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 pld [%1, #0] \n\ 33 pld [%1, #32] \n\ 34 1: pld [%1, #64] \n\ 35 pld [%1, #96] \n\ 36 \n\ 37 2: ldrd r2, r3, [%1], #8 \n\ 38 ldrd r4, r5, [%1], #8 \n\ 39 mcr p15, 0, %0, c7, c6, 1 @ invalidate\n\ 40 strd r2, r3, [%0], #8 \n\ 41 ldrd r2, r3, [%1], #8 \n\ 42 strd r4, r5, [%0], #8 \n\ 43 ldrd r4, r5, [%1], #8 \n\ 44 strd r2, r3, [%0], #8 \n\ 45 strd r4, r5, [%0], #8 \n\ 46 ldrd r2, r3, [%1], #8 \n\ 47 ldrd r4, r5, [%1], #8 \n\ 48 mcr p15, 0, %0, c7, c6, 1 @ invalidate\n\ 49 strd r2, r3, [%0], #8 \n\ 50 ldrd r2, r3, [%1], #8 \n\ 51 subs %2, %2, #1 \n\ 52 strd r4, r5, [%0], #8 \n\ 53 ldrd r4, r5, [%1], #8 \n\ 54 strd r2, r3, [%0], #8 \n\ 55 strd r4, r5, [%0], #8 \n\ 56 bgt 1b \n\ 57 beq 2b " 58 : "+&r" (kto), "+&r" (kfrom), "=&r" (tmp) 59 : "2" (PAGE_SIZE / 64 - 1) 60 : "r2", "r3", "r4", "r5"); 61 } 62 63 void xsc3_mc_copy_user_highpage(struct page *to, struct page *from, 64 unsigned long vaddr, struct vm_area_struct *vma) 65 { 66 void *kto, *kfrom; 67 68 kto = kmap_atomic(to); 69 kfrom = kmap_atomic(from); 70 flush_cache_page(vma, vaddr, page_to_pfn(from)); 71 xsc3_mc_copy_user_page(kto, kfrom); 72 kunmap_atomic(kfrom); 73 kunmap_atomic(kto); 74 } 75 76 /* 77 * XScale optimised clear_user_page 78 */ 79 void xsc3_mc_clear_user_highpage(struct page *page, unsigned long vaddr) 80 { 81 void *ptr, *kaddr = kmap_atomic(page); 82 asm volatile ("\ 83 mov r1, %2 \n\ 84 mov r2, #0 \n\ 85 mov r3, #0 \n\ 86 1: mcr p15, 0, %0, c7, c6, 1 @ invalidate line\n\ 87 strd r2, r3, [%0], #8 \n\ 88 strd r2, r3, [%0], #8 \n\ 89 strd r2, r3, [%0], #8 \n\ 90 strd r2, r3, [%0], #8 \n\ 91 subs r1, r1, #1 \n\ 92 bne 1b" 93 : "=r" (ptr) 94 : "0" (kaddr), "I" (PAGE_SIZE / 32) 95 : "r1", "r2", "r3"); 96 kunmap_atomic(kaddr); 97 } 98 99 struct cpu_user_fns xsc3_mc_user_fns __initdata = { 100 .cpu_clear_user_highpage = xsc3_mc_clear_user_highpage, 101 .cpu_copy_user_highpage = xsc3_mc_copy_user_highpage, 102 }; 103