[PATCH v2] driver core: platform: Setup device MSI domain just before driver probe

[Anup Patel]

On RISC-V, the MSI controller (aka RISC-V IMSIC) is probed as a regular
platform device and MSI client drivers are always probed after the MSI
controller driver using fw_devlink. Unfortunately, this is not sufficient
to ensure device MSI domain is set for MSI client devices before driver
probe because OF framework sets device MSI domain at the time of platform
device creation whereas ACPI framework expects arch specific code to set
the device MSI domain at the time of platform device creation.

Currently, to address the problem of device MSI domain being not set
correctly, various RISC-V MSI client drivers explicitly set device
MSI domain in the driver probe function using below code pattern:

	/*
	 * The device MSI domain for platform devices on RISC-V architecture
	 * is only available after the MSI controller driver is probed so,
	 * explicitly configure here.
	 */
	if (!dev_get_msi_domain(dev)) {
		/*
		 * The device MSI domain for OF devices is only set at the
		 * time of populating/creating OF device. If the device MSI
		 * domain is discovered later after the OF device is created
		 * then we need to set it explicitly before using any platform
		 * MSI functions.
		 */
		if (is_of_node(fwnode)) {
			of_msi_configure(dev, dev_of_node(dev));
		} else if (is_acpi_device_node(fwnode)) {
			struct irq_domain *msi_domain;
			msi_domain = irq_find_matching_fwnode(imsic_acpi_get_fwnode(dev),
							      DOMAIN_BUS_PLATFORM_MSI);
			dev_set_msi_domain(dev, msi_domain);
		}

		if (!dev_get_msi_domain(dev))
			return -EPROBE_DEFER;
	}

Instead of the above approach, extend the platform_dma_configure() to set
device MSI domain for both OF and ACPI based platform devices before driver
probe and remove the duplicate code pattern from RISC-V MSI client drivers.

Co-developed-by: Sunil V L <sunilvl@xxxxxxxxxxxxxxxx>
Signed-off-by: Sunil V L <sunilvl@xxxxxxxxxxxxxxxx>
Signed-off-by: Anup Patel <anup.patel@xxxxxxxxxxxxxxxx>
---
Changes since v1:
 - Rebased on Linux-7.2-rc5
 - Minor improvement to commit description
---
 drivers/acpi/riscv/irq.c                | 13 +++++++++++
 drivers/acpi/scan.c                     | 10 +++++++++
 drivers/base/platform.c                 |  4 ++++
 drivers/iommu/riscv/iommu-platform.c    |  9 --------
 drivers/irqchip/irq-riscv-aplic-msi.c   | 27 -----------------------
 drivers/irqchip/irq-riscv-rpmi-sysmsi.c | 29 -------------------------
 drivers/mailbox/riscv-sbi-mpxy-mbox.c   | 29 -------------------------
 include/acpi/acpi_bus.h                 |  1 +
 include/linux/acpi.h                    | 10 +++++++++
 9 files changed, 38 insertions(+), 94 deletions(-)

diff --git a/drivers/acpi/riscv/irq.c b/drivers/acpi/riscv/irq.c
index 9b88d0993e88..17fa5dcdd2c0 100644
--- a/drivers/acpi/riscv/irq.c
+++ b/drivers/acpi/riscv/irq.c
@@ -5,8 +5,11 @@
  */
 
 #include <linux/acpi.h>
+#include <linux/device.h>
 #include <linux/sort.h>
 #include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip/riscv-imsic.h>
 
 #include "init.h"
 
@@ -397,6 +400,16 @@ static u32 riscv_acpi_add_irq_dep(acpi_handle handle)
 	return count;
 }
 
+void acpi_arch_msi_configure(struct device *dev)
+{
+	struct irq_domain *msi_domain;
+
+	msi_domain = irq_find_matching_fwnode(imsic_acpi_get_fwnode(dev),
+					      DOMAIN_BUS_PLATFORM_MSI);
+	if (msi_domain)
+		dev_set_msi_domain(dev, msi_domain);
+}
+
 u32 arch_acpi_add_auto_dep(acpi_handle handle)
 {
 	if (acpi_has_method(handle, "_PRT"))
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 9a7ac2eb9ce0..75c52f6bbbe8 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1650,6 +1650,16 @@ static int acpi_iommu_configure_id(struct device *dev, const u32 *id_in)
 
