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>
This commit is contained in:
Manuel Lauss 2014-11-07 14:13:54 +01:00 committed by Ralf Baechle
parent 491a48aa52
commit 842dfc11ea
14 changed files with 118 additions and 17 deletions

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@ -93,6 +93,15 @@ LDFLAGS_vmlinux += -G 0 -static -n -nostdlib
KBUILD_AFLAGS_MODULE += -mlong-calls
KBUILD_CFLAGS_MODULE += -mlong-calls
#
# pass -msoft-float to GAS if it supports it. However on newer binutils
# (specifically newer than 2.24.51.20140728) we then also need to explicitly
# set ".set hardfloat" in all files which manipulate floating point registers.
#
ifneq ($(call as-option,-Wa$(comma)-msoft-float,),)
cflags-y += -DGAS_HAS_SET_HARDFLOAT -Wa,-msoft-float
endif
cflags-y += -ffreestanding
#

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@ -13,6 +13,8 @@
#include <asm/mipsregs.h>
.macro fpu_save_single thread tmp=t0
.set push
SET_HARDFLOAT
cfc1 \tmp, fcr31
swc1 $f0, THREAD_FPR0_LS64(\thread)
swc1 $f1, THREAD_FPR1_LS64(\thread)
@ -47,9 +49,12 @@
swc1 $f30, THREAD_FPR30_LS64(\thread)
swc1 $f31, THREAD_FPR31_LS64(\thread)
sw \tmp, THREAD_FCR31(\thread)
.set pop
.endm
.macro fpu_restore_single thread tmp=t0
.set push
SET_HARDFLOAT
lw \tmp, THREAD_FCR31(\thread)
lwc1 $f0, THREAD_FPR0_LS64(\thread)
lwc1 $f1, THREAD_FPR1_LS64(\thread)
@ -84,6 +89,7 @@
lwc1 $f30, THREAD_FPR30_LS64(\thread)
lwc1 $f31, THREAD_FPR31_LS64(\thread)
ctc1 \tmp, fcr31
.set pop
.endm
.macro cpu_save_nonscratch thread

