diff options
Diffstat (limited to 'arch/arm/mm/copypage-xsc3.c')
-rw-r--r-- | arch/arm/mm/copypage-xsc3.c | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/arch/arm/mm/copypage-xsc3.c b/arch/arm/mm/copypage-xsc3.c new file mode 100644 index 000000000..c86e79677 --- /dev/null +++ b/arch/arm/mm/copypage-xsc3.c @@ -0,0 +1,104 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/arch/arm/mm/copypage-xsc3.S + * + * Copyright (C) 2004 Intel Corp. + * + * Adapted for 3rd gen XScale core, no more mini-dcache + * Author: Matt Gilbert (matthew.m.gilbert@intel.com) + */ +#include <linux/init.h> +#include <linux/highmem.h> + +/* + * General note: + * We don't really want write-allocate cache behaviour for these functions + * since that will just eat through 8K of the cache. + */ + +/* + * XSC3 optimised copy_user_highpage + * + * The source page may have some clean entries in the cache already, but we + * can safely ignore them - break_cow() will flush them out of the cache + * if we eventually end up using our copied page. + * + */ +static void xsc3_mc_copy_user_page(void *kto, const void *kfrom) +{ + int tmp; + + asm volatile ("\ +.arch xscale \n\ + pld [%1, #0] \n\ + pld [%1, #32] \n\ +1: pld [%1, #64] \n\ + pld [%1, #96] \n\ + \n\ +2: ldrd r2, r3, [%1], #8 \n\ + ldrd r4, r5, [%1], #8 \n\ + mcr p15, 0, %0, c7, c6, 1 @ invalidate\n\ + strd r2, r3, [%0], #8 \n\ + ldrd r2, r3, [%1], #8 \n\ + strd r4, r5, [%0], #8 \n\ + ldrd r4, r5, [%1], #8 \n\ + strd r2, r3, [%0], #8 \n\ + strd r4, r5, [%0], #8 \n\ + ldrd r2, r3, [%1], #8 \n\ + ldrd r4, r5, [%1], #8 \n\ + mcr p15, 0, %0, c7, c6, 1 @ invalidate\n\ + strd r2, r3, [%0], #8 \n\ + ldrd r2, r3, [%1], #8 \n\ + subs %2, %2, #1 \n\ + strd r4, r5, [%0], #8 \n\ + ldrd r4, r5, [%1], #8 \n\ + strd r2, r3, [%0], #8 \n\ + strd r4, r5, [%0], #8 \n\ + bgt 1b \n\ + beq 2b " + : "+&r" (kto), "+&r" (kfrom), "=&r" (tmp) + : "2" (PAGE_SIZE / 64 - 1) + : "r2", "r3", "r4", "r5"); +} + +void xsc3_mc_copy_user_highpage(struct page *to, struct page *from, + unsigned long vaddr, struct vm_area_struct *vma) +{ + void *kto, *kfrom; + + kto = kmap_atomic(to); + kfrom = kmap_atomic(from); + flush_cache_page(vma, vaddr, page_to_pfn(from)); + xsc3_mc_copy_user_page(kto, kfrom); + kunmap_atomic(kfrom); + kunmap_atomic(kto); +} + +/* + * XScale optimised clear_user_page + */ +void xsc3_mc_clear_user_highpage(struct page *page, unsigned long vaddr) +{ + void *ptr, *kaddr = kmap_atomic(page); + asm volatile ("\ +.arch xscale \n\ + mov r1, %2 \n\ + mov r2, #0 \n\ + mov r3, #0 \n\ +1: mcr p15, 0, %0, c7, c6, 1 @ invalidate line\n\ + strd r2, r3, [%0], #8 \n\ + strd r2, r3, [%0], #8 \n\ + strd r2, r3, [%0], #8 \n\ + strd r2, r3, [%0], #8 \n\ + subs r1, r1, #1 \n\ + bne 1b" + : "=r" (ptr) + : "0" (kaddr), "I" (PAGE_SIZE / 32) + : "r1", "r2", "r3"); + kunmap_atomic(kaddr); +} + +struct cpu_user_fns xsc3_mc_user_fns __initdata = { + .cpu_clear_user_highpage = xsc3_mc_clear_user_highpage, + .cpu_copy_user_highpage = xsc3_mc_copy_user_highpage, +}; |