Move libmain bss into external ram?

[expresspotato]

So does anyone know how to move the bss segment of a component (in this case main) into external ram? I seem to need to use a linker fragment, but not sure what extra directives or steps are needed, because I'm unfamiliar with the linker fragment.

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Per-archive contributions to ELF file:
            Archive File DRAM .data & 0.bss .ext_ram.bss .rtc_noinit .rtc.text .noinit IRAM0 .text & 0.vectors ram_st_total Flash .text & .rodata & .rodata_noload & .appdesc flash_total
                 libbt.a       4774       0        51347           0         0       0        1658           0        57779      503966    139630                0          0      650028
               libmain.a       2805    5881            0           1         0    1024       18193           0        27904       95248     85160                0          0      202431

So I tried to mimic the linker fragment found in idf, for another component, but it didn't seem to work...

CMakeLists.txt (in the main folder)

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idf_component_register(
	SRCS 
                ...
		"main.c"
	INCLUDE_DIRS 
		"include"
		"ulp/include"
		"."
	LDFRAGMENTS "app.lf"
)

And a Linker Fragment of:

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[scheme:default]
entries:
    if ESP_ALLOW_BSS_SEG_EXTERNAL_MEMORY = y:
        bss -> extern_ram
    else:
        bss -> dram0_bss

[mapping:main]
archive: libmain.a
entries:
    * (bss);

But the results remain the same...

[MicroController]

https://docs.espressif.com/projects/esp ... config-bss

Additional data can be moved from the internal BSS segment to external RAM by applying the macro EXT_RAM_BSS_ATTR to any static declaration (which is not initialized to a non-zero value).

[expresspotato]

https://docs.espressif.com/projects/esp ... config-bss

Additional data can be moved from the internal BSS segment to external RAM by applying the macro EXT_RAM_BSS_ATTR to any static declaration (which is not initialized to a non-zero value).

Hey, thanks for your reply.

The page says "It is also possible to place the BSS section of a component or a library to external RAM using linker fragment scheme extram_bss."

Rather than go at it variable by variable, it seems like I could place the entire segment there with the correct linker fragment directive.

I don't know enough of how the linker works to come up with anything meaningful.