perusing the code related to the global data ptr and noticed in common/board_f.c:
/* * Pointer to initial global data area * * Here we initialize it if needed. */ #ifdef XTRN_DECLARE_GLOBAL_DATA_PTR #undef XTRN_DECLARE_GLOBAL_DATA_PTR #define XTRN_DECLARE_GLOBAL_DATA_PTR /* empty = allocate here */ DECLARE_GLOBAL_DATA_PTR = (gd_t *) (CONFIG_SYS_INIT_GD_ADDR); #else DECLARE_GLOBAL_DATA_PTR; #endif
i was curious to see if anything took advantage of that and the only other place in the code that referred to that was in arch/powerpc/include/asm/global_data.h:
#if 1 #define DECLARE_GLOBAL_DATA_PTR register volatile gd_t *gd asm ("r2") #else /* We could use plain global data, but the resulting code is bigger */ #define XTRN_DECLARE_GLOBAL_DATA_PTR extern #define DECLARE_GLOBAL_DATA_PTR XTRN_DECLARE_GLOBAL_DATA_PTR \ gd_t *gd #endif
and given the "#if 1", it's pretty clear powerpc doesn't care about that, and that file common/board_f.c is the only place i can see in the entire code base that refers to CONFIG_SYS_INIT_GD_ADDR.
so are people still taking advantage of this in some way?
rday