diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h
index 7535dc7cc5aa18..bd68e1b7f29f34 100644
--- a/arch/arm64/include/asm/acpi.h
+++ b/arch/arm64/include/asm/acpi.h
@@ -50,9 +50,6 @@ pgprot_t __acpi_get_mem_attribute(phys_addr_t addr);
 void __iomem *acpi_os_ioremap(acpi_physical_address phys, acpi_size size);
 #define acpi_os_ioremap acpi_os_ioremap
 
-void __iomem *acpi_os_memmap(acpi_physical_address phys, acpi_size size);
-#define acpi_os_memmap acpi_os_memmap
-
 typedef u64 phys_cpuid_t;
 #define PHYS_CPUID_INVALID INVALID_HWID
 
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
index 1c9c2f7a1c04d4..f3851724fe3561 100644
--- a/arch/arm64/kernel/acpi.c
+++ b/arch/arm64/kernel/acpi.c
@@ -273,8 +273,7 @@ pgprot_t __acpi_get_mem_attribute(phys_addr_t addr)
 	return __pgprot(PROT_DEVICE_nGnRnE);
 }
 
-static void __iomem *__acpi_os_ioremap(acpi_physical_address phys,
-				       acpi_size size, bool memory)
+void __iomem *acpi_os_ioremap(acpi_physical_address phys, acpi_size size)
 {
 	efi_memory_desc_t *md, *region = NULL;
 	pgprot_t prot;
@@ -300,11 +299,9 @@ static void __iomem *__acpi_os_ioremap(acpi_physical_address phys,
 	 * It is fine for AML to remap regions that are not represented in the
 	 * EFI memory map at all, as it only describes normal memory, and MMIO
 	 * regions that require a virtual mapping to make them accessible to
-	 * the EFI runtime services. Determine the region default
-	 * attributes by checking the requested memory semantics.
+	 * the EFI runtime services.
 	 */
-	prot = memory ? __pgprot(PROT_NORMAL_NC) :
-			__pgprot(PROT_DEVICE_nGnRnE);
+	prot = __pgprot(PROT_DEVICE_nGnRnE);
 	if (region) {
 		switch (region->type) {
 		case EFI_LOADER_CODE:
@@ -364,16 +361,6 @@ static void __iomem *__acpi_os_ioremap(acpi_physical_address phys,
 	return __ioremap(phys, size, prot);
 }
 
-void __iomem *acpi_os_ioremap(acpi_physical_address phys, acpi_size size)
-{
-	return __acpi_os_ioremap(phys, size, false);
-}
-
-void __iomem *acpi_os_memmap(acpi_physical_address phys, acpi_size size)
-{
-	return __acpi_os_ioremap(phys, size, true);
-}
-
 /*
  * Claim Synchronous External Aborts as a firmware first notification.
  *
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index a43f1521efe6d9..45c5c0e45e3327 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -284,8 +284,7 @@ acpi_map_lookup_virt(void __iomem *virt, acpi_size size)
 #define should_use_kmap(pfn)   page_is_ram(pfn)
 #endif
 
-static void __iomem *acpi_map(acpi_physical_address pg_off, unsigned long pg_sz,
-			      bool memory)
+static void __iomem *acpi_map(acpi_physical_address pg_off, unsigned long pg_sz)
 {
 	unsigned long pfn;
 
@@ -295,8 +294,7 @@ static void __iomem *acpi_map(acpi_physical_address pg_off, unsigned long pg_sz,
 			return NULL;
 		return (void __iomem __force *)kmap(pfn_to_page(pfn));
 	} else
-		return memory ? acpi_os_memmap(pg_off, pg_sz) :
-				acpi_os_ioremap(pg_off, pg_sz);
+		return acpi_os_ioremap(pg_off, pg_sz);
 }
 
 static void acpi_unmap(acpi_physical_address pg_off, void __iomem *vaddr)
@@ -311,10 +309,9 @@ static void acpi_unmap(acpi_physical_address pg_off, void __iomem *vaddr)
 }
 
 /**
- * __acpi_os_map_iomem - Get a virtual address for a given physical address range.
+ * acpi_os_map_iomem - Get a virtual address for a given physical address range.
  * @phys: Start of the physical address range to map.
  * @size: Size of the physical address range to map.
- * @memory: true if remapping memory, false if IO
  *
  * Look up the given physical address range in the list of existing ACPI memory
  * mappings.  If found, get a reference to it and return a pointer to it (its
@@ -324,8 +321,8 @@ static void acpi_unmap(acpi_physical_address pg_off, void __iomem *vaddr)
  * During early init (when acpi_permanent_mmap has not been set yet) this
  * routine simply calls __acpi_map_table() to get the job done.
  */
-static void __iomem __ref
-*__acpi_os_map_iomem(acpi_physical_address phys, acpi_size size, bool memory)
+void __iomem __ref
+*acpi_os_map_iomem(acpi_physical_address phys, acpi_size size)
 {
 	struct acpi_ioremap *map;
 	void __iomem *virt;
@@ -356,7 +353,7 @@ static void __iomem __ref
 
 	pg_off = round_down(phys, PAGE_SIZE);
 	pg_sz = round_up(phys + size, PAGE_SIZE) - pg_off;
-	virt = acpi_map(phys, size, memory);
+	virt = acpi_map(phys, size);
 	if (!virt) {
 		mutex_unlock(&acpi_ioremap_lock);
 		kfree(map);
@@ -375,17 +372,11 @@ static void __iomem __ref
 	mutex_unlock(&acpi_ioremap_lock);
 	return map->virt + (phys - map->phys);
 }
-
-void __iomem *__ref
-acpi_os_map_iomem(acpi_physical_address phys, acpi_size size)
-{
-	return __acpi_os_map_iomem(phys, size, false);
-}
 EXPORT_SYMBOL_GPL(acpi_os_map_iomem);
 
 void *__ref acpi_os_map_memory(acpi_physical_address phys, acpi_size size)
 {
-	return (void *)__acpi_os_map_iomem(phys, size, true);
+	return (void *)acpi_os_map_iomem(phys, size);
 }
 EXPORT_SYMBOL_GPL(acpi_os_map_memory);
 
diff --git a/include/acpi/acpi_io.h b/include/acpi/acpi_io.h
index a0212e67d6f44d..027faa8883aab6 100644
--- a/include/acpi/acpi_io.h
+++ b/include/acpi/acpi_io.h
@@ -14,14 +14,6 @@ static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys,
 }
 #endif
 
-#ifndef acpi_os_memmap
-static inline void __iomem *acpi_os_memmap(acpi_physical_address phys,
-					    acpi_size size)
-{
-	return ioremap_cache(phys, size);
-}
-#endif
-
 extern bool acpi_permanent_mmap;
 
 void __iomem __ref