Hi tiger...@viatech.com.cn, On Wed, 3 Jul 2013 11:19:13 +0800, <tiger...@viatech.com.cn> wrote:
> Hi, experts: > I am studying u-boot latest code now. > I have a question about monitor length. > 1. in board_init_f() function in arch\arm\lib\board.c > Gd->mon_len = _bss_end_ofs; > 2. in board_init_r() function in arch\arm\lib\board.c > Monitor_flash_len = _end_ofs; > > Because _end_ofs < _bss_end_ofs, so it confused me! > Why need to discard some data when re-calculating monitor_in board_init_r() > function. Both functions don't compute the same thing. GD->mon_len computes the monitor length including BSS, because it is the length in RAM at run time, which matters e.g. for relocating the monitor -- relocation copies the text and data but not the BSS. Monitor_flash_len, as the name implies, computes the monitor length excluding BSS, because this is the length in FLASH, and BSS does not exist in the flashed image; even if we know its size at build time, BSS will only exist after relocation, just before entering board_init_r. > Best wishes, Amicalement, -- Albert. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
