/*
* Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
#ifdef __LITTLE_ENDIAN__
# define SHIFT_1(RX,RY,IMM) asl RX, RY, IMM ; <<
# define SHIFT_2(RX,RY,IMM) lsr RX, RY, IMM ; >>
# define MERGE_1(RX,RY,IMM) asl RX, RY, IMM
# define MERGE_2(RX,RY,IMM)
# define EXTRACT_1(RX,RY,IMM) and RX, RY, 0xFFFF
# define EXTRACT_2(RX,RY,IMM) lsr RX, RY, IMM
#else
# define SHIFT_1(RX,RY,IMM) lsr RX, RY, IMM ; >>
# define SHIFT_2(RX,RY,IMM) asl RX, RY, IMM ; <<
# define MERGE_1(RX,RY,IMM) asl RX, RY, IMM ; <<
# define MERGE_2(RX,RY,IMM) asl RX, RY, IMM ; <<
# define EXTRACT_1(RX,RY,IMM) lsr RX, RY, IMM
# define EXTRACT_2(RX,RY,IMM) lsr RX, RY, 0x08
#endif
#ifdef CONFIG_ARC_HAS_LL64
# define PREFETCH_READ(RX) prefetch [RX, 56]
# define PREFETCH_WRITE(RX) prefetchw [RX, 64]
# define LOADX(DST,RX) ldd.ab DST, [RX, 8]
# define STOREX(SRC,RX) std.ab SRC, [RX, 8]
# define ZOLSHFT 5
# define ZOLAND 0x1F
#else
# define PREFETCH_READ(RX) prefetch [RX, 28]
# define PREFETCH_WRITE(RX) prefetchw [RX, 32]
# define LOADX(DST,RX) ld.ab DST, [RX, 4]
# define STOREX(SRC,RX) st.ab SRC, [RX, 4]
# define ZOLSHFT 4
# define ZOLAND 0xF
#endif
ENTRY(memcpy)
prefetch [r1] ; Prefetch the read location
prefetchw [r0] ; Prefetch the write location
mov.f 0, r2
;;; if size is zero
jz.d [blink]
mov r3, r0 ; don;t clobber ret val
;;; if size <= 8
cmp r2, 8
bls.d @smallchunk
mov.f lp_count, r2
and.f r4, r0, 0x03
rsub lp_count, r4, 4
lpnz @aligndestination
;; LOOP BEGIN
ldb.ab r5, [r1,1]
sub r2, r2, 1
stb.ab r5, [r3,1]
aligndestination:
;;; Check the alignment of the source
and.f r4, r1, 0x03
bnz.d @sourceunaligned
;;; CASE 0: Both source and destination are 32bit aligned
;;; Convert len to Dwords, unfold x4
lsr.f lp_count, r2, ZOLSHFT
lpnz @copy32_64bytes
;; LOOP START
LOADX (r6, r1)
PREFETCH_READ (r1)
PREFETCH_WRITE (r3)
LOADX (r8, r1)
LOADX (r10, r1)
LOADX (r4, r1)
STOREX (r6, r3)
STOREX (r8, r3)
STOREX (r10, r3)
STOREX (r4, r3)
copy32_64bytes:
and.f lp_count, r2, ZOLAND ;Last remaining 31 bytes
smallchunk:
lpnz @copyremainingbytes
;; LOOP START
ldb.ab r5, [r1,1]
stb.ab r5, [r3,1]
copyremainingbytes:
j [blink]
;;; END CASE 0
sourceunaligned:
cmp r4, 2
beq.d @unalignedOffby2
sub r2, r2, 1
bhi.d @unalignedOffby3
ldb.ab r5, [r1, 1]
;;; CASE 1: The source is unaligned, off by 1
;; Hence I need to read 1 byte for a 16bit alignment
;; and 2bytes to reach 32bit alignment
