/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
*/
#include <linux/linkage.h>
#include <asm/cache.h>
/*
* The memset implementation below is optimized to use prefetchw and prealloc
* instruction in case of CPU with 64B L1 data cache line (L1_CACHE_SHIFT == 6)
* If you want to implement optimized memset for other possible L1 data cache
* line lengths (32B and 128B) you should rewrite code carefully checking
* we don't call any prefetchw/prealloc instruction for L1 cache lines which
* don't belongs to memset area.
*/
#if L1_CACHE_SHIFT == 6
.macro PREALLOC_INSTR reg, off
prealloc [\reg, \off]
.endm
.macro PREFETCHW_INSTR reg, off
prefetchw [\reg, \off]
.endm
#else
.macro PREALLOC_INSTR reg, off
.endm
.macro PREFETCHW_INSTR reg, off
.endm
#endif
ENTRY_CFI(memset)
PREFETCHW_INSTR r0, 0 ; Prefetch the first write location
mov.f 0, r2
;;; if size is zero
jz.d [blink]
mov r3, r0 ; don't clobber ret val
;;; if length < 8
brls.d.nt r2, 8, .Lsmallchunk
mov.f lp_count,r2
and.f r4, r0, 0x03
rsub lp_count, r4, 4
lpnz @.Laligndestination
;; LOOP BEGIN
stb.ab r1, [r3,1]
sub r2, r2, 1
.Laligndestination:
;;; Destination is aligned
and r1, r1, 0xFF
asl r4, r1, 8
or r4, r4, r1
asl r5, r4, 16
or r5, r5, r4
mov r4, r5
sub3 lp_count, r2, 8
cmp r2, 64
bmsk.hi r2, r2, 5
mov.ls lp_count, 0
add3.hi r2, r2, 8
;;; Convert len to Dwords, unfold x8
lsr.f lp_count, lp_count, 6
lpnz @.Lset64bytes
;; LOOP START
PREALLOC_INSTR r3, 64 ; alloc next line w/o fetching
#ifdef [31mCONFIG_ARC_HAS_LL64[0m
std.ab r4, [r3, 8]
std.ab r4, [r3, 8]
std.ab r4, [r3, 8]
std.ab r4, [r3, 8]
std.ab r4, [r3, 8]
std.ab r4, [r3, 8]
std.ab r4, [r3, 8]
std.ab r4, [r3, 8]
#else
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
#endif
.Lset64bytes:
lsr.f lp_count, r2, 5 ;Last remaining max 124 bytes
lpnz .Lset32bytes
;; LOOP START
#ifdef [31mCONFIG_ARC_HAS_LL64[0m
std.ab r4, [r3, 8]
std.ab r4, [r3, 8]
std.ab r4, [r3, 8]
std.ab r4, [r3, 8]
#else
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
st.ab r4, [r3, 4]
#endif
.Lset32bytes:
and.f lp_count, r2, 0x1F ;Last remaining 31 bytes
.Lsmallchunk:
lpnz .Lcopy3bytes
;; LOOP START
stb.ab r1, [r3, 1]
.Lcopy3bytes:
j [blink]
END_CFI(memset)
ENTRY_CFI(memzero)
; adjust bzero args to memset args
mov r2, r1
b.d memset ;tail call so need to tinker with blink
mov r1, 0
END_CFI(memzero)