Unable to write to SecMon HPSVCR

[shivesh_sood]

Hi,

We have a setup with secure boot running (RCW[SB_EN] = 1) with our custom boot code on LS1046ARDB using Flow B outlined in LSDK Documentation. We would like to test authentication failure case where the board is put into a reset loop (SSM_STATE is soft fail) without blowing ITS Fuse.  

1.    We are unable to write to HPSVCR register in SecMon to set the auth failure as a fatal security violation. Any write operation using debug access results in no change of register value. How can we write to this register?
2.   We are also trying to provide an alternate boot image in case authentication of first boot image fails. As per LS1046ARM_Reference_Manual, DCFG ScratchRW3 should be written with the CSF header address for alternate boot image. When we test authentication fail for the first image, we get no error in DCFG ScratchRW4. However, the alternate boot image is not executed. Are we missing any additional steps in achieving this?

Thanks,

Shivesh Sood

rashmitharamesh.nair@collins.com‌

[yipingwang]

For Q1, to test security violation, you cannot write to HPSVCR, which sample the signal.
The proper way to test it is write to SecMon_HP Command Register (HPCOMR).
bit 9
SW_FSV
Software Fatal Security Violation

bit 8
SW_SV
Software Security Violation

Please refer to the documentation for how it will affect the SSM_STATE state.

For Q2, what version of LSDK customer is using? They have to follow the LSDK instruction to put the alternate image in the build script (Sample Input File). For LSDK1906, chapter 6.1.1.6 cover that.
If customer still have issues, please provide memory dump for entire SFP and SECMON, scratchRW1 to 4, and the images that they use. We can take a look.