@@ -146,6 +146,7 @@ config PPC
select HAVE_ARCH_AUDITSYSCALL
select ARCH_SUPPORTS_ATOMIC_RMW
select DCACHE_WORD_ACCESS if PPC64 && CPU_LITTLE_ENDIAN
+ select BUILD_ELF_V2 if PPC64 && CPU_LITTLE_ENDIAN
select NO_BOOTMEM
select HAVE_GENERIC_RCU_GUP
select HAVE_PERF_EVENTS_NMI if PPC64
@@ -455,6 +456,24 @@ config KEXEC
interface is strongly in flux, so no good recommendation can be
made.
+config BUILD_ELF_V2
+ bool
+
+config BUILD_BIG_ENDIAN_ELF_V2
+ bool "Build big-endian kernel using ELFv2 ABI (EXPERIMENTAL)"
+ depends on PPC64 && CPU_BIG_ENDIAN && EXPERT
+ default n
+ select BUILD_ELF_V2
+ help
+ This builds the kernel image using the ELFv2 ABI, which has a
+ reduced stack overhead and faster function calls. This does not
+ affect the userspace ABIs.
+
+ ELFv2 is the standard ABI for little-endian, but for big-endian
+ this is an experimental option that is not well tested (kernel or
+ toolchain). This requires gcc 4.9 or newer and binutils 2.24 or
+ newer.
+
config RELOCATABLE
bool "Build a relocatable kernel"
depends on (PPC64 && !COMPILE_TEST) || (FLATMEM && (44x || FSL_BOOKE))
@@ -73,10 +73,14 @@ MULTIPLEWORD := -mmultiple
endif
ifdef CONFIG_PPC64
-cflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mabi=elfv1)
-cflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mcall-aixdesc)
-aflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mabi=elfv1)
-aflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mabi=elfv2
+ifdef CONFIG_BUILD_ELF_V2
+cflags-y += $(call cc-option,-mabi=elfv2,$(call cc-option,-mcall-aixdesc))
+aflags-y += $(call cc-option,-mabi=elfv2)
+else
+cflags-y += $(call cc-option,-mabi=elfv1)
+cflags-y += $(call cc-option,-mcall-aixdesc)
+aflags-y += $(call cc-option,-mabi=elfv1)
+endif
endif
cflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mlittle-endian
@@ -116,7 +120,7 @@ endif
endif
CFLAGS-$(CONFIG_PPC64) := $(call cc-option,-mtraceback=no)
-ifeq ($(CONFIG_CPU_LITTLE_ENDIAN),y)
+ifdef CONFIG_BUILD_ELF_V2
CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mabi=elfv2,$(call cc-option,-mcall-aixdesc))
AFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mabi=elfv2)
else
@@ -124,6 +128,7 @@ CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mabi=elfv1)
CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mcall-aixdesc)
AFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mabi=elfv1)
endif
+
CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mcmodel=medium,$(call cc-option,-mminimal-toc))
CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mno-pointers-to-nested-functions)
CFLAGS-$(CONFIG_PPC32) := -ffixed-r2 $(MULTIPLEWORD)
