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authorRussell King <rmk@dyn-67.arm.linux.org.uk>2008-10-31 14:08:02 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2008-11-28 00:53:46 +0100
commitd73e60b7144a86baf0fdfcc9537a70bb4f72e11c (patch)
tree02155154caf6f1a5d6ce38f2a89ed67f875c7791 /arch/arm/mm/copypage-v4wt.c
parentAllow architectures to override copy_user_highpage() (diff)
downloadlinux-d73e60b7144a86baf0fdfcc9537a70bb4f72e11c.tar.xz
linux-d73e60b7144a86baf0fdfcc9537a70bb4f72e11c.zip
[ARM] copypage: convert assembly files to C
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mm/copypage-v4wt.c')
-rw-r--r--arch/arm/mm/copypage-v4wt.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/arch/arm/mm/copypage-v4wt.c b/arch/arm/mm/copypage-v4wt.c
new file mode 100644
index 000000000000..d8ef39503ff0
--- /dev/null
+++ b/arch/arm/mm/copypage-v4wt.c
@@ -0,0 +1,77 @@
+/*
+ * linux/arch/arm/mm/copypage-v4wt.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.
+ *
+ * This is for CPUs with a writethrough cache and 'flush ID cache' is
+ * the only supported cache operation.
+ */
+#include <linux/init.h>
+
+#include <asm/page.h>
+
+/*
+ * 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.
+ */
+void __attribute__((naked))
+v4wt_copy_user_page(void *kto, const void *kfrom, unsigned long vaddr)
+{
+ asm("\
+ stmfd sp!, {r4, lr} @ 2\n\
+ mov r2, %0 @ 1\n\
+ ldmia r1!, {r3, r4, ip, lr} @ 4\n\
+1: stmia r0!, {r3, r4, ip, lr} @ 4\n\
+ ldmia r1!, {r3, r4, ip, lr} @ 4+1\n\
+ stmia r0!, {r3, r4, ip, lr} @ 4\n\
+ ldmia r1!, {r3, r4, ip, lr} @ 4\n\
+ stmia r0!, {r3, r4, ip, lr} @ 4\n\
+ ldmia r1!, {r3, r4, ip, lr} @ 4\n\
+ subs r2, r2, #1 @ 1\n\
+ stmia r0!, {r3, r4, ip, lr} @ 4\n\
+ ldmneia r1!, {r3, r4, ip, lr} @ 4\n\
+ bne 1b @ 1\n\
+ mcr p15, 0, r2, c7, c7, 0 @ flush ID cache\n\
+ ldmfd sp!, {r4, pc} @ 3"
+ :
+ : "I" (PAGE_SIZE / 64));
+}
+
+/*
+ * ARMv4 optimised clear_user_page
+ *
+ * Same story as above.
+ */
+void __attribute__((naked))
+v4wt_clear_user_page(void *kaddr, unsigned long vaddr)
+{
+ asm("\
+ str lr, [sp, #-4]!\n\
+ mov r1, %0 @ 1\n\
+ mov r2, #0 @ 1\n\
+ mov r3, #0 @ 1\n\
+ mov ip, #0 @ 1\n\
+ mov lr, #0 @ 1\n\
+1: stmia r0!, {r2, r3, ip, lr} @ 4\n\
+ stmia r0!, {r2, r3, ip, lr} @ 4\n\
+ stmia r0!, {r2, r3, ip, lr} @ 4\n\
+ stmia r0!, {r2, r3, ip, lr} @ 4\n\
+ subs r1, r1, #1 @ 1\n\
+ bne 1b @ 1\n\
+ mcr p15, 0, r2, c7, c7, 0 @ flush ID cache\n\
+ ldr pc, [sp], #4"
+ :
+ : "I" (PAGE_SIZE / 64));
+}
+
+struct cpu_user_fns v4wt_user_fns __initdata = {
+ .cpu_clear_user_page = v4wt_clear_user_page,
+ .cpu_copy_user_page = v4wt_copy_user_page,
+};