diff --git a/include/linux/pci.h b/include/linux/pci.h
index bb9c367c85f0b6c3cdb0e1f8b5f4b455b3c9f468..bbc2a991b63f6948487135df78e54d6211304a31 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1416,6 +1416,38 @@ pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
 					      NULL);
 }
 
+/**
+ * pci_irqd_intx_xlate() - Translate PCI INTx value to an IRQ domain hwirq
+ * @d: the INTx IRQ domain
+ * @node: the DT node for the device whose interrupt we're translating
+ * @intspec: the interrupt specifier data from the DT
+ * @intsize: the number of entries in @intspec
+ * @out_hwirq: pointer at which to write the hwirq number
+ * @out_type: pointer at which to write the interrupt type
+ *
+ * Translate a PCI INTx interrupt number from device tree in the range 1-4, as
+ * stored in the standard PCI_INTERRUPT_PIN register, to a value in the range
+ * 0-3 suitable for use in a 4 entry IRQ domain. That is, subtract one from the
+ * INTx value to obtain the hwirq number.
+ *
+ * Returns 0 on success, or -EINVAL if the interrupt specifier is out of range.
+ */
+static inline int pci_irqd_intx_xlate(struct irq_domain *d,
+				      struct device_node *node,
+				      const u32 *intspec,
+				      unsigned int intsize,
+				      unsigned long *out_hwirq,
+				      unsigned int *out_type)
+{
+	const u32 intx = intspec[0];
+
+	if (intx < PCI_INTERRUPT_INTA || intx > PCI_INTERRUPT_INTD)
+		return -EINVAL;
+
+	*out_hwirq = intx - PCI_INTERRUPT_INTA;
+	return 0;
+}
+
 #ifdef CONFIG_PCIEPORTBUS
 extern bool pcie_ports_disabled;
 extern bool pcie_ports_auto;