Ping? Is this patch acceptable for merging?
Cheers, Kyle Moffett On Oct 18, 2011, at 17:16, Moffett, Kyle D wrote: > Standard Debian powerpc and powerpcspe systems only include hard-float > libgcc in their native compilers, which causes scary build warnings when > building U-Boot. > > While U-Boot does not use floating point at all, it is perfectly legal > for a hard-float libgcc to use features of the floating point unit to > implement 64-bit divides and shifts. Since U-Boot does not set up the > floating point unit or initialize the registers, that could cause > crashes or other misbehavior. > > In particular, on e500 systems with SPE extensions, a "hard-float" > libgcc might use the top half of the "extended" 64-bit registers for > various 64-bit shifts and other operations, which is probably unsafe. > > To avoid a dependency on "nof" (IE: soft-float) libgcc provided by the > system toolchain, U-Boot should be able to provide its own copies of the > necessary routines just like the Linux kernel does. In particular, this > resolves build failures on native Debian PowerPC systems which no longer > provide any soft-float libraries in the system toolchain. > > This patch provides an implementation of USE_PRIVATE_LIBGCC=yes from the > Linux Kernel that matches what the ARM architecture implements in > assembly files in arch/arm/lib/*.S > > Specifically, the routines are: _ashldi3(), _ashrdi3(), and _lshrdi3(). > They were borrowed from arch/powerpc/kernel/misc_32.S as of v2.6.38-rc5, > commit 85e2efbb1db9a18d218006706d6e4fbeb0216213, and are GPLv2+. > > The Makefile framework was copied from the U-Boot ARM port. > > Signed-off-by: Kyle Moffett <kyle.d.moff...@boeing.com> > Cc: Wolfgang Denk <w...@denx.de> > Cc: Kim Phillips <kim.phill...@freescale.com> > Cc: Andy Fleming <aflem...@gmail.com> > Cc: Kumar Gala <kumar.g...@freescale.com> > Cc: Stefan Roese <s...@denx.de> > > --- > > I believe I have addressed all of the previous questions regarding > this patch with an updated commit message. Can this be merged? > > Cheers, > Kyle Moffett > > -- > Curious about my work on the Debian powerpcspe port? > I'm keeping a blog here: http://pureperl.blogspot.com/ > --- > arch/powerpc/lib/Makefile | 23 ++++++++++++++++++++- > arch/powerpc/lib/_ashldi3.S | 45 +++++++++++++++++++++++++++++++++++++++++ > arch/powerpc/lib/_ashrdi3.S | 47 +++++++++++++++++++++++++++++++++++++++++++ > arch/powerpc/lib/_lshrdi3.S | 45 +++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 159 insertions(+), 1 deletions(-) > create mode 100644 arch/powerpc/lib/_ashldi3.S > create mode 100644 arch/powerpc/lib/_ashrdi3.S > create mode 100644 arch/powerpc/lib/_lshrdi3.S > > diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile > index 724d8ee..cdd62a2 100644 > --- a/arch/powerpc/lib/Makefile > +++ b/arch/powerpc/lib/Makefile > @@ -23,6 +23,19 @@ > > include $(TOPDIR)/config.mk > > +## Build a couple of necessary functions into a private libgcc > +LIBGCC = $(obj)libgcc.o > +GLSOBJS += _ashldi3.o > +GLSOBJS += _ashrdi3.o > +GLSOBJS += _lshrdi3.o > +LGOBJS := $(addprefix $(obj),$(GLSOBJS)) \ > + $(addprefix $(obj),$(GLCOBJS)) > + > +## But only build it if the user asked for it > +ifdef USE_PRIVATE_LIBGCC > +TARGETS += $(LIBGCC) > +endif > + > LIB = $(obj)lib$(ARCH).o > > SOBJS-y += ppccache.o > @@ -53,9 +66,14 @@ endif > > COBJS += $(sort $(COBJS-y)) > > -SRCS := $(SOBJS-y:.o=.S) $(COBJS-y:.o=.c) > +SRCS := $(GLSOBJS:.o=.S) $(GLCOBJS:.o=.c) \ > + $(SOBJS-y:.o=.S) $(COBJS-y:.o=.c) > OBJS := $(addprefix $(obj),$(SOBJS-y) $(COBJS-y)) > > +TARGETS += $(LIB) > + > +all: $(TARGETS) > + > $(LIB): $(obj).depend $(OBJS) > @if ! $(CROSS_COMPILE)readelf -S $(OBJS) | grep -q '\.fixup.*PROGBITS';\ > then \ > @@ -65,6 +83,9 @@ $(LIB): $(obj).depend $(OBJS) > fi; > $(call cmd_link_o_target, $(OBJS)) > > +$(LIBGCC): $(obj).depend $(LGOBJS) > + $(call cmd_link_o_target, $(LGOBJS)) > + > ######################################################################### > > # defines $(obj).depend target > diff --git a/arch/powerpc/lib/_ashldi3.S b/arch/powerpc/lib/_ashldi3.S > new file mode 100644 > index 0000000..e452f56 > --- /dev/null > +++ b/arch/powerpc/lib/_ashldi3.S > @@ -0,0 +1,45 @@ > +/* > + * This code was copied from arch/powerpc/kernel/misc_32.S in the Linux > + * kernel sources (commit 85e2efbb1db9a18d218006706d6e4fbeb0216213, also > + * known as 2.6.38-rc5). The source file copyrights are as follows: > + * > + * (C) Copyright 1995-1996 Gary Thomas (g...