Commit da3de6df authored by Kumar Gala's avatar Kumar Gala Committed by Paul Mackerras
Browse files

[POWERPC] Fix -Os kernel builds with newer gcc versions 

GCC 4.4.x looks to be adding support for generating out-of-line register
saves/restores based on:

http://gcc.gnu.org/ml/gcc-patches/2008-04/msg01678.html



This breaks the kernel if we enable CONFIG_CC_OPTIMIZE_FOR_SIZE.  To fix
this we add the use the save/restore code from gcc and simplified it down
for our needs (integer only).

Additionally, we have to link this code into each module.  The other
solution was to add EXPORT_SYMBOL() which meant going through the
trampoline which seemed nonsensical for these out-of-line routines.

Finally, we add some checks to prom_init_check.sh to ignore the
out-of-line save/restore functions.

Signed-off-by: default avatarKumar Gala <galak@kernel.crashing.org>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent 143580ec

arch/powerpc/Makefile

+2 −0
Original line number Diff line number Diff line
@@ -96,6 +96,8 @@ endif 
else

	KBUILD_CFLAGS += $(call cc-option,-mtune=power4)

endif

else

LDFLAGS_MODULE	+= arch/powerpc/lib/crtsavres.o

endif



ifeq ($(CONFIG_TUNE_CELL),y)

arch/powerpc/kernel/prom_init_check.sh

+14 −0
Original line number Diff line number Diff line
@@ -48,6 +48,20 @@ do 
		fi

	done



	# ignore register save/restore funcitons

	if [ "${UNDEF:0:9}" = "_restgpr_" ]; then

		OK=1

	fi

	if [ "${UNDEF:0:11}" = "_rest32gpr_" ]; then

		OK=1

	fi

	if [ "${UNDEF:0:9}" = "_savegpr_" ]; then

		OK=1

	fi

	if [ "${UNDEF:0:11}" = "_save32gpr_" ]; then

		OK=1

	fi



	if [ $OK -eq 0 ]; then

		ERROR=1

		echo "Error: External symbol '$UNDEF' referenced" \

arch/powerpc/lib/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -9,7 +9,7 @@ endif 
ifeq ($(CONFIG_PPC_MERGE),y)

obj-y			:= string.o alloc.o \

			   checksum_$(CONFIG_WORD_SIZE).o

obj-$(CONFIG_PPC32)	+= div64.o copy_32.o

obj-$(CONFIG_PPC32)	+= div64.o copy_32.o crtsavres.o

obj-$(CONFIG_HAS_IOMEM)	+= devres.o

endif

arch/powerpc/lib/crtsavres.S

0 → 100644
+229 −0
Original line number Diff line number Diff line 
/*

 * Special support for eabi and SVR4

 *

 *   Copyright (C) 1995, 1996, 1998, 2000, 2001 Free Software Foundation, Inc.

 *   Copyright 2008 Freescale Semiconductor, Inc.

 *   Written By Michael Meissner

 *

 * Based on gcc/config/rs6000/crtsavres.asm from gcc

 *

 * This file 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, or (at your option) any

 * later version.

 *

 * In addition to the permissions in the GNU General Public License, the

 * Free Software Foundation gives you unlimited permission to link the

 * compiled version of this file with other programs, and to distribute

 * those programs without any restriction coming from the use of this

 * file.  (The General Public License restrictions do apply in other

 * respects; for example, they cover modification of the file, and

 * distribution when not linked into another program.)

 *

 * This file is distributed in the hope that it will be useful, but

 * WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; see the file COPYING.  If not, write to

 * the Free Software Foundation, 51 Franklin Street, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 *

 *    As a special exception, if you link this library with files

 *    compiled with GCC to produce an executable, this does not cause

 *    the resulting executable to be covered by the GNU General Public License.

 *    This exception does not however invalidate any other reasons why

 *    the executable file might be covered by the GNU General Public License.

 */



#include <asm/ppc_asm.h>



	.file	"crtsavres.S"

	.section ".text"



#ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE



/* Routines for saving integer registers, called by the compiler.  */

/* Called with r11 pointing to the stack header word of the caller of the */

/* function, just beyond the end of the integer save area.  */



_GLOBAL(_savegpr_14)

_GLOBAL(_save32gpr_14)

	stw	14,-72(11)	/* save gp registers */

_GLOBAL(_savegpr_15)

_GLOBAL(_save32gpr_15)

	stw	15,-68(11)

_GLOBAL(_savegpr_16)

_GLOBAL(_save32gpr_16)

	stw	16,-64(11)

_GLOBAL(_savegpr_17)

_GLOBAL(_save32gpr_17)

	stw	17,-60(11)

_GLOBAL(_savegpr_18)

_GLOBAL(_save32gpr_18)

	stw	18,-56(11)

_GLOBAL(_savegpr_19)

_GLOBAL(_save32gpr_19)

	stw	19,-52(11)

_GLOBAL(_savegpr_20)

_GLOBAL(_save32gpr_20)

	stw	20,-48(11)

_GLOBAL(_savegpr_21)

_GLOBAL(_save32gpr_21)

	stw	21,-44(11)

_GLOBAL(_savegpr_22)

_GLOBAL(_save32gpr_22)

	stw	22,-40(11)

_GLOBAL(_savegpr_23)

_GLOBAL(_save32gpr_23)

	stw	23,-36(11)

_GLOBAL(_savegpr_24)

_GLOBAL(_save32gpr_24)

	stw	24,-32(11)

_GLOBAL(_savegpr_25)

_GLOBAL(_save32gpr_25)

	stw	25,-28(11)

_GLOBAL(_savegpr_26)

_GLOBAL(_save32gpr_26)

	stw	26,-24(11)

