+/* SPDX-License-Identifier: GPL-2.0+ */
/*
* 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_NONE,
+
+ LOGL_FIRST = LOGL_EMERG,
+ LOGL_MAX = LOGL_DEBUG_IO,
+};
+
+/**
+ * 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_DM, /* Core driver-model */
+ LOGC_DT, /* Device-tree */
+ LOGC_EFI, /* EFI implementation */
+
+ 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 _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
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)
({ if (!(x) && _DEBUG) \
__assert_fail(#x, __FILE__, __LINE__, __func__); })
+#ifdef CONFIG_LOG_ERROR_RETURN
+#define log_ret(_ret) ({ \
+ int __ret = (_ret); \
+ if (__ret < 0) \
+ log(LOG_CATEGORY, LOGL_ERR, "returning err=%d\n", __ret); \
+ __ret; \
+ })
+#else
+#define log_ret(_ret) (_ret)
+#endif
+
+/**
+ * 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)
+
+/**
+ * log_get_cat_name() - Get the name of a category
+ *
+ * @cat: Category to look up
+ * @return category name (which may be a uclass driver name)
+ */
+const char *log_get_cat_name(enum log_category_t cat);
+
+/**
+ * log_get_cat_by_name() - Look up a category by name
+ *
+ * @name: Name to look up
+ * @return category ID, or LOGC_NONE if not found
+ */
+enum log_category_t log_get_cat_by_name(const char *name);
+
+/**
+ * log_get_level_name() - Get the name of a log level
+ *
+ * @level: Log level to look up
+ * @return log level name (in ALL CAPS)
+ */
+const char *log_get_level_name(enum log_level_t level);
+
+/**
+ * log_get_level_by_name() - Look up a log level by name
+ *
+ * @name: Name to look up
+ * @return log level ID, or LOGL_NONE if not found
+ */
+enum log_level_t log_get_level_by_name(const char *name);
+
+/* Log format flags (bit numbers) for gd->log_fmt. See log_fmt_chars */
+enum log_fmt {
+ LOGF_CAT = 0,
+ LOGF_LEVEL,
+ LOGF_FILE,
+ LOGF_LINE,
+ LOGF_FUNC,
+ LOGF_MSG,
+
+ LOGF_COUNT,
+ LOGF_DEFAULT = (1 << LOGF_FUNC) | (1 << LOGF_MSG),
+ LOGF_ALL = 0x3f,
+};
+
+/* 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