[U-Boot] [RFC PATCH v2 0/28] Create generic board init for ARM, x86, PPC

Simon Glass sjg at chromium.org
Tue Jan 17 07:03:09 CET 2012


Hi,

On Fri, Jan 6, 2012 at 4:24 PM, Simon Glass <sjg at chromium.org> wrote:
> This series creates a generic board.c implementation which contains
> the essential functions of the major arch/xxx/lib/board.c files.

I haven't had huge numbers of comments on this series, but there are a
few. I plan to tidy these up and resubmit, dropping the RFC tag,
sometime this week.

Any patches / fixes to make this run properly on x86 / PPC would be
gratefully accepted.

Regards,
Simon

>
> What is the motivation for this change?
>
> 1. There is a lot of repeated code in the board.c files. Any change to
> things like setting up the baud rate requires a change in 10 separate
> places.
>
> 2. Since there are 10 separate files, adding a new feature which requires
> initialisation is painful since it must be independently added in 10
> places.
>
> 3. As time goes by the architectures naturely diverge since there is limited
> pressure to compare features or even CONFIG options against simiilar things
> in other board.c files.
>
> 4. New architectures must implement all the features all over again, and
> sometimes in subtley different ways. This places an unfair burden on getting
> a new architecture fully functional and running with U-Boot.
>
> 5. While it is a bit of a tricky change, I believe it is worthwhile and
> achievable. There is no requirement that all code be common, only that
> the code that is common should be located in common/board.c rather than
> arch/xxx/lib/board.c.
>
> All the functions of board_init_f() and board_init_r() are broken into
> separate function calls so that they can easily be included or excluded
> for a particular architecture. It also makes it easier to adopt Graeme's
> initcall proposal when it is ready.
>
> http://lists.denx.de/pipermail/u-boot/2012-January/114499.html
>
> This series removes the dependency on generic relocation. So relocation
> happens as one big chunk and is still completely arch-specific. See the
> relocation series for a proposed solution to this for ARM:
>
> http://lists.denx.de/pipermail/u-boot/2011-December/112928.html
>
> or Graeme's recent x86 series v2:
>
> http://lists.denx.de/pipermail/u-boot/2012-January/114467.html
>
> Instead of moving over a whole architecture, this series takes the approach
> of simply enabling generic board support for an architecture. It is then up
> to each board to opt in by defining CONFIG_SYS_GENERIC_BOARD in the board
> config file. If this is not done, then the code will be generated as
> before. This allows both sets of code to co-exist until we are comfortable
> with the generic approach, and enough boards run.
>
> ARM is a relatively large board.c file and one which I can test, therefore
> I think it is a good target for this series. On the other hand, x86 is
> relatively small and simple, but different enough that it introduces a
> few issues to be solved. So I have chosen both ARM and x86 for this series.
> After a suggestion from Wolfgang I have added PPC also. This is the
> largest and most feature-full board, so hopefully we have all bases
> covered in this RFC.
>
> A generic global_data structure is also required. This might upset a few
> people. Here is my basic reasoning: most fields are the same, all
> architectures include and need it, most global_data.h files already have
>  #ifdefs to select fields for a particular SOC, so it is hard to
> see why architecures are different in this area. We can perhaps add a
> way to put architecture-specific fields into a separate header file, but
> for now I have judged that to be counter-productive.
>
> Similarly we need a generic bd_info structure, since generic code will
> be accessing it. I have done this in the same way as global_data and the
> same comments apply.
>
> There was dicussion on the list about passing gd_t around as a parameter
> to pre-relocation init functions. I think this makes sense, but it can
> be done as a separate change, and this series does not require it.
>
> While this series needs to stand on its own (as with the link script
> cleanup series and the generic relocation series) the goal is the
> unification of the board init code. So I hope we can address issues with
> this in mind, rather than focusing too narrowly on particular ARM, x86 or
> PPC issues.
>
> I have run-tested ARM on Tegra Seaboard only. To try it out, define
> CONFIG_SYS_GENERIC_BOARD in your board file and rebuild. Most likely on
> x86 and PPC at least it will hang, but if you are lucky it will print
> something first :-)
>
