trace: Update the file header

It seems better to put the TEXT_BASE value in the file header rather than
in an entry record. While it is true that there is a separate base for
pre-relocation, this can be handled by using offsets in the file.

It is useful to have a version number in case we need to change the trace
format again.

Update the header to make these changes.

Signed-off-by: Simon Glass <sjg@chromium.org>

2 files changed, 14 insertions, 17 deletions

diff --git a/include/trace.h b/include/trace.h
index e7aee02..2be8d81 100644
--- a/include/trace.h
+++ b/include/trace.h
@@ -6,6 +6,8 @@
 #ifndef __TRACE_H
 #define __TRACE_H
 
+/* this file is included from a tool so uses uint32_t instead of u32, etc. */
+
 enum {
 	/*
 	 * This affects the granularity of our trace. We can bin function
@@ -23,6 +25,8 @@ enum {
 	 * this value.
 	 */
 	FUNC_SITE_SIZE	= 4,	/* distance between function sites */
+
+	TRACE_VERSION	= 1,
 };
 
 enum trace_chunk_type {
@@ -39,7 +43,11 @@ struct trace_output_func {
 /* A header at the start of the trace output buffer */
 struct trace_output_hdr {
 	enum trace_chunk_type type;	/* Record type */
-	size_t rec_count;		/* Number of records */
+	uint32_t version;		/* Version (TRACE_VERSION) */
+	uint32_t rec_count;		/* Number of records */
+	uint32_t spare;			/* 0 */
+	uint64_t text_base;		/* Value of CONFIG_TEXT_BASE */
+	uint64_t spare2;		/* 0 */
 };
 
 /* Print statistics about traced function calls */
@@ -63,7 +71,7 @@ int trace_list_functions(void *buff, size_t buff_size, size_t *needed);
 enum ftrace_flags {
 	FUNCF_EXIT		= 0UL << 30,
 	FUNCF_ENTRY		= 1UL << 30,
-	FUNCF_TEXTBASE		= 2UL << 30,
+	/* two more values are available */
 
 	FUNCF_TIMESTAMP_MASK	= 0x3fffffff,
 };
diff --git a/lib/trace.c b/lib/trace.c
index b9dc6d2..2e2c1be 100644
--- a/lib/trace.c
+++ b/lib/trace.c
@@ -118,18 +118,6 @@ static void notrace add_ftrace(void *func_ptr, void *caller, ulong flags)
 	hdr->ftrace_count++;
 }
 
-static void notrace add_textbase(void)
-{
-	if (hdr->ftrace_count < hdr->ftrace_size) {
-		struct trace_call *rec = &hdr->ftrace[hdr->ftrace_count];
-
-		rec->func = CONFIG_TEXT_BASE;
-		rec->caller = 0;
-		rec->flags = FUNCF_TEXTBASE;
-	}
-	hdr->ftrace_count++;
-}
-
 /**
  * __cyg_profile_func_enter() - record function entry
  *
@@ -278,8 +266,11 @@ int trace_list_calls(void *buff, size_t buff_size, size_t *needed)
 
 	/* Update the header */
 	if (output_hdr) {
+		memset(output_hdr, '\0', sizeof(*output_hdr));
 		output_hdr->rec_count = upto;
 		output_hdr->type = TRACE_CHUNK_CALLS;
+		output_hdr->version = TRACE_VERSION;
+		output_hdr->text_base = CONFIG_TEXT_BASE;
 	}
 
 	/* Work out how must of the buffer we used */
@@ -385,10 +376,9 @@ int notrace trace_init(void *buff, size_t buff_size)
 	/* Use any remaining space for the timed function trace */
 	hdr->ftrace = (struct trace_call *)(buff + needed);
 	hdr->ftrace_size = (buff_size - needed) / sizeof(*hdr->ftrace);
-	add_textbase();
+	hdr->depth_limit = CONFIG_TRACE_CALL_DEPTH_LIMIT;
 
 	puts("trace: enabled\n");
-	hdr->depth_limit = CONFIG_TRACE_CALL_DEPTH_LIMIT;
 	trace_enabled = 1;
 	trace_inited = 1;
 
@@ -426,7 +416,6 @@ int notrace trace_early_init(void)
 	/* Use any remaining space for the timed function trace */
 	hdr->ftrace = (struct trace_call *)((char *)hdr + needed);
 	hdr->ftrace_size = (buff_size - needed) / sizeof(*hdr->ftrace);
-	add_textbase();
 	hdr->depth_limit = CONFIG_TRACE_EARLY_CALL_DEPTH_LIMIT;
 	printf("trace: early enable at %08x\n", CONFIG_TRACE_EARLY_ADDR);