_GLOBAL(_savegpr_27)

_GLOBAL(_save32gpr_27)

	stw	27,-20(11)

_GLOBAL(_savegpr_28)

_GLOBAL(_save32gpr_28)

	stw	28,-16(11)

_GLOBAL(_savegpr_29)

_GLOBAL(_save32gpr_29)

	stw	29,-12(11)

_GLOBAL(_savegpr_30)

_GLOBAL(_save32gpr_30)

	stw	30,-8(11)

_GLOBAL(_savegpr_31)

_GLOBAL(_save32gpr_31)

	stw	31,-4(11)

	blr



/* Routines for restoring integer registers, called by the compiler.  */

/* Called with r11 pointing to the stack header word of the caller of the */

/* function, just beyond the end of the integer restore area.  */



_GLOBAL(_restgpr_14)

_GLOBAL(_rest32gpr_14)

	lwz	14,-72(11)	/* restore gp registers */

_GLOBAL(_restgpr_15)

_GLOBAL(_rest32gpr_15)

	lwz	15,-68(11)

_GLOBAL(_restgpr_16)

_GLOBAL(_rest32gpr_16)

	lwz	16,-64(11)

_GLOBAL(_restgpr_17)

_GLOBAL(_rest32gpr_17)

	lwz	17,-60(11)

_GLOBAL(_restgpr_18)

_GLOBAL(_rest32gpr_18)

	lwz	18,-56(11)

_GLOBAL(_restgpr_19)

_GLOBAL(_rest32gpr_19)

	lwz	19,-52(11)

_GLOBAL(_restgpr_20)

_GLOBAL(_rest32gpr_20)

	lwz	20,-48(11)

_GLOBAL(_restgpr_21)

_GLOBAL(_rest32gpr_21)

	lwz	21,-44(11)

_GLOBAL(_restgpr_22)

_GLOBAL(_rest32gpr_22)

	lwz	22,-40(11)

_GLOBAL(_restgpr_23)

_GLOBAL(_rest32gpr_23)

	lwz	23,-36(11)

_GLOBAL(_restgpr_24)

_GLOBAL(_rest32gpr_24)

	lwz	24,-32(11)

_GLOBAL(_restgpr_25)

_GLOBAL(_rest32gpr_25)

	lwz	25,-28(11)

_GLOBAL(_restgpr_26)

_GLOBAL(_rest32gpr_26)

	lwz	26,-24(11)

_GLOBAL(_restgpr_27)

_GLOBAL(_rest32gpr_27)

	lwz	27,-20(11)

_GLOBAL(_restgpr_28)

_GLOBAL(_rest32gpr_28)

	lwz	28,-16(11)

_GLOBAL(_restgpr_29)

_GLOBAL(_rest32gpr_29)

	lwz	29,-12(11)

_GLOBAL(_restgpr_30)

_GLOBAL(_rest32gpr_30)

	lwz	30,-8(11)

_GLOBAL(_restgpr_31)

_GLOBAL(_rest32gpr_31)

	lwz	31,-4(11)

	blr



/* Routines for restoring integer registers, called by the compiler.  */

/* Called with r11 pointing to the stack header word of the caller of the */

/* function, just beyond the end of the integer restore area.  */



_GLOBAL(_restgpr_14_x)

_GLOBAL(_rest32gpr_14_x)

	lwz	14,-72(11)	/* restore gp registers */

_GLOBAL(_restgpr_15_x)

_GLOBAL(_rest32gpr_15_x)

	lwz	15,-68(11)

_GLOBAL(_restgpr_16_x)

_GLOBAL(_rest32gpr_16_x)

	lwz	16,-64(11)

_GLOBAL(_restgpr_17_x)

_GLOBAL(_rest32gpr_17_x)

	lwz	17,-60(11)

_GLOBAL(_restgpr_18_x)

_GLOBAL(_rest32gpr_18_x)

	lwz	18,-56(11)

_GLOBAL(_restgpr_19_x)

_GLOBAL(_rest32gpr_19_x)

	lwz	19,-52(11)

_GLOBAL(_restgpr_20_x)

_GLOBAL(_rest32gpr_20_x)

	lwz	20,-48(11)

_GLOBAL(_restgpr_21_x)

_GLOBAL(_rest32gpr_21_x)

	lwz	21,-44(11)

_GLOBAL(_restgpr_22_x)

_GLOBAL(_rest32gpr_22_x)

	lwz	22,-40(11)

_GLOBAL(_restgpr_23_x)

_GLOBAL(_rest32gpr_23_x)

	lwz	23,-36(11)

_GLOBAL(_restgpr_24_x)

_GLOBAL(_rest32gpr_24_x)

	lwz	24,-32(11)

_GLOBAL(_restgpr_25_x)

_GLOBAL(_rest32gpr_25_x)

	lwz	25,-28(11)

_GLOBAL(_restgpr_26_x)

_GLOBAL(_rest32gpr_26_x)

	lwz	26,-24(11)

_GLOBAL(_restgpr_27_x)

_GLOBAL(_rest32gpr_27_x)

	lwz	27,-20(11)

_GLOBAL(_restgpr_28_x)

_GLOBAL(_rest32gpr_28_x)

	lwz	28,-16(11)

_GLOBAL(_restgpr_29_x)

_GLOBAL(_rest32gpr_29_x)

	lwz	29,-12(11)

_GLOBAL(_restgpr_30_x)

_GLOBAL(_rest32gpr_30_x)

	lwz	30,-8(11)

_GLOBAL(_restgpr_31_x)

_GLOBAL(_rest32gpr_31_x)

	lwz	0,4(11)

	lwz	31,-4(11)

	mtlr	0

	mr	1,11

	blr

#endif

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