_t level); 297 298 /** 299 * log_get_level_by_name() - Look up a log level by name 300 * 301 * @name: Name to look up 302 * @return log level ID, or LOGL_NONE if not found 303 */ 304 enum log_level_t log_get_level_by_name(const char *name); 305 306 /* Log format flags (bit numbers) for gd->log_fmt. See log_fmt_chars */ 307 enum log_fmt { 308 LOGF_CAT = 0, 309 LOGF_LEVEL, 310 LOGF_FILE, 311 LOGF_LINE, 312 LOGF_FUNC, 313 LOGF_MSG, 314 315 LOGF_COUNT, 316 LOGF_DEFAULT = (1 << LOGF_FUNC) | (1 << LOGF_MSG), 317 LOGF_ALL = 0x3f, 318 }; 319 320 /* Handle the 'log test' command */ 321 int do_log_test(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[]); 322 323 /** 324 * log_add_filter() - Add a new filter to a log device 325 * 326 * @drv_name: Driver name to add the filter to (since each driver only has a 327 * single device) 328 * @cat_list: List of categories to allow (terminated by LOGC_none). If empty 329 * then all categories are permitted. Up to LOGF_MAX_CATEGORIES entries 330 * can be provided 331 * @max_level: Maximum log level to allow 332 * @file_list: List of files to allow, separated by comma. If NULL then all 333 * files are permitted 334 * @return the sequence number of the new filter (>=0) if the filter was added, 335 * or a -ve value on error 336 */ 337 int log_add_filter(const char *drv_name, enum log_category_t cat_list[], 338 enum log_level_t max_level, const char *file_list); 339 340 /** 341 * log_remove_filter() - Remove a filter from a log device 342 * 343 * @drv_name: Driver name to remove the filter from (since each driver only has 344 * a single device) 345 * @filter_num: Filter number to remove (as returned by log_add_filter()) 346 * @return 0 if the filter was removed, -ENOENT if either the driver or the 347 * filter number was not found 348 */ 349 int log_remove_filter(const char *drv_name, int filter_num); 350 351 #if CONFIG_IS_ENABLED(LOG) 352 /** 353 * log_init() - Set up the log system ready for use 354 * 355 * @return 0 if OK, -ENOMEM if out of memory 356 */ 357 int log_init(void); 358 #else 359 static inline int log_init(void) 360 { 361 return 0; 362 } 363 #endif 364 365 #endif 366
