diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 4f9303f6a6877231bde2380815c033afd955ea5d..9f15539a63428c7d0a2b8cb2edb9c85b1be3feea 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -92,6 +92,9 @@ config MIPS
 	select SYSCTL_EXCEPTION_TRACE
 	select VIRT_TO_BUS
 
+config MIPS_FIXUP_BIGPHYS_ADDR
+	bool
+
 menu "Machine selection"
 
 choice
@@ -157,6 +160,7 @@ config MIPS_ALCHEMY
 	select CSRC_R4K
 	select IRQ_MIPS_CPU
 	select DMA_MAYBE_COHERENT	# Au1000,1500,1100 aren't, rest is
+	select MIPS_FIXUP_BIGPHYS_ADDR if PCI
 	select SYS_HAS_CPU_MIPS32_R1
 	select SYS_SUPPORTS_32BIT_KERNEL
 	select SYS_SUPPORTS_APM_EMULATION
diff --git a/arch/mips/alchemy/common/setup.c b/arch/mips/alchemy/common/setup.c
index 7faaa6d593a74c119cfe6523e4c3e29009b8116a..a8cbc552bd641dcc0ae7de0e0a941f4d1b150e41 100644
--- a/arch/mips/alchemy/common/setup.c
+++ b/arch/mips/alchemy/common/setup.c
@@ -72,9 +72,9 @@ void __init plat_mem_setup(void)
 	iomem_resource.end = IOMEM_RESOURCE_END;
 }
 
-#if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_PCI)
+#ifdef CONFIG_MIPS_FIXUP_BIGPHYS_ADDR
 /* This routine should be valid for all Au1x based boards */
-phys_addr_t __fixup_bigphys_addr(phys_addr_t phys_addr, phys_addr_t size)
+phys_addr_t fixup_bigphys_addr(phys_addr_t phys_addr, phys_addr_t size)
 {
 	unsigned long start = ALCHEMY_PCI_MEMWIN_START;
 	unsigned long end = ALCHEMY_PCI_MEMWIN_END;
@@ -90,5 +90,13 @@ phys_addr_t __fixup_bigphys_addr(phys_addr_t phys_addr, phys_addr_t size)
 	/* default nop */
 	return phys_addr;
 }
-EXPORT_SYMBOL(__fixup_bigphys_addr);
-#endif
+
+int io_remap_pfn_range(struct vm_area_struct *vma, unsigned long vaddr,
+		unsigned long pfn, unsigned long size, pgprot_t prot)
+{
+	phys_addr_t phys_addr = fixup_bigphys_addr(pfn << PAGE_SHIFT, size);
+
+	return remap_pfn_range(vma, vaddr, phys_addr >> PAGE_SHIFT, size, prot);
+}
+EXPORT_SYMBOL(io_remap_pfn_range);
+#endif /* CONFIG_MIPS_FIXUP_BIGPHYS_ADDR */
diff --git a/arch/mips/include/asm/mach-au1x00/ioremap.h b/arch/mips/include/asm/mach-au1x00/ioremap.h
deleted file mode 100644
index f6877ed8b8d090ab1aead336c27c4c08c01db3a3..0000000000000000000000000000000000000000
--- a/arch/mips/include/asm/mach-au1x00/ioremap.h
+++ /dev/null
@@ -1,38 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-/*
- *	include/asm-mips/mach-au1x00/ioremap.h
- */
-#ifndef __ASM_MACH_AU1X00_IOREMAP_H
-#define __ASM_MACH_AU1X00_IOREMAP_H
-
-#include <linux/types.h>
-
-#if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_PCI)
-extern phys_addr_t __fixup_bigphys_addr(phys_addr_t, phys_addr_t);
-#else
-static inline phys_addr_t __fixup_bigphys_addr(phys_addr_t phys_addr, phys_addr_t size)
-{
-	return phys_addr;
-}
-#endif
-
-/*
- * Allow physical addresses to be fixed up to help 36-bit peripherals.
- */
-static inline phys_addr_t fixup_bigphys_addr(phys_addr_t phys_addr, phys_addr_t size)
-{
-	return __fixup_bigphys_addr(phys_addr, size);
-}
-
-static inline void __iomem *plat_ioremap(phys_addr_t offset, unsigned long size,
-	unsigned long flags)
-{
-	return NULL;
-}
-
-static inline int plat_iounmap(const volatile void __iomem *addr)
-{
-	return 0;
-}
-
-#endif /* __ASM_MACH_AU1X00_IOREMAP_H */
diff --git a/arch/mips/include/asm/mach-bcm63xx/ioremap.h b/arch/mips/include/asm/mach-bcm63xx/ioremap.h
index 8cd261ec0a75389e4a652888bbf12aa8d7bf0ca6..73f31825bbf3b5d78cadacea6cb421b0639ba8b6 100644
--- a/arch/mips/include/asm/mach-bcm63xx/ioremap.h
+++ b/arch/mips/include/asm/mach-bcm63xx/ioremap.h
@@ -4,11 +4,6 @@
 
 #include <bcm63xx_cpu.h>
 
-static inline phys_addr_t fixup_bigphys_addr(phys_addr_t phys_addr, phys_addr_t size)
-{
-	return phys_addr;
-}
-
 static inline int is_bcm63xx_internal_registers(phys_addr_t offset)
 {
 	switch (bcm63xx_get_cpu_id()) {
diff --git a/arch/mips/include/asm/mach-bmips/ioremap.h b/arch/mips/include/asm/mach-bmips/ioremap.h
index 52632ebc705f6fa73179a964062e09269729d388..63b4af9916b60440fa65be7108217f97f57796a0 100644
--- a/arch/mips/include/asm/mach-bmips/ioremap.h
+++ b/arch/mips/include/asm/mach-bmips/ioremap.h
@@ -4,11 +4,6 @@
 
