Problem :
The boot sequence of the Raspberry Pi is basically this:
Stage 1 boot is in the on-chip ROM. Loads Stage 2 in the L2 cache
Stage 2 is bootcode.bin. Enables SDRAM and loads Stage 3
Stage 3 is loader.bin. It knows about the .elf format and loads start.elf
start.elf loads kernel.img. It then also reads config.txt, cmdline.txt and bcm2835.dtb If the dtb file exists, it is loaded at 0×100 & kernel @ 0×8000 If disable_commandline_tags is set it loads kernel @ 0×0 Otherwise it loads kernel @ 0×8000 and put ATAGS at 0×100
kernel.img is then run on the ARM.
But BEFORE loading bootcode.bin i need to turn on Watchdog and calculate the time of boot till it loads login page.
when i login then it should show the time of boot load.
Solution :
How about forgetting all the things happening and just reading the output of dmesg, looking for a significant line happening just before the login prompt is shown (or possibly something specifically triggered/printed by you)?