Request for Linker Script to Place Code/Data in TCM (Cortex-M7, i.MX8MP)

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Hello Prem0919,

Thank you for your question! I understand you want to ensure that all code and data for the Cortex-M7 are placed in ITCM and DTCM on the Verdin iMX8M Plus for the best performance.

Below is a template for a GNU ld (linker script) file that will place your code (.text), read-only data (.rodata), initialized data (.data), and zero-initialized data (.bss) into the appropriate TCM regions:

/* Verdin iMX8M Plus M7 TCM linker script example */

/* ITCM: 128KB at 0x00000000 - 0x0001FFFF (for code) */
/* DTCM: 128KB at 0x20000000 - 0x2001FFFF (for data) */

MEMORY
{
  ITCM (rx) : ORIGIN = 0x00000000, LENGTH = 128K
  DTCM (rwx) : ORIGIN = 0x20000000, LENGTH = 128K
}

SECTIONS
{
  /* Place code and read-only data in ITCM */
  .text :
  {
    KEEP(*(.isr_vector))
    *(.text*)
    *(.rodata*)
    *(.glue_7)
    *(.glue_7t)
    *(.eh_frame*)
  } > ITCM

  /* Initialized data in DTCM */
  .data : AT(__data_load_addr)
  {
    __data_start__ = .;
    *(.data*)
    . = ALIGN(4);
    __data_end__ = .;
  } > DTCM
  __data_load_addr = LOADADDR(.data);

  /* Uninitialized data (BSS) in DTCM */
  .bss (NOLOAD) :
  {
    __bss_start__ = .;
    *(.bss*)
    *(COMMON)
    . = ALIGN(4);
    __bss_end__ = .;
  } > DTCM

  /* Stack can also be allocated in DTCM if required */
  __StackTop = ORIGIN(DTCM) + LENGTH(DTCM);
  __StackLimit = __StackTop - 0x400; /* Example: 1KB stack */

  /* ... other sections as necessary ... */
}

/* Provide symbols for startup code */
PROVIDE(__stack = __StackTop);

Notes:

  • Modify sizes if your application is getting close to the 128KB limits.
  • Make sure your startup (crt0) code copies the .data section from flash/ROM/load address to DTCM at startup.
  • The actual section labels (.text, .data, .bss) should match what is used by your toolchain/startup code.

For more details regarding addresses, refer to the memory regions described here:

It is also advisable to review MCUXpresso SDK examples for the i.MX8MP, as they include linker scripts tailored for this platform:

Let me know if you need further clarification or help customizing the script for your project!

Best regards, Toradex AI Assistant.