Hi,
in STM32H7, in order to user the DMA for USARTS, the DMA is controlling the D1/D2 memory regions.
therefor I need to locate the DMA rx buffers in these regions (2400000).
(https://community.st.com/s/article/FAQ-DMA-is-not-working-on-STM32H7-devices)
I am not forcing anything to be written during flash.
there is no problem with flashing the hex file as is via SWD. just the bootloader has problems "flashing" ROM...
my linker script section is:
MEMORY
{
DTCMRAM (xrw) : ORIGIN = 0x20000000, LENGTH = 128K
RAM_D1 (xrw) : ORIGIN = 0x24005000, LENGTH = 492K
RAM_D2 (xrw) : ORIGIN = 0x30000000, LENGTH = 288K
RAM_D3 (xrw) : ORIGIN = 0x38000000, LENGTH = 64K
ITCMRAM (xrw) : ORIGIN = 0x00000000, LENGTH = 64K
FLASH (rx) : ORIGIN = 0x8000000, LENGTH = 2048K
}
/* User_heap_stack section, used to check that there is enough RAM left */
._user_heap_stack :
{
. = ALIGN(8);
PROVIDE ( end = . );
PROVIDE ( _end = . );
. = . + _Min_Heap_Size;
. = . + _Min_Stack_Size;
. = ALIGN(8);
} >DTCMRAM
.d1_block :
{
. = ALIGN(4);
*(.d1_block) /* .data sections */
} >RAM_D1
.d2_block :
{
. = ALIGN(4);
_sd2_block = .; /* create a global symbol at data start */
. = ALIGN(4);
*(.d2_block) /* .data sections */
_ed2_block = .; /* define a global symbol at data end */
} >RAM_D3
/* Ethernet Modification start */
.lwip_sec (NOLOAD) :
{
. = ABSOLUTE(0x30040000);
*(.RxDecripSection)
. = ABSOLUTE(0x30040060);
*(.TxDecripSection)
. = ABSOLUTE(0x30040200);
*(.RxArraySection)
} >RAM_D2
/* Ethernet Modification end */
and the code is located at D1:
uint8_t __attribute__ ((section (".d1_block"), aligned (4))) protocol_rx_buffer[128];
