MIPS: Fix build with binutils 2.24.51+
Starting with version 2.24.51.20140728 MIPS binutils complain loudly
about mixing soft-float and hard-float object files, leading to this
build failure since GCC is invoked with "-msoft-float" on MIPS:
{standard input}: Warning: .gnu_attribute 4,3 requires `softfloat'
LD arch/mips/alchemy/common/built-in.o
mipsel-softfloat-linux-gnu-ld: Warning: arch/mips/alchemy/common/built-in.o
uses -msoft-float (set by arch/mips/alchemy/common/prom.o),
arch/mips/alchemy/common/sleeper.o uses -mhard-float
To fix this, we detect if GAS is new enough to support "-msoft-float" command
option, and if it does, we can let GCC pass it to GAS; but then we also need
to sprinkle the files which make use of floating point registers with the
necessary ".set hardfloat" directives.
Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Cc: Linux-MIPS <linux-mips@linux-mips.org>
Cc: Matthew Fortune <Matthew.Fortune@imgtec.com>
Cc: Markos Chandras <Markos.Chandras@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/8355/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/branch.c b/arch/mips/kernel/branch.c
index 7b2df22..4d7d99d 100644
--- a/arch/mips/kernel/branch.c
+++ b/arch/mips/kernel/branch.c
@@ -144,7 +144,7 @@
case mm_bc1t_op:
preempt_disable();
if (is_fpu_owner())
- asm volatile("cfc1\t%0,$31" : "=r" (fcr31));
+ fcr31 = read_32bit_cp1_register(CP1_STATUS);
else
fcr31 = current->thread.fpu.fcr31;
preempt_enable();
@@ -562,11 +562,7 @@
case cop1_op:
preempt_disable();
if (is_fpu_owner())
- asm volatile(
- ".set push\n"
- "\t.set mips1\n"
- "\tcfc1\t%0,$31\n"
- "\t.set pop" : "=r" (fcr31));
+ fcr31 = read_32bit_cp1_register(CP1_STATUS);
else
fcr31 = current->thread.fpu.fcr31;
preempt_enable();
