1 Article purpose[edit source]
The purpose of this article is to:
- briefly introduce the DBGMCU peripheral and its main features
- indicate the level of security supported by this hardware block
- explain how each instance can be allocated to the three runtime contexts and linked to the corresponding software components
- explain, when necessary, how to configure the DBGMCU peripheral.
2 Peripheral overview[edit source]
The DBGMCU peripheral is used to configure internal peripherals behavior when one of the cores (Cortex®-A7 or Cortex®-M4) enters in debug mode.
For instance, it allows to freeze a watchdog (IWDG) to avoid getting a watchdog reset when the Cortex®-A7 enters in debug mode (via a breakpoint or JTAG break).
2.1 Features[edit source]
Refer to the STM32MP15 reference manuals for the complete list of features, and to the software components, introduced below, to see which features are implemented.
2.2 Security support[edit source]
The DBGMCU is a non secure peripheral.
3 Peripheral usage and associated software[edit source]
3.1 Boot time[edit source]
DBGMCU is partly initialized by the FSBL at boot time in order to freeze IWDG2 when the Cortex®-A7 enters in debug mode.
3.2 Runtime[edit source]
3.2.1 Overview[edit source]
There is no real runtime support for DBGMCU. Instead, users who need to freeze some peripherals for a debug session should complete the minimal initialization done in the FSBL with their needs.
3.2.2 Software frameworks[edit source]
Internal peripherals software table template
| Trace & Debug | DBGMCU | | | | |- |}
3.2.3 Peripheral configuration[edit source]
The configuration is applied by the firmware running in the context to which the peripheral is assigned. The configuration can be done alone via the STM32CubeMX tool for all internal peripherals, and then manually completed (particularly for external peripherals), according to the information given in the corresponding software framework article.
3.2.4 Peripheral assignment[edit source]
Internal peripherals assignment table template
| rowspan="1" | Trace & Debug | rowspan="1" | DBGMCU | DBGMCU | | | | No assignment |-
|}