[U-Boot] [PATCH 19/39] x86: Build a .rom file which can be flashed to an x86 machine

[Bin Meng]

Hi Simon,

On Fri, Nov 7, 2014 at 4:20 AM, Simon Glass <sjg at chromium.org> wrote:
> On x86 machines U-Boot needs to be added to a large ROM image which is
> then flashed onto the target board. The ROM has a particular format so it
> makes sense for U-Boot to build this image automatically. Unfortunately
> it relies on binary blobs so we cannot require this for the default
> build as yet.
>
> Create a u-boot.rom output file for this purpose.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
>  Makefile                          | 27 ++++++++++++++++++++++++++-
>  arch/x86/Kconfig                  |  4 ++++
>  include/configs/chromebook_link.h |  2 ++
>  3 files changed, 32 insertions(+), 1 deletion(-)
>
> diff --git a/Makefile b/Makefile
> index 9c8a580..86d0510 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -743,6 +743,9 @@ ALL-$(CONFIG_SPL) += $(CONFIG_SPL_TARGET:"%"=%)
>  endif
>  ALL-$(CONFIG_REMAKE_ELF) += u-boot.elf
>
> +# We can't do this yet due to the need for binary blobs
> +# ALL-$(CONFIG_X86_RESET_VECTOR) += u-boot.rom
> +
>  # enable combined SPL/u-boot/dtb rules for tegra
>  ifneq ($(CONFIG_TEGRA),)
>  ifeq ($(CONFIG_SPL),y)
> @@ -804,7 +807,8 @@ OBJCOPYFLAGS_u-boot.srec := -O srec
>  u-boot.hex u-boot.srec: u-boot FORCE
>         $(call if_changed,objcopy)
>
> -OBJCOPYFLAGS_u-boot.bin := -O binary
> +OBJCOPYFLAGS_u-boot.bin := -O binary \
> +               $(if $(CONFIG_X86_RESET_VECTOR),-R .start16 -R .resetvec)
>
>  binary_size_check: u-boot.bin FORCE
>         @file_size=$(shell wc -c u-boot.bin | awk '{print $$1}') ; \
> @@ -943,6 +947,27 @@ u-boot-nand.gph: u-boot.bin FORCE
>         $(call if_changed,mkimage)
>         @dd if=/dev/zero bs=8 count=1 2>/dev/null >> $@
>
> +# x86 uses a large ROM. We fill it with 0xff, put the 16-bit stuff (including
> +# reset vector) at the top, Intel ME at the bottom, and U-Boot in the middle.
> +ifneq ($(CONFIG_X86_RESET_VECTOR),)
> +rom: u-boot.rom FORCE
> +
> +u-boot.rom: u-boot-x86-16bit.bin u-boot-dtb.bin \

The u-boot-dtb.bin means we have to use device tree for all x86 board
port. Is this a must-have?

> +               $(srctree)/board/$(BOARDDIR)/descriptor.bin

I don't see where the descriptor.bin is created?

> +       $(objtree)/tools/ifdtool -c -r $(CONFIG_ROM_SIZE) \
> +               -D $(srctree)/board/$(BOARDDIR)/descriptor.bin u-boot.tmp
> +       $(objtree)/tools/ifdtool -w \
> +               $(CONFIG_SYS_TEXT_BASE):$(objtree)/u-boot-dtb.bin u-boot.tmp
> +       $(objtree)/tools/ifdtool -w \
> +               $(CONFIG_SYS_X86_START16):$(objtree)/u-boot-x86-16bit.bin \
> +               u-boot.tmp
> +       mv u-boot.tmp $@
> +
> +OBJCOPYFLAGS_u-boot-x86-16bit.bin := -O binary -j .start16 -j .resetvec
> +u-boot-x86-16bit.bin: u-boot FORCE
> +       $(call if_changed,objcopy)
> +endif
> +

[snip]

Regards,
Bin