Merge branch 'pci/controller/msi-parent'

- Use dev_fwnode() instead of of_fwnode_handle() to remove OF dependency
in altera (fixes an unused variable), designware-host, mediatek,
mediatek-gen3, mobiveil, plda, xilinx, xilinx-dma, xilinx-nwl (Jiri
Slaby, Arnd Bergmann)

- Convert aardvark, altera, brcmstb, designware-host, iproc, mediatek,
mediatek-gen3, mobiveil, plda, rcar-host, vmd, xilinx, xilinx-dma,
xilinx-nwl from using pci_msi_create_irq_domain() to using
msi_create_parent_irq_domain() instead; this makes the interrupt
controller per-PCI device, allows dynamic allocation of vectors after
initialization, and allows support of IMS (Nam Cao)

- Convert vmd to using lock guards to tidy the code (Nam Cao)

* pci/controller/msi-parent:
PCI: vmd: Switch to msi_create_parent_irq_domain()
PCI: vmd: Convert to lock guards
PCI: plda: Switch to msi_create_parent_irq_domain()
PCI: xilinx: Switch to msi_create_parent_irq_domain()
PCI: xilinx-nwl: Switch to msi_create_parent_irq_domain()
PCI: xilinx-xdma: Switch to msi_create_parent_irq_domain()
PCI: rcar-host: Switch to msi_create_parent_irq_domain()
PCI: mediatek: Switch to msi_create_parent_irq_domain()
PCI: mediatek-gen3: Switch to msi_create_parent_irq_domain()
PCI: iproc: Switch to msi_create_parent_irq_domain()
PCI: brcmstb: Switch to msi_create_parent_irq_domain()
PCI: altera-msi: Switch to msi_create_parent_irq_domain()
PCI: aardvark: Switch to msi_create_parent_irq_domain()
PCI: mobiveil: Switch to msi_create_parent_irq_domain()
PCI: dwc: Switch to msi_create_parent_irq_domain()
PCI: controller: Use dev_fwnode() instead of of_fwnode_handle()

drivers/pci/controller/Kconfig

···
 	depends on OF
 	depends on PCI_MSI
 	select PCI_BRIDGE_EMUL
+	select IRQ_MSI_LIB
 	help
 	 Add support for Aardvark 64bit PCIe Host Controller. This
 	 controller is part of the South Bridge of the Marvel Armada
···
 	tristate "Altera PCIe MSI feature"
 	depends on PCIE_ALTERA
 	depends on PCI_MSI
+	select IRQ_MSI_LIB
 	help
 	  Say Y here if you want PCIe MSI support for the Altera FPGA.
 	  This MSI driver supports Altera MSI to GIC controller IP.
···
 		   BMIPS_GENERIC || COMPILE_TEST
 	depends on OF
 	depends on PCI_MSI
+	select IRQ_MSI_LIB
 	default ARCH_BRCMSTB || BMIPS_GENERIC
 	help
 	  Say Y here to enable PCIe host controller support for
···
 	bool "Broadcom iProc PCIe MSI support"
 	depends on PCIE_IPROC_PLATFORM || PCIE_IPROC_BCMA
 	depends on PCI_MSI
+	select IRQ_MSI_LIB
 	default ARCH_BCM_IPROC
 	help
 	  Say Y here if you want to enable MSI support for Broadcom's iProc
···
 config VMD
 	depends on PCI_MSI && X86_64 && !UML
 	tristate "Intel Volume Management Device Driver"
+	select IRQ_MSI_LIB
 	help
 	  Adds support for the Intel Volume Management Device (VMD). VMD is a
 	  secondary PCI host bridge that allows PCI Express root ports,
···
 	depends on ARCH_AIROHA || ARCH_MEDIATEK || COMPILE_TEST
 	depends on OF
 	depends on PCI_MSI
+	select IRQ_MSI_LIB
 	help
 	  Say Y here if you want to enable PCIe controller support on
 	  MediaTek SoCs.
···
 	tristate "MediaTek Gen3 PCIe controller"
 	depends on ARCH_AIROHA || ARCH_MEDIATEK || COMPILE_TEST
 	depends on PCI_MSI
+	select IRQ_MSI_LIB
 	help
 	  Adds support for PCIe Gen3 MAC controller for MediaTek SoCs.
 	  This PCIe controller is compatible with Gen3, Gen2 and Gen1 speed,
···
 	bool "Renesas R-Car PCIe controller (host mode)"
 	depends on ARCH_RENESAS || COMPILE_TEST
 	depends on PCI_MSI
+	select IRQ_MSI_LIB
 	help
 	  Say Y here if you want PCIe controller support on R-Car SoCs in host
 	  mode.
···
 	bool "Xilinx AXI PCIe controller"
 	depends on OF
 	depends on PCI_MSI
+	select IRQ_MSI_LIB
 	help
 	  Say 'Y' here if you want kernel to support the Xilinx AXI PCIe
 	  Host Bridge driver.
···
 	depends on ARCH_ZYNQMP || COMPILE_TEST
 	depends on PCI_MSI
 	select PCI_HOST_COMMON
+	select IRQ_MSI_LIB
 	help
 	  Say 'Y' here if you want kernel support for the Xilinx PL DMA
 	  PCIe host bridge. The controller is a Soft IP which can act as
···
 	bool "Xilinx NWL PCIe controller"
 	depends on ARCH_ZYNQMP || COMPILE_TEST
 	depends on PCI_MSI
+	select IRQ_MSI_LIB
 	help
 	 Say 'Y' here if you want kernel support for Xilinx
 	 NWL PCIe controller. The controller can act as Root Port

drivers/pci/controller/dwc/Kconfig

···
 config PCIE_DW_HOST
 	bool
 	select PCIE_DW
+	select IRQ_MSI_LIB
 
 config PCIE_DW_EP
 	bool

drivers/pci/controller/dwc/pcie-designware-host.c

···
 
 #include <linux/iopoll.h>
 #include <linux/irqchip/chained_irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/irqdomain.h>
 #include <linux/msi.h>
 #include <linux/of_address.h>
···
 static struct pci_ops dw_pcie_ops;
 static struct pci_ops dw_child_pcie_ops;
 
-static void dw_msi_ack_irq(struct irq_data *d)
-{
-	irq_chip_ack_parent(d);
-}
+#define DW_PCIE_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS		| \
+				    MSI_FLAG_USE_DEF_CHIP_OPS		| \
+				    MSI_FLAG_NO_AFFINITY		| \
+				    MSI_FLAG_PCI_MSI_MASK_PARENT)
+#define DW_PCIE_MSI_FLAGS_SUPPORTED (MSI_FLAG_MULTI_PCI_MSI		| \
+				     MSI_FLAG_PCI_MSIX			| \
+				     MSI_GENERIC_FLAGS_MASK)
 
-static void dw_msi_mask_irq(struct irq_data *d)
-{
-	pci_msi_mask_irq(d);
-	irq_chip_mask_parent(d);
-}
-
-static void dw_msi_unmask_irq(struct irq_data *d)
-{
-	pci_msi_unmask_irq(d);
-	irq_chip_unmask_parent(d);
-}
-
-static struct irq_chip dw_pcie_msi_irq_chip = {
-	.name = "PCI-MSI",
-	.irq_ack = dw_msi_ack_irq,
-	.irq_mask = dw_msi_mask_irq,
-	.irq_unmask = dw_msi_unmask_irq,
-};
-
-static struct msi_domain_info dw_pcie_msi_domain_info = {
-	.flags	= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		  MSI_FLAG_NO_AFFINITY | MSI_FLAG_PCI_MSIX |
-		  MSI_FLAG_MULTI_PCI_MSI,
-	.chip	= &dw_pcie_msi_irq_chip,
+static const struct msi_parent_ops dw_pcie_msi_parent_ops = {
+	.required_flags		= DW_PCIE_MSI_FLAGS_REQUIRED,
+	.supported_flags	= DW_PCIE_MSI_FLAGS_SUPPORTED,
+	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
+	.chip_flags		= MSI_CHIP_FLAG_SET_ACK,
+	.prefix			= "DW-",
+	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
 };
 