 #endif /* !CONFIG_IOMMU_API */
 
+/**
+ * acpi_msi_configure - Set-up MSI domain for the device.
+ * @dev: The pointer to the device
+ */
+void acpi_msi_configure(struct device *dev)
+{
+	acpi_arch_msi_configure(dev);
+}
+EXPORT_SYMBOL_GPL(acpi_msi_configure);
+
 /**
  * acpi_dma_configure_id - Set-up DMA configuration for the device.
  * @dev: The pointer to the device
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index fb9120b0bcfe..965ed6ae5bb5 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -1477,8 +1477,12 @@ static int platform_dma_configure(struct device *dev)
 	int ret = 0;
 
 	if (is_of_node(fwnode)) {
+		if (!dev_get_msi_domain(dev))
+			of_msi_configure(dev, dev->of_node);
 		ret = of_dma_configure(dev, to_of_node(fwnode), true);
 	} else if (is_acpi_device_node(fwnode)) {
+		if (!dev_get_msi_domain(dev))
+			acpi_msi_configure(dev);
 		attr = acpi_get_dma_attr(to_acpi_device_node(fwnode));
 		ret = acpi_dma_configure(dev, attr);
 	}
diff --git a/drivers/iommu/riscv/iommu-platform.c b/drivers/iommu/riscv/iommu-platform.c
index 399ba8fe1b3e..ddc6370b96b0 100644
--- a/drivers/iommu/riscv/iommu-platform.c
+++ b/drivers/iommu/riscv/iommu-platform.c
@@ -48,7 +48,6 @@ static int riscv_iommu_platform_probe(struct platform_device *pdev)
 	enum riscv_iommu_igs_settings igs;
 	struct device *dev = &pdev->dev;
 	struct riscv_iommu_device *iommu = NULL;
-	struct irq_domain *msi_domain;
 	struct resource *res = NULL;
 	int vec, ret;
 
@@ -74,14 +73,6 @@ static int riscv_iommu_platform_probe(struct platform_device *pdev)
 	switch (igs) {
 	case RISCV_IOMMU_CAPABILITIES_IGS_BOTH:
 	case RISCV_IOMMU_CAPABILITIES_IGS_MSI:
-		if (is_of_node(dev_fwnode(dev))) {
-			of_msi_configure(dev, to_of_node(dev->fwnode));
-		} else {
-			msi_domain = irq_find_matching_fwnode(imsic_acpi_get_fwnode(dev),
-							      DOMAIN_BUS_PLATFORM_MSI);
-			dev_set_msi_domain(dev, msi_domain);
-		}
-
 		if (!dev_get_msi_domain(dev)) {
 			dev_warn(dev, "failed to find an MSI domain\n");
 			goto msi_fail;
diff --git a/drivers/irqchip/irq-riscv-aplic-msi.c b/drivers/irqchip/irq-riscv-aplic-msi.c
index fb8d1838609f..2cf5d42cd66a 100644
--- a/drivers/irqchip/irq-riscv-aplic-msi.c
+++ b/drivers/irqchip/irq-riscv-aplic-msi.c
@@ -175,7 +175,6 @@ static const struct msi_domain_template aplic_msi_template = {
 int aplic_msi_setup(struct device *dev, void __iomem *regs)
 {
 	const struct imsic_global_config *imsic_global;
-	struct irq_domain *msi_domain;
 	struct aplic_priv *priv;
 	struct aplic_msicfg *mc;
 	phys_addr_t pa;
@@ -245,32 +244,6 @@ int aplic_msi_setup(struct device *dev, void __iomem *regs)
 	/* Setup global config and interrupt delivery */
 	aplic_init_hw_global(priv, true);
 
-	/* Set the APLIC device MSI domain if not available */
-	if (!dev_get_msi_domain(dev)) {
-		/*
-		 * The device MSI domain for OF devices is only set at the
-		 * time of populating/creating OF device. If the device MSI
-		 * domain is discovered later after the OF device is created
-		 * then we need to set it explicitly before using any platform
-		 * MSI functions.
-		 *
-		 * In case of APLIC device, the parent MSI domain is always
-		 * IMSIC and the IMSIC MSI domains are created later through
-		 * the platform driver probing so we set it explicitly here.
-		 */
-		if (is_of_node(dev->fwnode)) {
-			of_msi_configure(dev, to_of_node(dev->fwnode));
-		} else {
-			msi_domain = irq_find_matching_fwnode(imsic_acpi_get_fwnode(dev),
-							      DOMAIN_BUS_PLATFORM_MSI);
-			if (msi_domain)
-				dev_set_msi_domain(dev, msi_domain);
-		}
-
-		if (!dev_get_msi_domain(dev))
-			return -EPROBE_DEFER;
-	}
-
 	if (!msi_create_device_irq_domain(dev, MSI_DEFAULT_DOMAIN, &aplic_msi_template,
 					  priv->nr_irqs + 1, priv, priv)) {
 		dev_err(dev, "failed to create MSI irq domain\n");
diff --git a/drivers/irqchip/irq-riscv-rpmi-sysmsi.c b/drivers/irqchip/irq-riscv-rpmi-sysmsi.c
index 612f3972f7af..e6cdb4b635a6 100644
--- a/drivers/irqchip/irq-riscv-rpmi-sysmsi.c
+++ b/drivers/irqchip/irq-riscv-rpmi-sysmsi.c
@@ -260,35 +260,6 @@ static int rpmi_sysmsi_probe(struct platform_device *pdev)
 			riscv_acpi_update_gsi_range(priv->gsi_base, priv->nr_irqs);
 	}
 
