mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-11-01 17:08:10 +00:00
91 lines
1.4 KiB
ArmAsm
91 lines
1.4 KiB
ArmAsm
|
/* SPDX-License-Identifier: GPL-2.0 */
|
||
|
|
||
|
/*
|
||
|
* String handling functions for PowerPC32
|
||
|
*
|
||
|
* Copyright (C) 1996 Paul Mackerras.
|
||
|
*
|
||
|
*/
|
||
|
|
||
|
#include <asm/ppc_asm.h>
|
||
|
#include <asm/export.h>
|
||
|
#include <asm/cache.h>
|
||
|
|
||
|
.text
|
||
|
|
||
|
CACHELINE_BYTES = L1_CACHE_BYTES
|
||
|
LG_CACHELINE_BYTES = L1_CACHE_SHIFT
|
||
|
CACHELINE_MASK = (L1_CACHE_BYTES-1)
|
||
|
|
||
|
_GLOBAL(__clear_user)
|
||
|
/*
|
||
|
* Use dcbz on the complete cache lines in the destination
|
||
|
* to set them to zero. This requires that the destination
|
||
|
* area is cacheable.
|
||
|
*/
|
||
|
cmplwi cr0, r4, 4
|
||
|
mr r10, r3
|
||
|
li r3, 0
|
||
|
blt 7f
|
||
|
|
||
|
11: stw r3, 0(r10)
|
||
|
beqlr
|
||
|
andi. r0, r10, 3
|
||
|
add r11, r0, r4
|
||
|
subf r6, r0, r10
|
||
|
|
||
|
clrlwi r7, r6, 32 - LG_CACHELINE_BYTES
|
||
|
add r8, r7, r11
|
||
|
srwi r9, r8, LG_CACHELINE_BYTES
|
||
|
addic. r9, r9, -1 /* total number of complete cachelines */
|
||
|
ble 2f
|
||
|
xori r0, r7, CACHELINE_MASK & ~3
|
||
|
srwi. r0, r0, 2
|
||
|
beq 3f
|
||
|
mtctr r0
|
||
|
4: stwu r3, 4(r6)
|
||
|
bdnz 4b
|
||
|
3: mtctr r9
|
||
|
li r7, 4
|
||
|
10: dcbz r7, r6
|
||
|
addi r6, r6, CACHELINE_BYTES
|
||
|
bdnz 10b
|
||
|
clrlwi r11, r8, 32 - LG_CACHELINE_BYTES
|
||
|
addi r11, r11, 4
|
||
|
|
||
|
2: srwi r0 ,r11 ,2
|
||
|
mtctr r0
|
||
|
bdz 6f
|
||
|
1: stwu r3, 4(r6)
|
||
|
bdnz 1b
|
||
|
6: andi. r11, r11, 3
|
||
|
beqlr
|
||
|
mtctr r11
|
||
|
addi r6, r6, 3
|
||
|
8: stbu r3, 1(r6)
|
||
|
bdnz 8b
|
||
|
blr
|
||
|
|
||
|
7: cmpwi cr0, r4, 0
|
||
|
beqlr
|
||
|
mtctr r4
|
||
|
addi r6, r10, -1
|
||
|
9: stbu r3, 1(r6)
|
||
|
bdnz 9b
|
||
|
blr
|
||
|
|
||
|
90: mr r3, r4
|
||
|
blr
|
||
|
91: add r3, r10, r4
|
||
|
subf r3, r6, r3
|
||
|
blr
|
||
|
|
||
|
EX_TABLE(11b, 90b)
|
||
|
EX_TABLE(4b, 91b)
|
||
|
EX_TABLE(10b, 91b)
|
||
|
EX_TABLE(1b, 91b)
|
||
|
EX_TABLE(8b, 91b)
|
||
|
EX_TABLE(9b, 91b)
|
||
|
|
||
|
EXPORT_SYMBOL(__clear_user)
|