SPRADU1 September   2026 AM62A3 , AM62A7

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Boot Process
    1. 2.1 SPL Boot Process
      1. 2.1.1 R5 SPL
      2. 2.1.2 TF-A+OPTEE+A53 SPL
      3. 2.1.3 U-Boot
      4. 2.1.4 Linux and User Mode
    2. 2.2 SPL Falcon Mode
      1. 2.2.1 Steps
        1. 2.2.1.1 Installing Linux SDK
        2. 2.2.1.2 Adding Falcon Script
        3. 2.2.1.3 Compiling Linux Device Tree
        4. 2.2.1.4 Creating tispl.bin
        5. 2.2.1.5 Creating a Bootable Card
    3. 2.3 Replacing SPL With SBL
      1. 2.3.1 Falcon Boot in SBL
  6. 3Boot Media
  7. 4Operating System Boot Optimization
    1. 4.1 Trimming Operating System
      1. 4.1.1 Using Preset Trimming Configuration
      2. 4.1.2 Custom Trimming
    2. 4.2 Reducing Log Output
  8. 5Userspace Optimization
    1. 5.1 Customizing Boot Services Using Systemd
  9. 6Minimizing Boot Services Using init Script
  10. 7Conclusion
  11. 8References

2.1.2 TF-A+OPTEE+A53 SPL

As the name shows, the TF-A+OPTEE+A53 SPL (hereinafter referred to as A53 SPL) process consists of loading and running the ARM Trusted Firmware (ATF), OP-TEE, and A53 SPL. These images are all packaged in tispl.bin, and configuration descriptions such as the image loading locations in the package are stored in the Device Tree binary k3-binman.dtsi. The structure of tispl.bin is shown in the following figure, including ATF, OP-TEE, DM image, SPL image, and some Device Tree binaries.

tispl Image PackageFigure 2-5 tispl Image Package

The corresponding packaging log is shown below. The U-Boot.img is packaged together.

Pack completed after 1 pass(es)
Writing image to './custMpk.pem'
Wrote 0xcab bytes
Pack completed after 1 pass(es)
Writing image to './ti-degenerate-key.pem'
Wrote 0x21a bytes
Pack completed after 1 pass(es)
Writing image to './ti-dm.bin'
Wrote 0x8edf0 bytes
Pack completed after 1 pass(es)
Writing image to './tifsstub.bin_hs'
Wrote 0x6d1 bytes
Pack completed after 1 pass(es)
Writing image to './tifsstub.bin_fs'
Wrote 0x0 bytes
Pack completed after 1 pass(es)
Writing image to './tifsstub.bin_gp'
Wrote 0x3ca bytes
Pack completed after 1 pass(es)
Writing image to './tispl.bin'
Wrote 0x165bab bytes
Pack completed after 1 pass(es)
Writing image to './u-boot.img'
Wrote 0x11ff63 bytes
Pack completed after 1 pass(es)
Writing image to './tispl.bin_unsigned'
Wrote 0x163a77 bytes
Pack completed after 1 pass(es)
Writing image to './u-boot.img_unsigned'
Wrote 0x11f21b bytes

The boot log for A53 SPL is as follows. This stage takes approximately 1.4s. The majority of the time is spent on moving and loading the corresponding image files, which is closely related to the boot media.

 [2025-08-05 19:53:27.425] 
[2025-08-05 19:53:27.425] NOTICE: BL31: v2.11.0(release):v2.11.0-906-g58b25570c9-dirty
[2025-08-05 19:53:27.425] NOTICE: BL31: Built : 04:20:32, Nov 1 2024
[2025-08-05 19:53:27.681]
[2025-08-05 19:53:27.681] U-Boot SPL 2024.04-ti-g29d0c23d67ee (Nov 29 2024 - 11:41:54 +0000)
[2025-08-05 19:53:27.681] SYSFW ABI: 4.0 (firmware rev 0x000a '10.1.8--v10.01.08 (Fiery Fox)')
[2025-08-05 19:53:27.696] Trying to boot from MMC2
 [2025-08-05 19:53:28.193] Authentication passed 

 [2025-08-05 19:53:28.833] Authentication passed

At this stage, two images also undergo authentication, indicated by the "Authentication passed" message in the boot log, corresponding to the code ti_secure_image_post_process(). The authentication only applies to the DM image and the Device Tree binaries, while ATF and OP-TEE are not authenticated. This process consumes less time and has little impact on the overall boot speed.