bootstage: Allow marking a particular line of code

Add a function which allows a (file, function, line number) to be marked
in bootstage.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Che-Liang Chiou <clchiou@chromium.org>
diff --git a/common/bootstage.c b/common/bootstage.c
index 15afa24..c5c6996 100644
--- a/common/bootstage.c
+++ b/common/bootstage.c
@@ -30,6 +30,8 @@
 
 #include <common.h>
 #include <libfdt.h>
+#include <malloc.h>
+#include <linux/compiler.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -117,6 +119,33 @@
 	return bootstage_add_record(id, name, flags, timer_get_boot_us());
 }
 
+ulong bootstage_mark_code(const char *file, const char *func, int linenum)
+{
+	char *str, *p;
+	__maybe_unused char *end;
+	int len = 0;
+
+	/* First work out the length we need to allocate */
+	if (linenum != -1)
+		len = 11;
+	if (func)
+		len += strlen(func);
+	if (file)
+		len += strlen(file);
+
+	str = malloc(len + 1);
+	p = str;
+	end = p + len;
+	if (file)
+		p += snprintf(p, end - p, "%s,", file);
+	if (linenum != -1)
+		p += snprintf(p, end - p, "%d", linenum);
+	if (func)
+		p += snprintf(p, end - p, ": %s", func);
+
+	return bootstage_mark_name(BOOTSTAGE_ID_ALLOC, str);
+}
+
 uint32_t bootstage_start(enum bootstage_id id, const char *name)
 {
 	struct bootstage_record *rec = &record[id];
diff --git a/include/bootstage.h b/include/bootstage.h
index c8235e8..0f44e71 100644
--- a/include/bootstage.h
+++ b/include/bootstage.h
@@ -267,6 +267,19 @@
 ulong bootstage_mark_name(enum bootstage_id id, const char *name);
 
 /**
+ * Mark a time stamp in the given function and line number
+ *
+ * See BOOTSTAGE_MARKER() for a convenient macro.
+ *
+ * @param file		Filename to record (NULL if none)
+ * @param func		Function name to record
+ * @param linenum	Line number to record
+ * @return recorded time stamp
+ */
+ulong bootstage_mark_code(const char *file, const char *func,
+			  int linenum);
+
+/**
  * Mark the start of a bootstage activity. The end will be marked later with
  * bootstage_accum() and at that point we accumulate the time taken. Calling
  * this function turns the given id into a accumulator rather than and
@@ -358,6 +371,12 @@
 	return 0;
 }
 
+static inline ulong bootstage_mark_code(const char *file, const char *func,
+					int linenum)
+{
+	return 0;
+}
+
 static inline uint32_t bootstage_start(enum bootstage_id id, const char *name)
 {
 	return 0;
@@ -379,4 +398,8 @@
 }
 #endif /* CONFIG_BOOTSTAGE */
 
+/* Helper macro for adding a bootstage to a line of code */
+#define BOOTSTAGE_MARKER()	\
+		bootstage_mark_code(__FILE__, __func__, __LINE__)
+
 #endif