18c2ecf20Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0 28c2ecf20Sopenharmony_ci// Copyright (C) 2005-2017 Andes Technology Corporation 38c2ecf20Sopenharmony_ci 48c2ecf20Sopenharmony_ci#include <linux/linkage.h> 58c2ecf20Sopenharmony_ci 68c2ecf20Sopenharmony_ci .text 78c2ecf20Sopenharmony_ciENTRY(memset) 88c2ecf20Sopenharmony_ci move $r5, $r0 ! Return value 98c2ecf20Sopenharmony_ci beqz $r2, end_memset ! Exit when len = 0 108c2ecf20Sopenharmony_ci srli $p1, $r2, 2 ! $p1 is how many words to copy 118c2ecf20Sopenharmony_ci andi $r2, $r2, 3 ! How many bytes are less than a word 128c2ecf20Sopenharmony_ci beqz $p1, byte_set ! When n is less than a word 138c2ecf20Sopenharmony_ci 148c2ecf20Sopenharmony_ci ! set $r1 from ??????ab to abababab 158c2ecf20Sopenharmony_ci andi $r1, $r1, #0x00ff ! $r1 = 000000ab 168c2ecf20Sopenharmony_ci slli $p0, $r1, #8 ! $p0 = 0000ab00 178c2ecf20Sopenharmony_ci or $r1, $r1, $p0 ! $r1 = 0000abab 188c2ecf20Sopenharmony_ci slli $p0, $r1, #16 ! $p0 = abab0000 198c2ecf20Sopenharmony_ci or $r1, $r1, $p0 ! $r1 = abababab 208c2ecf20Sopenharmony_ciword_set: 218c2ecf20Sopenharmony_ci addi $p1, $p1, #-1 ! How many words left to copy 228c2ecf20Sopenharmony_ci smw.bim $r1, [$r0], $r1 ! Copy the word to det 238c2ecf20Sopenharmony_ci bnez $p1, word_set ! Still words to set, continue looping 248c2ecf20Sopenharmony_ci beqz $r2, end_memset ! No left byte to set 258c2ecf20Sopenharmony_cibyte_set: ! Less than 4 bytes left to set 268c2ecf20Sopenharmony_ci addi $r2, $r2, #-1 ! Decrease len by 1 278c2ecf20Sopenharmony_ci sbi.bi $r1, [$r0], #1 ! Set data of the next byte to $r1 288c2ecf20Sopenharmony_ci bnez $r2, byte_set ! Still bytes left to set 298c2ecf20Sopenharmony_ciend_memset: 308c2ecf20Sopenharmony_ci move $r0, $r5 318c2ecf20Sopenharmony_ci ret 328c2ecf20Sopenharmony_ci 338c2ecf20Sopenharmony_ciENDPROC(memset) 34