1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *
4  * Optimized version of the standard copy_page() function
5  *
6  * Inputs:
7  *	in0:	address of target page
8  *	in1:	address of source page
9  * Output:
10  *	no return value
11  *
12  * Copyright (C) 1999, 2001 Hewlett-Packard Co
13  *	Stephane Eranian <eranian@hpl.hp.com>
14  *	David Mosberger <davidm@hpl.hp.com>
15  *
16  * 4/06/01 davidm	Tuned to make it perform well both for cached and uncached copies.
17  */
18 #include <linux/export.h>
19 #include <asm/asmmacro.h>
20 #include <asm/page.h>
21 
22 #define PIPE_DEPTH	3
23 #define EPI		p[PIPE_DEPTH-1]
24 
25 #define lcount		r16
26 #define saved_pr	r17
27 #define saved_lc	r18
28 #define saved_pfs	r19
29 #define src1		r20
30 #define src2		r21
31 #define tgt1		r22
32 #define tgt2		r23
33 #define srcf		r24
34 #define tgtf		r25
35 #define tgt_last	r26
36 
37 #define Nrot		((8*PIPE_DEPTH+7)&~7)
38 
39 GLOBAL_ENTRY(copy_page)
40 	.prologue
41 	.save ar.pfs, saved_pfs
42 	alloc saved_pfs=ar.pfs,3,Nrot-3,0,Nrot
43 
44 	.rotr t1[PIPE_DEPTH], t2[PIPE_DEPTH], t3[PIPE_DEPTH], t4[PIPE_DEPTH], \
45 	      t5[PIPE_DEPTH], t6[PIPE_DEPTH], t7[PIPE_DEPTH], t8[PIPE_DEPTH]
46 	.rotp p[PIPE_DEPTH]
47 
48 	.save ar.lc, saved_lc
49 	mov saved_lc=ar.lc
50 	mov ar.ec=PIPE_DEPTH
51 
52 	mov lcount=PAGE_SIZE/64-1
53 	.save pr, saved_pr
54 	mov saved_pr=pr
55 	mov pr.rot=1<<16
56 
57 	.body
58 
59 	mov src1=in1
60 	adds src2=8,in1
61 	mov tgt_last = PAGE_SIZE
62 	;;
63 	adds tgt2=8,in0
64 	add srcf=512,in1
65 	mov ar.lc=lcount
66 	mov tgt1=in0
67 	add tgtf=512,in0
68 	add tgt_last = tgt_last, in0
69 	;;
70 1:
71 (p[0])	ld8 t1[0]=[src1],16
72 (EPI)	st8 [tgt1]=t1[PIPE_DEPTH-1],16
73 (p[0])	ld8 t2[0]=[src2],16
74 (EPI)	st8 [tgt2]=t2[PIPE_DEPTH-1],16
75 	cmp.ltu p6,p0 = tgtf, tgt_last
76 	;;
77 (p[0])	ld8 t3[0]=[src1],16
78 (EPI)	st8 [tgt1]=t3[PIPE_DEPTH-1],16
79 (p[0])	ld8 t4[0]=[src2],16
80 (EPI)	st8 [tgt2]=t4[PIPE_DEPTH-1],16
81 	;;
82 (p[0])	ld8 t5[0]=[src1],16
83 (EPI)	st8 [tgt1]=t5[PIPE_DEPTH-1],16
84 (p[0])	ld8 t6[0]=[src2],16
85 (EPI)	st8 [tgt2]=t6[PIPE_DEPTH-1],16
86 	;;
87 (p[0])	ld8 t7[0]=[src1],16
88 (EPI)	st8 [tgt1]=t7[PIPE_DEPTH-1],16
89 (p[0])	ld8 t8[0]=[src2],16
90 (EPI)	st8 [tgt2]=t8[PIPE_DEPTH-1],16
91 
92 (p6)	lfetch [srcf], 64
93 (p6)	lfetch [tgtf], 64
94 	br.ctop.sptk.few 1b
95 	;;
96 	mov pr=saved_pr,0xffffffffffff0000	// restore predicates
97 	mov ar.pfs=saved_pfs
98 	mov ar.lc=saved_lc
99 	br.ret.sptk.many rp
100 END(copy_page)
101 EXPORT_SYMBOL(copy_page)
102