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SPati.7
Associate III
August 18, 2022
Question

What are Boot Steps of STM32H7 Secure Mode

  • August 18, 2022
  • 1 reply
  • 4192 views

As per my understanding Secure Mode of STM32H7 as follows:

RESET => Enter System Boot loader => Program OB register content => If (SECURITY) => RSS Boot => Configure Secure User Memory => Jump to Secure User memory on User Flash.

I have two open questions here

  1. is the above understanding correct ?? OB registers programmed by System Bootrom or some different mechanism ??
  2. Once Jump to application, Secure User Memory is disabled, as per concept. And if application trying to access Secure User memory from application context, the Flash access exception will come.

Who is checking this access ?? who will control this access ? how it is implemented ??

This topic has been closed for replies.

1 reply

Pavel A.
Super User
August 19, 2022
  1. Basically yes
  2. The "jump to application" must be done via call to a RSS function (thru a pointer), otherwise it will stay in the secure mode!

> Who is checking this access ?? how it is implemented ??

The hardware.

SPati.7
SPati.7Author
Associate III
August 19, 2022

Thanks for reply. But How it is implemented at HW level ??

Pavel A.
Super User
August 21, 2022

Hmm... They put a tiny gnome in every chip. These little guys do all the mаgi�?k.