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 : "0" (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