Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 114 insertions, 0 deletions

diff --git a/kernel/arch/arm/mm/copypage-xsc3.c b/kernel/arch/arm/mm/copypage-xsc3.c
new file mode 100644
index 000000000..03a2042ac
--- /dev/null
+++ b/kernel/arch/arm/mm/copypage-xsc3.c
@@ -0,0 +1,114 @@
+/*
+ *  linux/arch/arm/mm/copypage-xsc3.S
+ *
+ *  Copyright (C) 2004 Intel Corp.
+ *
+ * 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.
+ *
+ * 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
+ *  r0 = destination
+ *  r1 = source
+ *
+ * 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 __naked
+xsc3_mc_copy_user_page(void *kto, const void *kfrom)
+{
+	asm("\
+	stmfd	sp!, {r4, r5, lr}		\n\
+	mov	lr, %2				\n\
+						\n\
+	pld	[r1, #0]			\n\
+	pld	[r1, #32]			\n\
+1:	pld	[r1, #64]			\n\
+	pld	[r1, #96]			\n\
+						\n\
+2:	ldrd	r2, [r1], #8			\n\
+	mov	ip, r0				\n\
+	ldrd	r4, [r1], #8			\n\
+	mcr	p15, 0, ip, c7, c6, 1		@ invalidate\n\
+	strd	r2, [r0], #8			\n\
+	ldrd	r2, [r1], #8			\n\
+	strd	r4, [r0], #8			\n\
+	ldrd	r4, [r1], #8			\n\
+	strd	r2, [r0], #8			\n\
+	strd	r4, [r0], #8			\n\
+	ldrd	r2, [r1], #8			\n\
+	mov	ip, r0				\n\
+	ldrd	r4, [r1], #8			\n\
+	mcr	p15, 0, ip, c7, c6, 1		@ invalidate\n\
+	strd	r2, [r0], #8			\n\
+	ldrd	r2, [r1], #8			\n\
+	subs	lr, lr, #1			\n\
+	strd	r4, [r0], #8			\n\
+	ldrd	r4, [r1], #8			\n\
+	strd	r2, [r0], #8			\n\
+	strd	r4, [r0], #8			\n\
+	bgt	1b				\n\
+	beq	2b				\n\
+						\n\
+	ldmfd	sp!, {r4, r5, pc}"
+	:
+	: "r" (kto), "r" (kfrom), "I" (PAGE_SIZE / 64 - 1));
+}
+
+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
+ *  r0 = destination
+ *  r1 = virtual user address of ultimate destination page
+ */
+void xsc3_mc_clear_user_highpage(struct page *page, unsigned long vaddr)
+{
+	void *ptr, *kaddr = kmap_atomic(page);
+	asm volatile ("\
+	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, [%0], #8			\n\
+	strd	r2, [%0], #8			\n\
+	strd	r2, [%0], #8			\n\
+	strd	r2, [%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,
+};