arch/arm/mm/copypage-fa.c

   1 /*
   2  *  linux/arch/arm/lib/copypage-fa.S
   3  *
   4  *  Copyright (C) 2005 Faraday Corp.
   5  *  Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
   6  *
   7  * Based on copypage-v4wb.S:
   8  *  Copyright (C) 1995-1999 Russell King
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14 #include <linux/init.h>
  15 #include <linux/highmem.h>
  16
  17 /*
  18  * Faraday optimised copy_user_page
  19  */
  20 static void fa_copy_user_page(void *kto, const void *kfrom)
  21 {
  22         int tmp;
  23
  24         asm volatile ("\
  25 1:      ldmia   %1!, {r3, r4, ip, lr}           @ 4\n\
  26         stmia   %0, {r3, r4, ip, lr}            @ 4\n\
  27         mcr     p15, 0, %0, c7, c14, 1          @ 1   clean and invalidate D line\n\
  28         add     %0, %0, #16                     @ 1\n\
  29         ldmia   %1!, {r3, r4, ip, lr}           @ 4\n\
  30         stmia   %0, {r3, r4, ip, lr}            @ 4\n\
  31         mcr     p15, 0, %0, c7, c14, 1          @ 1   clean and invalidate D line\n\
  32         add     %0, %0, #16                     @ 1\n\
  33         subs    %2, %2, #1                      @ 1\n\
  34         bne     1b                              @ 1\n\
  35         mcr     p15, 0, %2, c7, c10, 4          @ 1   drain WB"
  36         : "+&r" (kto), "+&r" (kfrom), "=&r" (tmp)
  37         : "2" (PAGE_SIZE / 32)
  38         : "r3", "r4", "ip", "lr");
  39 }
  40
  41 void fa_copy_user_highpage(struct page *to, struct page *from,
  42         unsigned long vaddr, struct vm_area_struct *vma)
  43 {
  44         void *kto, *kfrom;
  45
  46         kto = kmap_atomic(to);
  47         kfrom = kmap_atomic(from);
  48         fa_copy_user_page(kto, kfrom);
  49         kunmap_atomic(kfrom);
  50         kunmap_atomic(kto);
  51 }
  52
  53 /*
  54  * Faraday optimised clear_user_page
  55  *
  56  * Same story as above.
  57  */
  58 void fa_clear_user_highpage(struct page *page, unsigned long vaddr)
  59 {
  60         void *ptr, *kaddr = kmap_atomic(page);
  61         asm volatile("\
  62         mov     r1, %2                          @ 1\n\
  63         mov     r2, #0                          @ 1\n\
  64         mov     r3, #0                          @ 1\n\
  65         mov     ip, #0                          @ 1\n\
  66         mov     lr, #0                          @ 1\n\
  67 1:      stmia   %0, {r2, r3, ip, lr}            @ 4\n\
  68         mcr     p15, 0, %0, c7, c14, 1          @ 1   clean and invalidate D line\n\
  69         add     %0, %0, #16                     @ 1\n\
  70         stmia   %0, {r2, r3, ip, lr}            @ 4\n\
  71         mcr     p15, 0, %0, c7, c14, 1          @ 1   clean and invalidate D line\n\
  72         add     %0, %0, #16                     @ 1\n\
  73         subs    r1, r1, #1                      @ 1\n\
  74         bne     1b                              @ 1\n\
  75         mcr     p15, 0, r1, c7, c10, 4          @ 1   drain WB"
  76         : "=r" (ptr)
  77         : "0" (kaddr), "I" (PAGE_SIZE / 32)
  78         : "r1", "r2", "r3", "ip", "lr");
  79         kunmap_atomic(kaddr);
  80 }
  81
  82 struct cpu_user_fns fa_user_fns __initdata = {
  83         .cpu_clear_user_highpage = fa_clear_user_highpage,
  84         .cpu_copy_user_highpage = fa_copy_user_highpage,
  85 };