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Diffstat (limited to 'include/log.h')
| -rw-r--r-- | include/log.h | 304 |
1 files changed, 304 insertions, 0 deletions
diff --git a/include/log.h b/include/log.h new file mode 100644 index 0000000000..8083b64831 --- /dev/null +++ b/include/log.h @@ -0,0 +1,304 @@ +/* + * Logging support + * + * Copyright (c) 2017 Google, Inc + * Written by Simon Glass <sjg@chromium.org> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef __LOG_H +#define __LOG_H + +#include <dm/uclass-id.h> +#include <linux/list.h> + +/** Log levels supported, ranging from most to least important */ +enum log_level_t { + LOGL_EMERG = 0, /*U-Boot is unstable */ + LOGL_ALERT, /* Action must be taken immediately */ + LOGL_CRIT, /* Critical conditions */ + LOGL_ERR, /* Error that prevents something from working */ + LOGL_WARNING, /* Warning may prevent optimial operation */ + LOGL_NOTICE, /* Normal but significant condition, printf() */ + LOGL_INFO, /* General information message */ + LOGL_DEBUG, /* Basic debug-level message */ + LOGL_DEBUG_CONTENT, /* Debug message showing full message content */ + LOGL_DEBUG_IO, /* Debug message showing hardware I/O access */ + + LOGL_COUNT, + LOGL_FIRST = LOGL_EMERG, + LOGL_MAX = LOGL_DEBUG, +}; + +/** + * Log categories supported. Most of these correspond to uclasses (i.e. + * enum uclass_id) but there are also some more generic categories + */ +enum log_category_t { + LOGC_FIRST = 0, /* First part mirrors UCLASS_... */ + + LOGC_NONE = UCLASS_COUNT, + LOGC_ARCH, + LOGC_BOARD, + LOGC_CORE, + LOGC_DT, + + LOGC_COUNT, + LOGC_END, +}; + +/* Helper to cast a uclass ID to a log category */ +static inline int log_uc_cat(enum uclass_id id) +{ + return (enum log_category_t)id; +} + +/** + * _log() - Internal function to emit a new log record + * + * @cat: Category of log record (indicating which subsystem generated it) + * @level: Level of log record (indicating its severity) + * @file: File name of file where log record was generated + * @line: Line number in file where log record was generated + * @func: Function where log record was generated + * @fmt: printf() format string for log record + * @...: Optional parameters, according to the format string @fmt + * @return 0 if log record was emitted, -ve on error + */ +int _log(enum log_category_t cat, enum log_level_t level, const char *file, + int line, const char *func, const char *fmt, ...); + +/* Define this at the top of a file to add a prefix to debug messages */ +#ifndef pr_fmt +#define pr_fmt(fmt) fmt +#endif + +/* Use a default category if this file does not supply one */ +#ifndef LOG_CATEGORY +#define LOG_CATEGORY LOGC_NONE +#endif + +/* + * This header may be including when CONFIG_LOG is disabled, in which case + * CONFIG_LOG_MAX_LEVEL is not defined. Add a check for this. + */ +#if CONFIG_IS_ENABLED(LOG) +#define _LOG_MAX_LEVEL CONFIG_VAL(LOG_MAX_LEVEL) +#else +#define _LOG_MAX_LEVEL LOGL_INFO +#endif + +/* Emit a log record if the level is less that the maximum */ +#define log(_cat, _level, _fmt, _args...) ({ \ + int _l = _level; \ + if (_l <= _LOG_MAX_LEVEL) \ + _log((enum log_category_t)(_cat), _l, __FILE__, __LINE__, \ + __func__, \ + pr_fmt(_fmt), ##_args); \ + }) + +#ifdef DEBUG +#define _DEBUG 1 +#else +#define _DEBUG 0 +#endif + +#ifdef CONFIG_SPL_BUILD +#define _SPL_BUILD 1 +#else +#define _SPL_BUILD 0 +#endif + +#if !_DEBUG && CONFIG_IS_ENABLED(LOG) + +#define debug_cond(cond, fmt, args...) \ + do { \ + if (1) \ + log(LOG_CATEGORY, LOGL_DEBUG, fmt, ##args); \ + } while (0) + +#else /* _DEBUG */ + +/* + * Output a debug text when condition "cond" is met. The "cond" should be + * computed by a preprocessor in the best case, allowing for the best + * optimization. + */ +#define debug_cond(cond, fmt, args...) \ + do { \ + if (cond) \ + printf(pr_fmt(fmt), ##args); \ + } while (0) + +#endif /* _DEBUG */ + +/* Show a message if DEBUG is defined in a file */ +#define debug(fmt, args...) \ + debug_cond(_DEBUG, fmt, ##args) + +/* Show a message if not in SPL */ +#define warn_non_spl(fmt, args...) \ + debug_cond(!_SPL_BUILD, fmt, ##args) + +/* + * An assertion is run-time check done in debug mode only. If DEBUG is not + * defined then it is skipped. If DEBUG is defined and the assertion fails, + * then it calls panic*( which may or may not reset/halt U-Boot (see + * CONFIG_PANIC_HANG), It is hoped that all failing assertions are found + * before release, and after release it is hoped that they don't matter. But + * in any case these failing assertions cannot be fixed with a reset (which + * may just do the same assertion again). + */ +void __assert_fail(const char *assertion, const char *file, unsigned int line, + const char *function); +#define assert(x) \ + ({ if (!