 842dfc11ea
			
		
	
	
	842dfc11ea
	
	
	
		
			
			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>
		
	
			
		
			
				
	
	
		
			172 lines
		
	
	
	
		
			3.3 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			172 lines
		
	
	
	
		
			3.3 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| /*
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|  * r2300_switch.S: R2300 specific task switching code.
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|  *
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|  * Copyright (C) 1994, 1995, 1996, 1999 by Ralf Baechle
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|  * Copyright (C) 1994, 1995, 1996 by Andreas Busse
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|  *
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|  * Multi-cpu abstraction and macros for easier reading:
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|  * Copyright (C) 1996 David S. Miller (davem@davemloft.net)
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|  *
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|  * Further modifications to make this work:
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|  * Copyright (c) 1998-2000 Harald Koerfgen
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|  */
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| #include <asm/asm.h>
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| #include <asm/cachectl.h>
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| #include <asm/fpregdef.h>
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| #include <asm/mipsregs.h>
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| #include <asm/asm-offsets.h>
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| #include <asm/regdef.h>
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| #include <asm/stackframe.h>
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| #include <asm/thread_info.h>
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| 
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| #include <asm/asmmacro.h>
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| 
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| 	.set	mips1
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| 	.align	5
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| 
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| /*
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|  * Offset to the current process status flags, the first 32 bytes of the
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|  * stack are not used.
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|  */
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| #define ST_OFF (_THREAD_SIZE - 32 - PT_SIZE + PT_STATUS)
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| 
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| /*
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|  * FPU context is saved iff the process has used it's FPU in the current
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|  * time slice as indicated by TIF_USEDFPU.  In any case, the CU1 bit for user
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|  * space STATUS register should be 0, so that a process *always* starts its
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|  * userland with FPU disabled after each context switch.
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|  *
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|  * FPU will be enabled as soon as the process accesses FPU again, through
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|  * do_cpu() trap.
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|  */
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| 
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| /*
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|  * task_struct *resume(task_struct *prev, task_struct *next,
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|  *		       struct thread_info *next_ti, int usedfpu)
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|  */
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| LEAF(resume)
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| 	mfc0	t1, CP0_STATUS
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| 	sw	t1, THREAD_STATUS(a0)
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| 	cpu_save_nonscratch a0
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| 	sw	ra, THREAD_REG31(a0)
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| 
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| 	beqz	a3, 1f
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| 
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| 	PTR_L	t3, TASK_THREAD_INFO(a0)
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| 
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| 	/*
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| 	 * clear saved user stack CU1 bit
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| 	 */
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| 	lw	t0, ST_OFF(t3)
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| 	li	t1, ~ST0_CU1
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| 	and	t0, t0, t1
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| 	sw	t0, ST_OFF(t3)
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| 
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| 	fpu_save_single a0, t0			# clobbers t0
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| 
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| 1:
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| 
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| #if defined(CONFIG_CC_STACKPROTECTOR) && !defined(CONFIG_SMP)
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| 	PTR_LA	t8, __stack_chk_guard
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| 	LONG_L	t9, TASK_STACK_CANARY(a1)
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| 	LONG_S	t9, 0(t8)
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| #endif
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| 
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| 	/*
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| 	 * The order of restoring the registers takes care of the race
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| 	 * updating $28, $29 and kernelsp without disabling ints.
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| 	 */
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| 	move	$28, a2
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| 	cpu_restore_nonscratch a1
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| 
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| 	addiu	t1, $28, _THREAD_SIZE - 32
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| 	sw	t1, kernelsp
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| 
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| 	mfc0	t1, CP0_STATUS		/* Do we really need this? */
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| 	li	a3, 0xff01
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| 	and	t1, a3
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| 	lw	a2, THREAD_STATUS(a1)
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| 	nor	a3, $0, a3
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| 	and	a2, a3
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| 	or	a2, t1
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| 	mtc0	a2, CP0_STATUS
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| 	move	v0, a0
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| 	jr	ra
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| 	END(resume)
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| 
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| /*
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|  * Save a thread's fp context.
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|  */
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| LEAF(_save_fp)
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| 	fpu_save_single a0, t1			# clobbers t1
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| 	jr	ra
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| 	END(_save_fp)
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| 
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| /*
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|  * Restore a thread's fp context.
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|  */
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| LEAF(_restore_fp)
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| 	fpu_restore_single a0, t1		# clobbers t1
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| 	jr	ra
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| 	END(_restore_fp)
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| 
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| /*
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|  * Load the FPU with signalling NANS.  This bit pattern we're using has
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|  * the property that no matter whether considered as single or as double
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|  * precision represents signaling NANS.
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|  *
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|  * We initialize fcr31 to rounding to nearest, no exceptions.
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|  */
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| 
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| #define FPU_DEFAULT  0x00000000
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| 
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| 	.set push
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| 	SET_HARDFLOAT
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| 
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| LEAF(_init_fpu)
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| 	mfc0	t0, CP0_STATUS
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| 	li	t1, ST0_CU1
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| 	or	t0, t1
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| 	mtc0	t0, CP0_STATUS
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| 
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| 	li	t1, FPU_DEFAULT
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| 	ctc1	t1, fcr31
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| 
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| 	li	t0, -1
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| 
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| 	mtc1	t0, $f0
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| 	mtc1	t0, $f1
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| 	mtc1	t0, $f2
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| 	mtc1	t0, $f3
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| 	mtc1	t0, $f4
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| 	mtc1	t0, $f5
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| 	mtc1	t0, $f6
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| 	mtc1	t0, $f7
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| 	mtc1	t0, $f8
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| 	mtc1	t0, $f9
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| 	mtc1	t0, $f10
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| 	mtc1	t0, $f11
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| 	mtc1	t0, $f12
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| 	mtc1	t0, $f13
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| 	mtc1	t0, $f14
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| 	mtc1	t0, $f15
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| 	mtc1	t0, $f16
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| 	mtc1	t0, $f17
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| 	mtc1	t0, $f18
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| 	mtc1	t0, $f19
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| 	mtc1	t0, $f20
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| 	mtc1	t0, $f21
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| 	mtc1	t0, $f22
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| 	mtc1	t0, $f23
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| 	mtc1	t0, $f24
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| 	mtc1	t0, $f25
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| 	mtc1	t0, $f26
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| 	mtc1	t0, $f27
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| 	mtc1	t0, $f28
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| 	mtc1	t0, $f29
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| 	mtc1	t0, $f30
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| 	mtc1	t0, $f31
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| 	jr	ra
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| 	END(_init_fpu)
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| 
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| 	.set pop
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