LXR linux/arch/arm/mm/copypage-fa.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *  linux/arch/arm/lib/copypage-fa.S
   4 *
   5 *  Copyright (C) 2005 Faraday Corp.
   6 *  Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
   7 *
   8 * Based on copypage-v4wb.S:
   9 *  Copyright (C) 1995-1999 Russell King
  10 */
  11#include <linux/init.h>
  12#include <linux/highmem.h>
  13
  14/*
  15 * Faraday optimised copy_user_page
  16 */
  17static void fa_copy_user_page(void *kto, const void *kfrom)
  18{
  19        int tmp;
  20
  21        asm volatile ("\
  221:      ldmia   %1!, {r3, r4, ip, lr}           @ 4\n\
  23        stmia   %0, {r3, r4, ip, lr}            @ 4\n\
  24        mcr     p15, 0, %0, c7, c14, 1          @ 1   clean and invalidate D line\n\
  25        add     %0, %0, #16                     @ 1\n\
  26        ldmia   %1!, {r3, r4, ip, lr}           @ 4\n\
  27        stmia   %0, {r3, r4, ip, lr}            @ 4\n\
  28        mcr     p15, 0, %0, c7, c14, 1          @ 1   clean and invalidate D line\n\
  29        add     %0, %0, #16                     @ 1\n\
  30        subs    %2, %2, #1                      @ 1\n\
  31        bne     1b                              @ 1\n\
  32        mcr     p15, 0, %2, c7, c10, 4          @ 1   drain WB"
  33        : "+&r" (kto), "+&r" (kfrom), "=&r" (tmp)
  34        : "2" (PAGE_SIZE / 32)
  35        : "r3", "r4", "ip", "lr");
  36}
  37
  38void fa_copy_user_highpage(struct page *to, struct page *from,
  39        unsigned long vaddr, struct vm_area_struct *vma)
  40{
  41        void *kto, *kfrom;
  42
  43        kto = kmap_atomic(to);
  44        kfrom = kmap_atomic(from);
  45        fa_copy_user_page(kto, kfrom);
  46        kunmap_atomic(kfrom);
  47        kunmap_atomic(kto);
  48}
  49
  50/*
  51 * Faraday optimised clear_user_page
  52 *
  53 * Same story as above.
  54 */
  55void fa_clear_user_highpage(struct page *page, unsigned long vaddr)
  56{
  57        void *ptr, *kaddr = kmap_atomic(page);
  58        asm volatile("\
  59        mov     r1, %2                          @ 1\n\
  60        mov     r2, #0                          @ 1\n\
  61        mov     r3, #0                          @ 1\n\
  62        mov     ip, #0                          @ 1\n\
  63        mov     lr, #0                          @ 1\n\
  641:      stmia   %0, {r2, r3, ip, lr}            @ 4\n\
  65        mcr     p15, 0, %0, c7, c14, 1          @ 1   clean and invalidate D line\n\
  66        add     %0, %0, #16                     @ 1\n\
  67        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        subs    r1, r1, #1                      @ 1\n\
  71        bne     1b                              @ 1\n\
  72        mcr     p15, 0, r1, c7, c10, 4          @ 1   drain WB"
  73        : "=r" (ptr)
  74        : "0" (kaddr), "I" (PAGE_SIZE / 32)
  75        : "r1", "r2", "r3", "ip", "lr");
  76        kunmap_atomic(kaddr);
  77}
  78
  79struct cpu_user_fns fa_user_fns __initdata = {
  80        .cpu_clear_user_highpage = fa_clear_user_highpage,
  81        .cpu_copy_user_highpage = fa_copy_user_highpage,
  82};
  83