 /* MSI int handler */
···
 int dw_pcie_allocate_domains(struct dw_pcie_rp *pp)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
-	struct fwnode_handle *fwnode = of_fwnode_handle(pci->dev->of_node);
+	struct irq_domain_info info = {
+		.fwnode		= dev_fwnode(pci->dev),
+		.ops		= &dw_pcie_msi_domain_ops,
+		.size		= pp->num_vectors,
+		.host_data	= pp,
+	};
 
-	pp->irq_domain = irq_domain_create_linear(fwnode, pp->num_vectors,
-					       &dw_pcie_msi_domain_ops, pp);
+	pp->irq_domain = msi_create_parent_irq_domain(&info, &dw_pcie_msi_parent_ops);
 	if (!pp->irq_domain) {
 		dev_err(pci->dev, "Failed to create IRQ domain\n");
-		return -ENOMEM;
-	}
-
-	irq_domain_update_bus_token(pp->irq_domain, DOMAIN_BUS_NEXUS);
-
-	pp->msi_domain = pci_msi_create_irq_domain(fwnode,
-						   &dw_pcie_msi_domain_info,
-						   pp->irq_domain);
-	if (!pp->msi_domain) {
-		dev_err(pci->dev, "Failed to create MSI domain\n");
-		irq_domain_remove(pp->irq_domain);
 		return -ENOMEM;
 	}
 
···
 							 NULL, NULL);
 	}
 
-	irq_domain_remove(pp->msi_domain);
 	irq_domain_remove(pp->irq_domain);
 }
 

drivers/pci/controller/dwc/pcie-designware.h

···
 	const struct dw_pcie_host_ops *ops;
 	int			msi_irq[MAX_MSI_CTRLS];
 	struct irq_domain	*irq_domain;
-	struct irq_domain	*msi_domain;
 	dma_addr_t		msi_data;
 	struct irq_chip		*msi_irq_chip;
 	u32			num_vectors;

drivers/pci/controller/mobiveil/Kconfig

···
 config PCIE_MOBIVEIL_HOST
 	bool
 	depends on PCI_MSI
+	select IRQ_MSI_LIB
 	select PCIE_MOBIVEIL
 
 config PCIE_LAYERSCAPE_GEN4

drivers/pci/controller/mobiveil/pcie-mobiveil-host.c

···
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/irqchip/chained_irq.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
···
 	.map = mobiveil_pcie_intx_map,
 };
 
-static struct irq_chip mobiveil_msi_irq_chip = {
-	.name = "Mobiveil PCIe MSI",
-	.irq_mask = pci_msi_mask_irq,
-	.irq_unmask = pci_msi_unmask_irq,
-};
+#define MOBIVEIL_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS		| \
+				     MSI_FLAG_USE_DEF_CHIP_OPS		| \
+				     MSI_FLAG_NO_AFFINITY)
 
-static struct msi_domain_info mobiveil_msi_domain_info = {
-	.flags	= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		  MSI_FLAG_NO_AFFINITY | MSI_FLAG_PCI_MSIX,
-	.chip	= &mobiveil_msi_irq_chip,
+#define MOBIVEIL_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK		| \
+				      MSI_FLAG_PCI_MSIX)
+
+static const struct msi_parent_ops mobiveil_msi_parent_ops = {
+	.required_flags		= MOBIVEIL_MSI_FLAGS_REQUIRED,
+	.supported_flags	= MOBIVEIL_MSI_FLAGS_SUPPORTED,
+	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
+	.prefix			= "Mobiveil-",
+	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
 };
 
 static void mobiveil_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
···
 static int mobiveil_allocate_msi_domains(struct mobiveil_pcie *pcie)
 {
 	struct device *dev = &pcie->pdev->dev;
-	struct fwnode_handle *fwnode = of_fwnode_handle(dev->of_node);
 	struct mobiveil_msi *msi = &pcie->rp.msi;
 
 	mutex_init(&msi->lock);
-	msi->dev_domain = irq_domain_create_linear(NULL, msi->num_of_vectors,
-						   &msi_domain_ops, pcie);
-	if (!msi->dev_domain) {
-		dev_err(dev, "failed to create IRQ domain\n");
-		return -ENOMEM;
-	}
 
-	msi->msi_domain = pci_msi_create_irq_domain(fwnode,
-						    &mobiveil_msi_domain_info,
-						    msi->dev_domain);
-	if (!msi->msi_domain) {
+	struct irq_domain_info info = {
+		.fwnode		= dev_fwnode(dev),
+		.ops		= &msi_domain_ops,
+		.host_data	= pcie,
+		.size		= msi->num_of_vectors,
+	};
+
+	msi->dev_domain = msi_create_parent_irq_domain(&info, &mobiveil_msi_parent_ops);
+	if (!msi->dev_domain) {
 		dev_err(dev, "failed to create MSI domain\n");
-		irq_domain_remove(msi->dev_domain);
 		return -ENOMEM;
 	}
 
···
 	struct mobiveil_root_port *rp = &pcie->rp;
 
 	/* setup INTx */
-	rp->intx_domain = irq_domain_create_linear(of_fwnode_handle(dev->of_node), PCI_NUM_INTX,
-						   &intx_domain_ops, pcie);
-
+	rp->intx_domain = irq_domain_create_linear(dev_fwnode(dev), PCI_NUM_INTX, &intx_domain_ops,
+						   pcie);
 	if (!rp->intx_domain) {
 		dev_err(dev, "Failed to get a INTx IRQ domain\n");
 		return -ENOMEM;

drivers/pci/controller/mobiveil/pcie-mobiveil.h

···
 
 struct mobiveil_msi {			/* MSI information */
 	struct mutex lock;		/* protect bitmap variable */
-	struct irq_domain *msi_domain;
 	struct irq_domain *dev_domain;
 	phys_addr_t msi_pages_phys;
 	int num_of_vectors;

drivers/pci/controller/pci-aardvark.c

···
 #include <linux/gpio/consumer.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
···
 	struct irq_domain *irq_domain;
 	struct irq_chip irq_chip;
 	raw_spinlock_t irq_lock;
-	struct irq_domain *msi_domain;
 	struct irq_domain *msi_inner_domain;
 	raw_spinlock_t msi_irq_lock;
 	DECLARE_BITMAP(msi_used, MSI_IRQ_NUM);
···
 	raw_spin_unlock_irqrestore(&pcie->msi_irq_lock, flags);
 }
 
-static void advk_msi_top_irq_mask(struct irq_data *d)
-{
-	pci_msi_mask_irq(d);
-	irq_chip_mask_parent(d);
-}
-
-static void advk_msi_top_irq_unmask(struct irq_data *d)
-{
-	pci_msi_unmask_irq(d);
-	irq_chip_unmask_parent(d);
-}
-
 static struct irq_chip advk_msi_bottom_irq_chip = {
 	.name			= "MSI",
 	.irq_compose_msi_msg	= advk_msi_irq_compose_msi_msg,
···
 	.xlate = irq_domain_xlate_onecell,
 };
 
-static struct irq_chip advk_msi_irq_chip = {
-	.name		= "advk-MSI",
-	.irq_mask	= advk_msi_top_irq_mask,
-	.irq_unmask	= advk_msi_top_irq_unmask,
-};
+#define ADVK_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS	| \
+				 MSI_FLAG_USE_DEF_CHIP_OPS	| \
+				 MSI_FLAG_PCI_MSI_MASK_PARENT	| \
+				 MSI_FLAG_NO_AFFINITY)
+#define ADVK_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK	| \
+				  MSI_FLAG_PCI_MSIX		| \
+				  MSI_FLAG_MULTI_PCI_MSI)
 
-static struct msi_domain_info advk_msi_domain_info = {
-	.flags	= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		  MSI_FLAG_NO_AFFINITY | MSI_FLAG_MULTI_PCI_MSI |
-		  MSI_FLAG_PCI_MSIX,
-	.chip	= &advk_msi_irq_chip,
+static const struct msi_parent_ops advk_msi_parent_ops = {
+	.required_flags		= ADVK_MSI_FLAGS_REQUIRED,
+	.supported_flags	= ADVK_MSI_FLAGS_SUPPORTED,
+	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
+	.prefix			= "advk-",
+	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
 };
 
 static int advk_pcie_init_msi_irq_domain(struct advk_pcie *pcie)
···
 	raw_spin_lock_init(&pcie->msi_irq_lock);
 	mutex_init(&pcie->msi_used_lock);
 
