wolfTPM Support For Das U-Boot Bootloader

[aidangarske]

Description

Experimental support for u-boot with wolfTPM.

• Recommended to use the SOFT SPI driver in U-boot
• wolfTPM serves as a TPM 2.0 driver thanks to its internal TIS layer
• wolfTPM provides native API with full access to all TPM 2.0 commands
• wolfTPM offers wrappers API for complex and common TPM 2.0 operations
• Two paths customers can take:
  __linux__ utilizes the existing tpm interface through tpm2_linux.c
__UBOOT__ directly talks to TPM with SPI through tpm_io_uboot.c

U-Boot TPM commands to be added:

• Get Capability (report device details including key group)
  Tested in QEMU with SWTPM
• Start Firmware Update (not tested)
  manifest_addr manifest_sz firmware_addr firmware_sz
• Cancel / Abandon (not tested)

Testing

Refer to readme - tested caps with qemu and swtpm simulator

Documentation

examples/u-boot/README.md