68 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			68 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
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#if __LINUX_ARM_ARCH__ >= 6 && defined(CONFIG_CPU_32v6K)
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	.macro	bitop, instr
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	mov	r2, #1
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	and	r3, r0, #7		@ Get bit offset
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	add	r1, r1, r0, lsr #3	@ Get byte offset
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	mov	r3, r2, lsl r3
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1:	ldrexb	r2, [r1]
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	\instr	r2, r2, r3
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	strexb	r0, r2, [r1]
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	cmp	r0, #0
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	bne	1b
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	mov	pc, lr
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	.endm
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	.macro	testop, instr, store
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	and	r3, r0, #7		@ Get bit offset
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	mov	r2, #1
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	add	r1, r1, r0, lsr #3	@ Get byte offset
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	mov	r3, r2, lsl r3		@ create mask
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	smp_dmb
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1:	ldrexb	r2, [r1]
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	ands	r0, r2, r3		@ save old value of bit
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	\instr	r2, r2, r3			@ toggle bit
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	strexb	ip, r2, [r1]
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	cmp	ip, #0
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	bne	1b
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	smp_dmb
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	cmp	r0, #0
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	movne	r0, #1
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2:	mov	pc, lr
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	.endm
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#else
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	.macro	bitop, instr
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	and	r2, r0, #7
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	mov	r3, #1
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	mov	r3, r3, lsl r2
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	save_and_disable_irqs ip
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	ldrb	r2, [r1, r0, lsr #3]
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	\instr	r2, r2, r3
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	strb	r2, [r1, r0, lsr #3]
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	restore_irqs ip
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	mov	pc, lr
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	.endm
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/**
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 * testop - implement a test_and_xxx_bit operation.
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 * @instr: operational instruction
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 * @store: store instruction
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 *
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 * Note: we can trivially conditionalise the store instruction
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 * to avoid dirtying the data cache.
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 */
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	.macro	testop, instr, store
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	add	r1, r1, r0, lsr #3
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	and	r3, r0, #7
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	mov	r0, #1
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	save_and_disable_irqs ip
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	ldrb	r2, [r1]
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	tst	r2, r0, lsl r3
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	\instr	r2, r2, r0, lsl r3
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	\store	r2, [r1]
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	moveq	r0, #0
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	restore_irqs ip
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	mov	pc, lr
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	.endm
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#endif
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