v4.19.13 snapshot.
diff --git a/arch/arc/mm/ioremap.c b/arch/arc/mm/ioremap.c
new file mode 100644
index 0000000..9881bd7
--- /dev/null
+++ b/arch/arc/mm/ioremap.c
@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * 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.
+ */
+
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/cache.h>
+
+static inline bool arc_uncached_addr_space(phys_addr_t paddr)
+{
+ if (is_isa_arcompact()) {
+ if (paddr >= ARC_UNCACHED_ADDR_SPACE)
+ return true;
+ } else if (paddr >= perip_base && paddr <= perip_end) {
+ return true;
+ }
+
+ return false;
+}
+
+void __iomem *ioremap(phys_addr_t paddr, unsigned long size)
+{
+ phys_addr_t end;
+
+ /* Don't allow wraparound or zero size */
+ end = paddr + size - 1;
+ if (!size || (end < paddr))
+ return NULL;
+
+ /*
+ * If the region is h/w uncached, MMU mapping can be elided as optim
+ * The cast to u32 is fine as this region can only be inside 4GB
+ */
+ if (arc_uncached_addr_space(paddr))
+ return (void __iomem *)(u32)paddr;
+
+ return ioremap_prot(paddr, size, PAGE_KERNEL_NO_CACHE);
+}
+EXPORT_SYMBOL(ioremap);
+
+/*
+ * ioremap with access flags
+ * Cache semantics wise it is same as ioremap - "forced" uncached.
+ * However unlike vanilla ioremap which bypasses ARC MMU for addresses in
+ * ARC hardware uncached region, this one still goes thru the MMU as caller
+ * might need finer access control (R/W/X)
+ */
+void __iomem *ioremap_prot(phys_addr_t paddr, unsigned long size,
+ unsigned long flags)
+{
+ unsigned long vaddr;
+ struct vm_struct *area;
+ phys_addr_t off, end;
+ pgprot_t prot = __pgprot(flags);
+
+ /* Don't allow wraparound, zero size */
+ end = paddr + size - 1;
+ if ((!size) || (end < paddr))
+ return NULL;
+
+ /* An early platform driver might end up here */
+ if (!slab_is_available())
+ return NULL;
+
+ /* force uncached */
+ prot = pgprot_noncached(prot);
+
+ /* Mappings have to be page-aligned */
+ off = paddr & ~PAGE_MASK;
+ paddr &= PAGE_MASK;
+ size = PAGE_ALIGN(end + 1) - paddr;
+
+ /*
+ * Ok, go for it..
+ */
+ area = get_vm_area(size, VM_IOREMAP);
+ if (!area)
+ return NULL;
+ area->phys_addr = paddr;
+ vaddr = (unsigned long)area->addr;
+ if (ioremap_page_range(vaddr, vaddr + size, paddr, prot)) {
+ vunmap((void __force *)vaddr);
+ return NULL;
+ }
+ return (void __iomem *)(off + (char __iomem *)vaddr);
+}
+EXPORT_SYMBOL(ioremap_prot);
+
+
+void iounmap(const void __iomem *addr)
+{
+ /* weird double cast to handle phys_addr_t > 32 bits */
+ if (arc_uncached_addr_space((phys_addr_t)(u32)addr))
+ return;
+
+ vfree((void *)(PAGE_MASK & (unsigned long __force)addr));
+}
+EXPORT_SYMBOL(iounmap);