-	pcie->msi_inner_domain = irq_domain_create_linear(NULL, MSI_IRQ_NUM,
-							  &advk_msi_domain_ops, pcie);
+	struct irq_domain_info info = {
+		.fwnode		= dev_fwnode(dev),
+		.ops		= &advk_msi_domain_ops,
+		.host_data	= pcie,
+		.size		= MSI_IRQ_NUM,
+	};
+
+	pcie->msi_inner_domain = msi_create_parent_irq_domain(&info, &advk_msi_parent_ops);
 	if (!pcie->msi_inner_domain)
 		return -ENOMEM;
-
-	pcie->msi_domain =
-		pci_msi_create_irq_domain(dev_fwnode(dev),
-					  &advk_msi_domain_info,
-					  pcie->msi_inner_domain);
-	if (!pcie->msi_domain) {
-		irq_domain_remove(pcie->msi_inner_domain);
-		return -ENOMEM;
-	}
 
 	return 0;
 }
 
 static void advk_pcie_remove_msi_irq_domain(struct advk_pcie *pcie)
 {
-	irq_domain_remove(pcie->msi_domain);
 	irq_domain_remove(pcie->msi_inner_domain);
 }
 

drivers/pci/controller/pcie-altera-msi.c

···
 
 #include <linux/interrupt.h>
 #include <linux/irqchip/chained_irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/irqdomain.h>
 #include <linux/init.h>
 #include <linux/module.h>
···
 	DECLARE_BITMAP(used, MAX_MSI_VECTORS);
 	struct mutex		lock;	/* protect "used" bitmap */
 	struct platform_device	*pdev;
-	struct irq_domain	*msi_domain;
 	struct irq_domain	*inner_domain;
 	void __iomem		*csr_base;
 	void __iomem		*vector_base;
···
 	chained_irq_exit(chip, desc);
 }
 
-static struct irq_chip altera_msi_irq_chip = {
-	.name = "Altera PCIe MSI",
-	.irq_mask = pci_msi_mask_irq,
-	.irq_unmask = pci_msi_unmask_irq,
-};
+#define ALTERA_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS		| \
+				   MSI_FLAG_USE_DEF_CHIP_OPS		| \
+				   MSI_FLAG_NO_AFFINITY)
 
-static struct msi_domain_info altera_msi_domain_info = {
-	.flags	= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		  MSI_FLAG_NO_AFFINITY | MSI_FLAG_PCI_MSIX,
-	.chip	= &altera_msi_irq_chip,
-};
+#define ALTERA_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK		| \
+				    MSI_FLAG_PCI_MSIX)
 
+static const struct msi_parent_ops altera_msi_parent_ops = {
+	.required_flags		= ALTERA_MSI_FLAGS_REQUIRED,
+	.supported_flags	= ALTERA_MSI_FLAGS_SUPPORTED,
+	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
+	.prefix			= "Altera-",
+	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
+};
 static void altera_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
 {
 	struct altera_msi *msi = irq_data_get_irq_chip_data(data);
···
 
 static int altera_allocate_domains(struct altera_msi *msi)
 {
-	struct fwnode_handle *fwnode = of_fwnode_handle(msi->pdev->dev.of_node);
+	struct irq_domain_info info = {
+		.fwnode		= dev_fwnode(&msi->pdev->dev),
+		.ops		= &msi_domain_ops,
+		.host_data	= msi,
+		.size		= msi->num_of_vectors,
+	};
 
-	msi->inner_domain = irq_domain_create_linear(NULL, msi->num_of_vectors,
-					     &msi_domain_ops, msi);
+	msi->inner_domain = msi_create_parent_irq_domain(&info, &altera_msi_parent_ops);
 	if (!msi->inner_domain) {
-		dev_err(&msi->pdev->dev, "failed to create IRQ domain\n");
-		return -ENOMEM;
-	}
-
-	msi->msi_domain = pci_msi_create_irq_domain(fwnode,
-				&altera_msi_domain_info, msi->inner_domain);
-	if (!msi->msi_domain) {
 		dev_err(&msi->pdev->dev, "failed to create MSI domain\n");
-		irq_domain_remove(msi->inner_domain);
 		return -ENOMEM;
 	}
 
···
 
 static void altera_free_domains(struct altera_msi *msi)
 {
-	irq_domain_remove(msi->msi_domain);
 	irq_domain_remove(msi->inner_domain);
 }
 

drivers/pci/controller/pcie-altera.c

···
 static int altera_pcie_init_irq_domain(struct altera_pcie *pcie)
 {
 	struct device *dev = &pcie->pdev->dev;
-	struct device_node *node = dev->of_node;
 
 	/* Setup INTx */
-	pcie->irq_domain = irq_domain_create_linear(of_fwnode_handle(node), PCI_NUM_INTX,
+	pcie->irq_domain = irq_domain_create_linear(dev_fwnode(dev), PCI_NUM_INTX,
 					&intx_domain_ops, pcie);
 	if (!pcie->irq_domain) {
 		dev_err(dev, "Failed to get a INTx IRQ domain\n");

drivers/pci/controller/pcie-brcmstb.c

···
 #include <linux/iopoll.h>
 #include <linux/ioport.h>
 #include <linux/irqchip/chained_irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
···
 	struct device		*dev;
 	void __iomem		*base;
 	struct device_node	*np;
-	struct irq_domain	*msi_domain;
 	struct irq_domain	*inner_domain;
 	struct mutex		lock; /* guards the alloc/free operations */
 	u64			target_addr;
···
 	writel(tmp, pcie->base + PCIE_MEM_WIN0_LIMIT_HI(win));
 }
 
-static struct irq_chip brcm_msi_irq_chip = {
-	.name            = "BRCM STB PCIe MSI",
-	.irq_ack         = irq_chip_ack_parent,
-	.irq_mask        = pci_msi_mask_irq,
-	.irq_unmask      = pci_msi_unmask_irq,
-};
+#define BRCM_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS	| \
+				 MSI_FLAG_USE_DEF_CHIP_OPS	| \
+				 MSI_FLAG_NO_AFFINITY)
 
-static struct msi_domain_info brcm_msi_domain_info = {
-	.flags	= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		  MSI_FLAG_NO_AFFINITY | MSI_FLAG_MULTI_PCI_MSI,
-	.chip	= &brcm_msi_irq_chip,
+#define BRCM_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK	| \
+				  MSI_FLAG_MULTI_PCI_MSI)
+
+static const struct msi_parent_ops brcm_msi_parent_ops = {
+	.required_flags		= BRCM_MSI_FLAGS_REQUIRED,
+	.supported_flags	= BRCM_MSI_FLAGS_SUPPORTED,
+	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
+	.chip_flags		= MSI_CHIP_FLAG_SET_ACK,
+	.prefix			= "BRCM-",
+	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
 };
 
 static void brcm_pcie_msi_isr(struct irq_desc *desc)
···
 
 static int brcm_allocate_domains(struct brcm_msi *msi)
 {
-	struct fwnode_handle *fwnode = of_fwnode_handle(msi->np);
 	struct device *dev = msi->dev;
 
-	msi->inner_domain = irq_domain_create_linear(NULL, msi->nr, &msi_domain_ops, msi);
-	if (!msi->inner_domain) {
-		dev_err(dev, "failed to create IRQ domain\n");
-		return -ENOMEM;
-	}
+	struct irq_domain_info info = {
+		.fwnode		= of_fwnode_handle(msi->np),
+		.ops		= &msi_domain_ops,
+		.host_data	= msi,
+		.size		= msi->nr,
+	};
 
-	msi->msi_domain = pci_msi_create_irq_domain(fwnode,
-						    &brcm_msi_domain_info,
-						    msi->inner_domain);
-	if (!msi->msi_domain) {
+	msi->inner_domain = msi_create_parent_irq_domain(&info, &brcm_msi_parent_ops);
+	if (!msi->inner_domain) {
 		dev_err(dev, "failed to create MSI domain\n");
-		irq_domain_remove(msi->inner_domain);
 		return -ENOMEM;
 	}
 
