v4.19.13 snapshot.
diff --git a/arch/mips/lib/iomap-pci.c b/arch/mips/lib/iomap-pci.c
new file mode 100644
index 0000000..4850509
--- /dev/null
+++ b/arch/mips/lib/iomap-pci.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Implement the default iomap interfaces
+ *
+ * (C) Copyright 2004 Linus Torvalds
+ * (C) Copyright 2006 Ralf Baechle <ralf@linux-mips.org>
+ * (C) Copyright 2007 MIPS Technologies, Inc.
+ * written by Ralf Baechle <ralf@linux-mips.org>
+ */
+#include <linux/pci.h>
+#include <linux/export.h>
+#include <asm/io.h>
+
+#ifdef CONFIG_PCI_DRIVERS_LEGACY
+
+void __iomem *__pci_ioport_map(struct pci_dev *dev,
+ unsigned long port, unsigned int nr)
+{
+ struct pci_controller *ctrl = dev->bus->sysdata;
+ unsigned long base = ctrl->io_map_base;
+
+ /* This will eventually become a BUG_ON but for now be gentle */
+ if (unlikely(!ctrl->io_map_base)) {
+ struct pci_bus *bus = dev->bus;
+ char name[8];
+
+ while (bus->parent)
+ bus = bus->parent;
+
+ ctrl->io_map_base = base = mips_io_port_base;
+
+ sprintf(name, "%04x:%02x", pci_domain_nr(bus), bus->number);
+ printk(KERN_WARNING "io_map_base of root PCI bus %s unset. "
+ "Trying to continue but you better\nfix this issue or "
+ "report it to linux-mips@linux-mips.org or your "
+ "vendor.\n", name);
+#ifdef CONFIG_PCI_DOMAINS
+ panic("To avoid data corruption io_map_base MUST be set with "
+ "multiple PCI domains.");
+#endif
+ }
+
+ return (void __iomem *) (ctrl->io_map_base + port);
+}
+
+#endif /* CONFIG_PCI_DRIVERS_LEGACY */
+
+void pci_iounmap(struct pci_dev *dev, void __iomem * addr)
+{
+ iounmap(addr);
+}
+
+EXPORT_SYMBOL(pci_iounmap);