xref: /linux/arch/x86/lib/copy_page_64.S (revision 7a9b709e7cc5ce1ffb84ce07bf6d157e1de758df)
1/* SPDX-License-Identifier: GPL-2.0 */
2/* Written 2003 by Andi Kleen, based on a kernel by Evandro Menezes */
3
4#include <linux/export.h>
5#include <linux/linkage.h>
6#include <linux/cfi_types.h>
7#include <asm/cpufeatures.h>
8#include <asm/alternative.h>
9
10/*
11 * Some CPUs run faster using the string copy instructions (sane microcode).
12 * It is also a lot simpler. Use this when possible. But, don't use streaming
13 * copy unless the CPU indicates X86_FEATURE_REP_GOOD. Could vary the
14 * prefetch distance based on SMP/UP.
15 */
16	ALIGN
17SYM_TYPED_FUNC_START(copy_page)
18	ALTERNATIVE "jmp copy_page_regs", "", X86_FEATURE_REP_GOOD
19	movl	$4096/8, %ecx
20	rep	movsq
21	RET
22SYM_FUNC_END(copy_page)
23EXPORT_SYMBOL(copy_page)
24
25SYM_FUNC_START_LOCAL(copy_page_regs)
26	subq	$2*8,	%rsp
27	movq	%rbx,	(%rsp)
28	movq	%r12,	1*8(%rsp)
29
30	movl	$(4096/64)-5,	%ecx
31	.p2align 4
32.Loop64:
33	dec	%rcx
34	movq	0x8*0(%rsi), %rax
35	movq	0x8*1(%rsi), %rbx
36	movq	0x8*2(%rsi), %rdx
37	movq	0x8*3(%rsi), %r8
38	movq	0x8*4(%rsi), %r9
39	movq	0x8*5(%rsi), %r10
40	movq	0x8*6(%rsi), %r11
41	movq	0x8*7(%rsi), %r12
42
43	prefetcht0 5*64(%rsi)
44
45	movq	%rax, 0x8*0(%rdi)
46	movq	%rbx, 0x8*1(%rdi)
47	movq	%rdx, 0x8*2(%rdi)
48	movq	%r8,  0x8*3(%rdi)
49	movq	%r9,  0x8*4(%rdi)
50	movq	%r10, 0x8*5(%rdi)
51	movq	%r11, 0x8*6(%rdi)
52	movq	%r12, 0x8*7(%rdi)
53
54	leaq	64 (%rsi), %rsi
55	leaq	64 (%rdi), %rdi
56
57	jnz	.Loop64
58
59	movl	$5, %ecx
60	.p2align 4
61.Loop2:
62	decl	%ecx
63
64	movq	0x8*0(%rsi), %rax
65	movq	0x8*1(%rsi), %rbx
66	movq	0x8*2(%rsi), %rdx
67	movq	0x8*3(%rsi), %r8
68	movq	0x8*4(%rsi), %r9
69	movq	0x8*5(%rsi), %r10
70	movq	0x8*6(%rsi), %r11
71	movq	0x8*7(%rsi), %r12
72
73	movq	%rax, 0x8*0(%rdi)
74	movq	%rbx, 0x8*1(%rdi)
75	movq	%rdx, 0x8*2(%rdi)
76	movq	%r8,  0x8*3(%rdi)
77	movq	%r9,  0x8*4(%rdi)
78	movq	%r10, 0x8*5(%rdi)
79	movq	%r11, 0x8*6(%rdi)
80	movq	%r12, 0x8*7(%rdi)
81
82	leaq	64(%rdi), %rdi
83	leaq	64(%rsi), %rsi
84	jnz	.Loop2
85
86	movq	(%rsp), %rbx
87	movq	1*8(%rsp), %r12
88	addq	$2*8, %rsp
89	RET
90SYM_FUNC_END(copy_page_regs)
91