aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/mm/copypage-v4wt.c
diff options
context:
space:
mode:
authorRussell King <rmk@dyn-67.arm.linux.org.uk>2008-11-28 10:39:02 -0500
committerRussell King <rmk+kernel@arm.linux.org.uk>2008-11-28 10:39:02 -0500
commit7ef4de17cc55a3c3b8d093743b1e3b845d8eba47 (patch)
treeadf87c996affbb6c42850d55cb34c0e5a2f6d340 /arch/arm/mm/copypage-v4wt.c
parentf412b09f4ed7c57f5b8935ed7d6fc786f402a629 (diff)
parentb5ee9002583fc14e6d45a04c18f208987a8fbced (diff)
Merge branch 'highmem' into devel
Conflicts: arch/arm/mach-clps7500/include/mach/memory.h
Diffstat (limited to 'arch/arm/mm/copypage-v4wt.c')
-rw-r--r--arch/arm/mm/copypage-v4wt.c88
1 files changed, 88 insertions, 0 deletions
diff --git a/arch/arm/mm/copypage-v4wt.c b/arch/arm/mm/copypage-v4wt.c
new file mode 100644
index 000000000000..0f1188efae45
--- /dev/null
+++ b/arch/arm/mm/copypage-v4wt.c
@@ -0,0 +1,88 @@
1/*
2 * linux/arch/arm/mm/copypage-v4wt.S
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 * This is for CPUs with a writethrough cache and 'flush ID cache' is
11 * the only supported cache operation.
12 */
13#include <linux/init.h>
14#include <linux/highmem.h>
15
16/*
17 * ARMv4 optimised copy_user_highpage
18 *
19 * Since we have writethrough caches, we don't have to worry about
20 * dirty data in the cache. However, we do have to ensure that
21 * subsequent reads are up to date.
22 */
23static void __attribute__((naked))
24v4wt_copy_user_page(void *kto, const void *kfrom)
25{
26 asm("\
27 stmfd sp!, {r4, lr} @ 2\n\
28 mov r2, %0 @ 1\n\
29 ldmia r1!, {r3, r4, ip, lr} @ 4\n\
301: stmia r0!, {r3, r4, ip, lr} @ 4\n\
31 ldmia r1!, {r3, r4, ip, lr} @ 4+1\n\
32 stmia r0!, {r3, r4, ip, lr} @ 4\n\
33 ldmia r1!, {r3, r4, ip, lr} @ 4\n\
34 stmia r0!, {r3, r4, ip, lr} @ 4\n\
35 ldmia r1!, {r3, r4, ip, lr} @ 4\n\
36 subs r2, r2, #1 @ 1\n\
37 stmia r0!, {r3, r4, ip, lr} @ 4\n\
38 ldmneia r1!, {r3, r4, ip, lr} @ 4\n\
39 bne 1b @ 1\n\
40 mcr p15, 0, r2, c7, c7, 0 @ flush ID cache\n\
41 ldmfd sp!, {r4, pc} @ 3"
42 :
43 : "I" (PAGE_SIZE / 64));
44}
45
46void v4wt_copy_user_highpage(struct page *to, struct page *from,
47 unsigned long vaddr)
48{
49 void *kto, *kfrom;
50
51 kto = kmap_atomic(to, KM_USER0);
52 kfrom = kmap_atomic(from, KM_USER1);
53 v4wt_copy_user_page(kto, kfrom);
54 kunmap_atomic(kfrom, KM_USER1);
55 kunmap_atomic(kto, KM_USER0);
56}
57
58/*
59 * ARMv4 optimised clear_user_page
60 *
61 * Same story as above.
62 */
63void v4wt_clear_user_highpage(struct page *page, unsigned long vaddr)
64{
65 void *ptr, *kaddr = kmap_atomic(page, KM_USER0);
66 asm volatile("\
67 mov r1, %2 @ 1\n\
68 mov r2, #0 @ 1\n\
69 mov r3, #0 @ 1\n\
70 mov ip, #0 @ 1\n\
71 mov lr, #0 @ 1\n\
721: stmia %0!, {r2, r3, ip, lr} @ 4\n\
73 stmia %0!, {r2, r3, ip, lr} @ 4\n\
74 stmia %0!, {r2, r3, ip, lr} @ 4\n\
75 stmia %0!, {r2, r3, ip, lr} @ 4\n\
76 subs r1, r1, #1 @ 1\n\
77 bne 1b @ 1\n\
78 mcr p15, 0, r2, c7, c7, 0 @ flush ID cache"
79 : "=r" (ptr)
80 : "0" (kaddr), "I" (PAGE_SIZE / 64)
81 : "r1", "r2", "r3", "ip", "lr");
82 kunmap_atomic(kaddr, KM_USER0);
83}
84
85struct cpu_user_fns v4wt_user_fns __initdata = {
86 .cpu_clear_user_highpage = v4wt_clear_user_highpage,
87 .cpu_copy_user_highpage = v4wt_copy_user_highpage,
88};