1 /* 2 * Logging support 3 * 4 * Copyright (c) 2017 Google, Inc 5 * Written by Simon Glass <sjg@chromium.org> 6 * 7 * SPDX-License-Identifier: GPL-2.0+ 8 */ 9 10 #ifndef __LOG_H 11 #define __LOG_H 12 13 #include <dm/uclass-id.h> 14 #include <linux/list.h> 15 16 /** Log levels supported, ranging from most to least important */ 17 enum log_level_t { 18 LOGL_EMERG = 0, /*U-Boot is unstable */ 19 LOGL_ALERT, /* Action must be taken immediately */ 20 LOGL_CRIT, /* Critical conditions */ 21 LOGL_ERR, /* Error that prevents something from working */ 22 LOGL_WARNING, /* Warning may prevent optimial operation */ 23 LOGL_NOTICE, /* Normal but significant condition, printf() */ 24 LOGL_INFO, /* General information message */ 25 LOGL_DEBUG, /* Basic debug-level message */ 26 LOGL_DEBUG_CONTENT, /* Debug message showing full message content */ 27 LOGL_DEBUG_IO, /* Debug message showing hardware I/O access */ 28 29 LOGL_COUNT, 30 LOGL_FIRST = LOGL_EMERG, 31 LOGL_MAX = LOGL_DEBUG, 32 }; 33 34 /** 35 * Log categories supported. Most of these correspond to uclasses (i.e. 36 * enum uclass_id) but there are also some more generic categories 37 */ 38 enum log_category_t { 39 LOGC_FIRST = 0, /* First part mirrors UCLASS_... */ 40 41 LOGC_NONE = UCLASS_COUNT, 42 LOGC_ARCH, 43 LOGC_BOARD, 44 LOGC_CORE, 45 LOGC_DM, /* Core driver-model */ 46 LOGC_DT, /* Device-tree */ 47 LOGC_EFI, /* EFI implementation */ 48 LOGC_ALLOC, /* Memory allocation */ 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 /** 163 * struct log_rec - a single log record 164 * 165 * Holds information about a single record in the log 166 * 167 * Members marked as 'not allocated' are stored as pointers and the caller is 168 * responsible for making sure that the data pointed to is not overwritten. 169 * Memebers marked as 'allocated' are allocated (e.g. via strdup()) by the log 170 * system. 171 * 172 * @cat: Category, representing a uclass or part of U-Boot 173 * @level: Severity level, less severe is higher 174 * @file: Name of file where the log record was generated (not allocated) 175 * @line: Line number where the log record was generated 176 * @func: Function where the log record was generated (not allocated) 177 * @msg: Log message (allocated) 178 */ 179 struct log_rec { 180 enum log_category_t cat; 181 enum log_level_t level; 182 const char *file; 183 int line; 184 const char *func; 185 const char *msg; 186 }; 187 188 struct log_device; 189 190 /** 191 * struct log_driver - a driver which accepts and processes log records 192 * 193 * @name: Name of driver 194 */ 195 struct log_driver { 196 const char *name; 197 /** 198 * emit() - emit a log record 199 * 200 * Called by the log system to pass a log record to a particular driver 201 * for processing. The filter is checked before calling this function. 202 */ 203 int (*emit)(struct log_device *ldev, struct log_rec *rec); 204 }; 205 206 /** 207 * struct log_device - an instance of a log driver 208 * 209 * Since drivers are set up at build-time we need to have a separate device for 210 * the run-time aspects of drivers (currently just a list of filters to apply 211 * to records send to this device). 212 * 213 * @next_filter_num: Seqence number of next filter filter added (0=no filters 214 * yet). This increments with each new filter on the device, but never 215 * decrements 216 * @drv: Pointer to driver for this device 217 * @filter_head: List of filters for this device 218 * @sibling_node: Next device in the list of all devices 219 */ 220 struct log_device { 221 int next_filter_num; 222 struct log_driver *drv; 223 struct list_head filter_head; 224 struct list_head sibling_node; 225 }; 226 227 enum { 228 LOGF_MAX_CATEGORIES = 5, /* maximum categories per filter */ 229 }; 230 231 enum log_filter_flags { 232 LOGFF_HAS_CAT = 1 << 0, /* Filter has a category list */ 233 }; 234 235 /** 236 * struct log_filter - criterial to filter out log messages 237 * 238 * @filter_num: Sequence number of this filter. This is returned when adding a 239 * new filter, and must be provided when removing a previously added 240 * filter. 241 * @flags: Flags for this filter (LOGFF_...) 242 * @cat_list: List of categories to allow (terminated by LOGC_none). If empty 243 * then all categories are permitted. Up to LOGF_MAX_CATEGORIES entries 244 * can be provided 245 * @max_level: Maximum log level to allow 246 * @file_list: List of files to allow, separated by comma. If NULL then all 247 * files are permitted 248 * @sibling_node: Next filter in the list of filters for this log device 249 */ 250 struct log_filter { 251 int filter_num; 252 int flags; 253 enum log_category_t cat_list[LOGF_MAX_CATEGORIES]; 254 enum log_level_t max_level; 255 const char *file_list; 256 struct list_head sibling_node; 257 }; 258 259 #define LOG_DRIVER(_name) \ 260 ll_entry_declare(struct log_driver, _name, log_driver) 261 262 /* Handle the 'log test' command */ 263 int do_log_test(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[]); 264 265 /** 266 * log_add_filter() - Add a new filter to a log device 267 * 268 * @drv_name: Driver name to add the filter to (since each driver only has a 269 * single device) 270 * @cat_list: List of categories to allow (terminated by LOGC_none). If empty 271 * then all categories are permitted. Up to LOGF_MAX_CATEGORIES entries 272 * can be provided 273 * @max_level: Maximum log level to allow 274 * @file_list: List of files to allow, separated by comma. If NULL then all 275 * files are permitted 276 * @return the sequence number of the new filter (>=0) if the filter was added, 277 * or a -ve value on error 278 */ 279 int log_add_filter(const char *drv_name, enum log_category_t cat_list[], 280 enum log_level_t max_level, const char *file_list); 281 282 /** 283 * log_remove_filter() - Remove a filter from a log device 284 * 285 * @drv_name: Driver name to remove the filter from (since each driver only has 286 * a single device) 287 * @filter_num: Filter number to remove (as returned by log_add_filter()) 288 * @return 0 if the filter was removed, -ENOENT if either the driver or the 289 * filter number was not found 290 */ 291 int log_remove_filter(const char *drv_name, int filter_num); 292 293 #if CONFIG_IS_ENABLED(LOG) 294 /** 295 * log_init() - Set up the log system ready for use 296 * 297 * @return 0 if OK, -ENOMEM if out of memory 298 */ 299 int log_init(void); 300 #else 301 static inline int log_init(void) 302 { 303 return 0; 304 } 305 #endif 306 307 #endif 308