Merge tag 'irq-msi-2025-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull MSI updates from Thomas Gleixner:
 "Updates for [PCI] MSI related code:

   - Remove one variant of PCI/MSI management as all users have been
     converted to use per device domains. That reduces the variants to
     two:

     The modern and the real archaic legacy variant, which keeps the
     usual suspects in the museum category alive.

   - Rework the platform MSI device ID detection mechanism in the ARM
     GIC world to address resource leaks, duplicated code and other
     details. This requires a corresponding preparatory step in the
     PCI/iproc driver.

   - Trivial core code cleanups"

* tag 'irq-msi-2025-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic-its: Rework platform MSI deviceID detection
  PCI: iproc: Implement MSI controller node detection with of_msi_xlate()
  genirq/msi: Slightly simplify msi_domain_alloc()
  PCI/MSI: Delete pci_msi_create_irq_domain()

Author: torvalds

drivers/irqchip/irq-gic-its-msi-parent.c

@@ -142,83 +142,38 @@ static int its_v5_pci_msi_prepare(struct irq_domain *domain, struct device *dev,
 #define its_v5_pci_msi_prepare	NULL
 #endif /* !CONFIG_PCI_MSI */
 
-static int of_pmsi_get_dev_id(struct irq_domain *domain, struct device *dev,
-				  u32 *dev_id)
+static int of_pmsi_get_msi_info(struct irq_domain *domain, struct device *dev, u32 *dev_id,
+				phys_addr_t *pa)
 {
-	int ret, index = 0;
+	struct of_phandle_iterator it;
+	int ret;
 
 	/* Suck the DeviceID out of the msi-parent property */
-	do {
-		struct of_phandle_args args;
-
-		ret = of_parse_phandle_with_args(dev->of_node,
-						 "msi-parent", "#msi-cells",
-						 index, &args);
-		if (args.np == irq_domain_get_of_node(domain)) {
-			if (WARN_ON(args.args_count != 1))
-				return -EINVAL;
-			*dev_id = args.args[0];
-			break;
-		}
-		index++;
-	} while (!ret);
-
-	if (ret) {
-		struct device_node *np = NULL;
+	of_for_each_phandle(&it, ret, dev->of_node, "msi-parent", "#msi-cells", -1) {
+		/* GICv5 ITS domain matches the MSI controller node parent */
+		struct device_node *np __free(device_node) = pa ? of_get_parent(it.node)
+								: of_node_get(it.node);
 
-		ret = of_map_id(dev->of_node, dev->id, "msi-map", "msi-map-mask", &np, dev_id);
-		if (np)
-			of_node_put(np);
-	}
+		if (np == irq_domain_get_of_node(domain)) {
+			u32 args;
 
-	return ret;
-}
+			if (WARN_ON(of_phandle_iterator_args(&it, &args, 1) != 1))
+				ret = -EINVAL;
 
-static int of_v5_pmsi_get_msi_info(struct irq_domain *domain, struct device *dev,
-				   u32 *dev_id, phys_addr_t *pa)
-{
-	int ret, index = 0;
-	/*
-	 * Retrieve the DeviceID and the ITS translate frame node pointer
-	 * out of the msi-parent property.
-	 */
-	do {
-		struct of_phandle_args args;
-
-		ret = of_parse_phandle_with_args(dev->of_node,
-						 "msi-parent", "#msi-cells",
-						 index, &args);
-		if (ret)
-			break;
-		/*
-		 * The IRQ domain fwnode is the msi controller parent
-		 * in GICv5 (where the msi controller nodes are the
-		 * ITS translate frames).
-		 */
-		if (args.np->parent == irq_domain_get_of_node(domain)) {
-			if (WARN_ON(args.args_count != 1))
-				return -EINVAL;
-			*dev_id = args.args[0];
-
-			ret = its_translate_frame_address(args.np, pa);
-			if (ret)
-				return -ENODEV;
-			break;
-		}
-		index++;
-	} while (!ret);
+			if (!ret && pa)
+				ret = its_translate_frame_address(it.node, pa);
 