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@ -57,6 +57,8 @@
#endif /* CONFIG_CPU_MIPSR2 */
.macro fpu_save_16even thread tmp=t0
.set push
SET_HARDFLOAT
cfc1 \tmp, fcr31
sdc1 $f0, THREAD_FPR0_LS64(\thread)
sdc1 $f2, THREAD_FPR2_LS64(\thread)
@ -75,11 +77,13 @@
sdc1 $f28, THREAD_FPR28_LS64(\thread)
sdc1 $f30, THREAD_FPR30_LS64(\thread)
sw \tmp, THREAD_FCR31(\thread)
.set pop
.endm
.macro fpu_save_16odd thread
.set push
.set mips64r2
SET_HARDFLOAT
sdc1 $f1, THREAD_FPR1_LS64(\thread)
sdc1 $f3, THREAD_FPR3_LS64(\thread)
sdc1 $f5, THREAD_FPR5_LS64(\thread)
@ -110,6 +114,8 @@
.endm
.macro fpu_restore_16even thread tmp=t0
.set push
SET_HARDFLOAT
lw \tmp, THREAD_FCR31(\thread)
ldc1 $f0, THREAD_FPR0_LS64(\thread)
ldc1 $f2, THREAD_FPR2_LS64(\thread)
@ -133,6 +139,7 @@
.macro fpu_restore_16odd thread
.set push
.set mips64r2
SET_HARDFLOAT
ldc1 $f1, THREAD_FPR1_LS64(\thread)
ldc1 $f3, THREAD_FPR3_LS64(\thread)
ldc1 $f5, THREAD_FPR5_LS64(\thread)
@ -277,6 +284,7 @@
.macro cfcmsa rd, cs
.set push
.set noat
SET_HARDFLOAT
.insn
.word CFC_MSA_INSN | (\cs << 11)
move \rd, $1
@ -286,6 +294,7 @@
.macro ctcmsa cd, rs
.set push
.set noat
SET_HARDFLOAT
move $1, \rs
.word CTC_MSA_INSN | (\cd << 6)
.set pop
@ -294,6 +303,7 @@
.macro ld_d wd, off, base
.set push
.set noat
SET_HARDFLOAT
add $1, \base, \off
.word LDD_MSA_INSN | (\wd << 6)
.set pop
@ -302,6 +312,7 @@
.macro st_d wd, off, base
.set push
.set noat
SET_HARDFLOAT
add $1, \base, \off
.word STD_MSA_INSN | (\wd << 6)
.set pop
@ -310,6 +321,7 @@
.macro copy_u_w rd, ws, n
.set push
.set noat
SET_HARDFLOAT
.insn
.word COPY_UW_MSA_INSN | (\n << 16) | (\ws << 11)
/* move triggers an assembler bug... */
@ -320,6 +332,7 @@
.macro copy_u_d rd, ws, n
.set push
.set noat
SET_HARDFLOAT
.insn
.word COPY_UD_MSA_INSN | (\n << 16) | (\ws << 11)
/* move triggers an assembler bug... */
@ -330,6 +343,7 @@
.macro insert_w wd, n, rs
.set push
.set noat
SET_HARDFLOAT
/* move triggers an assembler bug... */
or $1, \rs, zero
.word INSERT_W_MSA_INSN | (\n << 16) | (\wd << 6)
@ -339,6 +353,7 @@
.macro insert_d wd, n, rs
.set push
.set noat
SET_HARDFLOAT
/* move triggers an assembler bug... */
or $1, \rs, zero
.word INSERT_D_MSA_INSN | (\n << 16) | (\wd << 6)
@ -381,6 +396,7 @@
st_d 31, THREAD_FPR31, \thread
.set push
.set noat
SET_HARDFLOAT
cfcmsa $1, MSA_CSR
sw $1, THREAD_MSA_CSR(\thread)
.set pop
@ -389,6 +405,7 @@
.macro msa_restore_all thread
.set push
.set noat
SET_HARDFLOAT
lw $1, THREAD_MSA_CSR(\thread)
ctcmsa MSA_CSR, $1
.set pop
@ -441,6 +458,7 @@
.macro msa_init_all_upper
.set push
.set noat
SET_HARDFLOAT
not $1, zero
msa_init_upper 0
.set pop

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@ -14,6 +14,20 @@
#include <asm/sgidefs.h>
/*
* starting with binutils 2.24.51.20140729, MIPS binutils warn about mixing
* hardfloat and softfloat object files. The kernel build uses soft-float by
* default, so we also need to pass -msoft-float along to GAS if it supports it.
* But this in turn causes assembler errors in files which access hardfloat
* registers. We detect if GAS supports "-msoft-float" in the Makefile and
* explicitly put ".set hardfloat" where floating point registers are touched.
*/
#ifdef GAS_HAS_SET_HARDFLOAT
#define SET_HARDFLOAT .set hardfloat
#else
#define SET_HARDFLOAT
#endif
#if _MIPS_SIM == _MIPS_SIM_ABI32
/*

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@ -145,8 +145,8 @@ static inline void lose_fpu(int save)
if (is_msa_enabled()) {
if (save) {
save_msa(current);
asm volatile("cfc1 %0, $31"
: "=r"(current->thread.fpu.fcr31));
current->thread.fpu.fcr31 =
read_32bit_cp1_register(CP1_STATUS);
}
disable_msa();
clear_thread_flag(TIF_USEDMSA);

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@ -1324,7 +1324,7 @@ do { \
/*
* Macros to access the floating point coprocessor control registers
*/
#define read_32bit_cp1_register(source) \
#define _read_32bit_cp1_register(source, gas_hardfloat) \
({ \
int __res; \
\
@ -1334,12 +1334,21 @@ do { \
" # gas fails to assemble cfc1 for some archs, \n" \
" # like Octeon. \n" \
" .set mips1 \n" \
" "STR(gas_hardfloat)" \n" \
" cfc1 %0,"STR(source)" \n" \
" .set pop \n" \
: "=r" (__res)); \
__res; \
})
#ifdef GAS_HAS_SET_HARDFLOAT
#define read_32bit_cp1_register(source) \
_read_32bit_cp1_register(source, .set hardfloat)
#else
#define read_32bit_cp1_register(source) \
_read_32bit_cp1_register(source, )
#endif
#ifdef HAVE_AS_DSP
#define rddsp(mask) \
({ \

