[PATCH] microblaze: Enable GCC garbage collector for full U-Boot

[Michal Simek]

st 4. 11. 2020 v 14:55 odesílatel Michal Simek <michal.simek at xilinx.com> napsal:
>
> GCC's garbage collector works for Microblaze for quite a long time but none
> has enabled it.
> The same change has be done for example by commit fac4790491f6 ("arc:
> Eliminate unused code and data with GCC's garbage collector").
>
> Before:
>    text    data     bss     dec     hex filename
>  588760   33592   39192  661544   a1828 u-boot
>
> After:
>    text    data     bss     dec     hex filename
>  504504   32164   38608  575276   8c72c u-boot
>
> Which saves almost 15% of memory footprint.
>
> Also group symbols/functions to proper section.
>
> Reported-by: Tom Rini <trini at konsulko.com>
> Signed-off-by: Michal Simek <michal.simek at xilinx.com>
> ---
>
>  arch/microblaze/config.mk      | 3 +++
>  arch/microblaze/cpu/u-boot.lds | 6 +++---
>  2 files changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/arch/microblaze/config.mk b/arch/microblaze/config.mk
> index 96c39b1278b1..de5b97e719cc 100644
> --- a/arch/microblaze/config.mk
> +++ b/arch/microblaze/config.mk
> @@ -9,6 +9,9 @@
>  CONFIG_STANDALONE_LOAD_ADDR ?= 0x80F00000
>
>  PLATFORM_CPPFLAGS += -ffixed-r31 -D__microblaze__
> +PLATFORM_CPPFLAGS += -fdata-sections -ffunction-sections
> +
> +LDFLAGS_FINAL += --gc-sections
>
>  ifeq ($(CONFIG_SPL_BUILD),)
>  PLATFORM_CPPFLAGS += -fPIC
> diff --git a/arch/microblaze/cpu/u-boot.lds b/arch/microblaze/cpu/u-boot.lds
> index 928264334989..5dc09dbad2df 100644
> --- a/arch/microblaze/cpu/u-boot.lds
> +++ b/arch/microblaze/cpu/u-boot.lds
> @@ -14,7 +14,7 @@ SECTIONS
>         {
>                 __text_start = .;
>                 arch/microblaze/cpu/start.o (.text)
> -               *(.text)
> +               *(.text*)
>                 __text_end = .;
>         }
>
> @@ -28,7 +28,7 @@ SECTIONS
>         .data ALIGN(0x4):
>         {
>                 __data_start = .;
> -               *(.data)
> +               *(.data*)
>                 __data_end = .;
>         }
>
> @@ -51,7 +51,7 @@ SECTIONS
>                 __bss_start = .;
>                 *(.sbss)
>                 *(.scommon)
> -               *(.bss)
> +               *(.bss*)
>                 *(COMMON)
>                 . = ALIGN(4);
>                 __bss_end = .;
> --
> 2.29.2
>

Applied.
M

-- 
Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91
w: www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel - Xilinx Microblaze
Maintainer of Linux kernel - Xilinx Zynq ARM and ZynqMP ARM64 SoCs
U-Boot custodian - Xilinx Microblaze/Zynq/ZynqMP/Versal SoCs