-	if (ret) {
-		struct device_node *np = NULL;
+			if (!ret)
+				*dev_id = args;
 
-		ret = of_map_id(dev->of_node, dev->id, "msi-map", "msi-map-mask", &np, dev_id);
-		if (np) {
-			ret = its_translate_frame_address(np, pa);
-			of_node_put(np);
+			of_node_put(it.node);
+			return ret;
 		}
 	}
 
-	return ret;
+	struct device_node *msi_ctrl __free(device_node) = NULL;
+
+	return of_map_id(dev->of_node, dev->id, "msi-map", "msi-map-mask", &msi_ctrl, dev_id);
 }
 
 int __weak iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id)
@@ -234,7 +189,7 @@ static int its_pmsi_prepare(struct irq_domain *domain, struct device *dev,
 	int ret;
 
 	if (dev->of_node)
-		ret = of_pmsi_get_dev_id(domain->parent, dev, &dev_id);
+		ret = of_pmsi_get_msi_info(domain->parent, dev, &dev_id, NULL);
 	else
 		ret = iort_pmsi_get_dev_id(dev, &dev_id);
 	if (ret)
@@ -262,7 +217,7 @@ static int its_v5_pmsi_prepare(struct irq_domain *domain, struct device *dev,
 	if (!dev->of_node)
 		return -ENODEV;
 
-	ret = of_v5_pmsi_get_msi_info(domain->parent, dev, &dev_id, &pa);
+	ret = of_pmsi_get_msi_info(domain->parent, dev, &dev_id, &pa);
 	if (ret)
 		return ret;
 

drivers/pci/controller/pcie-iproc.c

@@ -17,6 +17,7 @@
 #include <linux/irqchip/arm-gic-v3.h>
 #include <linux/platform_device.h>
 #include <linux/of_address.h>
+#include <linux/of_irq.h>
 #include <linux/of_pci.h>
 #include <linux/of_platform.h>
 #include <linux/phy/phy.h>
@@ -1337,29 +1338,16 @@ static int iproc_pcie_msi_steer(struct iproc_pcie *pcie,
 
 static int iproc_pcie_msi_enable(struct iproc_pcie *pcie)
 {
-	struct device_node *msi_node;
+	struct device_node *msi_node = NULL;
 	int ret;
 
 	/*
 	 * Either the "msi-parent" or the "msi-map" phandle needs to exist
 	 * for us to obtain the MSI node.
 	 */
-
-	msi_node = of_parse_phandle(pcie->dev->of_node, "msi-parent", 0);
-	if (!msi_node) {
-		const __be32 *msi_map = NULL;
-		int len;
-		u32 phandle;
-
-		msi_map = of_get_property(pcie->dev->of_node, "msi-map", &len);
-		if (!msi_map)
-			return -ENODEV;
-
-		phandle = be32_to_cpup(msi_map + 1);
-		msi_node = of_find_node_by_phandle(phandle);
-		if (!msi_node)
-			return -ENODEV;
-	}
+	of_msi_xlate(pcie->dev, &msi_node, 0);
+	if (!msi_node)
+		return -ENODEV;
 
 	/*
 	 * Certain revisions of the iProc PCIe controller require additional

drivers/pci/msi/irqdomain.c

@@ -49,96 +49,6 @@ static void pci_msi_domain_write_msg(struct irq_data *irq_data, struct msi_msg *
 		__pci_write_msi_msg(desc, msg);
 }
 
