1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/arch/arm/mm/copypage-xsc3.S
4 *
5 * Copyright (C) 2004 Intel Corp.
6 *
7 * Adapted for 3rd gen XScale core, no more mini-dcache
8 * Author: Matt Gilbert (matthew.m.gilbert@intel.com)
9 */
10 #include <linux/init.h>
11 #include <linux/highmem.h>
12
13 /*
14 * General note:
15 * We don't really want write-allocate cache behaviour for these functions
16 * since that will just eat through 8K of the cache.
17 */
18
19 /*
20 * XSC3 optimised copy_user_highpage
21 *
22 * The source page may have some clean entries in the cache already, but we
23 * can safely ignore them - break_cow() will flush them out of the cache
24 * if we eventually end up using our copied page.
25 *
26 */
27 static void xsc3_mc_copy_user_page(void *kto, const void *kfrom)
28 {
29 int tmp;
30
31 asm volatile ("\
32 .arch xscale \n\
33 pld [%1, #0] \n\
34 pld [%1, #32] \n\
35 1: pld [%1, #64] \n\
36 pld [%1, #96] \n\
37 \n\
38 2: ldrd r2, r3, [%1], #8 \n\
39 ldrd r4, r5, [%1], #8 \n\
40 mcr p15, 0, %0, c7, c6, 1 @ invalidate\n\
41 strd r2, r3, [%0], #8 \n\
42 ldrd r2, r3, [%1], #8 \n\
43 strd r4, r5, [%0], #8 \n\
44 ldrd r4, r5, [%1], #8 \n\
45 strd r2, r3, [%0], #8 \n\
46 strd r4, r5, [%0], #8 \n\
47 ldrd r2, r3, [%1], #8 \n\
48 ldrd r4, r5, [%1], #8 \n\
49 mcr p15, 0, %0, c7, c6, 1 @ invalidate\n\
50 strd r2, r3, [%0], #8 \n\
51 ldrd r2, r3, [%1], #8 \n\
52 subs %2, %2, #1 \n\
53 strd r4, r5, [%0], #8 \n\
54 ldrd r4, r5, [%1], #8 \n\
55 strd r2, r3, [%0], #8 \n\
56 strd r4, r5, [%0], #8 \n\
57 bgt 1b \n\
58 beq 2b "
59 : "+&r" (kto), "+&r" (kfrom), "=&r" (tmp)
60 : "2" (PAGE_SIZE / 64 - 1)
61 : "r2", "r3", "r4", "r5");
62 }
63
64 void xsc3_mc_copy_user_highpage(struct page *to, struct page *from,
65 unsigned long vaddr, struct vm_area_struct *vma)
66 {
67 void *kto, *kfrom;
68
69 kto = kmap_atomic(to);
70 kfrom = kmap_atomic(from);
71 flush_cache_page(vma, vaddr, page_to_pfn(from));
72 xsc3_mc_copy_user_page(kto, kfrom);
73 kunmap_atomic(kfrom);
74 kunmap_atomic(kto);
75 }
76
77 /*
78 * XScale optimised clear_user_page
79 */
80 void xsc3_mc_clear_user_highpage(struct page *page, unsigned long vaddr)
81 {
82 void *ptr, *kaddr = kmap_atomic(page);
83 asm volatile ("\
84 .arch xscale \n\
85 mov r1, %2 \n\
86 mov r2, #0 \n\
87 mov r3, #0 \n\
88 1: mcr p15, 0, %0, c7, c6, 1 @ invalidate line\n\
89 strd r2, r3, [%0], #8 \n\
90 strd r2, r3, [%0], #8 \n\
91 strd r2, r3, [%0], #8 \n\
92 strd r2, r3, [%0], #8 \n\
93 subs r1, r1, #1 \n\
94 bne 1b"
95 : "=r" (ptr)
96 : "" (kaddr), "I" (PAGE_SIZE / 32)
97 : "r1", "r2", "r3");
98 kunmap_atomic(kaddr);
99 }
100
101 struct cpu_user_fns xsc3_mc_user_fns __initdata = {
102 .cpu_clear_user_highpage = xsc3_mc_clear_user_highpage,
103 .cpu_copy_user_highpage = xsc3_mc_copy_user_highpage,
104 };
105
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.