summaryrefslogtreecommitdiffstats
path: root/arch/arm/mm/copypage-v4wt.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mm/copypage-v4wt.S')
-rw-r--r--arch/arm/mm/copypage-v4wt.S73
1 files changed, 73 insertions, 0 deletions
diff --git a/arch/arm/mm/copypage-v4wt.S b/arch/arm/mm/copypage-v4wt.S
new file mode 100644
index 000000000000..976793937a93
--- /dev/null
+++ b/arch/arm/mm/copypage-v4wt.S
@@ -0,0 +1,73 @@
+/*
+ * linux/arch/arm/lib/copypage-v4.S
+ *
+ * Copyright (C) 1995-1999 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
+ *
+ * This is for CPUs with a writethrough cache and 'flush ID cache' is
+ * the only supported cache operation.
+ */
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <asm/constants.h>
+
+ .text
+ .align 5
+/*
+ * ARMv4 optimised copy_user_page
+ *
+ * Since we have writethrough caches, we don't have to worry about
+ * dirty data in the cache. However, we do have to ensure that
+ * subsequent reads are up to date.
+ */
+ENTRY(v4wt_copy_user_page)
+ stmfd sp!, {r4, lr} @ 2
+ mov r2, #PAGE_SZ/64 @ 1
+ ldmia r1!, {r3, r4, ip, lr} @ 4
+1: stmia r0!, {r3, r4, ip, lr} @ 4
+ ldmia r1!, {r3, r4, ip, lr} @ 4+1
+ stmia r0!, {r3, r4, ip, lr} @ 4
+ ldmia r1!, {r3, r4, ip, lr} @ 4
+ stmia r0!, {r3, r4, ip, lr} @ 4
+ ldmia r1!, {r3, r4, ip, lr} @ 4
+ subs r2, r2, #1 @ 1
+ stmia r0!, {r3, r4, ip, lr} @ 4
+ ldmneia r1!, {r3, r4, ip, lr} @ 4
+ bne 1b @ 1
+ mcr p15, 0, r2, c7, c7, 0 @ flush ID cache
+ ldmfd sp!, {r4, pc} @ 3
+
+ .align 5
+/*
+ * ARMv4 optimised clear_user_page
+ *
+ * Same story as above.
+ */
+ENTRY(v4wt_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: stmia r0!, {r2, r3, ip, lr} @ 4
+ stmia r0!, {r2, r3, ip, lr} @ 4
+ stmia r0!, {r2, r3, ip, lr} @ 4
+ stmia r0!, {r2, r3, ip, lr} @ 4
+ subs r1, r1, #1 @ 1
+ bne 1b @ 1
+ mcr p15, 0, r2, c7, c7, 0 @ flush ID cache
+ ldr pc, [sp], #4
+
+ __INITDATA
+
+ .type v4wt_user_fns, #object
+ENTRY(v4wt_user_fns)
+ .long v4wt_clear_user_page
+ .long v4wt_copy_user_page
+ .size v4wt_user_fns, . - v4wt_user_fns