···
 
 static void brcm_free_domains(struct brcm_msi *msi)
 {
-	irq_domain_remove(msi->msi_domain);
 	irq_domain_remove(msi->inner_domain);
 }
 

drivers/pci/controller/pcie-iproc-msi.c

···
 
 #include <linux/interrupt.h>
 #include <linux/irqchip/chained_irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/irqdomain.h>
 #include <linux/msi.h>
 #include <linux/of_irq.h>
···
  * @bitmap_lock: lock to protect access to the MSI bitmap
  * @nr_msi_vecs: total number of MSI vectors
  * @inner_domain: inner IRQ domain
- * @msi_domain: MSI IRQ domain
  * @nr_eq_region: required number of 4K aligned memory region for MSI event
  * queues
  * @nr_msi_region: required number of 4K aligned address region for MSI posted
···
 	struct mutex bitmap_lock;
 	unsigned int nr_msi_vecs;
 	struct irq_domain *inner_domain;
-	struct irq_domain *msi_domain;
 	unsigned int nr_eq_region;
 	unsigned int nr_msi_region;
 	void *eq_cpu;
···
 		return eq * EQ_LEN * sizeof(u32);
 }
 
-static struct irq_chip iproc_msi_irq_chip = {
-	.name = "iProc-MSI",
-};
+#define IPROC_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS	| \
+				  MSI_FLAG_USE_DEF_CHIP_OPS)
+#define IPROC_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK	| \
+				   MSI_FLAG_PCI_MSIX)
 
-static struct msi_domain_info iproc_msi_domain_info = {
-	.flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		MSI_FLAG_PCI_MSIX,
-	.chip = &iproc_msi_irq_chip,
+static struct msi_parent_ops iproc_msi_parent_ops = {
+	.required_flags		= IPROC_MSI_FLAGS_REQUIRED,
+	.supported_flags	= IPROC_MSI_FLAGS_SUPPORTED,
+	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
+	.prefix			= "iProc-",
+	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
 };
-
 /*
  * In iProc PCIe core, each MSI group is serviced by a GIC interrupt and a
  * dedicated event queue.  Each MSI group can support up to 64 MSI vectors.
···
 static int iproc_msi_alloc_domains(struct device_node *node,
 				   struct iproc_msi *msi)
 {
-	msi->inner_domain = irq_domain_create_linear(NULL, msi->nr_msi_vecs,
-						     &msi_domain_ops, msi);
+	struct irq_domain_info info = {
+		.fwnode		= of_fwnode_handle(node),
+		.ops		= &msi_domain_ops,
+		.host_data	= msi,
+		.size		= msi->nr_msi_vecs,
+	};
+
+	msi->inner_domain = msi_create_parent_irq_domain(&info, &iproc_msi_parent_ops);
 	if (!msi->inner_domain)
 		return -ENOMEM;
-
-	msi->msi_domain = pci_msi_create_irq_domain(of_fwnode_handle(node),
-						    &iproc_msi_domain_info,
-						    msi->inner_domain);
-	if (!msi->msi_domain) {
-		irq_domain_remove(msi->inner_domain);
-		return -ENOMEM;
-	}
 
 	return 0;
 }
 
 static void iproc_msi_free_domains(struct iproc_msi *msi)
 {
-	if (msi->msi_domain)
-		irq_domain_remove(msi->msi_domain);
-
 	if (msi->inner_domain)
 		irq_domain_remove(msi->inner_domain);
 }
···
 	msi->nr_cpus = num_possible_cpus();
 
 	if (msi->nr_cpus == 1)
-		iproc_msi_domain_info.flags |=  MSI_FLAG_MULTI_PCI_MSI;
+		iproc_msi_parent_ops.supported_flags |= MSI_FLAG_MULTI_PCI_MSI;
 
 	msi->nr_irqs = of_irq_count(node);
 	if (!msi->nr_irqs) {

drivers/pci/controller/pcie-mediatek-gen3.c

···
 #include <linux/delay.h>
 #include <linux/iopoll.h>
 #include <linux/irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/irqchip/chained_irq.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
···
  * @saved_irq_state: IRQ enable state saved at suspend time
  * @irq_lock: lock protecting IRQ register access
  * @intx_domain: legacy INTx IRQ domain
- * @msi_domain: MSI IRQ domain
  * @msi_bottom_domain: MSI IRQ bottom domain
  * @msi_sets: MSI sets information
  * @lock: lock protecting IRQ bit map
···
 	u32 saved_irq_state;
 	raw_spinlock_t irq_lock;
 	struct irq_domain *intx_domain;
-	struct irq_domain *msi_domain;
 	struct irq_domain *msi_bottom_domain;
 	struct mtk_msi_set msi_sets[PCIE_MSI_SET_NUM];
 	struct mutex lock;
···
 	return 0;
 }
 
-static void mtk_pcie_msi_irq_mask(struct irq_data *data)
-{
-	pci_msi_mask_irq(data);
-	irq_chip_mask_parent(data);
-}
+#define MTK_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS	| \
+				MSI_FLAG_USE_DEF_CHIP_OPS	| \
+				MSI_FLAG_NO_AFFINITY		| \
+				MSI_FLAG_PCI_MSI_MASK_PARENT)
 
-static void mtk_pcie_msi_irq_unmask(struct irq_data *data)
-{
-	pci_msi_unmask_irq(data);
-	irq_chip_unmask_parent(data);
-}
+#define MTK_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK		| \
+				 MSI_FLAG_PCI_MSIX		| \
+				 MSI_FLAG_MULTI_PCI_MSI)
 
-static struct irq_chip mtk_msi_irq_chip = {
-	.irq_ack = irq_chip_ack_parent,
-	.irq_mask = mtk_pcie_msi_irq_mask,
-	.irq_unmask = mtk_pcie_msi_irq_unmask,
-	.name = "MSI",
-};
-
-static struct msi_domain_info mtk_msi_domain_info = {
-	.flags	= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		  MSI_FLAG_NO_AFFINITY | MSI_FLAG_PCI_MSIX |
-		  MSI_FLAG_MULTI_PCI_MSI,
-	.chip	= &mtk_msi_irq_chip,
+static const struct msi_parent_ops mtk_msi_parent_ops = {
+	.required_flags		= MTK_MSI_FLAGS_REQUIRED,
+	.supported_flags	= MTK_MSI_FLAGS_SUPPORTED,
+	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
+	.chip_flags		= MSI_CHIP_FLAG_SET_ACK,
+	.prefix			= "MTK3-",
+	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
 };
 
 static void mtk_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
···
 	/* Setup MSI */
 	mutex_init(&pcie->lock);
 
-	pcie->msi_bottom_domain = irq_domain_create_linear(of_fwnode_handle(node),
-							   PCIE_MSI_IRQS_NUM,
-							   &mtk_msi_bottom_domain_ops, pcie);
+	struct irq_domain_info info = {
+		.fwnode		= dev_fwnode(dev),
+		.ops		= &mtk_msi_bottom_domain_ops,
+		.host_data	= pcie,
+		.size		= PCIE_MSI_IRQS_NUM,
+	};
+
+	pcie->msi_bottom_domain = msi_create_parent_irq_domain(&info, &mtk_msi_parent_ops);
 	if (!pcie->msi_bottom_domain) {
 		dev_err(dev, "failed to create MSI bottom domain\n");
 		ret = -ENODEV;
 		goto err_msi_bottom_domain;
 	}
 
-	pcie->msi_domain = pci_msi_create_irq_domain(dev->fwnode,
-						     &mtk_msi_domain_info,
-						     pcie->msi_bottom_domain);
-	if (!pcie->msi_domain) {
-		dev_err(dev, "failed to create MSI domain\n");
-		ret = -ENODEV;
-		goto err_msi_domain;
-	}
-
 	of_node_put(intc_node);
 	return 0;
 
-err_msi_domain:
-	irq_domain_remove(pcie->msi_bottom_domain);
 err_msi_bottom_domain:
 	irq_domain_remove(pcie->intx_domain);
 out_put_node:
···
 
 	if (pcie->intx_domain)
 		irq_domain_remove(pcie->intx_domain);
-
-	if (pcie->msi_domain)
-		irq_domain_remove(pcie->msi_domain);
 
 	if (pcie->msi_bottom_domain)
 		irq_domain_remove(pcie->msi_bottom_domain);

drivers/pci/controller/pcie-mediatek.c

···
 #include <linux/iopoll.h>
 #include <linux/irq.h>
 #include <linux/irqchip/chained_irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
 #include <linux/mfd/syscon.h>
···
  * @irq: GIC irq
  * @irq_domain: legacy INTx IRQ domain
  * @inner_domain: inner IRQ domain
- * @msi_domain: MSI IRQ domain
  * @lock: protect the msi_irq_in_use bitmap
  * @msi_irq_in_use: bit map for assigned MSI IRQ
  */
···
 	int irq;
 	struct irq_domain *irq_domain;
 	struct irq_domain *inner_domain;
-	struct irq_domain *msi_domain;
 	struct mutex lock;
 	DECLARE_BITMAP(msi_irq_in_use, MTK_MSI_IRQS_NUM);
 };
···
 	.free	= mtk_pcie_irq_domain_free,
 };
 