> I have run this though MAKEALL with CONFIG_SYS_GENERIC_BOARD on for all
> ARM, PPC and x86 boards. There are a few failures, some due to errors in
> the board config, some due to things that need fixing. I will address
> these with the final series if required.
>
> Note: the first group of commits are required for this series to build,
> but could be separated out if required. I have included them here for
> convenience.
>
> Comments welcome.
>
> Changes in v2:
> - Change generic board to an opt-in system on a per-board basic
> - Add CONFIG_SYS_GENERIC_BOARD to allow board to select generic board
> - Add PowerPC support
> - Rebase to master
>
> Simon Glass (28):
>  arm: Change board baud_rate to ulong
>  x86: Change board baud_rate to ulong
>  arm: Only display frame buffer info if there is LCD/video support
>  x86: Remove compiler warning in sc520_timer.c
>  x86: Remove dead code in eNET
>  x86: Add initial memory barrier macros
>  ppc: Add initial memory barrier macros
>  Introduce generic global_data
>  Introduce generic u-boot.h file
>  Introduce generic link symbol file
>  arm: Use sections header to obtain link symbols
>  x86: Change stub example to use asm-generic/sections.h
>  Introduce a basic initcall implementation
>  Define CONFIG_SYS_LEGACY_BOARD everywhere
>  Introduce generic pre-relocation board_f.c
>  Introduce generic post-relocation board_r.c
>  Add spl load feature
>  arm: Enable generic board support
>  Add CONFIG_SYS_SYM_OFFSETS to support offset symbols
>  x86: Use sections header to obtain link symbols
>  Add x86 fields to generic global_data
>  x86: Enable generic board support
>  Add ppc fields to generic global data
>  Adjust board_f for ppc
>  Adjust board_r.c for PowerPC
>  ppc: Enable generic board board
>  tegra: Mark board init files for ARMv4t
>  tegra: Enable generic board for Seaboard.
>
>  README                                 |   17 +
>  arch/arm/cpu/armv7/tegra2/config.mk    |    2 +
>  arch/arm/include/asm/global_data.h     |    7 +
>  arch/arm/include/asm/u-boot-arm.h      |    4 -
>  arch/arm/include/asm/u-boot.h          |   11 +-
>  arch/arm/lib/Makefile                  |    4 +-
>  arch/arm/lib/board.c                   |    1 +
>  arch/avr32/config.mk                   |    3 +
>  arch/blackfin/config.mk                |    3 +
>  arch/m68k/config.mk                    |    3 +
>  arch/microblaze/config.mk              |    3 +
>  arch/mips/config.mk                    |    3 +
>  arch/nds32/config.mk                   |    3 +
>  arch/nios2/config.mk                   |    3 +
>  arch/powerpc/include/asm/global_data.h |    7 +
>  arch/powerpc/include/asm/io.h          |    8 +
>  arch/powerpc/include/asm/u-boot.h      |    7 +
>  arch/powerpc/lib/Makefile              |    4 +-
>  arch/sandbox/config.mk                 |    3 +
>  arch/sh/config.mk                      |    3 +
>  arch/sparc/config.mk                   |    3 +
>  arch/x86/cpu/sc520/sc520_timer.c       |    2 +-
>  arch/x86/include/asm/global_data.h     |    7 +
>  arch/x86/include/asm/io.h              |    8 +
>  arch/x86/include/asm/u-boot-x86.h      |    8 -
>  arch/x86/include/asm/u-boot.h          |   13 +-
>  arch/x86/lib/Makefile                  |    4 +-
>  arch/x86/lib/board.c                   |    1 +
>  board/cm4008/flash.c                   |    1 +
>  board/cm41xx/flash.c                   |    1 +
>  board/eNET/eNET.c                      |    5 -
>  common/Makefile                        |    4 +
>  common/board_f.c                       |  888 ++++++++++++++++++++++++++++++++
>  common/board_r.c                       |  863 +++++++++++++++++++++++++++++++
>  common/cmd_bdinfo.c                    |    6 +-
>  config.mk                              |    8 +
>  examples/standalone/stubs.c            |    7 +-
>  include/asm-generic/global_data.h      |  241 +++++++++
>  include/asm-generic/sections.h         |  124 +++++
>  include/asm-generic/u-boot.h           |  155 ++++++
>  include/common.h                       |   16 +
>  include/configs/seaboard.h             |    2 +
>  include/initcall.h                     |   25 +
>  lib/Makefile                           |    1 +
>  lib/initcall.c                         |   41 ++
>  45 files changed, 2504 insertions(+), 29 deletions(-)
>  create mode 100644 common/board_f.c
>  create mode 100644 common/board_r.c
>  create mode 100644 include/asm-generic/global_data.h
>  create mode 100644 include/asm-generic/sections.h
>  create mode 100644 include/asm-generic/u-boot.h
>  create mode 100644 include/initcall.h
>  create mode 100644 lib/initcall.c
>
> --
> 1.7.3.1
>


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