-/**
- * pci_msi_domain_calc_hwirq - Generate a unique ID for an MSI source
- * @desc:	Pointer to the MSI descriptor
- *
- * The ID number is only used within the irqdomain.
- */
-static irq_hw_number_t pci_msi_domain_calc_hwirq(struct msi_desc *desc)
-{
-	struct pci_dev *dev = msi_desc_to_pci_dev(desc);
-
-	return (irq_hw_number_t)desc->msi_index |
-		pci_dev_id(dev) << 11 |
-		((irq_hw_number_t)(pci_domain_nr(dev->bus) & 0xFFFFFFFF)) << 27;
-}
-
-static void pci_msi_domain_set_desc(msi_alloc_info_t *arg,
-				    struct msi_desc *desc)
-{
-	arg->desc = desc;
-	arg->hwirq = pci_msi_domain_calc_hwirq(desc);
-}
-
-static struct msi_domain_ops pci_msi_domain_ops_default = {
-	.set_desc	= pci_msi_domain_set_desc,
-};
-
-static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
-{
-	struct msi_domain_ops *ops = info->ops;
-
-	if (ops == NULL) {
-		info->ops = &pci_msi_domain_ops_default;
-	} else {
-		if (ops->set_desc == NULL)
-			ops->set_desc = pci_msi_domain_set_desc;
-	}
-}
-
-static void pci_msi_domain_update_chip_ops(struct msi_domain_info *info)
-{
-	struct irq_chip *chip = info->chip;
-
-	BUG_ON(!chip);
-	if (!chip->irq_write_msi_msg)
-		chip->irq_write_msi_msg = pci_msi_domain_write_msg;
-	if (!chip->irq_mask)
-		chip->irq_mask = pci_msi_mask_irq;
-	if (!chip->irq_unmask)
-		chip->irq_unmask = pci_msi_unmask_irq;
-}
-
-/**
- * pci_msi_create_irq_domain - Create a MSI interrupt domain
- * @fwnode:	Optional fwnode of the interrupt controller
- * @info:	MSI domain info
- * @parent:	Parent irq domain
- *
- * Updates the domain and chip ops and creates a MSI interrupt domain.
- *
- * Returns:
- * A domain pointer or NULL in case of failure.
- */
-struct irq_domain *pci_msi_create_irq_domain(struct fwnode_handle *fwnode,
-					     struct msi_domain_info *info,
-					     struct irq_domain *parent)
-{
-	if (WARN_ON(info->flags & MSI_FLAG_LEVEL_CAPABLE))
-		info->flags &= ~MSI_FLAG_LEVEL_CAPABLE;
-
-	if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS)
-		pci_msi_domain_update_dom_ops(info);
-	if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
-		pci_msi_domain_update_chip_ops(info);
-
-	/* Let the core code free MSI descriptors when freeing interrupts */
-	info->flags |= MSI_FLAG_FREE_MSI_DESCS;
-
-	info->flags |= MSI_FLAG_ACTIVATE_EARLY | MSI_FLAG_DEV_SYSFS;
-	if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE))
-		info->flags |= MSI_FLAG_MUST_REACTIVATE;
-
-	/* PCI-MSI is oneshot-safe */
-	info->chip->flags |= IRQCHIP_ONESHOT_SAFE;
-	/* Let the core update the bus token */
-	info->bus_token = DOMAIN_BUS_PCI_MSI;
-
-	return msi_create_irq_domain(fwnode, info, parent);
-}
-EXPORT_SYMBOL_GPL(pci_msi_create_irq_domain);
-
 /*
  * Per device MSI[-X] domain functionality
  */

include/linux/msi.h

@@ -701,9 +701,6 @@ void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg);
 void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg);
 void pci_msi_mask_irq(struct irq_data *data);
 void pci_msi_unmask_irq(struct irq_data *data);
-struct irq_domain *pci_msi_create_irq_domain(struct fwnode_handle *fwnode,
-					     struct msi_domain_info *info,
-					     struct irq_domain *parent);
 u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev);
 u32 pci_msi_map_rid_ctlr_node(struct pci_dev *pdev, struct device_node **node);
 struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev);

kernel/irq/msi.c

@@ -706,7 +706,7 @@ static int msi_domain_alloc(struct irq_domain *domain, unsigned int virq,
 	irq_hw_number_t hwirq = ops->get_hwirq(info, arg);
 	int i, ret;
 
-	if (irq_find_mapping(domain, hwirq) > 0)
+	if (irq_resolve_mapping(domain, hwirq))
 		return -EEXIST;
 
 	if (domain->parent) {