[U-Boot-Users] How to Understanding Internal SRAM (of ARM)

[liang a lei]

hi, 

I am reading source of "~/lib-arm/board", and wander on the "gd_data", it's declared like:

void start_armboot (void)
{
	DECLARE_GLOBAL_DATA_PTR;
	:
	gd_t gd_data;
	:
	:
	/* Pointer is writable since we allocated a register for it */
	gd = &gd_data;
	memset ((void *)gd, 0, sizeof (gd_t));
	:
}

My question is: gd_data must or may be lacated at Internal SRAM (in arm, by disable cache, it is?), but how to force the linker to allocate "gd_data" to some specific place(which I mean to Internal SRAM) instead of external RAM? 
(BTW, I just begin to learn to read&understanding Makefile, and lib-arm/Makefile and topdir's config.mk has been read to find some FLAGS hints, but no answer. So bother you to give me a hint, thanks )