STM32H745 – DMA works on CM7 but not on CM4 core

[Rakesh212]

I am working on STM32H745BIT6 (dual-core: Cortex-M7 + Cortex-M4).

Issue:

• DMA is functioning correctly when used from the CM7 core
• The same DMA configuration does NOT work when executed from the CM4 core

[Gyessine]

Hello ​@Rakesh212 
You need to provide more details about your issue so help can be provided.
Can you share more details about your use case maybe your project or code .
You can read :How to write your question to maximize your chances to find a solution | Community
BR
Gyessine

[Saket_Om]

Hello ​@Rakesh212 

 

On STM32H745 dual-core devices, a common reason why a DMA transfer works on CM7 but not on CM4, even with the same peripheral and DMA settings, is the location of the DMA buffers in memory and, when applicable, cache management on CM7. The two cores do not have identical access to all memory regions, and some memories that are accessible from CM7 are not accessible from CM4 and/or from a given DMA controller. Therefore, in a dual-core application, it is important to place DMA source and destination buffers in a memory region that is accessible both by the CM4 core and by the DMA used, and to verify the linker script accordingly.