bootstage: Implement core 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.

Most IDs are not named at this stage. For that I would first like to
renumber them all.

Timer summary in microseconds:
       Mark    Elapsed  Stage
          0          0  reset
    205,000    205,000  board_init_f
  6,053,000  5,848,000  bootm_start
  6,053,000          0  id=1
  6,058,000      5,000  id=101
  6,058,000          0  id=100
  6,061,000      3,000  id=103
  6,064,000      3,000  id=104
  6,093,000     29,000  id=107
  6,093,000          0  id=106
  6,093,000          0  id=105
  6,093,000          0  id=108
  7,089,000    996,000  id=7
  7,089,000          0  id=15
  7,089,000          0  id=8
  7,097,000      8,000  start_kernel

Signed-off-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Simon Glass
2012-02-13 13:51:19 +00:00
committed by Wolfgang Denk
parent 770605e4f9
commit 3a608ca01d
4 changed files with 227 additions and 0 deletions

25
README
View File

@@ -2261,6 +2261,31 @@ The following options need to be configured:
example, some LED's) on your board. At the moment,
the following checkpoints are implemented:
- Detailed boot stage timing
CONFIG_BOOTSTAGE
Define this option to get detailed timing of each stage
of the boot process.
CONFIG_BOOTSTAGE_USER_COUNT
This is the number of available user bootstage records.
Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
a new ID will be allocated from this stash. If you exceed
the limit, recording will stop.
CONFIG_BOOTSTAGE_REPORT
Define this to print a report before boot, similar to this:
Timer summary in microseconds:
Mark Elapsed Stage
0 0 reset
3,575,678 3,575,678 board_init_f start
3,575,695 17 arch_cpu_init A9
3,575,777 82 arch_cpu_init done
3,659,598 83,821 board_init_r start
3,910,375 250,777 main_loop
29,916,167 26,005,792 bootm_start
30,361,327 445,160 start_kernel
Legacy uImage format:
Arg Where When