linux_dsm_epyc7002/arch/mips/loongson64/Platform
Huacai Chen 5188129b8c MIPS: Loongson-3: Improve -march option and move it to Platform
If GCC >= 4.9 and Binutils >=2.25, we use -march=loongson3a, otherwise
we use -march=mips64r2, this can slightly improve performance. Besides,
arch/mips/loongson64/Platform is a better location rather than arch/
mips/Makefile.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12161/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-01-22 01:59:18 +01:00

55 lines
2.1 KiB
Plaintext

#
# Loongson Processors' Support
#
# Only gcc >= 4.4 have Loongson specific support
cflags-$(CONFIG_CPU_LOONGSON2) += -Wa,--trap
cflags-$(CONFIG_CPU_LOONGSON2E) += \
$(call cc-option,-march=loongson2e,-march=r4600)
cflags-$(CONFIG_CPU_LOONGSON2F) += \
$(call cc-option,-march=loongson2f,-march=r4600)
# Enable the workarounds for Loongson2f
ifdef CONFIG_CPU_LOONGSON2F_WORKAROUNDS
ifeq ($(call as-option,-Wa$(comma)-mfix-loongson2f-nop,),)
$(error only binutils >= 2.20.2 have needed option -mfix-loongson2f-nop)
else
cflags-$(CONFIG_CPU_NOP_WORKAROUNDS) += -Wa$(comma)-mfix-loongson2f-nop
endif
ifeq ($(call as-option,-Wa$(comma)-mfix-loongson2f-jump,),)
$(error only binutils >= 2.20.2 have needed option -mfix-loongson2f-jump)
else
cflags-$(CONFIG_CPU_JUMP_WORKAROUNDS) += -Wa$(comma)-mfix-loongson2f-jump
endif
endif
cflags-$(CONFIG_CPU_LOONGSON3) += -Wa,--trap
#
# binutils from v2.25 on and gcc starting from v4.9.0 treat -march=loongson3a
# as MIPS64 R2; older versions as just R1. This leaves the possibility open
# that GCC might generate R2 code for -march=loongson3a which then is rejected
# by GAS. The cc-option can't probe for this behaviour so -march=loongson3a
# can't easily be used safely within the kbuild framework.
#
ifeq ($(call cc-ifversion, -ge, 0409, y), y)
ifeq ($(call ld-ifversion, -ge, 22500000, y), y)
cflags-$(CONFIG_CPU_LOONGSON3) += \
$(call cc-option,-march=loongson3a -U_MIPS_ISA -D_MIPS_ISA=_MIPS_ISA_MIPS64)
else
cflags-$(CONFIG_CPU_LOONGSON3) += \
$(call cc-option,-march=mips64r2,-mips64r2 -U_MIPS_ISA -D_MIPS_ISA=_MIPS_ISA_MIPS64)
endif
else
cflags-$(CONFIG_CPU_LOONGSON3) += \
$(call cc-option,-march=mips64r2,-mips64r2 -U_MIPS_ISA -D_MIPS_ISA=_MIPS_ISA_MIPS64)
endif
#
# Loongson Machines' Support
#
platform-$(CONFIG_MACH_LOONGSON64) += loongson64/
cflags-$(CONFIG_MACH_LOONGSON64) += -I$(srctree)/arch/mips/include/asm/mach-loongson64 -mno-branch-likely
load-$(CONFIG_LEMOTE_FULOONG2E) += 0xffffffff80100000
load-$(CONFIG_LEMOTE_MACH2F) += 0xffffffff80200000
load-$(CONFIG_LOONGSON_MACH3X) += 0xffffffff80200000