[U-Boot] [PATCH 4/4] x86: Remove 16-bit reset code

[Graeme Russ]

Hi Simon,

On Sat, Feb 9, 2013 at 3:42 AM, Simon Glass <sjg at chromium.org> wrote:
> This code is not needed now, since we boot U-Boot from Coreboot on x86.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>  Makefile                   |   4 --
>  README                     |   4 --
>  arch/x86/cpu/Makefile      |   1 -
>  arch/x86/cpu/resetvec.S    |  38 ------------
>  arch/x86/cpu/start16.S     | 146 ---------------------------------------------
>  include/configs/coreboot.h |   1 -
>  6 files changed, 194 deletions(-)
>  delete mode 100644 arch/x86/cpu/resetvec.S
>  delete mode 100644 arch/x86/cpu/start16.S

As mentioned in reply to the previous patch, I would like to see this code stay

> diff --git a/Makefile b/Makefile
> index 51bd918..1924d4b 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -230,10 +230,6 @@ endif
>  # U-Boot objects....order is important (i.e. start must be first)
>
>  OBJS  = $(CPUDIR)/start.o
> -ifeq ($(CPU),x86)
> -RESET_OBJS-$(CONFIG_X86_NO_RESET_VECTOR) += $(CPUDIR)/start16.o
> -RESET_OBJS-$(CONFIG_X86_NO_RESET_VECTOR) += $(CPUDIR)/resetvec.o
> -endif

Hmm, odd - the logic here seems to be inverted - the reset vector code
appears to be included if CONFIG_X86_NO_RESET_VECTOR is defined...

Oh, and as discussed before, this can actually be moved out of the
main Makefile and into arch/x86/cpu/Makefile. Hmm, that's odd, it
looks like it already is:

START-y = start.o
RESET_OBJS-$(CONFIG_X86_NO_RESET_VECTOR) += resetvec.o start16.o
COBJS   = interrupts.o cpu.o timer.o

SRCS    := $(START:.o=.S) $(SOBJS:.o=.S) $(COBJS:.o=.c)
OBJS    := $(addprefix $(obj),$(SOBJS) $(COBJS))
START   := $(addprefix $(obj),$(START-y) $(RESET_OBJS-))

But again, the logic seems to be inverted...

> diff --git a/README b/README
> index 103036f..061898c 100644
> --- a/README
> +++ b/README
> @@ -3816,10 +3816,6 @@ Low Level (hardware related) configuration options:
>                 be used if available. These functions may be faster under some
>                 conditions but may increase the binary size.
>
> -- CONFIG_X86_NO_RESET_VECTOR
> -               If defined, the x86 reset vector code is excluded. You will need
> -               to do this when U-Boot is running from Coreboot.
> -

Maybe we could just change this to CONFIG_X86_RESET_VECTOR and make
exclusion of the 16-bit reset vector and protected mode switch the
default case

Regards,

Graeme