Op Wed, 29 Nov 2017 16:23:31 +0100, schreef Stefan Roese:
This patch removes the inclusion of the libgcc math functions and replaces them by functions coded in C, taken from the coreboot project. This makes U-Boot building more independent from the toolchain installed / available on the build system.
Thanks Stefan,
Great work, I'll try to test that soon.
BTW I eventually have been able to work around the problem in Yocto. The work around involved creating a seperate .conf file for u-boot which includes multilib support. I couldn't add multilib support to my rootfs .conf file because that broke building the sdk. Of course the effect is to build a complete seperate target infrastructure (x86_64 + ml) just to build one binary.
This patch will save people a lot of grief I'm sure.
The code taken from coreboot is authored from Vadim Bendebury vbendeb@chromium.org on 2014-11-28 and committed with commit ID e63990ef [libpayload: provide basic 64bit division implementation] (coreboot git repository located here [1]).
I modified the code so that its checkpatch clean without any functional changes.
[1] git://github.com/coreboot/coreboot.git
Signed-off-by: Stefan Roese sr@denx.de Cc: Simon Glass sjg@chromium.org Cc: Bin Meng bmeng.cn@gmail.com
v3:
- Completely get rid of all libgcc references in arch/x86/lib/Makefile, also for the standalone applications
v2:
- Added coreboot git repository link to commit message
arch/x86/config.mk | 3 -- arch/x86/lib/Makefile | 8 +--- arch/x86/lib/div64.c | 113 ++++++++++++++++++++++++++++++++++++++++++++++++++ arch/x86/lib/gcc.c | 29 ------------- 4 files changed, 114 insertions(+), 39 deletions(-) create mode 100644 arch/x86/lib/div64.c delete mode 100644 arch/x86/lib/gcc.c
diff --git a/arch/x86/config.mk b/arch/x86/config.mk index 8835dcf36f..472ada5490 100644 --- a/arch/x86/config.mk +++ b/arch/x86/config.mk @@ -34,9 +34,6 @@ PLATFORM_RELFLAGS += -ffunction-sections -fvisibility=hidden PLATFORM_LDFLAGS += -Bsymbolic -Bsymbolic-functions PLATFORM_LDFLAGS += -m $(if $(IS_32BIT),elf_i386,elf_x86_64)
-LDFLAGS_FINAL += --wrap=__divdi3 --wrap=__udivdi3 -LDFLAGS_FINAL += --wrap=__moddi3 --wrap=__umoddi3 - # This is used in the top-level Makefile which does not include # PLATFORM_LDFLAGS LDFLAGS_EFI_PAYLOAD := -Bsymbolic -Bsymbolic-functions -shared --no-undefined diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile index fe00d7573f..7d729ea0f7 100644 --- a/arch/x86/lib/Makefile +++ b/arch/x86/lib/Makefile @@ -18,7 +18,6 @@ obj-$(CONFIG_SEABIOS) += coreboot_table.o obj-y += early_cmos.o obj-$(CONFIG_EFI) += efi/ obj-y += e820.o -obj-y += gcc.o obj-y += init_helpers.o obj-y += interrupts.o obj-y += lpc-
uclass.o
@@ -49,12 +48,7 @@ endif obj-$(CONFIG_HAVE_FSP) += fsp/ obj-$(CONFIG_SPL_BUILD) += spl.o
-extra-$(CONFIG_USE_PRIVATE_LIBGCC) += lib.a - -NORMAL_LIBGCC = $(shell $(CC) $(PLATFORM_CPPFLAGS) -print-libgcc-file-name) -OBJCOPYFLAGS := --prefix-symbols=__normal_ -$(obj)/lib.a: $(NORMAL_LIBGCC) FORCE - $(call if_changed,objcopy) +lib-$(CONFIG_USE_PRIVATE_LIBGCC) += div64.o
ifeq ($(CONFIG_$(SPL_)X86_64),) obj-$(CONFIG_EFI_APP) += crt0_ia32_efi.o reloc_ia32_efi.o diff --git a/arch/x86/lib/div64.c b/arch/x86/lib/div64.c new file mode 100644 index 0000000000..4efed74037 --- /dev/null +++ b/arch/x86/lib/div64.c @@ -0,0 +1,113 @@ +/*
- This file is copied from the coreboot repository as part of + * the
libpayload project:
- Copyright 2014 Google Inc.
