1 files changed, 110 insertions, 0 deletions
diff --git a/arch/arm64/mm/ioremap.c b/arch/arm64/mm/ioremap.c
new file mode 100644
index 000000000..f173a01a0
--- /dev/null
+++ b/arch/arm64/mm/ioremap.c
@@ -0,0 +1,110 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Based on arch/arm/mm/ioremap.c
+ *
+ * (C) Copyright 1995 1996 Linus Torvalds
+ * Hacked for ARM by Phil Blundell <philb@gnu.org>
+ * Hacked to allow all architectures to build, and various cleanups
+ * by Russell King
+ * Copyright (C) 2012 ARM Ltd.
+ */
+
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/io.h>
+#include <linux/memblock.h>
+
+#include <asm/fixmap.h>
+#include <asm/tlbflush.h>
+
+static void __iomem *__ioremap_caller(phys_addr_t phys_addr, size_t size,
+				      pgprot_t prot, void *caller)
+{
+	unsigned long last_addr;
+	unsigned long offset = phys_addr & ~PAGE_MASK;
+	int err;
+	unsigned long addr;
+	struct vm_struct *area;
+
+	/*
+	 * Page align the mapping address and size, taking account of any
+	 * offset.
+	 */
+	phys_addr &= PAGE_MASK;
+	size = PAGE_ALIGN(size + offset);
+
+	/*
+	 * Don't allow wraparound, zero size or outside PHYS_MASK.
+	 */
+	last_addr = phys_addr + size - 1;
+	if (!size || last_addr < phys_addr || (last_addr & ~PHYS_MASK))
+		return NULL;
+
+	/*
+	 * Don't allow RAM to be mapped.
+	 */
+	if (WARN_ON(pfn_valid(__phys_to_pfn(phys_addr))))
+		return NULL;
+
+	area = get_vm_area_caller(size, VM_IOREMAP, caller);
+	if (!area)
+		return NULL;
+	addr = (unsigned long)area->addr;
+	area->phys_addr = phys_addr;
+
+	err = ioremap_page_range(addr, addr + size, phys_addr, prot);
+	if (err) {
+		vunmap((void *)addr);
+		return NULL;
+	}
+
+	return (void __iomem *)(offset + addr);
+}
+
+void __iomem *__ioremap(phys_addr_t phys_addr, size_t size, pgprot_t prot)
+{
+	return __ioremap_caller(phys_addr, size, prot,
+				__builtin_return_address(0));
+}
+EXPORT_SYMBOL(__ioremap);
+
+void iounmap(volatile void __iomem *io_addr)
+{
+	unsigned long addr = (unsigned long)io_addr & PAGE_MASK;
+
+	/*
+	 * We could get an address outside vmalloc range in case
+	 * of ioremap_cache() reusing a RAM mapping.
+	 */
+	if (is_vmalloc_addr((void *)addr))
+		vunmap((void *)addr);
+}
+EXPORT_SYMBOL(iounmap);
+
+void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size)
+{
+	/* For normal memory we already have a cacheable mapping. */
+	if (pfn_valid(__phys_to_pfn(phys_addr)))
+		return (void __iomem *)__phys_to_virt(phys_addr);
+
+	return __ioremap_caller(phys_addr, size, __pgprot(PROT_NORMAL),
+				__builtin_return_address(0));
+}
+EXPORT_SYMBOL(ioremap_cache);
+
+/*
+ * Must be called after early_fixmap_init
+ */
+void __init early_ioremap_init(void)
+{
+	early_ioremap_setup();
+}
+
+bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
+				 unsigned long flags)
+{
+	unsigned long pfn = PHYS_PFN(offset);
+
+	return memblock_is_map_memory(pfn);
+}