-static struct irq_chip mtk_msi_irq_chip = {
-	.name		= "MTK PCIe MSI",
-	.irq_ack	= irq_chip_ack_parent,
-	.irq_mask	= pci_msi_mask_irq,
-	.irq_unmask	= pci_msi_unmask_irq,
-};
+#define MTK_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS	| \
+				MSI_FLAG_USE_DEF_CHIP_OPS	| \
+				MSI_FLAG_NO_AFFINITY)
 
-static struct msi_domain_info mtk_msi_domain_info = {
-	.flags	= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		  MSI_FLAG_NO_AFFINITY | MSI_FLAG_PCI_MSIX,
-	.chip	= &mtk_msi_irq_chip,
+#define MTK_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK		| \
+				 MSI_FLAG_PCI_MSIX)
+
+static const struct msi_parent_ops mtk_msi_parent_ops = {
+	.required_flags		= MTK_MSI_FLAGS_REQUIRED,
+	.supported_flags	= MTK_MSI_FLAGS_SUPPORTED,
+	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
+	.chip_flags		= MSI_CHIP_FLAG_SET_ACK,
+	.prefix			= "MTK-",
+	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
 };
 
 static int mtk_pcie_allocate_msi_domains(struct mtk_pcie_port *port)
 {
-	struct fwnode_handle *fwnode = of_fwnode_handle(port->pcie->dev->of_node);
-
 	mutex_init(&port->lock);
 
-	port->inner_domain = irq_domain_create_linear(fwnode, MTK_MSI_IRQS_NUM,
-						      &msi_domain_ops, port);
+	struct irq_domain_info info = {
+		.fwnode		= dev_fwnode(port->pcie->dev),
+		.ops		= &msi_domain_ops,
+		.host_data	= port,
+		.size		= MTK_MSI_IRQS_NUM,
+	};
+
+	port->inner_domain = msi_create_parent_irq_domain(&info, &mtk_msi_parent_ops);
 	if (!port->inner_domain) {
 		dev_err(port->pcie->dev, "failed to create IRQ domain\n");
-		return -ENOMEM;
-	}
-
-	port->msi_domain = pci_msi_create_irq_domain(fwnode, &mtk_msi_domain_info,
-						     port->inner_domain);
-	if (!port->msi_domain) {
-		dev_err(port->pcie->dev, "failed to create MSI domain\n");
-		irq_domain_remove(port->inner_domain);
 		return -ENOMEM;
 	}
 
···
 			irq_domain_remove(port->irq_domain);
 
 		if (IS_ENABLED(CONFIG_PCI_MSI)) {
-			if (port->msi_domain)
-				irq_domain_remove(port->msi_domain);
 			if (port->inner_domain)
 				irq_domain_remove(port->inner_domain);
 		}

drivers/pci/controller/pcie-rcar-host.c

···
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
···
 	return IRQ_HANDLED;
 }
 
-static void rcar_msi_top_irq_ack(struct irq_data *d)
-{
-	irq_chip_ack_parent(d);
-}
-
-static void rcar_msi_top_irq_mask(struct irq_data *d)
-{
-	pci_msi_mask_irq(d);
-	irq_chip_mask_parent(d);
-}
-
-static void rcar_msi_top_irq_unmask(struct irq_data *d)
-{
-	pci_msi_unmask_irq(d);
-	irq_chip_unmask_parent(d);
-}
-
-static struct irq_chip rcar_msi_top_chip = {
-	.name		= "PCIe MSI",
-	.irq_ack	= rcar_msi_top_irq_ack,
-	.irq_mask	= rcar_msi_top_irq_mask,
-	.irq_unmask	= rcar_msi_top_irq_unmask,
-};
-
 static void rcar_msi_irq_ack(struct irq_data *d)
 {
 	struct rcar_msi *msi = irq_data_get_irq_chip_data(d);
···
 	.free	= rcar_msi_domain_free,
 };
 
-static struct msi_domain_info rcar_msi_info = {
-	.flags	= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		  MSI_FLAG_NO_AFFINITY | MSI_FLAG_MULTI_PCI_MSI,
-	.chip	= &rcar_msi_top_chip,
+#define RCAR_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS	| \
+				 MSI_FLAG_USE_DEF_CHIP_OPS	| \
+				 MSI_FLAG_PCI_MSI_MASK_PARENT	| \
+				 MSI_FLAG_NO_AFFINITY)
+
+#define RCAR_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK	| \
+				  MSI_FLAG_MULTI_PCI_MSI)
+
+static const struct msi_parent_ops rcar_msi_parent_ops = {
+	.required_flags		= RCAR_MSI_FLAGS_REQUIRED,
+	.supported_flags	= RCAR_MSI_FLAGS_SUPPORTED,
+	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
+	.chip_flags		= MSI_CHIP_FLAG_SET_ACK,
+	.prefix			= "RCAR-",
+	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
 };
 
 static int rcar_allocate_domains(struct rcar_msi *msi)
 {
 	struct rcar_pcie *pcie = &msi_to_host(msi)->pcie;
-	struct fwnode_handle *fwnode = dev_fwnode(pcie->dev);
-	struct irq_domain *parent;
+	struct irq_domain_info info = {
+		.fwnode		= dev_fwnode(pcie->dev),
+		.ops		= &rcar_msi_domain_ops,
+		.host_data	= msi,
+		.size		= INT_PCI_MSI_NR,
+	};
 
-	parent = irq_domain_create_linear(fwnode, INT_PCI_MSI_NR,
-					  &rcar_msi_domain_ops, msi);
-	if (!parent) {
-		dev_err(pcie->dev, "failed to create IRQ domain\n");
-		return -ENOMEM;
-	}
-	irq_domain_update_bus_token(parent, DOMAIN_BUS_NEXUS);
-
-	msi->domain = pci_msi_create_irq_domain(fwnode, &rcar_msi_info, parent);
+	msi->domain = msi_create_parent_irq_domain(&info, &rcar_msi_parent_ops);
 	if (!msi->domain) {
-		dev_err(pcie->dev, "failed to create MSI domain\n");
-		irq_domain_remove(parent);
+		dev_err(pcie->dev, "failed to create IRQ domain\n");
 		return -ENOMEM;
 	}
 
···
 
 static void rcar_free_domains(struct rcar_msi *msi)
 {
-	struct irq_domain *parent = msi->domain->parent;
-
 	irq_domain_remove(msi->domain);
-	irq_domain_remove(parent);
 }
 
 static int rcar_pcie_enable_msi(struct rcar_pcie_host *host)

drivers/pci/controller/pcie-xilinx-dma-pl.c

···
 #include <linux/bitfield.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
···
 };
 
 struct xilinx_msi {
-	struct irq_domain	*msi_domain;
 	unsigned long		*bitmap;
 	struct irq_domain	*dev_domain;
 	struct mutex		lock;		/* Protect bitmap variable */
···
 	return IRQ_HANDLED;
 }
 
-static struct irq_chip xilinx_msi_irq_chip = {
-	.name = "pl_dma:PCIe MSI",
-	.irq_enable = pci_msi_unmask_irq,
-	.irq_disable = pci_msi_mask_irq,
-	.irq_mask = pci_msi_mask_irq,
-	.irq_unmask = pci_msi_unmask_irq,
-};
+#define XILINX_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS	| \
+				   MSI_FLAG_USE_DEF_CHIP_OPS	| \
+				   MSI_FLAG_NO_AFFINITY)
 
-static struct msi_domain_info xilinx_msi_domain_info = {
-	.flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		 MSI_FLAG_NO_AFFINITY | MSI_FLAG_MULTI_PCI_MSI,
-	.chip = &xilinx_msi_irq_chip,
-};
+#define XILINX_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK	| \
+				    MSI_FLAG_MULTI_PCI_MSI)
 
