LXR linux/arch/arm64/lib/clear

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 * Copyright (C) 2012 ARM Ltd.
   4 */
   5
   6#include <linux/linkage.h>
   7#include <linux/const.h>
   8#include <asm/assembler.h>
   9#include <asm/page.h>
  10
  11/*
  12 * Clear page @dest
  13 *
  14 * Parameters:
  15 *      x0 - dest
  16 */
  17SYM_FUNC_START_PI(clear_page)
  18        mrs     x1, dczid_el0
  19        and     w1, w1, #0xf
  20        mov     x2, #4
  21        lsl     x1, x2, x1
  22
  231:      dc      zva, x0
  24        add     x0, x0, x1
  25        tst     x0, #(PAGE_SIZE - 1)
  26        b.ne    1b
  27        ret
  28SYM_FUNC_END_PI(clear_page)
  29EXPORT_SYMBOL(clear_page)
  30