This is only a patch to test if BSS was accessed in any function in init function array!
DO NOT APPLY TO MAINLINE!
To run the test adopt the bss_mirror value to point somwhere in RAM with sufficient space!
A step by step guide is like this: * apply the patch * adopt bss_mirror in arch/arm/lib/board.c:board_init_f() * build and run like always * search for something like: 'BSS got corrupted after init_fnc @ 0x20100478' after banner * use objdump to search the symbol ---8<--- arm-unknown-linux-gnueabi-objdump -S ../build_uboot-at91rm9200ek/u-boot | grep 20100478 20100478 <timer_init>: 20100478: e59f3064 ldr r3, [pc, #100] ; 201004e4 <timer_init+0x6c> --->8---
Signed-off-by: Andreas Bießmann andreas.devel@googlemail.com --- arch/arm/lib/board.c | 18 ++++++++++++++++++ 1 files changed, 18 insertions(+), 0 deletions(-)
diff --git a/arch/arm/lib/board.c b/arch/arm/lib/board.c index 1fd5f83..890e6f1 100644 --- a/arch/arm/lib/board.c +++ b/arch/arm/lib/board.c @@ -274,6 +274,10 @@ void board_init_f (ulong bootflag) init_fnc_t **init_fnc_ptr; gd_t *id; ulong addr, addr_sp; + uint32_t *bss_mirror; + uint32_t *bss_start; + size_t bss_length; + init_fnc_t *break_bss = NULL;
/* Pointer is writable since we allocated a register for it */ gd = (gd_t *) (CONFIG_SYS_INIT_SP_ADDR); @@ -284,12 +288,26 @@ void board_init_f (ulong bootflag)
gd->mon_len = _bss_end_ofs;
+ /* take a location in SDRAM which might be free */ + bss_mirror = (uint32_t*)(CONFIG_SYS_SDRAM_BASE + 0x600000); + bss_start = (uint32_t*)(_bss_start_ofs + _TEXT_BASE); + bss_length = _bss_end_ofs - _bss_start_ofs; + memcpy((void*)bss_mirror, (void*)bss_start, bss_length); + for (init_fnc_ptr = init_sequence; *init_fnc_ptr; ++init_fnc_ptr) { if ((*init_fnc_ptr)() != 0) { hang (); } + if (!break_bss) + if (memcmp((void*)bss_mirror, bss_start, bss_length) != 0) + break_bss = *init_fnc_ptr; }
+ if (break_bss) + printf("BSS got corrupted after init_fnc @ 0x%p\n", *break_bss); + else + printf("BSS is still OK after init_fnc\n"); + debug ("monitor len: %08lX\n", gd->mon_len); /* * Ram is setup, size stored in gd !!