Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6] / arch / arm / mm / copypage-xsc3.c
1 /*
2  *  linux/arch/arm/mm/copypage-xsc3.S
3  *
4  *  Copyright (C) 2004 Intel Corp.
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  * Adapted for 3rd gen XScale core, no more mini-dcache
11  * Author: Matt Gilbert (matthew.m.gilbert@intel.com)
12  */
13 #include <linux/init.h>
14 #include <linux/highmem.h>
15
16 /*
17  * General note:
18  *  We don't really want write-allocate cache behaviour for these functions
19  *  since that will just eat through 8K of the cache.
20  */
21
22 /*
23  * XSC3 optimised copy_user_highpage
24  *  r0 = destination
25  *  r1 = source
26  *
27  * The source page may have some clean entries in the cache already, but we
28  * can safely ignore them - break_cow() will flush them out of the cache
29  * if we eventually end up using our copied page.
30  *
31  */
32 static void __attribute__((naked))
33 xsc3_mc_copy_user_page(void *kto, const void *kfrom)
34 {
35         asm("\
36         stmfd   sp!, {r4, r5, lr}               \n\
37         mov     lr, %0                          \n\
38                                                 \n\
39         pld     [r1, #0]                        \n\
40         pld     [r1, #32]                       \n\
41 1:      pld     [r1, #64]                       \n\
42         pld     [r1, #96]                       \n\
43                                                 \n\
44 2:      ldrd    r2, [r1], #8                    \n\
45         mov     ip, r0                          \n\
46         ldrd    r4, [r1], #8                    \n\
47         mcr     p15, 0, ip, c7, c6, 1           @ invalidate\n\
48         strd    r2, [r0], #8                    \n\
49         ldrd    r2, [r1], #8                    \n\
50         strd    r4, [r0], #8                    \n\
51         ldrd    r4, [r1], #8                    \n\
52         strd    r2, [r0], #8                    \n\
53         strd    r4, [r0], #8                    \n\
54         ldrd    r2, [r1], #8                    \n\
55         mov     ip, r0                          \n\
56         ldrd    r4, [r1], #8                    \n\
57         mcr     p15, 0, ip, c7, c6, 1           @ invalidate\n\
58         strd    r2, [r0], #8                    \n\
59         ldrd    r2, [r1], #8                    \n\
60         subs    lr, lr, #1                      \n\
61         strd    r4, [r0], #8                    \n\
62         ldrd    r4, [r1], #8                    \n\
63         strd    r2, [r0], #8                    \n\
64         strd    r4, [r0], #8                    \n\
65         bgt     1b                              \n\
66         beq     2b                              \n\
67                                                 \n\
68         ldmfd   sp!, {r4, r5, pc}"
69         :
70         : "I" (PAGE_SIZE / 64 - 1));
71 }
72
73 void xsc3_mc_copy_user_highpage(struct page *to, struct page *from,
74         unsigned long vaddr)
75 {
76         void *kto, *kfrom;
77
78         kto = kmap_atomic(to, KM_USER0);
79         kfrom = kmap_atomic(from, KM_USER1);
80         xsc3_mc_copy_user_page(kto, kfrom);
81         kunmap_atomic(kfrom, KM_USER1);
82         kunmap_atomic(kto, KM_USER0);
83 }
84
85 /*
86  * XScale optimised clear_user_page
87  *  r0 = destination
88  *  r1 = virtual user address of ultimate destination page
89  */
90 void xsc3_mc_clear_user_highpage(struct page *page, unsigned long vaddr)
91 {
92         void *ptr, *kaddr = kmap_atomic(page, KM_USER0);
93         asm volatile ("\
94         mov     r1, %2                          \n\
95         mov     r2, #0                          \n\
96         mov     r3, #0                          \n\
97 1:      mcr     p15, 0, %0, c7, c6, 1           @ invalidate line\n\
98         strd    r2, [%0], #8                    \n\
99         strd    r2, [%0], #8                    \n\
100         strd    r2, [%0], #8                    \n\
101         strd    r2, [%0], #8                    \n\
102         subs    r1, r1, #1                      \n\
103         bne     1b"
104         : "=r" (ptr)
105         : "0" (kaddr), "I" (PAGE_SIZE / 32)
106         : "r1", "r2", "r3");
107         kunmap_atomic(kaddr, KM_USER0);
108 }
109
110 struct cpu_user_fns xsc3_mc_user_fns __initdata = {
111         .cpu_clear_user_highpage = xsc3_mc_clear_user_highpage,
112         .cpu_copy_user_highpage = xsc3_mc_copy_user_highpage,
113 };