+static const struct msi_parent_ops xilinx_msi_parent_ops = {
+	.required_flags		= XILINX_MSI_FLAGS_REQUIRED,
+	.supported_flags	= XILINX_MSI_FLAGS_SUPPORTED,
+	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
+	.prefix			= "pl_dma-",
+	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
+};
 static void xilinx_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
 {
 	struct pl_dma_pcie *pcie = irq_data_get_irq_chip_data(data);
···
 		irq_domain_remove(msi->dev_domain);
 		msi->dev_domain = NULL;
 	}
-
-	if (msi->msi_domain) {
-		irq_domain_remove(msi->msi_domain);
-		msi->msi_domain = NULL;
-	}
 }
 
 static int xilinx_pl_dma_pcie_init_msi_irq_domain(struct pl_dma_pcie *port)
···
 	struct device *dev = port->dev;
 	struct xilinx_msi *msi = &port->msi;
 	int size = BITS_TO_LONGS(XILINX_NUM_MSI_IRQS) * sizeof(long);
-	struct fwnode_handle *fwnode = of_fwnode_handle(port->dev->of_node);
+	struct irq_domain_info info = {
+		.fwnode		= dev_fwnode(port->dev),
+		.ops		= &dev_msi_domain_ops,
+		.host_data	= port,
+		.size		= XILINX_NUM_MSI_IRQS,
+	};
 
-	msi->dev_domain = irq_domain_create_linear(NULL, XILINX_NUM_MSI_IRQS,
-						   &dev_msi_domain_ops, port);
+	msi->dev_domain  = msi_create_parent_irq_domain(&info, &xilinx_msi_parent_ops);
 	if (!msi->dev_domain)
-		goto out;
-
-	msi->msi_domain = pci_msi_create_irq_domain(fwnode,
-						    &xilinx_msi_domain_info,
-						    msi->dev_domain);
-	if (!msi->msi_domain)
 		goto out;
 
 	mutex_init(&msi->lock);

drivers/pci/controller/pcie-xilinx-nwl.c

···
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
···
 #define LINK_WAIT_USLEEP_MAX           100000
 
 struct nwl_msi {			/* MSI information */
-	struct irq_domain *msi_domain;
 	DECLARE_BITMAP(bitmap, INT_PCI_MSI_NR);
 	struct irq_domain *dev_domain;
 	struct mutex lock;		/* protect bitmap variable */
···
 };
 
 #ifdef CONFIG_PCI_MSI
-static struct irq_chip nwl_msi_irq_chip = {
-	.name = "nwl_pcie:msi",
-	.irq_enable = pci_msi_unmask_irq,
-	.irq_disable = pci_msi_mask_irq,
-	.irq_mask = pci_msi_mask_irq,
-	.irq_unmask = pci_msi_unmask_irq,
+
+#define NWL_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS	| \
+				MSI_FLAG_USE_DEF_CHIP_OPS	| \
+				MSI_FLAG_NO_AFFINITY)
+
+#define NWL_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK		| \
+				 MSI_FLAG_MULTI_PCI_MSI)
+
+static const struct msi_parent_ops nwl_msi_parent_ops = {
+	.required_flags		= NWL_MSI_FLAGS_REQUIRED,
+	.supported_flags	= NWL_MSI_FLAGS_SUPPORTED,
+	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
+	.prefix			= "nwl-",
+	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
 };
 
-static struct msi_domain_info nwl_msi_domain_info = {
-	.flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		 MSI_FLAG_NO_AFFINITY | MSI_FLAG_MULTI_PCI_MSI,
-	.chip = &nwl_msi_irq_chip,
-};
 #endif
 
 static void nwl_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
···
 {
 #ifdef CONFIG_PCI_MSI
 	struct device *dev = pcie->dev;
-	struct fwnode_handle *fwnode = of_fwnode_handle(dev->of_node);
 	struct nwl_msi *msi = &pcie->msi;
+	struct irq_domain_info info = {
+		.fwnode		= dev_fwnode(dev),
+		.ops		= &dev_msi_domain_ops,
+		.host_data	= pcie,
+		.size		= INT_PCI_MSI_NR,
+	};
 
-	msi->dev_domain = irq_domain_create_linear(NULL, INT_PCI_MSI_NR, &dev_msi_domain_ops, pcie);
+	msi->dev_domain  = msi_create_parent_irq_domain(&info, &nwl_msi_parent_ops);
 	if (!msi->dev_domain) {
 		dev_err(dev, "failed to create dev IRQ domain\n");
-		return -ENOMEM;
-	}
-	msi->msi_domain = pci_msi_create_irq_domain(fwnode,
-						    &nwl_msi_domain_info,
-						    msi->dev_domain);
-	if (!msi->msi_domain) {
-		dev_err(dev, "failed to create msi IRQ domain\n");
-		irq_domain_remove(msi->dev_domain);
 		return -ENOMEM;
 	}
 #endif

drivers/pci/controller/pcie-xilinx.c

···
 
 #include <linux/interrupt.h>
 #include <linux/irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
···
 	 */
 }
 
-static struct irq_chip xilinx_msi_top_chip = {
-	.name		= "PCIe MSI",
-	.irq_ack	= xilinx_msi_top_irq_ack,
-};
-
 static void xilinx_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
 {
 	struct xilinx_pcie *pcie = irq_data_get_irq_chip_data(data);
···
 	.free	= xilinx_msi_domain_free,
 };
 
-static struct msi_domain_info xilinx_msi_info = {
-	.flags	= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		  MSI_FLAG_NO_AFFINITY,
-	.chip	= &xilinx_msi_top_chip,
+static bool xilinx_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
+				     struct irq_domain *real_parent, struct msi_domain_info *info)
+{
+	struct irq_chip *chip = info->chip;
+
+	if (!msi_lib_init_dev_msi_info(dev, domain, real_parent, info))
+		return false;
+
+	chip->irq_ack = xilinx_msi_top_irq_ack;
+	return true;
+}
+
+#define XILINX_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS	| \
+				   MSI_FLAG_USE_DEF_CHIP_OPS	| \
+				   MSI_FLAG_NO_AFFINITY)
+
+static const struct msi_parent_ops xilinx_msi_parent_ops = {
+	.required_flags		= XILINX_MSI_FLAGS_REQUIRED,
+	.supported_flags	= MSI_GENERIC_FLAGS_MASK,
+	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
+	.prefix			= "xilinx-",
+	.init_dev_msi_info	= xilinx_init_dev_msi_info,
 };
 
 static int xilinx_allocate_msi_domains(struct xilinx_pcie *pcie)
 {
-	struct fwnode_handle *fwnode = dev_fwnode(pcie->dev);
-	struct irq_domain *parent;
+	struct irq_domain_info info = {
+		.fwnode		= dev_fwnode(pcie->dev),
+		.ops		= &xilinx_msi_domain_ops,
+		.host_data	= pcie,
+		.size		= XILINX_NUM_MSI_IRQS,
+	};
 
-	parent = irq_domain_create_linear(fwnode, XILINX_NUM_MSI_IRQS,
-					  &xilinx_msi_domain_ops, pcie);
-	if (!parent) {
-		dev_err(pcie->dev, "failed to create IRQ domain\n");
-		return -ENOMEM;
-	}
-	irq_domain_update_bus_token(parent, DOMAIN_BUS_NEXUS);
-
-	pcie->msi_domain = pci_msi_create_irq_domain(fwnode, &xilinx_msi_info, parent);
+	pcie->msi_domain = msi_create_parent_irq_domain(&info, &xilinx_msi_parent_ops);
 	if (!pcie->msi_domain) {
 		dev_err(pcie->dev, "failed to create MSI domain\n");
-		irq_domain_remove(parent);
 		return -ENOMEM;
 	}
 
···
 
 static void xilinx_free_msi_domains(struct xilinx_pcie *pcie)
 {
-	struct irq_domain *parent = pcie->msi_domain->parent;
-
 	irq_domain_remove(pcie->msi_domain);
-	irq_domain_remove(parent);
 }
 