 #include <linux/types.h>
 
-static inline phys_addr_t fixup_bigphys_addr(phys_addr_t phys_addr, phys_addr_t size)
-{
-	return phys_addr;
-}
-
 static inline int is_bmips_internal_registers(phys_addr_t offset)
 {
 	if (offset >= 0xfff80000)
diff --git a/arch/mips/include/asm/mach-generic/ioremap.h b/arch/mips/include/asm/mach-generic/ioremap.h
index 4e36ea25ed33c280f4a8e8d0018d626a29ce1f5b..f2442b84545c4c69feb3929deef0149288f4ca94 100644
--- a/arch/mips/include/asm/mach-generic/ioremap.h
+++ b/arch/mips/include/asm/mach-generic/ioremap.h
@@ -7,15 +7,6 @@
 
 #include <linux/types.h>
 
-/*
- * Allow physical addresses to be fixed up to help peripherals located
- * outside the low 32-bit range -- generic pass-through version.
- */
-static inline phys_addr_t fixup_bigphys_addr(phys_addr_t phys_addr, phys_addr_t size)
-{
-	return phys_addr;
-}
-
 static inline void __iomem *plat_ioremap(phys_addr_t offset, unsigned long size,
 	unsigned long flags)
 {
diff --git a/arch/mips/include/asm/mach-tx39xx/ioremap.h b/arch/mips/include/asm/mach-tx39xx/ioremap.h
index 077b3c9971f7187e62b94892facaa71922f4e014..157a7292397ed89c92ec6be6a6b5858da7772d57 100644
--- a/arch/mips/include/asm/mach-tx39xx/ioremap.h
+++ b/arch/mips/include/asm/mach-tx39xx/ioremap.h
@@ -7,15 +7,6 @@
 
 #include <linux/types.h>
 
-/*
- * Allow physical addresses to be fixed up to help peripherals located
- * outside the low 32-bit range -- generic pass-through version.
- */
-static inline phys_addr_t fixup_bigphys_addr(phys_addr_t phys_addr, phys_addr_t size)
-{
-	return phys_addr;
-}
-
 static inline void __iomem *plat_ioremap(phys_addr_t offset, unsigned long size,
 	unsigned long flags)
 {
diff --git a/arch/mips/include/asm/mach-tx49xx/ioremap.h b/arch/mips/include/asm/mach-tx49xx/ioremap.h
index c6b9e05f44c4a694a7a983b8783afe47a3035bb5..b1f3710acf8e139c5248e7b7d5961a0f8dbefbd5 100644
--- a/arch/mips/include/asm/mach-tx49xx/ioremap.h
+++ b/arch/mips/include/asm/mach-tx49xx/ioremap.h
@@ -7,15 +7,6 @@
 
 #include <linux/types.h>
 
-/*
- * Allow physical addresses to be fixed up to help peripherals located
- * outside the low 32-bit range -- generic pass-through version.
- */
-static inline phys_addr_t fixup_bigphys_addr(phys_addr_t phys_addr, phys_addr_t size)
-{
-	return phys_addr;
-}
-
 static inline void __iomem *plat_ioremap(phys_addr_t offset, unsigned long size,
 	unsigned long flags)
 {
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index f1801e7a4b15e753d52f49cc820ac92333eb66ca..aab0ec174f68a118bf9ea8c6ad7972c61f521f51 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -507,20 +507,17 @@ static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
 
 #define kern_addr_valid(addr)	(1)
 
-#ifdef CONFIG_PHYS_ADDR_T_64BIT
-extern int remap_pfn_range(struct vm_area_struct *vma, unsigned long from, unsigned long pfn, unsigned long size, pgprot_t prot);
-
-static inline int io_remap_pfn_range(struct vm_area_struct *vma,
-		unsigned long vaddr,
-		unsigned long pfn,
-		unsigned long size,
-		pgprot_t prot)
-{
-	phys_addr_t phys_addr_high = fixup_bigphys_addr(pfn << PAGE_SHIFT, size);
-	return remap_pfn_range(vma, vaddr, phys_addr_high >> PAGE_SHIFT, size, prot);
-}
+/*
+ * Allow physical addresses to be fixed up to help 36-bit peripherals.
+ */
+#ifdef CONFIG_MIPS_FIXUP_BIGPHYS_ADDR
+phys_addr_t fixup_bigphys_addr(phys_addr_t addr, phys_addr_t size);
+int io_remap_pfn_range(struct vm_area_struct *vma, unsigned long vaddr,
+		unsigned long pfn, unsigned long size, pgprot_t prot);
 #define io_remap_pfn_range io_remap_pfn_range
-#endif
+#else
+#define fixup_bigphys_addr(addr, size)	(addr)
+#endif /* CONFIG_MIPS_FIXUP_BIGPHYS_ADDR */
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 
diff --git a/arch/mips/pci/pci-alchemy.c b/arch/mips/pci/pci-alchemy.c
index 01a2af8215c8d1746748eff19703036ec8674d97..7285b5667568ef1000604ae412e33c5a971bc466 100644
--- a/arch/mips/pci/pci-alchemy.c
+++ b/arch/mips/pci/pci-alchemy.c
@@ -52,7 +52,7 @@ struct alchemy_pci_context {
 static struct alchemy_pci_context *__alchemy_pci_ctx;
 
 
-/* IO/MEM resources for PCI. Keep the memres in sync with __fixup_bigphys_addr
+/* IO/MEM resources for PCI. Keep the memres in sync with fixup_bigphys_addr
  * in arch/mips/alchemy/common/setup.c
  */
 static struct resource alchemy_pci_def_memres = {