ldh.ab r6, [r1, 2]
sub r2, r2, 2
;; Convert to words, unfold x2
lsr.f lp_count, r2, 3
MERGE_1 (r6, r6, 8)
MERGE_2 (r5, r5, 24)
or r5, r5, r6
;; Both src and dst are aligned
lpnz @copy8bytes_1
;; LOOP START
ld.ab r6, [r1, 4]
prefetch [r1, 28] ;Prefetch the next read location
ld.ab r8, [r1,4]
prefetchw [r3, 32] ;Prefetch the next write location
SHIFT_1 (r7, r6, 24)
or r7, r7, r5
SHIFT_2 (r5, r6, 8)
SHIFT_1 (r9, r8, 24)
or r9, r9, r5
SHIFT_2 (r5, r8, 8)
st.ab r7, [r3, 4]
st.ab r9, [r3, 4]
copy8bytes_1:
;; Write back the remaining 16bits
EXTRACT_1 (r6, r5, 16)
sth.ab r6, [r3, 2]
;; Write back the remaining 8bits
EXTRACT_2 (r5, r5, 16)
stb.ab r5, [r3, 1]
and.f lp_count, r2, 0x07 ;Last 8bytes
lpnz @copybytewise_1
;; LOOP START
ldb.ab r6, [r1,1]
stb.ab r6, [r3,1]
copybytewise_1:
j [blink]
unalignedOffby2:
;;; CASE 2: The source is unaligned, off by 2
ldh.ab r5, [r1, 2]
sub r2, r2, 1
;; Both src and dst are aligned
;; Convert to words, unfold x2
lsr.f lp_count, r2, 3
#ifdef __BIG_ENDIAN__
asl.nz r5, r5, 16
#endif
lpnz @copy8bytes_2
;; LOOP START
ld.ab r6, [r1, 4]
prefetch [r1, 28] ;Prefetch the next read location
ld.ab r8, [r1,4]
prefetchw [r3, 32] ;Prefetch the next write location
SHIFT_1 (r7, r6, 16)
or r7, r7, r5
SHIFT_2 (r5, r6, 16)
SHIFT_1 (r9, r8, 16)
or r9, r9, r5
SHIFT_2 (r5, r8, 16)
st.ab r7, [r3, 4]
st.ab r9, [r3, 4]
copy8bytes_2:
#ifdef __BIG_ENDIAN__
lsr.nz r5, r5, 16
#endif
sth.ab r5, [r3, 2]
and.f lp_count, r2, 0x07 ;Last 8bytes
lpnz @copybytewise_2
;; LOOP START
ldb.ab r6, [r1,1]
stb.ab r6, [r3,1]
copybytewise_2:
j [blink]
unalignedOffby3:
;;; CASE 3: The source is unaligned, off by 3
;;; Hence, I need to read 1byte for achieve the 32bit alignment
;; Both src and dst are aligned
;; Convert to words, unfold x2
lsr.f lp_count, r2, 3
#ifdef __BIG_ENDIAN__
asl.ne r5, r5, 24
#endif
lpnz @copy8bytes_3
;; LOOP START
ld.ab r6, [r1, 4]
prefetch [r1, 28] ;Prefetch the next read location
ld.ab r8, [r1,4]
prefetchw [r3, 32] ;Prefetch the next write location
SHIFT_1 (r7, r6, 8)
or r7, r7, r5
SHIFT_2 (r5, r6, 24)
SHIFT_1 (r9, r8, 8)
or r9, r9, r5
SHIFT_2 (r5, r8, 24)
st.ab r7, [r3, 4]
st.ab r9, [r3, 4]
copy8bytes_3:
#ifdef __BIG_ENDIAN__
lsr.nz r5, r5, 24
#endif
stb.ab r5, [r3, 1]
and.f lp_count, r2, 0x07 ;Last 8bytes
lpnz @copybytewise_3
;; LOOP START
ldb.ab r6, [r1,1]
stb.ab r6, [r3,1]
copybytewise_3:
j [blink]
END(memcpy)