- SPDX-License-Identifier: BSD-3-Clause + */
+#include <common.h>
+union overlay64 {
- u64 longw;
- struct {
u32 lower;u32 higher;- } words;
+};
+u64 __ashldi3(u64 num, unsigned int shift) +{
- union overlay64 output;
- output.longw = num;
- if (shift >= 32) {
output.words.higher = output.words.lower << (shift - 32);
+
output.words.lower = 0;
- } else {
if (!shift)return num;output.words.higher = (output.words.higher << shift) |
+
(output.words.lower >> (32 - shift));
output.words.lower = output.words.lower << shift;- }
- return output.longw;
+}
+u64 __lshrdi3(u64 num, unsigned int shift) +{
- union overlay64 output;
- output.longw = num;
- if (shift >= 32) {
output.words.lower = output.words.higher >> (shift - 32);
+
output.words.higher = 0;
- } else {
if (!shift)return num;output.words.lower = output.words.lower >> shift |
+
(output.words.higher << (32 - shift));
output.words.higher = output.words.higher >> shift;- }
- return output.longw;
+}
+#define MAX_32BIT_UINT ((((u64)1) << 32) - 1)
+static u64 _64bit_divide(u64 dividend, u64 divider, u64 *rem_p) +{
- u64 result = 0;
- /*
* If divider is zero - let the rest of the system care about the
+ *
exception.
*/- if (!divider)
return 1 / (u32)divider;- /* As an optimization, let's not use 64 bit division unless we
must.
*/ + if (dividend <= MAX_32BIT_UINT) {
if (divider > MAX_32BIT_UINT) {result = 0;if (rem_p)*rem_p = divider;} else {result = (u32)dividend / (u32)divider;if (rem_p)*rem_p = (u32)dividend % (u32)divider;}return result;- }
- while (divider <= dividend) {
u64 locald = divider;u64 limit = __lshrdi3(dividend, 1);int shifts = 0;while (locald <= limit) {shifts++;locald = locald + locald;}result |= __ashldi3(1, shifts);dividend -= locald;- }
- if (rem_p)
*rem_p = dividend;- return result;
+}
+u64 __udivdi3(u64 num, u64 den) +{
- return _64bit_divide(num, den, NULL);
+}
+u64 __umoddi3(u64 num, u64 den) +{
- u64 v = 0;
- _64bit_divide(num, den, &v);
- return v;
+} diff --git a/arch/x86/lib/gcc.c b/arch/x86/lib/gcc.c deleted file mode 100644 index 3c70d790d4..0000000000 --- a/arch/x86/lib/gcc.c +++ /dev/null @@ -1,29 +0,0 @@ -/*
- This file is part of the coreboot project.
- Copyright (C) 2009 coresystems GmbH - *
- SPDX-License-Identifier: GPL-2.0 - */
-#ifdef __GNUC__
-/*
- GCC's libgcc handling is quite broken. While the libgcc functions -
- are always regparm(0) the code that calls them uses whatever the - *
compiler call specifies. Therefore we need a wrapper around those - * functions. See gcc bug PR41055 for more information.
- */
-#define WRAP_LIBGCC_CALL(type, name) \
- type __normal_##name(type a, type b) __attribute__((regparm(0)));
\
- type __wrap_##name(type a, type b); \
- type __attribute__((no_instrument_function)) \
__wrap_##name(type a, type b) \{ return __normal_##name(a, b); }-WRAP_LIBGCC_CALL(long long, __divdi3) -WRAP_LIBGCC_CALL(unsigned long long, __udivdi3) -WRAP_LIBGCC_CALL(long long, __moddi3) -WRAP_LIBGCC_CALL(unsigned long long, __umoddi3)
-#endif