5c7dd7acc3
repo: https://github.com/T-head-Semi/linux commit: b1313fe517ca3703119dcc99ef3bbf75ab42bcfb Change-Id: I6cbb35294024ea3a66140e311f4bb705fd7fd626
47 lines
751 B
ArmAsm
47 lines
751 B
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
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#include <linux/linkage.h>
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#include <asm/export.h>
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.text
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/*
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* Inputs:
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* %esi : memory location to compare
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* %eax : low 32 bits of old value
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* %edx : high 32 bits of old value
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* %ebx : low 32 bits of new value
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* %ecx : high 32 bits of new value
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*/
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SYM_FUNC_START(cmpxchg8b_emu)
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#
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# Emulate 'cmpxchg8b (%esi)' on UP except we don't
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# set the whole ZF thing (caller will just compare
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# eax:edx with the expected value)
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#
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pushfl
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cli
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cmpl (%esi), %eax
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jne .Lnot_same
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cmpl 4(%esi), %edx
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jne .Lhalf_same
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movl %ebx, (%esi)
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movl %ecx, 4(%esi)
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popfl
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ret
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.Lnot_same:
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movl (%esi), %eax
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.Lhalf_same:
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movl 4(%esi), %edx
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popfl
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ret
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SYM_FUNC_END(cmpxchg8b_emu)
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EXPORT_SYMBOL(cmpxchg8b_emu)
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