[PATCH v5 2/4] Loongson-2F: Enable fixups of the latest binutils

[Wu Zhangjin <wuzhangjin@gmail.com>]

From: Wu Zhangjin <wuzhangjin@gmail.com>

Changes from old revision:
  o Clear the errror information as suggesttion from Zhang Le.

  o Incorporated with the feedbacks from Ralf and used the options
  introduced from "Loongson: Add CPU_LOONGSON2F_WORKAROUNDS".

As the "Fixups of Loongson2F" patch[1] to binutils have been applied
into binutils 2.20.1. It's time to enable the options provided by the
patch to compile the kernel.

Without these fixups, the system will hang unexpectedly for the bug of
processor.

To learn more about these fixups, please refer to the following
references.

[1] "Fixups of Loongson2F" patch for binutils(actually for gas)
http://sourceware.org/ml/binutils/2009-11/msg00387.html
[2] Chapter 15 of "Loongson2F User Manual"(Chinese Version)
http://www.loongson.cn/uploadfile/file/200808211
[3] English Version of the above chapter 15
http://groups.google.com.hk/group/loongson-dev/msg/e0d2e220958f10a6?dmode=source

Signed-off-by: Zhang Le <r0bertz@gentoo.org>
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
---
 arch/mips/Makefile |   13 +++++++++++++
 1 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/arch/mips/Makefile b/arch/mips/Makefile
index 2f2eac2..0b9c01a 100644
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -136,6 +136,19 @@ 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_MIPS32_R1)	+= $(call cc-option,-march=mips32,-mips32 -U_MIPS_ISA -D_MIPS_ISA=_MIPS_ISA_MIPS32) \
 			-Wa,-mips32 -Wa,--trap
-- 
1.7.0.1