Add trace support to generic board

Add hooks for tracing to generic board, including:

- allow early tracing to start early as possible in U-Boot
- reserve memory for trace buffer
- copy early trace buffer to main trace buffer after relocation
- setup full tracing support after relocation

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

common/board_r.c

@@ -58,6 +58,7 @@
 #include <serial.h>
 #include <spi.h>
 #include <stdio_dev.h>
+#include <trace.h>
 #include <watchdog.h>
 #ifdef CONFIG_ADDR_MAP
 #include <asm/mmu.h>
@@ -106,6 +107,15 @@ static int initr_secondary_cpu(void)
 	return 0;
 }
 
+static int initr_trace(void)
+{
+#ifdef CONFIG_TRACE
+	trace_init(gd->trace_buff, CONFIG_TRACE_BUFFER_SIZE);
+#endif
+
+	return 0;
+}
+
 static int initr_reloc(void)
 {
 	gd->flags |= GD_FLG_RELOC;	/* tell others: relocation done */
@@ -711,6 +721,7 @@ static int run_main_loop(void)
  * TODO: perhaps reset the watchdog in the initcall function after each call?
  */
 init_fnc_t init_sequence_r[] = {
+	initr_trace,
 	initr_reloc,
 	/* TODO: could x86/PPC have this also perhaps? */
 #ifdef CONFIG_ARM