-	/*
-	 * The device MSI domain for platform devices on RISC-V architecture
-	 * is only available after the MSI controller driver is probed so,
-	 * explicitly configure here.
-	 */
-	if (!dev_get_msi_domain(dev)) {
-		/*
-		 * The device MSI domain for OF devices is only set at the
-		 * time of populating/creating OF device. If the device MSI
-		 * domain is discovered later after the OF device is created
-		 * then we need to set it explicitly before using any platform
-		 * MSI functions.
-		 */
-		if (is_of_node(fwnode)) {
-			of_msi_configure(dev, dev_of_node(dev));
-		} else if (is_acpi_device_node(fwnode)) {
-			struct irq_domain *msi_domain;
-
-			msi_domain = irq_find_matching_fwnode(imsic_acpi_get_fwnode(dev),
-							      DOMAIN_BUS_PLATFORM_MSI);
-			dev_set_msi_domain(dev, msi_domain);
-		}
-
-		if (!dev_get_msi_domain(dev)) {
-			mbox_free_channel(priv->chan);
-			return -EPROBE_DEFER;
-		}
-	}
-
 	if (!msi_create_device_irq_domain(dev, MSI_DEFAULT_DOMAIN,
 					  &rpmi_sysmsi_template,
 					  priv->nr_irqs, priv, priv)) {
diff --git a/drivers/mailbox/riscv-sbi-mpxy-mbox.c b/drivers/mailbox/riscv-sbi-mpxy-mbox.c
index 7c9c006b7244..759512aba19f 100644
--- a/drivers/mailbox/riscv-sbi-mpxy-mbox.c
+++ b/drivers/mailbox/riscv-sbi-mpxy-mbox.c
@@ -902,35 +902,6 @@ static int mpxy_mbox_probe(struct platform_device *pdev)
 
 	/* Setup MSIs for mailbox (if required) */
 	if (mbox->msi_count) {
-		/*
-		 * The device MSI domain for platform devices on RISC-V architecture
-		 * is only available after the MSI controller driver is probed so,
-		 * explicitly configure here.
-		 */
-		if (!dev_get_msi_domain(dev)) {
-			struct fwnode_handle *fwnode = dev_fwnode(dev);
-
-			/*
-			 * The device MSI domain for OF devices is only set at the
-			 * time of populating/creating OF device. If the device MSI
-			 * domain is discovered later after the OF device is created
-			 * then we need to set it explicitly before using any platform
-			 * MSI functions.
-			 */
-			if (is_of_node(fwnode)) {
-				of_msi_configure(dev, dev_of_node(dev));
-			} else if (is_acpi_device_node(fwnode)) {
-				struct irq_domain *msi_domain;
-
-				msi_domain = irq_find_matching_fwnode(imsic_acpi_get_fwnode(dev),
-								      DOMAIN_BUS_PLATFORM_MSI);
-				dev_set_msi_domain(dev, msi_domain);
-			}
-
-			if (!dev_get_msi_domain(dev))
-				return -EPROBE_DEFER;
-		}
-
 		mbox->msi_index_to_channel = devm_kcalloc(dev, mbox->msi_count,
 							  sizeof(*mbox->msi_index_to_channel),
 							  GFP_KERNEL);
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 714d111d8053..d971d6bc14d7 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -750,6 +750,7 @@ bool acpi_dma_supported(const struct acpi_device *adev);
 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev);
 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
 			   struct fwnode_handle *fwnode);
+void acpi_msi_configure(struct device *dev);
 int acpi_dma_get_range(struct device *dev, const struct bus_dma_region **map);
 int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
 			   const u32 *input_id);
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 60ab50cb8930..5e2e377c48b4 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -260,6 +260,12 @@ acpi_numa_processor_affinity_init(struct acpi_srat_cpu_affinity *pa) { }
 
 void acpi_numa_x2apic_affinity_init(struct acpi_srat_x2apic_cpu_affinity *pa);
 
+#if defined(CONFIG_RISCV)
+void acpi_arch_msi_configure(struct device *dev);
+#else
+static inline void acpi_arch_msi_configure(struct device *dev) { }
+#endif
+
 #if defined(CONFIG_ARM64) || defined(CONFIG_LOONGARCH)
 void acpi_arch_dma_setup(struct device *dev);
 #else
@@ -1060,6 +1066,10 @@ static inline int acpi_dma_get_range(struct device *dev, const struct bus_dma_re
 	return -ENODEV;
 }
 
+static inline void acpi_msi_configure(struct device *dev)
+{
+}
+
 static inline int acpi_dma_configure(struct device *dev,
 				     enum dev_dma_attr attr)
 {
-- 
2.43.0