1/*
 2 *  linux/arch/arm/mm/copypage-v3.c
 3 *
 4 *  Copyright (C) 1995-1999 Russell King
 5 *
 6 * This program is free software; you can redistribute it and/or modify
 7 * it under the terms of the GNU General Public License version 2 as
 8 * published by the Free Software Foundation.
 9 */
10#include <linux/init.h>
11#include <linux/highmem.h>
12
13/*
14 * ARMv3 optimised copy_user_highpage
15 *
16 * FIXME: do we need to handle cache stuff...
17 */
18static void __naked
19v3_copy_user_page(void *kto, const void *kfrom)
20{
21	asm("\n\
22	stmfd	sp!, {r4, lr}			@	2\n\
23	mov	r2, %2				@	1\n\
24	ldmia	%0!, {r3, r4, ip, lr}		@	4+1\n\
251:	stmia	%1!, {r3, r4, ip, lr}		@	4\n\
26	ldmia	%0!, {r3, r4, ip, lr}		@	4+1\n\
27	stmia	%1!, {r3, r4, ip, lr}		@	4\n\
28	ldmia	%0!, {r3, r4, ip, lr}		@	4+1\n\
29	stmia	%1!, {r3, r4, ip, lr}		@	4\n\
30	ldmia	%0!, {r3, r4, ip, lr}		@	4\n\
31	subs	r2, r2, #1			@	1\n\
32	stmia	%1!, {r3, r4, ip, lr}		@	4\n\
33	ldmneia	%0!, {r3, r4, ip, lr}		@	4\n\
34	bne	1b				@	1\n\
35	ldmfd	sp!, {r4, pc}			@	3"
36	:
37	: "r" (kfrom), "r" (kto), "I" (PAGE_SIZE / 64));
38}
39
40void v3_copy_user_highpage(struct page *to, struct page *from,
41	unsigned long vaddr, struct vm_area_struct *vma)
42{
43	void *kto, *kfrom;
44
45	kto = kmap_atomic(to, KM_USER0);
46	kfrom = kmap_atomic(from, KM_USER1);
47	v3_copy_user_page(kto, kfrom);
48	kunmap_atomic(kfrom, KM_USER1);
49	kunmap_atomic(kto, KM_USER0);
50}
51
52/*
53 * ARMv3 optimised clear_user_page
54 *
55 * FIXME: do we need to handle cache stuff...
56 */
57void v3_clear_user_highpage(struct page *page, unsigned long vaddr)
58{
59	void *ptr, *kaddr = kmap_atomic(page, KM_USER0);
60	asm volatile("\n\
61	mov	r1, %2				@ 1\n\
62	mov	r2, #0				@ 1\n\
63	mov	r3, #0				@ 1\n\
64	mov	ip, #0				@ 1\n\
65	mov	lr, #0				@ 1\n\
661:	stmia	%0!, {r2, r3, ip, lr}		@ 4\n\
67	stmia	%0!, {r2, r3, ip, lr}		@ 4\n\
68	stmia	%0!, {r2, r3, ip, lr}		@ 4\n\
69	stmia	%0!, {r2, r3, ip, lr}		@ 4\n\
70	subs	r1, r1, #1			@ 1\n\
71	bne	1b				@ 1"
72	: "=r" (ptr)
73	: "0" (kaddr), "I" (PAGE_SIZE / 64)
74	: "r1", "r2", "r3", "ip", "lr");
75	kunmap_atomic(kaddr, KM_USER0);
76}
77
78struct cpu_user_fns v3_user_fns __initdata = {
79	.cpu_clear_user_highpage = v3_clear_user_highpage,
80	.cpu_copy_user_highpage	= v3_copy_user_highpage,
81};