From f69a99dbf843da7f4c2b4965004140d2ea83cd67 Mon Sep 17 00:00:00 2001 From: Aaron Durbin Date: Tue, 10 Mar 2015 11:45:25 -0500 Subject: coreboot: x86: enable gc-sections Garbage collected sections allow for trimming the size of the binaries as well as allowing for not needing to config off unused functions. To that end, on a rambi build the following differences are observed: $ diff -up \ <(readelf -l coreboot-builds/google_rambi/cbfs/fallback/ramstage.elf) \ <(readelf -l coreboot-builds/google_rambi_gc_sections/cbfs/fallback/ramstage.elf) --- /dev/fd/63 2015-03-10 12:07:27.927985430 -0500 +++ /dev/fd/62 2015-03-10 12:07:27.927985430 -0500 @@ -6,9 +6,9 @@ There are 4 program headers, starting at Program Headers: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align LOAD 0x001000 0x00000000 0x00000000 0x00040 0x00040 RWE 0 - LOAD 0x001040 0x00000040 0x00000040 0x34560 0x34560 RWE 0 - LOAD 0x0355a0 0x000345a0 0x000345a0 0x02578 0x02578 RWE 0 - LOAD 0x037b18 0x00036b18 0x00036b18 0x00000 0x0b560 0 + LOAD 0x001040 0x00000040 0x00000040 0x2cbf8 0x2cbf8 RWE 0 + LOAD 0x02dc38 0x0002cc38 0x0002cc38 0x02208 0x02208 RWE 0 + LOAD 0x02fe40 0x0002ee40 0x0002ee40 0x00000 0x0a888 0 Section to Segment mapping: Segment Sections... $ diff -up \ <(readelf -l coreboot-builds/google_rambi/cbfs/fallback/romstage.elf) \ <(readelf -l coreboot-builds/google_rambi_gc_sections/cbfs/fallback/romstage.elf) --- /dev/fd/63 2015-03-10 12:08:16.855985880 -0500 +++ /dev/fd/62 2015-03-10 12:08:16.851985880 -0500 @@ -5,8 +5,8 @@ There are 1 program headers, starting at Program Headers: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align - LOAD 0x000060 0xfff20000 0xfff20000 0x08b81 0x08b81 R E 0x10 + LOAD 0x000060 0xfff20000 0xfff20000 0x06300 0x06300 R E 0x10 Section to Segment mapping: Segment Sections... - 00 .rom .text + 00 .rom The following warnings needed to be applied to CFLAGS_common because for some reason gcc was miraculously emitting the warnings with the unrelated *-sections options: -Wno-unused-but-set-variable Change-Id: I210784fdfc273ce4cb9927352cbd5a51be3c6929 Signed-off-by: Aaron Durbin Reviewed-on: http://review.coreboot.org/8635 Tested-by: build bot (Jenkins) Reviewed-by: Patrick Georgi Reviewed-by: Paul Menzel --- src/arch/x86/ramstage.ld | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) (limited to 'src/arch/x86/ramstage.ld') diff --git a/src/arch/x86/ramstage.ld b/src/arch/x86/ramstage.ld index 1c8e8dcd6f..0843be7906 100644 --- a/src/arch/x86/ramstage.ld +++ b/src/arch/x86/ramstage.ld @@ -42,7 +42,7 @@ SECTIONS .ctors : { . = ALIGN(0x100); __CTOR_LIST__ = .; - *(.ctors); + KEEP(*(.ctors)); LONG(0); __CTOR_END__ = .; } @@ -55,13 +55,13 @@ SECTIONS * section names the equivalent changes need to made to * rmodule.ld. */ pci_drivers = . ; - *(.rodata.pci_driver) + KEEP(*(.rodata.pci_driver)); epci_drivers = . ; cpu_drivers = . ; - *(.rodata.cpu_driver) + KEEP(*(.rodata.cpu_driver)); ecpu_drivers = . ; _bs_init_begin = .; - *(.bs_init) + KEEP(*(.bs_init)); _bs_init_end = .; *(.rodata) @@ -82,6 +82,7 @@ SECTIONS .data : { _data = .; *(.data) + *(.data.*) _edata = .; } @@ -92,7 +93,9 @@ SECTIONS _bss = .; .bss . : { *(.bss) + *(.bss.*) *(.sbss) + *(.sbss.*) *(COMMON) } _ebss = .; -- cgit v1.2.3