Address swapping of SDRAM

Hi ST Community,

I am working on STM32H563 with external SDRAM connected through FMC.

I am trying to use:

• heap in SDRAM
• global variables in SDRAM
• execution/data access from SDRAM
• DCACHE enabled

Current SDRAM mapping:

0xC0000000

I noticed that in STM32F7/H7 examples there is support for:

HAL_REMAPMEMORY_FMC_SDRAM()

which remaps FMC SDRAM memory regions internally.

I found this in STM32F7 HAL:

__HAL_SYSCFG_REMAPMEMORY_FMC_SDRAM()

But on STM32H563 I cannot find any equivalent remap mechanism or SYSCFG macro.

My questions are:

1. Is there any equivalent SDRAM remap functionality available on STM32H563 / STM32H5?
2. Is SDRAM fixed permanently at 0xC0000000 on STM32H5 architecture?
3. Does STM32H5 treat SDRAM at 0xC0000000 differently regarding:

• DCACHE
• burst accesses
• MPU memory attributes
• speculative accesses

1. Are there any special MPU/DCACHE recommendations for using:

• malloc()/calloc() heap in SDRAM
• .bss/.data sections in SDRAM
• execution from SDRAM

Current observations:

• SDRAM works correctly when DCACHE is disabled
• malloc(), memset(), counters, global variables all work properly without DCACHE
• When DCACHE is enabled, SDRAM accesses become unstable/fail
• Tried both cacheable and non-cacheable MPU attributes
• SDRAM configured as Normal Memory
• FMC SDRAM initialization sequence follows standard HAL sequence

I want to understand whether there is any architectural difference between STM32F7/H7 and STM32H5 regarding FMC SDRAM mapping and DCACHE interaction.

Any guidance or reference examples for STM32H563 SDRAM + DCACHE would be very helpful.

Thank you.