41 lines
724 B
ArmAsm
41 lines
724 B
ArmAsm
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/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Copyright (C) 2012 ARM Ltd.
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*/
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#include <linux/linkage.h>
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#include <linux/const.h>
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#include <asm/assembler.h>
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#include <asm/page.h>
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/*
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* Clear page @dest
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*
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* Parameters:
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* x0 - dest
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*/
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SYM_FUNC_START(__pi_clear_page)
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mrs x1, dczid_el0
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tbnz x1, #4, 2f /* Branch if DC ZVA is prohibited */
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and w1, w1, #0xf
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mov x2, #4
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lsl x1, x2, x1
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1: dc zva, x0
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add x0, x0, x1
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tst x0, #(PAGE_SIZE - 1)
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b.ne 1b
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ret
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2: stnp xzr, xzr, [x0]
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stnp xzr, xzr, [x0, #16]
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stnp xzr, xzr, [x0, #32]
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stnp xzr, xzr, [x0, #48]
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add x0, x0, #64
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tst x0, #(PAGE_SIZE - 1)
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b.ne 2b
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ret
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SYM_FUNC_END(__pi_clear_page)
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SYM_FUNC_ALIAS(clear_page, __pi_clear_page)
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EXPORT_SYMBOL(clear_page)
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