 /* INTx Functions */

drivers/pci/controller/plda/Kconfig

···
 
 config PCIE_PLDA_HOST
 	bool
+	select IRQ_MSI_LIB
 
 config PCIE_MICROCHIP_HOST
 	tristate "Microchip AXI PCIe controller"

drivers/pci/controller/plda/pcie-plda-host.c

···
 #include <linux/align.h>
 #include <linux/bitfield.h>
 #include <linux/irqchip/chained_irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/irqdomain.h>
 #include <linux/msi.h>
 #include <linux/pci_regs.h>
···
 	.free	= plda_irq_msi_domain_free,
 };
 
-static struct irq_chip plda_msi_irq_chip = {
-	.name = "PLDA PCIe MSI",
-	.irq_ack = irq_chip_ack_parent,
-	.irq_mask = pci_msi_mask_irq,
-	.irq_unmask = pci_msi_unmask_irq,
-};
+#define PLDA_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS	| \
+				 MSI_FLAG_USE_DEF_CHIP_OPS	| \
+				 MSI_FLAG_NO_AFFINITY)
+#define PLDA_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK	| \
+				  MSI_FLAG_PCI_MSIX)
 
-static struct msi_domain_info plda_msi_domain_info = {
-	.flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-		 MSI_FLAG_NO_AFFINITY | MSI_FLAG_PCI_MSIX,
-	.chip = &plda_msi_irq_chip,
+static const struct msi_parent_ops plda_msi_parent_ops = {
+	.required_flags		= PLDA_MSI_FLAGS_REQUIRED,
+	.supported_flags	= PLDA_MSI_FLAGS_SUPPORTED,
+	.chip_flags		= MSI_CHIP_FLAG_SET_ACK,
+	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
+	.prefix			= "PLDA-",
+	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
 };
 
 static int plda_allocate_msi_domains(struct plda_pcie_rp *port)
 {
 	struct device *dev = port->dev;
-	struct fwnode_handle *fwnode = of_fwnode_handle(dev->of_node);
 	struct plda_msi *msi = &port->msi;
 
 	mutex_init(&port->msi.lock);
 
-	msi->dev_domain = irq_domain_create_linear(NULL, msi->num_vectors, &msi_domain_ops, port);
+	struct irq_domain_info info = {
+		.fwnode		= dev_fwnode(dev),
+		.ops		= &msi_domain_ops,
+		.host_data	= port,
+		.size		= msi->num_vectors,
+	};
+
+	msi->dev_domain = msi_create_parent_irq_domain(&info, &plda_msi_parent_ops);
 	if (!msi->dev_domain) {
 		dev_err(dev, "failed to create IRQ domain\n");
-		return -ENOMEM;
-	}
-
-	msi->msi_domain = pci_msi_create_irq_domain(fwnode,
-						    &plda_msi_domain_info,
-						    msi->dev_domain);
-	if (!msi->msi_domain) {
-		dev_err(dev, "failed to create MSI domain\n");
-		irq_domain_remove(msi->dev_domain);
 		return -ENOMEM;
 	}
 
···
 	irq_set_chained_handler_and_data(pcie->msi_irq, NULL, NULL);
 	irq_set_chained_handler_and_data(pcie->intx_irq, NULL, NULL);
 
-	irq_domain_remove(pcie->msi.msi_domain);
 	irq_domain_remove(pcie->msi.dev_domain);
 
 	irq_domain_remove(pcie->intx_domain);

drivers/pci/controller/plda/pcie-plda.h

···
 
 struct plda_msi {
 	struct mutex lock;		/* Protect used bitmap */
-	struct irq_domain *msi_domain;
 	struct irq_domain *dev_domain;
 	u32 num_vectors;
 	u64 vector_phy;

drivers/pci/controller/vmd.c

···
 #include <linux/device.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
+#include <linux/irqchip/irq-msi-lib.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/msi.h>
···
 	msg->arch_addr_lo.destid_0_7 = index_from_irqs(vmd, irq);
 }
 
-/*
- * We rely on MSI_FLAG_USE_DEF_CHIP_OPS to set the IRQ mask/unmask ops.
- */
 static void vmd_irq_enable(struct irq_data *data)
 {
 	struct vmd_irq *vmdirq = data->chip_data;
-	unsigned long flags;
 
-	raw_spin_lock_irqsave(&list_lock, flags);
-	WARN_ON(vmdirq->enabled);
-	list_add_tail_rcu(&vmdirq->node, &vmdirq->irq->irq_list);
-	vmdirq->enabled = true;
-	raw_spin_unlock_irqrestore(&list_lock, flags);
+	scoped_guard(raw_spinlock_irqsave, &list_lock) {
+		WARN_ON(vmdirq->enabled);
+		list_add_tail_rcu(&vmdirq->node, &vmdirq->irq->irq_list);
+		vmdirq->enabled = true;
+	}
+}
 
+static void vmd_pci_msi_enable(struct irq_data *data)
+{
+	vmd_irq_enable(data->parent_data);
 	data->chip->irq_unmask(data);
 }
 
 static void vmd_irq_disable(struct irq_data *data)
 {
 	struct vmd_irq *vmdirq = data->chip_data;
-	unsigned long flags;
 
-	data->chip->irq_mask(data);
-
-	raw_spin_lock_irqsave(&list_lock, flags);
-	if (vmdirq->enabled) {
-		list_del_rcu(&vmdirq->node);
-		vmdirq->enabled = false;
+	scoped_guard(raw_spinlock_irqsave, &list_lock) {
+		if (vmdirq->enabled) {
+			list_del_rcu(&vmdirq->node);
+			vmdirq->enabled = false;
+		}
 	}
-	raw_spin_unlock_irqrestore(&list_lock, flags);
+}
+
+static void vmd_pci_msi_disable(struct irq_data *data)
+{
+	data->chip->irq_mask(data);
+	vmd_irq_disable(data->parent_data);
 }
 
 static struct irq_chip vmd_msi_controller = {
 	.name			= "VMD-MSI",
-	.irq_enable		= vmd_irq_enable,
-	.irq_disable		= vmd_irq_disable,
 	.irq_compose_msi_msg	= vmd_compose_msi_msg,
 };
-
-static irq_hw_number_t vmd_get_hwirq(struct msi_domain_info *info,
-				     msi_alloc_info_t *arg)
-{
-	return 0;
-}
 
 /*
  * XXX: We can be even smarter selecting the best IRQ once we solve the
···
  */
 static struct vmd_irq_list *vmd_next_irq(struct vmd_dev *vmd, struct msi_desc *desc)
 {
-	unsigned long flags;
 	int i, best;
 
 	if (vmd->msix_count == 1 + vmd->first_vec)
···
 		return &vmd->irqs[vmd->first_vec];
 	}
 
-	raw_spin_lock_irqsave(&list_lock, flags);
-	best = vmd->first_vec + 1;
-	for (i = best; i < vmd->msix_count; i++)
-		if (vmd->irqs[i].count < vmd->irqs[best].count)
-			best = i;
-	vmd->irqs[best].count++;
-	raw_spin_unlock_irqrestore(&list_lock, flags);
+	scoped_guard(raw_spinlock_irq, &list_lock) {
+		best = vmd->first_vec + 1;
+		for (i = best; i < vmd->msix_count; i++)
+			if (vmd->irqs[i].count < vmd->irqs[best].count)
+				best = i;
+		vmd->irqs[best].count++;
+	}
 
 	return &vmd->irqs[best];
 }
 
-static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
-			unsigned int virq, irq_hw_number_t hwirq,
-			msi_alloc_info_t *arg)
+static void vmd_msi_free(struct irq_domain *domain, unsigned int virq,
+			 unsigned int nr_irqs);
+
+static int vmd_msi_alloc(struct irq_domain *domain, unsigned int virq,
+			 unsigned int nr_irqs, void *arg)
 {
-	struct msi_desc *desc = arg->desc;
-	struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus);
-	struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);
+	struct msi_desc *desc = ((msi_alloc_info_t *)arg)->desc;
+	struct vmd_dev *vmd = domain->host_data;
+	struct vmd_irq *vmdirq;
 
-	if (!vmdirq)
-		return -ENOMEM;
+	for (int i = 0; i < nr_irqs; ++i) {
+		vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);
+		if (!vmdirq) {
+			vmd_msi_free(domain, virq, i);
+			return -ENOMEM;
+		}
 