(x) && _DEBUG) \ + __assert_fail(#x, __FILE__, __LINE__, __func__); }) + +/** + * struct log_rec - a single log record + * + * Holds information about a single record in the log + * + * Members marked as 'not allocated' are stored as pointers and the caller is + * responsible for making sure that the data pointed to is not overwritten. + * Memebers marked as 'allocated' are allocated (e.g. via strdup()) by the log + * system. + * + * @cat: Category, representing a uclass or part of U-Boot + * @level: Severity level, less severe is higher + * @file: Name of file where the log record was generated (not allocated) + * @line: Line number where the log record was generated + * @func: Function where the log record was generated (not allocated) + * @msg: Log message (allocated) + */ +struct log_rec { + enum log_category_t cat; + enum log_level_t level; + const char *file; + int line; + const char *func; + const char *msg; +}; + +struct log_device; + +/** + * struct log_driver - a driver which accepts and processes log records + * + * @name: Name of driver + */ +struct log_driver { + const char *name; + /** + * emit() - emit a log record + * + * Called by the log system to pass a log record to a particular driver + * for processing. The filter is checked before calling this function. + */ + int (*emit)(struct log_device *ldev, struct log_rec *rec); +}; + +/** + * struct log_device - an instance of a log driver + * + * Since drivers are set up at build-time we need to have a separate device for + * the run-time aspects of drivers (currently just a list of filters to apply + * to records send to this device). + * + * @next_filter_num: Seqence number of next filter filter added (0=no filters + * yet). This increments with each new filter on the device, but never + * decrements + * @drv: Pointer to driver for this device + * @filter_head: List of filters for this device + * @sibling_node: Next device in the list of all devices + */ +struct log_device { + int next_filter_num; + struct log_driver *drv; + struct list_head filter_head; + struct list_head sibling_node; +}; + +enum { + LOGF_MAX_CATEGORIES = 5, /* maximum categories per filter */ +}; + +enum log_filter_flags { + LOGFF_HAS_CAT = 1 << 0, /* Filter has a category list */ +}; + +/** + * struct log_filter - criterial to filter out log messages + * + * @filter_num: Sequence number of this filter. This is returned when adding a + * new filter, and must be provided when removing a previously added + * filter. + * @flags: Flags for this filter (LOGFF_...) + * @cat_list: List of categories to allow (terminated by LOGC_none). If empty + * then all categories are permitted. Up to LOGF_MAX_CATEGORIES entries + * can be provided + * @max_level: Maximum log level to allow + * @file_list: List of files to allow, separated by comma. If NULL then all + * files are permitted + * @sibling_node: Next filter in the list of filters for this log device + */ +struct log_filter { + int filter_num; + int flags; + enum log_category_t cat_list[LOGF_MAX_CATEGORIES]; + enum log_level_t max_level; + const char *file_list; + struct list_head sibling_node; +}; + +#define LOG_DRIVER(_name) \ + ll_entry_declare(struct log_driver, _name, log_driver) + +/* Handle the 'log test' command */ +int do_log_test(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[]); + +/** + * log_add_filter() - Add a new filter to a log device + * + * @drv_name: Driver name to add the filter to (since each driver only has a + * single device) + * @cat_list: List of categories to allow (terminated by LOGC_none). If empty + * then all categories are permitted. Up to LOGF_MAX_CATEGORIES entries + * can be provided + * @max_level: Maximum log level to allow + * @file_list: List of files to allow, separated by comma. If NULL then all + * files are permitted + * @return the sequence number of the new filter (>=0) if the filter was added, + * or a -ve value on error + */ +int log_add_filter(const char *drv_name, enum log_category_t cat_list[], + enum log_level_t max_level, const char *file_list); + +/** + * log_remove_filter() - Remove a filter from a log device + * + * @drv_name: Driver name to remove the filter from (since each driver only has + * a single device) + * @filter_num: Filter number to remove (as returned by log_add_filter()) + * @return 0 if the filter was removed, -ENOENT if either the driver or the + * filter number was not found + */ +int log_remove_filter(const char *drv_name, int filter_num); + +#if CONFIG_IS_ENABLED(LOG) +/** + * log_init() - Set up the log system ready for use + * + * @return 0 if OK, -ENOMEM if out of memory + */ +int log_init(void); +#else +static inline int log_init(void) +{ + return 0; +} +#endif + +#endif |