/* * linux/arch/arm/lib/copypage-xscale.S * * Copyright (C) 2001 Russell King * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <linux/linkage.h> #include <asm/constants.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. */ .text .align 5 /* * XScale optimised copy_user_page * r0 = destination * r1 = source * r2 = virtual user address of ultimate destination page * * 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. * * What we could do is use the mini-cache to buffer reads from the source * page. We rely on the mini-cache being smaller than one page, so we'll * cycle through the complete cache anyway. */ ENTRY(xscale_mc_copy_user_page) stmfd sp!, {r4, r5, lr} mov r5, r0 mov r0, r1 bl map_page_minicache mov r1, r5 mov lr, #PAGE_SZ/32 1: mov ip, r1 ldrd r2, [r0], #8 ldrd r4, [r0], #8 strd r2, [r1], #8 ldrd r2, [r0], #8 strd r4, [r1], #8 ldrd r4, [r0], #8 strd r2, [r1], #8 strd r4, [r1], #8 mcr p15, 0, ip, c7, c10, 1 @ clean D line mcr p15, 0, ip, c7, c6, 1 @ invalidate D line subs lr, lr, #1 bne 1b ldmfd sp!, {r4, r5, pc} .align 5 /* * XScale optimised clear_user_page * r0 = destination * r1 = virtual user address of ultimate destination page */ ENTRY(xscale_mc_clear_user_page) str lr, [sp, #-4]! mov r1, #PAGE_SZ/32 mov r2, #0 mov r3, #0 1: mov ip, r0 strd r2, [r0], #8 strd r2, [r0], #8 strd r2, [r0], #8 strd r2, [r0], #8 mcr p15, 0, ip, c7, c10, 1 @ clean D line mcr p15, 0, ip, c7, c6, 1 @ invalidate D line subs r1, r1, #1 bne 1b ldr pc, [sp], #4 .section ".text.init", #alloc, #execinstr ENTRY(xscale_mc_user_fns) .long xscale_mc_clear_user_page .long xscale_mc_copy_user_page