PREBOOT delay. Is it possible to reduce it?

Hi, I’m try to optimize boot time BeagleBone Black board. The forum already has a few helpful tips to reduce boot time in stage u-boot and linux kernel loading. But one question remains uncovered.

I found that there is a delay (near 2 sec) between the power on and the emergance of first debug message on serial port. I wonder what’s going on in those two seconds. Is it CPU initialization procedure, or the way to avoid jitter when plug in power supply. Is it possible to reduce this delay?

~[00:000] - plug in power supply
[02:291] ▒ <------- Look here [02:310] U-Boot SPL 2015.10-dirty (Nov 14 2015 - 13:18:58) [02:490] MMC: block number 0x100 exceeds max(0x0) [02:494] MMC: block number 0x200 exceeds max(0x0) [02:498] *** Error - No Valid Environment Area found [02:503] *** Warning - bad CRC, using default environment [02:519] [02:551] [02:551] U-Boot 2015.10-dirty (Nov 14 2015 - 13:18:58 -0800) [02:555] [02:555] Watchdog enabled [02:559] I2C: ready [02:613] DRAM: 512 MiB [02:661] Reset Source: Power-on reset has occurred. [02:665] MMC: OMAP SD/MMC: 0, OMAP SD/MMC: 1 [03:112] *** Warning - bad CRC, using default environment [03:132] [03:207] Net: not set. Validating first E-fuse MAC [03:249] cpsw [03:250] Hit any key to stop autoboot: 0 (autoboot.c) [03:255] gpio: pin 53 (gpio 53) value is 1 [03:330] switch to partitions #0, OK [03:332] mmc0 is current device

Regards.

  • Andrey Kuznetcov