1. 24 Feb, 2015 1 commit
    • Masahiro Yamada's avatar
      kconfig: switch to single .config configuration · e02ee254
      Masahiro Yamada authored
      When Kconfig for U-boot was examined, one of the biggest issues was
      how to support multiple images (Normal, SPL, TPL).  There were
      actually two options, "single .config" and "multiple .config".
      After some discussions and thought experiments, I chose the latter,
      i.e. to create ".config", "spl/.config", "tpl/.config" for Normal,
      SPL, TPL, respectively.
      
      It is true that the "multiple .config" strategy provided us the
      maximum flexibility and helped to avoid duplicating CONFIGs among
      Normal, SPL, TPL, but I have noticed some fatal problems:
      
      [1] It is impossible to share CONFIG options across the images.
        If you change the configuration of Main image, you often have to
        adjust some SPL configurations correspondingly.  Currently, we
        cannot handle the dependencies between them.  It means one of the
        biggest advantages of Kconfig is lost.
      
      [2] It is too painful to change both ".config" and "spl/.config".
        Sunxi guys started to work around this problem by creating a new
        configuration target.  Commit cbdd9a97 (sunxi: kconfig: Add
        %_felconfig rule to enable FEL build of sunxi platforms.) added
        "make *_felconfig" to enable CONFIG_SPL_FEL on both images.
        Changing the configuration of multiple images in one command is a
        generic demand.  The current implementation cannot propose any
        good solution about this.
      
      [3] Kconfig files are getting ugly and difficult to understand.
        Commit b724bd7d (dm: Kconfig: Move CONFIG_SYS_MALLOC_F_LEN to
        Kconfig) has sprinkled "if !SPL_BUILD" over the Kconfig files.
      
      [4] The build system got more complicated than it should be.
        To adjust Linux-originated Kconfig to U-Boot, the helper script
        "scripts/multiconfig.sh" was introduced.  Writing a complicated
        text processor is a shell script sometimes caused problems.
      
      Now I believe the "single .config" will serve us better.  With it,
      all the problems above would go away.  Instead, we will have to add
      some CONFIG_SPL_* (and CONFIG_TPL_*) options such as CONFIG_SPL_DM,
      but we will not have much.  Anyway, this is what we do now in
      scripts/Makefile.spl.
      
      I admit my mistake with my apology and this commit switches to the
      single .config configuration.
      
      It is not so difficult to do that:
      
       - Remove unnecessary processings from scripts/multiconfig.sh
        This file will remain for a while to support the current defconfig
        format.  It will be removed after more cleanups are done.
      
       - Adjust some makefiles and Kconfigs
      
       - Add some entries to include/config_uncmd_spl.h and the new file
         scripts/Makefile.uncmd_spl.  Some CONFIG options that are not
         supported on SPL must be disabled because one .config is shared
         between SPL and U-Boot proper going forward.  I know this is not
         a beautiful solution and I think we can do better, but let's see
         how much we will have to describe them.
      
       - update doc/README.kconfig
      
      More cleaning up patches will follow this.
      Signed-off-by: default avatarMasahiro Yamada <yamada.m@jp.panasonic.com>
      Reviewed-by: default avatarSimon Glass <sjg@chromium.org>
      e02ee254
  2. 27 Nov, 2014 1 commit
    • Masahiro Yamada's avatar
      mtd: denali: use CONFIG_SYS_NAND_SELF_INIT · 65e4145a
      Masahiro Yamada authored
      Some variants of the Denali NAND controller need some registers
      set up based on the device information that has been detected during
      nand_scan_ident().
      
      CONFIG_SYS_NAND_SELF_INIT has to be defined to insert code between
      nand_scan_ident() and nand_scan_tail().  It is also helpful to reduce
      the difference between this driver and its Linux counterpart because
      this driver was ported from Linux.  Moreover, doc/README.nand recommends
      to use CONFIG_SYS_NAND_SELF_INIT.
      Signed-off-by: default avatarMasahiro Yamada <yamada.m@jp.panasonic.com>
      Cc: Scott Wood <scottwood@freescale.com>
      Cc: Chin Liang See <clsee@altera.com>
      65e4145a
  3. 05 Oct, 2014 2 commits