New patch to review for coreboot: x86/bootblock: Use LDFLAGS_bootblock to enable garbage collection

[Alexandru Gagniuc]

Alexandru Gagniuc ([e-mail]) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/11781

-gerrit

commit 66c50e7720d20c2964a4cfefa254148d7b22449f
Author: Alexandru Gagniuc 
Date:   Fri Oct 2 10:59:13 2015 -0700

x86/bootblock: Use LDFLAGS_bootblock to enable garbage collection

The x86 bootblock linking is a mess. The bootblock is treated in
    a very special manner, and never received the update to link-time
    garbage collection.

On newer x86 platforms, the boot media is no longer memory-mapped.
    That means we need to do a lot more setup in the bootblock. ROMCC is
    unsuitable for this task, and walkcbfs only works on memory-mapped
    CBFS. We need to revise the x86 bootflow for this new case.

The approach this patch series takes is to perform CAR setup in the
    bootblock, and load the following stage (either romstage or verstage)
    from the boot media. This approach is not new, but has been done on
    our ARM ports for years.

Since we will be adding .c files to the bootblock, it is prudent to
    use link-time garbage collection. This is also consistent to how we
    do things on other architectures. Unification FTW!

Change-Id: I16b78456df56e0053984a9aca9367e2542adfdc9
    Signed-off-by: Alexandru Gagniuc 
---
 src/arch/x86/Makefile.inc    | 4 ++--
 src/arch/x86/id.ld           | 2 +-
 src/cpu/intel/fit/fit.ld     | 2 +-
 src/cpu/x86/16bit/reset16.ld | 2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/arch/x86/Makefile.inc b/src/arch/x86/Makefile.inc
index f16edcd..1bda5f6 100644
--- a/src/arch/x86/Makefile.inc
+++ b/src/arch/x86/Makefile.inc
@@ -106,9 +106,9 @@ $(objgenerated)/bootblock.inc: $(src)/arch/x86/$(subst ",,$(CONFIG_BOOTBLOCK_SOU
 $(objcbfs)/bootblock.debug: $(obj)/arch/x86/bootblock.bootblock.o $(obj)/arch/x86/bootblock.bootblock.ld
    @printf "    LINK       $(subst $(obj)/,,$(@))\n"
 ifeq ($(CONFIG_ARCH_BOOTBLOCK_X86_32),y)
-	$(LD_bootblock) -m elf_i386 --oformat elf32-i386 -static -o $@ -L$(obj) $< -T $(obj)/arch/x86/bootblock.bootblock.ld
+	$(LD_bootblock) $(LDFLAGS_common) -m elf_i386 --oformat elf32-i386 -static -o $@ -L$(obj) $< -T $(obj)/arch/x86/bootblock.bootblock.ld
 else
-	$(LD_bootblock) -m elf_x86_64 --oformat elf64-x86-64 -static -o $@ -L$(obj) $< -T $(obj)/arch/x86/bootblock.bootblock.ld
+	$(LD_bootblock) $(LDFLAGS_common) -m elf_x86_64 --oformat elf64-x86-64 -static -o $@ -L$(obj) $< -T $(obj)/arch/x86/bootblock.bootblock.ld
 endif

diff --git a/src/arch/x86/id.ld b/src/arch/x86/id.ld
index cfd091d..99d13f1 100644
--- a/src/arch/x86/id.ld
+++ b/src/arch/x86/id.ld
@@ -1,6 +1,6 @@
 SECTIONS {
    . = (0xffffffff - CONFIG_ID_SECTION_OFFSET) - (__id_end - __id_start) + 1;
    .id (.): {
-		*(.id)
+		KEEP(*(.id))
    }
 }
diff --git a/src/cpu/intel/fit/fit.ld b/src/cpu/intel/fit/fit.ld
index 9ccfe82..5817e1d 100644
--- a/src/cpu/intel/fit/fit.ld
+++ b/src/cpu/intel/fit/fit.ld
@@ -1,6 +1,6 @@
 SECTIONS {
    . = 0xffffffc0;
    .fit_pointer (.): {
-		*(.fit_pointer)
+		KEEP(*(.fit_pointer))
    }
 }
diff --git a/src/cpu/x86/16bit/reset16.ld b/src/cpu/x86/16bit/reset16.ld
index a31a580..d0c4096 100644
--- a/src/cpu/x86/16bit/reset16.ld
+++ b/src/cpu/x86/16bit/reset16.ld
@@ -9,7 +9,7 @@ SECTIONS {
    _ROMTOP = 0xfffffff0;
    . = _ROMTOP;
    .reset . : {
-		*(.reset)
+		KEEP(*(.reset));
    	. = 15 ;
    	BYTE(0x00);
    }