| Message ID | 20171129152331.2458-1-sr@denx.de |
|---|---|
| State | Accepted |
| Commit | aa7839b39c2ee77f9ab8c393c56b8d812507dbb7 |
| Delegated to: | Bin Meng |
| Headers | show |
| Series | [U-Boot,v3] x86: lib: Implement standalone __udivdi3 etc instead of libgcc ones | expand |
On Wed, Nov 29, 2017 at 11:23 PM, Stefan Roese <sr@denx.de> wrote: > 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. > > 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 > Reviewed-by: Bin Meng <bmeng.cn@gmail.com> Tested-by: Bin Meng <bmeng.cn@gmail.com>
On Thu, Nov 30, 2017 at 1:31 PM, Bin Meng <bmeng.cn@gmail.com> wrote: > On Wed, Nov 29, 2017 at 11:23 PM, Stefan Roese <sr@denx.de> wrote: >> 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. >> >> 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 >> > > Reviewed-by: Bin Meng <bmeng.cn@gmail.com> > Tested-by: Bin Meng <bmeng.cn@gmail.com> applied to u-boot-x86, thanks!
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
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
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. 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