@linuxppc.org) > + * > + * Largely rewritten by Cort Dougan (c...@cs.nmt.edu) > + * and Paul Mackerras. > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License as > + * published by the Free Software Foundation; either version 2 of > + * the License, or (at your option) any later version. > + */ > + > +#include <ppc_asm.tmpl> > +#include <ppc_defs.h> > +#include <config.h> > + > +/* > + * Extended precision shifts. > + * > + * Updated to be valid for shift counts from 0 to 63 inclusive. > + * -- Gabriel > + * > + * R3/R4 has 64 bit value > + * R5 has shift count > + * result in R3/R4 > + * > + * ashrdi3: arithmetic right shift (sign propagation) > + * lshrdi3: logical right shift > + * ashldi3: left shift > + */ > + .globl __ashldi3 > +__ashldi3: > + subfic r6,r5,32 > + slw r3,r3,r5 # MSW = count > 31 ? 0 : MSW << count > + addi r7,r5,32 # could be xori, or addi with -32 > + srw r6,r4,r6 # t1 = count > 31 ? 0 : LSW >> (32-count) > + slw r7,r4,r7 # t2 = count < 32 ? 0 : LSW << (count-32) > + or r3,r3,r6 # MSW |= t1 > + slw r4,r4,r5 # LSW = LSW << count > + or r3,r3,r7 # MSW |= t2 > + blr > diff --git a/arch/powerpc/lib/_ashrdi3.S b/arch/powerpc/lib/_ashrdi3.S > new file mode 100644 > index 0000000..f28ab49 > --- /dev/null > +++ b/arch/powerpc/lib/_ashrdi3.S > @@ -0,0 +1,47 @@ > +/* > + * This code was copied from arch/powerpc/kernel/misc_32.S in the Linux > + * kernel sources (commit 85e2efbb1db9a18d218006706d6e4fbeb0216213, also > + * known as 2.6.38-rc5). The source file copyrights are as follows: > + * > + * (C) Copyright 1995-1996 Gary Thomas (g...@linuxppc.org) > + * > + * Largely rewritten by Cort Dougan (c...@cs.nmt.edu) > + * and Paul Mackerras. > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License as > + * published by the Free Software Foundation; either version 2 of > + * the License, or (at your option) any later version. > + */ > + > +#include <ppc_asm.tmpl> > +#include <ppc_defs.h> > +#include <config.h> > + > +/* > + * Extended precision shifts. > + * > + * Updated to be valid for shift counts from 0 to 63 inclusive. > + * -- Gabriel > + * > + * R3/R4 has 64 bit value > + * R5 has shift count > + * result in R3/R4 > + * > + * ashrdi3: arithmetic right shift (sign propagation) > + * lshrdi3: logical right shift > + * ashldi3: left shift > + */ > + .globl __ashrdi3 > +__ashrdi3: > + subfic r6,r5,32 > + srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count > + addi r7,r5,32 # could be xori, or addi with -32 > + slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count) > + rlwinm r8,r7,0,32 # t3 = (count < 32) ? 32 : 0 > + sraw r7,r3,r7 # t2 = MSW >> (count-32) > + or r4,r4,r6 # LSW |= t1 > + slw r7,r7,r8 # t2 = (count < 32) ? 0 : t2 > + sraw r3,r3,r5 # MSW = MSW >> count > + or r4,r4,r7 # LSW |= t2 > + blr > diff --git a/arch/powerpc/lib/_lshrdi3.S b/arch/powerpc/lib/_lshrdi3.S > new file mode 100644 > index 0000000..c1bbe7b > --- /dev/null > +++ b/arch/powerpc/lib/_lshrdi3.S > @@ -0,0 +1,45 @@ > +/* > + * This code was copied from arch/powerpc/kernel/misc_32.S in the Linux > + * kernel sources (commit 85e2efbb1db9a18d218006706d6e4fbeb0216213, also > + * known as 2.6.38-rc5). The source file copyrights are as follows: > + * > + * (C) Copyright 1995-1996 Gary Thomas (g...@linuxppc.org) > + * > + * Largely rewritten by Cort Dougan (c...@cs.nmt.edu) > + * and Paul Mackerras. > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License as > + * published by the Free Software Foundation; either version 2 of > + * the License, or (at your option) any later version. > + */ > + > +#include <ppc_asm.tmpl> > +#include <ppc_defs.h> > +#include <config.h> > + > +/* > + * Extended precision shifts. > + * > + * Updated to be valid for shift counts from 0 to 63 inclusive. > + * -- Gabriel > + * > + * R3/R4 has 64 bit value > + * R5 has shift count > + * result in R3/R4 > + * > + * ashrdi3: arithmetic right shift (sign propagation) > + * lshrdi3: logical right shift > + * ashldi3: left shift > + */ > + .globl __lshrdi3 > +__lshrdi3: > + subfic r6,r5,32 > + srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count > + addi r7,r5,32 # could be xori, or addi with -32 > + slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count) > + srw r7,r3,r7 # t2 = count < 32 ? 0 : MSW >> (count-32) > + or r4,r4,r6 # LSW |= t1 > + srw r3,r3,r5 # MSW = MSW >> count > + or r4,r4,r7 # LSW |= t2 > + blr > -- > 1.7.2.5 > _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
