69 строки
1.6 KiB
ArmAsm
69 строки
1.6 KiB
ArmAsm
/*
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* Based on arch/arm/lib/bitops.h
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*
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* Copyright (C) 2013 ARM Ltd.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <linux/linkage.h>
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#include <asm/assembler.h>
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/*
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* x0: bits 5:0 bit offset
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* bits 31:6 word offset
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* x1: address
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*/
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.macro bitop, name, instr
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ENTRY( \name )
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and w3, w0, #63 // Get bit offset
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eor w0, w0, w3 // Clear low bits
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mov x2, #1
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add x1, x1, x0, lsr #3 // Get word offset
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lsl x3, x2, x3 // Create mask
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1: ldxr x2, [x1]
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\instr x2, x2, x3
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stxr w0, x2, [x1]
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cbnz w0, 1b
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ret
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ENDPROC(\name )
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.endm
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.macro testop, name, instr
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ENTRY( \name )
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and w3, w0, #63 // Get bit offset
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eor w0, w0, w3 // Clear low bits
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mov x2, #1
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add x1, x1, x0, lsr #3 // Get word offset
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lsl x4, x2, x3 // Create mask
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1: ldaxr x2, [x1]
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lsr x0, x2, x3 // Save old value of bit
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\instr x2, x2, x4 // toggle bit
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stlxr w5, x2, [x1]
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cbnz w5, 1b
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and x0, x0, #1
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3: ret
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ENDPROC(\name )
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.endm
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/*
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* Atomic bit operations.
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*/
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bitop change_bit, eor
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bitop clear_bit, bic
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bitop set_bit, orr
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testop test_and_change_bit, eor
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testop test_and_clear_bit, bic
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testop test_and_set_bit, orr
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