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@ -144,7 +144,7 @@ int __mm_isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn,
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 @@ int __compute_return_epc_for_insn(struct pt_regs *regs,
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();

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@ -358,6 +358,7 @@ NESTED(nmi_handler, PT_SIZE, sp)
.set push
/* gas fails to assemble cfc1 for some archs (octeon).*/ \
.set mips1
SET_HARDFLOAT
cfc1 a1, fcr31
li a2, ~(0x3f << 12)
and a2, a1

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@ -28,6 +28,8 @@
.set mips1
/* Save floating point context */
LEAF(_save_fp_context)
.set push
SET_HARDFLOAT
li v0, 0 # assume success
cfc1 t1,fcr31
EX(swc1 $f0,(SC_FPREGS+0)(a0))
@ -65,6 +67,7 @@ LEAF(_save_fp_context)
EX(sw t1,(SC_FPC_CSR)(a0))
cfc1 t0,$0 # implementation/version
jr ra
.set pop
.set nomacro
EX(sw t0,(SC_FPC_EIR)(a0))
.set macro
@ -80,6 +83,8 @@ LEAF(_save_fp_context)
* stack frame which might have been changed by the user.
*/
LEAF(_restore_fp_context)
.set push
SET_HARDFLOAT
li v0, 0 # assume success
EX(lw t0,(SC_FPC_CSR)(a0))
EX(lwc1 $f0,(SC_FPREGS+0)(a0))
@ -116,6 +121,7 @@ LEAF(_restore_fp_context)
EX(lwc1 $f31,(SC_FPREGS+248)(a0))
jr ra
ctc1 t0,fcr31
.set pop
END(_restore_fp_context)
.set reorder

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@ -120,6 +120,9 @@ LEAF(_restore_fp)
#define FPU_DEFAULT 0x00000000
.set push
SET_HARDFLOAT
LEAF(_init_fpu)
mfc0 t0, CP0_STATUS
li t1, ST0_CU1
@ -165,3 +168,5 @@ LEAF(_init_fpu)
mtc1 t0, $f31
jr ra
END(_init_fpu)
.set pop

