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 __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, %2 \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 : "r" (kto), "r" (kfrom), "I" (PAGE_SIZE / 64 - 1)); 71 } 72 73 void xsc3_mc_copy_user_highpage(struct page *to, struct page *from, 74 unsigned long vaddr, struct vm_area_struct *vma) 75 { 76 void *kto, *kfrom; 77 78 kto = kmap_atomic(to); 79 kfrom = kmap_atomic(from); 80 flush_cache_page(vma, vaddr, page_to_pfn(from)); 81 xsc3_mc_copy_user_page(kto, kfrom); 82 kunmap_atomic(kfrom); 83 kunmap_atomic(kto); 84 } 85 86 /* 87 * XScale optimised clear_user_page 88 * r0 = destination 89 * r1 = virtual user address of ultimate destination page 90 */ 91 void xsc3_mc_clear_user_highpage(struct page *page, unsigned long vaddr) 92 { 93 void *ptr, *kaddr = kmap_atomic(page); 94 asm volatile ("\ 95 mov r1, %2 \n\ 96 mov r2, #0 \n\ 97 mov r3, #0 \n\ 98 1: mcr p15, 0, %0, c7, c6, 1 @ invalidate line\n\ 99 strd r2, [%0], #8 \n\ 100 strd r2, [%0], #8 \n\ 101 strd r2, [%0], #8 \n\ 102 strd r2, [%0], #8 \n\ 103 subs r1, r1, #1 \n\ 104 bne 1b" 105 : "=r" (ptr) 106 : "0" (kaddr), "I" (PAGE_SIZE / 32) 107 : "r1", "r2", "r3"); 108 kunmap_atomic(kaddr); 109 } 110 111 struct cpu_user_fns xsc3_mc_user_fns __initdata = { 112 .cpu_clear_user_highpage = xsc3_mc_clear_user_highpage, 113 .cpu_copy_user_highpage = xsc3_mc_copy_user_highpage, 114 }; 115