@@ -31,8 +31,10 @@ BOOTCFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
# PPC64_BOOT_WRAPPER is little-endian specific.
ifdef CONFIG_PPC64_BOOT_WRAPPER
BOOTCFLAGS += -m64
+ifdef CONFIG_BUILD_ELF_V2
BOOTCFLAGS += $(call cc-option,-mabi=elfv2)
endif
+endif
ifdef CONFIG_CPU_BIG_ENDIAN
BOOTCFLAGS += -mbig-endian
@@ -1,11 +1,15 @@
obj-$(CONFIG_CRYPTO_DEV_VMX_ENCRYPT) += vmx-crypto.o
vmx-crypto-objs := vmx.o aesp8-ppc.o ghashp8-ppc.o aes.o aes_cbc.o aes_ctr.o aes_xts.o ghash.o
-ifeq ($(CONFIG_CPU_LITTLE_ENDIAN),y)
+ifdef CONFIG_CPU_LITTLE_ENDIAN
TARGET := linux-ppc64le
else
+ifdef CONFIG_BUILD_ELF_V2
+TARGET := linux-ppc64v2
+else
TARGET := linux-ppc64
endif
+endif
quiet_cmd_perl = PERL $@
cmd_perl = $(PERL) $(<) $(TARGET) > $(@)
@@ -61,7 +61,7 @@ if ($flavour =~ /64/) {
$SHL ="slwi";
} else { die "nonsense $flavour"; }
-$LITTLE_ENDIAN = ($flavour=~/le$/) ? $SIZE_T : 0;
+$LITTLE_ENDIAN = ($flavour=~/ppc64le/) ? $SIZE_T : 0;
$0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1;
( $xlate="${dir}ppc-xlate.pl" and -f $xlate ) or
@@ -8,6 +8,8 @@ open STDOUT,">$output" || die "can't open $output: $!";
my %GLOBALS;
my $dotinlocallabels=($flavour=~/linux/)?1:0;
+my $abielfv2=(($flavour =~ /linux-ppc64le/) or ($flavour =~ /linux-ppc64v2/))?1:0;
+my $dotfunctions=($abielfv2=~1)?0:1;
################################################################
# directives which need special treatment on different platforms
@@ -37,9 +39,10 @@ my $globl = sub {
$$global = $name;
$ret;
};
+
my $text = sub {
my $ret = ($flavour =~ /aix/) ? ".csect\t.text[PR],7" : ".text";
- $ret = ".abiversion 2\n".$ret if ($flavour =~ /linux.*64le/);
+ $ret = ".abiversion 2\n".$ret if ($abielfv2);
$ret;
};
my $machine = sub {
@@ -55,8 +58,8 @@ my $size = sub {
if ($flavour =~ /linux/)
{ shift;
my $name = shift; $name =~ s|^[\.\_]||;
- my $ret = ".size $name,.-".($flavour=~/64$/?".":"").$name;
- $ret .= "\n.size .$name,.-.$name" if ($flavour=~/64$/);
+ my $ret = ".size $name,.-".($dotfunctions?".":"").$name;
+ $ret .= "\n.size .$name,.-.$name" if ($dotfunctions);
$ret;
}
else
@@ -141,7 +144,7 @@ my $vmr = sub {
# Some ABIs specify vrsave, special-purpose register #256, as reserved
# for system use.
-my $no_vrsave = ($flavour =~ /linux-ppc64le/);
+my $no_vrsave = ($abielfv2);
my $mtspr = sub {
my ($f,$idx,$ra) = @_;
if ($idx == 256 && $no_vrsave) {
Provide an option to use ELFv2 ABI for big endian builds. The toolchain check can't be done at configure-time, so the way this option is provided can result in unbuildable kernel on older toolchains. Being experimental expert option there isn't a need to add a lot of fallback logic to make this build. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- Hi, Sorry for spamming this patch, kconfig has been more than a match for me. Hopefully 3rd time's a charm. Changes since v1: - Fix kconfig so it (hopefully) works as expected with all combinations of EXPERT and endianness. - Rebased to new "powerpc: allow compilation on cross-endian toolchain" Changes since v2: - Use a big-endian specific config option to avoid silently enabling ELFv2 when switching from LE to BE builds. arch/powerpc/Kconfig | 19 +++++++++++++++++++ arch/powerpc/Makefile | 15 ++++++++++----- arch/powerpc/boot/Makefile | 2 ++ drivers/crypto/vmx/Makefile | 6 +++++- drivers/crypto/vmx/aesp8-ppc.pl | 2 +- drivers/crypto/vmx/ppc-xlate.pl | 11 +++++++---- 6 files changed, 44 insertions(+), 11 deletions(-)