1*4882a593Smuzhiyun// SPDX-License-Identifier: GPL-2.0 2*4882a593Smuzhiyun// Copyright (C) 2005-2017 Andes Technology Corporation 3*4882a593Smuzhiyun 4*4882a593Smuzhiyun#include <linux/linkage.h> 5*4882a593Smuzhiyun 6*4882a593Smuzhiyun .text 7*4882a593SmuzhiyunENTRY(memset) 8*4882a593Smuzhiyun move $r5, $r0 ! Return value 9*4882a593Smuzhiyun beqz $r2, end_memset ! Exit when len = 0 10*4882a593Smuzhiyun srli $p1, $r2, 2 ! $p1 is how many words to copy 11*4882a593Smuzhiyun andi $r2, $r2, 3 ! How many bytes are less than a word 12*4882a593Smuzhiyun beqz $p1, byte_set ! When n is less than a word 13*4882a593Smuzhiyun 14*4882a593Smuzhiyun ! set $r1 from ??????ab to abababab 15*4882a593Smuzhiyun andi $r1, $r1, #0x00ff ! $r1 = 000000ab 16*4882a593Smuzhiyun slli $p0, $r1, #8 ! $p0 = 0000ab00 17*4882a593Smuzhiyun or $r1, $r1, $p0 ! $r1 = 0000abab 18*4882a593Smuzhiyun slli $p0, $r1, #16 ! $p0 = abab0000 19*4882a593Smuzhiyun or $r1, $r1, $p0 ! $r1 = abababab 20*4882a593Smuzhiyunword_set: 21*4882a593Smuzhiyun addi $p1, $p1, #-1 ! How many words left to copy 22*4882a593Smuzhiyun smw.bim $r1, [$r0], $r1 ! Copy the word to det 23*4882a593Smuzhiyun bnez $p1, word_set ! Still words to set, continue looping 24*4882a593Smuzhiyun beqz $r2, end_memset ! No left byte to set 25*4882a593Smuzhiyunbyte_set: ! Less than 4 bytes left to set 26*4882a593Smuzhiyun addi $r2, $r2, #-1 ! Decrease len by 1 27*4882a593Smuzhiyun sbi.bi $r1, [$r0], #1 ! Set data of the next byte to $r1 28*4882a593Smuzhiyun bnez $r2, byte_set ! Still bytes left to set 29*4882a593Smuzhiyunend_memset: 30*4882a593Smuzhiyun move $r0, $r5 31*4882a593Smuzhiyun ret 32*4882a593Smuzhiyun 33*4882a593SmuzhiyunENDPROC(memset) 34