-	INIT_LIST_HEAD(&vmdirq->node);
-	vmdirq->irq = vmd_next_irq(vmd, desc);
-	vmdirq->virq = virq;
+		INIT_LIST_HEAD(&vmdirq->node);
+		vmdirq->irq = vmd_next_irq(vmd, desc);
+		vmdirq->virq = virq + i;
 
-	irq_domain_set_info(domain, virq, vmdirq->irq->virq, info->chip, vmdirq,
-			    handle_untracked_irq, vmd, NULL);
+		irq_domain_set_info(domain, virq + i, vmdirq->irq->virq,
+				    &vmd_msi_controller, vmdirq,
+				    handle_untracked_irq, vmd, NULL);
+	}
+
 	return 0;
 }
 
-static void vmd_msi_free(struct irq_domain *domain,
-			struct msi_domain_info *info, unsigned int virq)
+static void vmd_msi_free(struct irq_domain *domain, unsigned int virq,
+			 unsigned int nr_irqs)
 {
-	struct vmd_irq *vmdirq = irq_get_chip_data(virq);
-	unsigned long flags;
+	struct vmd_irq *vmdirq;
 
-	synchronize_srcu(&vmdirq->irq->srcu);
+	for (int i = 0; i < nr_irqs; ++i) {
+		vmdirq = irq_get_chip_data(virq + i);
 
-	/* XXX: Potential optimization to rebalance */
-	raw_spin_lock_irqsave(&list_lock, flags);
-	vmdirq->irq->count--;
-	raw_spin_unlock_irqrestore(&list_lock, flags);
+		synchronize_srcu(&vmdirq->irq->srcu);
 
-	kfree(vmdirq);
+		/* XXX: Potential optimization to rebalance */
+		scoped_guard(raw_spinlock_irq, &list_lock)
+			vmdirq->irq->count--;
+
+		kfree(vmdirq);
+	}
 }
 
-static int vmd_msi_prepare(struct irq_domain *domain, struct device *dev,
-			   int nvec, msi_alloc_info_t *arg)
+static const struct irq_domain_ops vmd_msi_domain_ops = {
+	.alloc		= vmd_msi_alloc,
+	.free		= vmd_msi_free,
+};
+
+static bool vmd_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
+				  struct irq_domain *real_parent,
+				  struct msi_domain_info *info)
 {
-	struct pci_dev *pdev = to_pci_dev(dev);
-	struct vmd_dev *vmd = vmd_from_bus(pdev->bus);
+	if (WARN_ON_ONCE(info->bus_token != DOMAIN_BUS_PCI_DEVICE_MSIX))
+		return false;
 
-	if (nvec > vmd->msix_count)
-		return vmd->msix_count;
+	if (!msi_lib_init_dev_msi_info(dev, domain, real_parent, info))
+		return false;
 
-	memset(arg, 0, sizeof(*arg));
+	info->chip->irq_enable		= vmd_pci_msi_enable;
+	info->chip->irq_disable		= vmd_pci_msi_disable;
+	return true;
+}
+
+#define VMD_MSI_FLAGS_SUPPORTED	(MSI_GENERIC_FLAGS_MASK | MSI_FLAG_PCI_MSIX)
+#define VMD_MSI_FLAGS_REQUIRED	(MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_NO_AFFINITY)
+
+static const struct msi_parent_ops vmd_msi_parent_ops = {
+	.supported_flags	= VMD_MSI_FLAGS_SUPPORTED,
+	.required_flags		= VMD_MSI_FLAGS_REQUIRED,
+	.bus_select_token	= DOMAIN_BUS_VMD_MSI,
+	.bus_select_mask	= MATCH_PCI_MSI,
+	.prefix			= "VMD-",
+	.init_dev_msi_info	= vmd_init_dev_msi_info,
+};
+
+static int vmd_create_irq_domain(struct vmd_dev *vmd)
+{
+	struct irq_domain_info info = {
+		.size		= vmd->msix_count,
+		.ops		= &vmd_msi_domain_ops,
+		.host_data	= vmd,
+	};
+
+	info.fwnode = irq_domain_alloc_named_id_fwnode("VMD-MSI",
+						       vmd->sysdata.domain);
+	if (!info.fwnode)
+		return -ENODEV;
+
+	vmd->irq_domain = msi_create_parent_irq_domain(&info,
+						       &vmd_msi_parent_ops);
+	if (!vmd->irq_domain) {
+		irq_domain_free_fwnode(info.fwnode);
+		return -ENODEV;
+	}
+
 	return 0;
 }
-
-static void vmd_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
-{
-	arg->desc = desc;
-}
-
-static struct msi_domain_ops vmd_msi_domain_ops = {
-	.get_hwirq	= vmd_get_hwirq,
-	.msi_init	= vmd_msi_init,
-	.msi_free	= vmd_msi_free,
-	.msi_prepare	= vmd_msi_prepare,
-	.set_desc	= vmd_set_desc,
-};
-
-static struct msi_domain_info vmd_msi_domain_info = {
-	.flags		= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-			  MSI_FLAG_NO_AFFINITY | MSI_FLAG_PCI_MSIX,
-	.ops		= &vmd_msi_domain_ops,
-	.chip		= &vmd_msi_controller,
-};
 
 static void vmd_set_msi_remapping(struct vmd_dev *vmd, bool enable)
 {
···
 	reg = enable ? (reg & ~VMCONFIG_MSI_REMAP) :
 		       (reg | VMCONFIG_MSI_REMAP);
 	pci_write_config_word(vmd->dev, PCI_REG_VMCONFIG, reg);
-}
-
-static int vmd_create_irq_domain(struct vmd_dev *vmd)
-{
-	struct fwnode_handle *fn;
-
-	fn = irq_domain_alloc_named_id_fwnode("VMD-MSI", vmd->sysdata.domain);
-	if (!fn)
-		return -ENODEV;
-
-	vmd->irq_domain = pci_msi_create_irq_domain(fn, &vmd_msi_domain_info, NULL);
-	if (!vmd->irq_domain) {
-		irq_domain_free_fwnode(fn);
-		return -ENODEV;
-	}
-
-	return 0;
 }
 
 static void vmd_remove_irq_domain(struct vmd_dev *vmd)
···
 {
 	struct vmd_dev *vmd = vmd_from_bus(bus);
 	void __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
-	unsigned long flags;
-	int ret = 0;
 
 	if (!addr)
 		return -EFAULT;
 
-	raw_spin_lock_irqsave(&vmd->cfg_lock, flags);
+	guard(raw_spinlock_irqsave)(&vmd->cfg_lock);
 	switch (len) {
 	case 1:
 		*value = readb(addr);
-		break;
+		return 0;
 	case 2:
 		*value = readw(addr);
-		break;
+		return 0;
 	case 4:
 		*value = readl(addr);
-		break;
+		return 0;
 	default:
-		ret = -EINVAL;
-		break;
+		return -EINVAL;
 	}
-	raw_spin_unlock_irqrestore(&vmd->cfg_lock, flags);
-	return ret;
 }
 
 /*
···
 {
 	struct vmd_dev *vmd = vmd_from_bus(bus);
 	void __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
-	unsigned long flags;
-	int ret = 0;
 
 	if (!addr)
 		return -EFAULT;
 
-	raw_spin_lock_irqsave(&vmd->cfg_lock, flags);
+	guard(raw_spinlock_irqsave)(&vmd->cfg_lock);
 	switch (len) {
 	case 1:
 		writeb(value, addr);
 		readb(addr);
-		break;
+		return 0;
 	case 2:
 		writew(value, addr);
 		readw(addr);
-		break;
+		return 0;
 	case 4:
 		writel(value, addr);
 		readl(addr);
-		break;
+		return 0;
 	default:
-		ret = -EINVAL;
-		break;
+		return -EINVAL;
 	}
-	raw_spin_unlock_irqrestore(&vmd->cfg_lock, flags);
-	return ret;
 }
 
 static struct pci_ops vmd_ops = {
···
 		ret = vmd_create_irq_domain(vmd);
 		if (ret)
 			return ret;
-
-		/*
-		 * Override the IRQ domain bus token so the domain can be
-		 * distinguished from a regular PCI/MSI domain.
-		 */
-		irq_domain_update_bus_token(vmd->irq_domain, DOMAIN_BUS_VMD_MSI);
 	} else {
 		vmd_set_msi_remapping(vmd, false);
 	}