1/* 2 * Copyright (C) 2012 ARM Ltd. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program. If not, see <http://www.gnu.org/licenses/>. 15 */ 16 17#include <linux/linkage.h> 18#include <linux/const.h> 19#include <asm/assembler.h> 20#include <asm/page.h> 21#include <asm/cpufeature.h> 22#include <asm/alternative.h> 23 24/* 25 * Copy a page from src to dest (both are page aligned) 26 * 27 * Parameters: 28 * x0 - dest 29 * x1 - src 30 */ 31ENTRY(copy_page) 32alternative_if_not ARM64_HAS_NO_HW_PREFETCH 33 nop 34 nop 35alternative_else 36 # Prefetch two cache lines ahead. 37 prfm pldl1strm, [x1, #128] 38 prfm pldl1strm, [x1, #256] 39alternative_endif 40 41 ldp x2, x3, [x1] 42 ldp x4, x5, [x1, #16] 43 ldp x6, x7, [x1, #32] 44 ldp x8, x9, [x1, #48] 45 ldp x10, x11, [x1, #64] 46 ldp x12, x13, [x1, #80] 47 ldp x14, x15, [x1, #96] 48 ldp x16, x17, [x1, #112] 49 50 mov x18, #(PAGE_SIZE - 128) 51 add x1, x1, #128 521: 53 subs x18, x18, #128 54 55alternative_if_not ARM64_HAS_NO_HW_PREFETCH 56 nop 57alternative_else 58 prfm pldl1strm, [x1, #384] 59alternative_endif 60 61 stnp x2, x3, [x0] 62 ldp x2, x3, [x1] 63 stnp x4, x5, [x0, #16] 64 ldp x4, x5, [x1, #16] 65 stnp x6, x7, [x0, #32] 66 ldp x6, x7, [x1, #32] 67 stnp x8, x9, [x0, #48] 68 ldp x8, x9, [x1, #48] 69 stnp x10, x11, [x0, #64] 70 ldp x10, x11, [x1, #64] 71 stnp x12, x13, [x0, #80] 72 ldp x12, x13, [x1, #80] 73 stnp x14, x15, [x0, #96] 74 ldp x14, x15, [x1, #96] 75 stnp x16, x17, [x0, #112] 76 ldp x16, x17, [x1, #112] 77 78 add x0, x0, #128 79 add x1, x1, #128 80 81 b.gt 1b 82 83 stnp x2, x3, [x0] 84 stnp x4, x5, [x0, #16] 85 stnp x6, x7, [x0, #32] 86 stnp x8, x9, [x0, #48] 87 stnp x10, x11, [x0, #64] 88 stnp x12, x13, [x0, #80] 89 stnp x14, x15, [x0, #96] 90 stnp x16, x17, [x0, #112] 91 92 ret 93ENDPROC(copy_page) 94