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+/*
+ * linux/arch/arm/lib/copy_page-armv4mc.S
+ *
+ * Copyright (C) 1995-2001 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.
+ *
+ * ASM optimised string functions
+ */
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <asm/constants.h>
+
+ .text
+ .align 5
+/*
+ * ARMv4 mini-dcache optimised copy_user_page
+ *
+ * We flush the destination cache lines just before we write the data into the
+ * corresponding address. Since the Dcache is read-allocate, this removes the
+ * Dcache aliasing issue. The writes will be forwarded to the write buffer,
+ * and merged as appropriate.
+ *
+ * Note: We rely on all ARMv4 processors implementing the "invalidate D line"
+ * instruction. If your processor does not supply this, you have to write your
+ * own copy_user_page that does the right thing.
+ */
+ENTRY(v4_mc_copy_user_page)
+ stmfd sp!, {r4, lr} @ 2
+ mov r4, r0
+ mov r0, r1
+ bl map_page_minicache
+ mov r1, #PAGE_SZ/64 @ 1
+ ldmia r0!, {r2, r3, ip, lr} @ 4
+1: mcr p15, 0, r4, c7, c6, 1 @ 1 invalidate D line
+ stmia r4!, {r2, r3, ip, lr} @ 4
+ ldmia r0!, {r2, r3, ip, lr} @ 4+1
+ stmia r4!, {r2, r3, ip, lr} @ 4
+ ldmia r0!, {r2, r3, ip, lr} @ 4
+ mcr p15, 0, r4, c7, c6, 1 @ 1 invalidate D line
+ stmia r4!, {r2, r3, ip, lr} @ 4
+ ldmia r0!, {r2, r3, ip, lr} @ 4
+ subs r1, r1, #1 @ 1
+ stmia r4!, {r2, r3, ip, lr} @ 4
+ ldmneia r0!, {r2, r3, ip, lr} @ 4
+ bne 1b @ 1
+ ldmfd sp!, {r4, pc} @ 3
+
+ .align 5
+/*
+ * ARMv4 optimised clear_user_page
+ *
+ * Same story as above.
+ */
+ENTRY(v4_mc_clear_user_page)
+ str lr, [sp, #-4]!
+ mov r1, #PAGE_SZ/64 @ 1
+ mov r2, #0 @ 1
+ mov r3, #0 @ 1
+ mov ip, #0 @ 1
+ mov lr, #0 @ 1
+1: mcr p15, 0, r0, c7, c6, 1 @ 1 invalidate D line
+ stmia r0!, {r2, r3, ip, lr} @ 4
+ stmia r0!, {r2, r3, ip, lr} @ 4
+ mcr p15, 0, r0, c7, c6, 1 @ 1 invalidate D line
+ stmia r0!, {r2, r3, ip, lr} @ 4
+ stmia r0!, {r2, r3, ip, lr} @ 4
+ subs r1, r1, #1 @ 1
+ bne 1b @ 1
+ ldr pc, [sp], #4
+
+ __INITDATA
+
+ .type v4_mc_user_fns, #object
+ENTRY(v4_mc_user_fns)
+ .long v4_mc_clear_user_page
+ .long v4_mc_copy_user_page
+ .size v4_mc_user_fns, . - v4_mc_user_fns