TMS320F28374D: CLA code with overlay

Fabrice Mousset

Part Number: TMS320F28374D

Tool/software:

Hi all,

I have a software which has multiple work modes.

The code uses either CPU and CLA. As the CLA part is splitted in many functions which I use according the current working mode.

But memory available for CLA is constrained (only LS space), I would like to know if it is possible to define an overlay?

As I only use a couple of CLA function in each configuration, the idea is to load the corresponding functions for the actual working mode.

My CLA function are named as follow:y

CLA1ModeA_xxxx : all CLA functions used for mode A
CLA1ModeB_xxxx : all CLA functions used for mode B
etc.

My CLA sections are defined as follow in the linker file:

   Cla1Prog         : LOAD = FLASHG,
                      RUN = RAMLS1_5,
                      LOAD_START(_Cla1funcsLoadStart),
                      LOAD_END(_Cla1funcsLoadEnd),
                      RUN_START(_Cla1funcsRunStart),
                      LOAD_SIZE(_Cla1funcsLoadSize),
                      PAGE = 0, ALIGN(4)
                      
   CLAscratch       :
                     { *.obj(CLAscratch)
                     . += CLA_SCRATCHPAD_SIZE;
                     *.obj(CLAscratch_end) } >  RAMLS0,  PAGE = 1

   .scratchpad      : > RAMLS0, PAGE = 1
   .bss_cla         : > RAMLS0, PAGE = 1
   .const_cla	    : LOAD = FLASHG,
                      RUN = RAMLS0,
                      RUN_START(_Cla1ConstRunStart),
                      LOAD_START(_Cla1ConstLoadStart),
                      LOAD_SIZE(_Cla1ConstLoadSize),
                      PAGE = 1

How do I have to change this to use overlay with UNION and GROUP?

UNION
{
    GROUP
    {
       ???
    } load = FLASHG, LOAD_START(_taskA_load_start), SIZE(_taskA_size)
    GROUP
    {
       ???
    } load = FLASHG, LOAD_START(_taskB_load_start), SIZE(_taskB_size)
} run = RAMLS1_5, RUN_START(_task_run_start)

Thanks for any help.

Best regards

Fabrice

3 months ago

0 Delaney Woodward 3 months ago

TI__Expert 7240 points

Hi Fabrice,

I would suggest keeping the CLA memory allocations the same in the linker cmd file and adding #if statements around each function to check which working mode is chosen. You can add a #define to refer to which working mode is being run and #if statements could check for this.

For example, you could have:

#define WORKING_MODE 1

#if WORKING_MODE == 1

//include function definitions for CLA1ModeA_xxxx functions

#endif

#if WORKING_MODE == 2

//include function definitions for CLA1ModeB_xxxx functions

#endif

You could also alternatively include predefined symbols for each working mode and wrap the functions in #ifdef statements.

This way, the compiler won't actually allocate CLA memory for functions that aren't needed in the current working mode. Let me know if this would be a viable solution for you.

Best Regards,

Delaney

0 Fabrice Mousset 3 months ago in reply to Delaney Woodward

Prodigy 40 points

Hi Delaney,

Thanks for your input, but this is not really what I want to do.

Using defines means having multiple compiled version. The CLA routines are "static" and I can not change the configuration "on the fly".

Want I want to do, is to have all the CLA routines compiled and stored in FLASH but only load the functions group I need in RAM according to boot configuration.

Best regards,

Fabrice

0 Fabrice Mousset 3 months ago

Prodigy 40 points

I found myself a solution which seems to work.

It is quiet simple: use #pragma CODE_SECTION to move wanted functions into a specific code section!

For example:

#pragma CODE_SECTION(Cla1ModeATask1, "Cla1ModeA");
__interrupt void Cla1ModeATask1() {... }

#pragma CODE_SECTION(Cla1ModeATask2, "Cla1ModeA");
__interrupt void Cla1ModeATask2() {... }

...

#pragma CODE_SECTION(Cla1ModeBTask1, "Cla1ModeB");
__interrupt void Cla1ModeBTask1() {... }

#pragma CODE_SECTION(Cla1ModeBTask2, "Cla1ModeB");
__interrupt void Cla1ModeBTask2() {... }

And then in the linker file

// mode specific functions
UNION
{
    GROUP
    {
        Cla1ModeA : {}
    } LOAD = FLASHG, LOAD_START(_Cla1ModeALoadStart), SIZE(_Cla1ModeALoadSize)

    GROUP
    {
        Cla1ModeB : {}
    } LOAD = FLASHG, LOAD_START(_Cla1ModeBLoadStart), SIZE(_Cla1ModeBLoadSize)

} RUN = RAMLS1_5, RUN_START(_Cla1OptionsRunStart), PAGE = 0

//Cla1Prog contains the common code
Cla1Prog    : LOAD = FLASHG,
              RUN = RAMLS1_5,
              LOAD_START(_Cla1funcsLoadStart),
              LOAD_END(_Cla1funcsLoadEnd),
              RUN_START(_Cla1funcsRunStart),
              LOAD_SIZE(_Cla1funcsLoadSize),
              PAGE = 0, ALIGN(4)

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TMS320F28374D: CLA code with overlay