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@ -19,8 +19,12 @@
#include <asm/asm-offsets.h>
#include <asm/regdef.h>
/* preprocessor replaces the fp in ".set fp=64" with $30 otherwise */
#undef fp
.macro EX insn, reg, src
.set push
SET_HARDFLOAT
.set nomacro
.ex\@: \insn \reg, \src
.set pop
@ -33,12 +37,17 @@
.set arch=r4000
LEAF(_save_fp_context)
.set push
SET_HARDFLOAT
cfc1 t1, fcr31
.set pop
#if defined(CONFIG_64BIT) || defined(CONFIG_CPU_MIPS32_R2)
.set push
SET_HARDFLOAT
#ifdef CONFIG_CPU_MIPS32_R2
.set mips64r2
.set mips32r2
.set fp=64
mfc0 t0, CP0_STATUS
sll t0, t0, 5
bgez t0, 1f # skip storing odd if FR=0
@ -64,6 +73,8 @@ LEAF(_save_fp_context)
1: .set pop
#endif
.set push
SET_HARDFLOAT
/* Store the 16 even double precision registers */
EX sdc1 $f0, SC_FPREGS+0(a0)
EX sdc1 $f2, SC_FPREGS+16(a0)
@ -84,11 +95,14 @@ LEAF(_save_fp_context)
EX sw t1, SC_FPC_CSR(a0)
jr ra
li v0, 0 # success
.set pop
END(_save_fp_context)
#ifdef CONFIG_MIPS32_COMPAT
/* Save 32-bit process floating point context */
LEAF(_save_fp_context32)
.set push
SET_HARDFLOAT
cfc1 t1, fcr31
mfc0 t0, CP0_STATUS
@ -134,6 +148,7 @@ LEAF(_save_fp_context32)
EX sw t1, SC32_FPC_CSR(a0)
cfc1 t0, $0 # implementation/version
EX sw t0, SC32_FPC_EIR(a0)
.set pop
jr ra
li v0, 0 # success
@ -150,8 +165,10 @@ LEAF(_restore_fp_context)
#if defined(CONFIG_64BIT) || defined(CONFIG_CPU_MIPS32_R2)
.set push
SET_HARDFLOAT
#ifdef CONFIG_CPU_MIPS32_R2
.set mips64r2
.set mips32r2
.set fp=64
mfc0 t0, CP0_STATUS
sll t0, t0, 5
bgez t0, 1f # skip loading odd if FR=0
@ -175,6 +192,8 @@ LEAF(_restore_fp_context)
EX ldc1 $f31, SC_FPREGS+248(a0)
1: .set pop
#endif
.set push
SET_HARDFLOAT
EX ldc1 $f0, SC_FPREGS+0(a0)
EX ldc1 $f2, SC_FPREGS+16(a0)
EX ldc1 $f4, SC_FPREGS+32(a0)
@ -192,6 +211,7 @@ LEAF(_restore_fp_context)
EX ldc1 $f28, SC_FPREGS+224(a0)
EX ldc1 $f30, SC_FPREGS+240(a0)
ctc1 t1, fcr31
.set pop
jr ra
li v0, 0 # success
END(_restore_fp_context)
@ -199,6 +219,8 @@ LEAF(_restore_fp_context)
#ifdef CONFIG_MIPS32_COMPAT
LEAF(_restore_fp_context32)
/* Restore an o32 sigcontext. */
.set push
SET_HARDFLOAT
EX lw t1, SC32_FPC_CSR(a0)
mfc0 t0, CP0_STATUS
@ -242,6 +264,7 @@ LEAF(_restore_fp_context32)
ctc1 t1, fcr31
jr ra
li v0, 0 # success
.set pop
END(_restore_fp_context32)
#endif

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@ -22,6 +22,9 @@
#include <asm/asmmacro.h>
/* preprocessor replaces the fp in ".set fp=64" with $30 otherwise */
#undef fp
/*
* Offset to the current process status flags, the first 32 bytes of the
* stack are not used.
@ -65,8 +68,12 @@
bgtz a3, 1f
/* Save 128b MSA vector context + scalar FP control & status. */
.set push
SET_HARDFLOAT
cfc1 t1, fcr31
msa_save_all a0
.set pop /* SET_HARDFLOAT */
sw t1, THREAD_FCR31(a0)
b 2f
@ -161,6 +168,9 @@ LEAF(_init_msa_upper)
#define FPU_DEFAULT 0x00000000
.set push
SET_HARDFLOAT
LEAF(_init_fpu)
mfc0 t0, CP0_STATUS
li t1, ST0_CU1
@ -232,7 +242,8 @@ LEAF(_init_fpu)
#ifdef CONFIG_CPU_MIPS32_R2
.set push
.set mips64r2
.set mips32r2
.set fp=64
sll t0, t0, 5 # is Status.FR set?
bgez t0, 1f # no: skip setting upper 32b
@ -291,3 +302,5 @@ LEAF(_init_fpu)
#endif
jr ra
END(_init_fpu)
.set pop /* SET_HARDFLOAT */

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@ -18,6 +18,9 @@
.set noreorder
.set mips2
.set push
SET_HARDFLOAT
/* Save floating point context */
LEAF(_save_fp_context)
mfc0 t0,CP0_STATUS
@ -85,3 +88,5 @@
1: jr ra
nop
END(_restore_fp_context)
.set pop /* SET_HARDFLOAT */

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@ -584,11 +584,7 @@ static int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn,
if (insn.i_format.rs == bc_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();