Add microsecond boot time measurement

This defines the basics of a new boot time measurement feature. This allows
logging of very accurate time measurements as the boot proceeds, by using
an available microsecond counter.

To enable the feature, define CONFIG_BOOTSTAGE in your board config file.
Also available is CONFIG_BOOTSTAGE_REPORT which will cause a report to be
printed just before handing off to the OS.

BUG=chromium-os:13875
TEST=build and boot, check that progress is reported before running Linux:

Timer summary in microseconds:
       Mark    Elapsed  Stage
          0          0  awake
  2,181,078  2,181,078  usb_start
 11,861,817  9,680,739  bootp_start
 11,884,610     22,793  bootp_stop
 11,884,689         79  tftp start
 15,271,536  3,386,847  tftp done
 15,271,568         32  bootm_start
 15,406,551    134,983  start_kernel

Change-Id: I71b89c8402dc5dec75e68333bd24a6bab7500a1b
Reviewed-on: http://gerrit.chromium.org/gerrit/197
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>

1 files changed, 70 insertions, 0 deletions

diff --git a/include/bootstage.h b/include/bootstage.h
new file mode 100644
index 0000000000..ade5a13999
--- /dev/null
+++ b/include/bootstage.h
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2011, Google Inc. All rights reserved.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef __BOOTSTAGE_H
+#define __BOOTSTAGE_H
+
+/*
+ * These are the things that can be timestamped. There are some pre-defined
+ * by U-Boot, and some which are user defined.
+ */
+enum bootstage_id {
+	BOOTSTAGE_AWAKE,
+	BOOTSTAGE_START_UBOOT,
+	BOOTSTAGE_USB_START,
+	BOOTSTAGE_ETH_START,
+	BOOTSTAGE_BOOTP_START,
+	BOOTSTAGE_BOOTP_STOP,
+	BOOTSTAGE_KERNELREAD_START,
+	BOOTSTAGE_KERNELREAD_STOP,
+	BOOTSTAGE_BOOTM_START,
+	BOOTSTAGE_BOOTM_HANDOFF,
+
+	/* a few spare for the user, from here */
+	BOOTSTAGE_USER,
+
+	/*
+	 * Total number of entries - increase this at the cost of some BSS
+	 * and ATAG space.
+	 */
+	BOOTSTAGE_COUNT = 10
+};
+
+#ifdef CONFIG_BOOTSTAGE
+
+/*
+ * Mark a time stamp for the current boot stage.
+ */
+uint32_t bootstage_mark(enum bootstage_id id, const char *name);
+
+/* Print a report about boot time */
+void bootstage_report(void);
+
+#else
+
+static inline bootstage_mark(enum bootstage_id id, const char *name)
+{}
+
+#endif
+
+#endif
+