Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) // Copyright (C) 2005-2017 Andes Technology Corporation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4) #include <linux/linkage.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) #include <asm/assembler.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) #include <asm/errno.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) /* Prototype: int __arch_clear_user(void *addr, size_t sz)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9)  * Purpose  : clear some user memory
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)  * Params   : addr - user memory address to clear
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)  *          : sz   - number of bytes to clear
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)  * Returns  : number of bytes NOT cleared
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 	.text
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 	.align	5
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) ENTRY(__arch_clear_user)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 	add	$r5, $r0, $r1
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 	beqz	$r1, clear_exit
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 	xor	$p1, $p1, $p1		! Use $p1=0 to clear mem
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 	srli	$p0, $r1, #2		! $p0 = number of word to clear
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	andi	$r1, $r1, #3		! Bytes less than a word to copy
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 	beqz	$p0, byte_clear		! Only less than a word to clear
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) word_clear:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) USER(	smw.bim,$p1, [$r0], $p1)	! Clear the word
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 	addi	$p0, $p0, #-1		! Decrease word count
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 	bnez	$p0, word_clear		! Continue looping to clear all words
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 	beqz	$r1, clear_exit		! No left bytes to copy
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) byte_clear:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) USER(	sbi.bi,	$p1, [$r0], #1)		! Clear the byte
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 	addi	$r1, $r1, #-1		! Decrease byte count
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 	bnez	$r1, byte_clear		! Continue looping to clear all left bytes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) clear_exit:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 	move	$r0, $r1		! Set return value
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 	ret
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 	.section .fixup,"ax"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	.align	0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 9001:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	sub	$r0, $r5, $r0		! Bytes left to copy
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 	ret
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 	.previous
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) ENDPROC(__arch_clear_user)