aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/mm/copypage-xscale.S
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/mm/copypage-xscale.S
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/arm/mm/copypage-xscale.S')
-rw-r--r--arch/arm/mm/copypage-xscale.S113
1 files changed, 113 insertions, 0 deletions
diff --git a/arch/arm/mm/copypage-xscale.S b/arch/arm/mm/copypage-xscale.S
new file mode 100644
index 000000000000..bb277316ef52
--- /dev/null
+++ b/arch/arm/mm/copypage-xscale.S
@@ -0,0 +1,113 @@
1/*
2 * linux/arch/arm/lib/copypage-xscale.S
3 *
4 * Copyright (C) 2001 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/linkage.h>
11#include <linux/init.h>
12#include <asm/constants.h>
13
14/*
15 * General note:
16 * We don't really want write-allocate cache behaviour for these functions
17 * since that will just eat through 8K of the cache.
18 */
19
20 .text
21 .align 5
22/*
23 * XScale optimised copy_user_page
24 * r0 = destination
25 * r1 = source
26 * r2 = virtual user address of ultimate destination page
27 *
28 * The source page may have some clean entries in the cache already, but we
29 * can safely ignore them - break_cow() will flush them out of the cache
30 * if we eventually end up using our copied page.
31 *
32 * What we could do is use the mini-cache to buffer reads from the source
33 * page. We rely on the mini-cache being smaller than one page, so we'll
34 * cycle through the complete cache anyway.
35 */
36ENTRY(xscale_mc_copy_user_page)
37 stmfd sp!, {r4, r5, lr}
38 mov r5, r0
39 mov r0, r1
40 bl map_page_minicache
41 mov r1, r5
42 mov lr, #PAGE_SZ/64-1
43
44 /*
45 * Strangely enough, best performance is achieved
46 * when prefetching destination as well. (NP)
47 */
48 pld [r0, #0]
49 pld [r0, #32]
50 pld [r1, #0]
51 pld [r1, #32]
52
531: pld [r0, #64]
54 pld [r0, #96]
55 pld [r1, #64]
56 pld [r1, #96]
57
582: ldrd r2, [r0], #8
59 ldrd r4, [r0], #8
60 mov ip, r1
61 strd r2, [r1], #8
62 ldrd r2, [r0], #8
63 strd r4, [r1], #8
64 ldrd r4, [r0], #8
65 strd r2, [r1], #8
66 strd r4, [r1], #8
67 mcr p15, 0, ip, c7, c10, 1 @ clean D line
68 ldrd r2, [r0], #8
69 mcr p15, 0, ip, c7, c6, 1 @ invalidate D line
70 ldrd r4, [r0], #8
71 mov ip, r1
72 strd r2, [r1], #8
73 ldrd r2, [r0], #8
74 strd r4, [r1], #8
75 ldrd r4, [r0], #8
76 strd r2, [r1], #8
77 strd r4, [r1], #8
78 mcr p15, 0, ip, c7, c10, 1 @ clean D line
79 subs lr, lr, #1
80 mcr p15, 0, ip, c7, c6, 1 @ invalidate D line
81 bgt 1b
82 beq 2b
83
84 ldmfd sp!, {r4, r5, pc}
85
86 .align 5
87/*
88 * XScale optimised clear_user_page
89 * r0 = destination
90 * r1 = virtual user address of ultimate destination page
91 */
92ENTRY(xscale_mc_clear_user_page)
93 mov r1, #PAGE_SZ/32
94 mov r2, #0
95 mov r3, #0
961: mov ip, r0
97 strd r2, [r0], #8
98 strd r2, [r0], #8
99 strd r2, [r0], #8
100 strd r2, [r0], #8
101 mcr p15, 0, ip, c7, c10, 1 @ clean D line
102 subs r1, r1, #1
103 mcr p15, 0, ip, c7, c6, 1 @ invalidate D line
104 bne 1b
105 mov pc, lr
106
107 __INITDATA
108
109 .type xscale_mc_user_fns, #object
110ENTRY(xscale_mc_user_fns)
111 .long xscale_mc_clear_user_page
112 .long xscale_mc_copy_user_page
113 .size xscale_mc_user_fns, . - xscale_mc_user_fns