| Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame^] | 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 | }; |