ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/arch/arm/mm/copypage-v4wt.c b/marvell/linux/arch/arm/mm/copypage-v4wt.c
new file mode 100644
index 0000000..1fb1073
--- /dev/null
+++ b/marvell/linux/arch/arm/mm/copypage-v4wt.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/arch/arm/mm/copypage-v4wt.S
+ *
+ * Copyright (C) 1995-1999 Russell King
+ *
+ * This is for CPUs with a writethrough cache and 'flush ID cache' is
+ * the only supported cache operation.
+ */
+#include <linux/init.h>
+#include <linux/highmem.h>
+
+/*
+ * ARMv4 optimised copy_user_highpage
+ *
+ * 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.
+ */
+static void v4wt_copy_user_page(void *kto, const void *kfrom)
+{
+ int tmp;
+
+ asm volatile ("\
+ .syntax unified\n\
+ ldmia %1!, {r3, r4, ip, lr} @ 4\n\
+1: stmia %0!, {r3, r4, ip, lr} @ 4\n\
+ ldmia %1!, {r3, r4, ip, lr} @ 4+1\n\
+ stmia %0!, {r3, r4, ip, lr} @ 4\n\
+ ldmia %1!, {r3, r4, ip, lr} @ 4\n\
+ stmia %0!, {r3, r4, ip, lr} @ 4\n\
+ ldmia %1!, {r3, r4, ip, lr} @ 4\n\
+ subs %2, %2, #1 @ 1\n\
+ stmia %0!, {r3, r4, ip, lr} @ 4\n\
+ ldmiane %1!, {r3, r4, ip, lr} @ 4\n\
+ bne 1b @ 1\n\
+ mcr p15, 0, %2, c7, c7, 0 @ flush ID cache"
+ : "+&r" (kto), "+&r" (kfrom), "=&r" (tmp)
+ : "2" (PAGE_SIZE / 64)
+ : "r3", "r4", "ip", "lr");
+}
+
+void v4wt_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);
+ v4wt_copy_user_page(kto, kfrom);
+ kunmap_atomic(kfrom);
+ kunmap_atomic(kto);
+}
+
+/*
+ * ARMv4 optimised clear_user_page
+ *
+ * Same story as above.
+ */
+void v4wt_clear_user_highpage(struct page *page, unsigned long vaddr)
+{
+ void *ptr, *kaddr = kmap_atomic(page);
+ asm volatile("\
+ mov r1, %2 @ 1\n\
+ mov r2, #0 @ 1\n\
+ mov r3, #0 @ 1\n\
+ mov ip, #0 @ 1\n\
+ mov lr, #0 @ 1\n\
+1: stmia %0!, {r2, r3, ip, lr} @ 4\n\
+ stmia %0!, {r2, r3, ip, lr} @ 4\n\
+ stmia %0!, {r2, r3, ip, lr} @ 4\n\
+ stmia %0!, {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"
+ : "=r" (ptr)
+ : "0" (kaddr), "I" (PAGE_SIZE / 64)
+ : "r1", "r2", "r3", "ip", "lr");
+ kunmap_atomic(kaddr);
+}
+
+struct cpu_user_fns v4wt_user_fns __initdata = {
+ .cpu_clear_user_highpage = v4wt_clear_user_highpage,
+ .cpu_copy_user_highpage = v4wt_copy_user_highpage,
+};