quoted

And I'm not sure why the new callback is necessary ->

I was demoing your suggestion but...

quoted

quoted

        if (acpi_dma_supported(adev))
                pdevinfo.dma_mask = DMA_BIT_MASK(32);

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index bc68d93..6b72fcb 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c

@@ -527,6 +527,49 @@ struct irq_domain *iort_get_device_domain(struct device *dev, u32 req_id)
        return irq_find_matching_fwnode(handle, DOMAIN_BUS_PCI_MSI);
 }

+/**
+ * iort_get_platform_device_domain() - Find MSI domain related to a
+ * platform device
+ * @dev: the dev pointer associated with the platform device
+ *
+ * Returns: the MSI domain for this device, NULL otherwise
+ */
+static struct irq_domain *iort_get_platform_device_domain(struct device *dev)
+{
+       struct acpi_iort_node *node, *msi_parent;
+       struct fwnode_handle *iort_fwnode;
+       struct acpi_iort_its_group *its;
+
+       /* find its associated iort node */
+       node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
+                             iort_match_node_callback, dev);
+       if (!node)
+               return NULL;
+
+       /* then find its msi parent node */
+       msi_parent = iort_node_get_id(node, NULL, IORT_MSI_TYPE, 0);
+       if (!msi_parent)
+               return NULL;
+
+       /* Move to ITS specific data */
+       its = (struct acpi_iort_its_group *)msi_parent->node_data;
+
+       iort_fwnode = iort_find_domain_token(its->identifiers[0]);
+       if (!iort_fwnode)
+               return NULL;
+
+       return irq_find_matching_fwnode(iort_fwnode, DOMAIN_BUS_PLATFORM_MSI);
+}
+
+void acpi_configure_pmsi_domain(struct device *dev)
+{
+       struct irq_domain *msi_domain;
+
+       msi_domain = iort_get_platform_device_domain(dev);
+       if (msi_domain)
+               dev_set_msi_domain(dev, msi_domain);
+}
+
 static int __get_pci_rid(struct pci_dev *pdev, u16 alias, void *data)
 {
        u32 *rid = data;

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index c4af003..3e68f31 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c

@@ -537,6 +537,9 @@ struct platform_device *platform_device_register_full(
                        goto err;
        }

+       if (pdevinfo->pre_add_cb)
+               pdevinfo->pre_add_cb(&pdev->dev);
+

-> because it looks like this might be done in acpi_platform_notify()
for platform devices.

It works and I just simply add the code below:

diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c
index f8d6564..e0cd649 100644
--- a/drivers/acpi/glue.c
+++ b/drivers/acpi/glue.c

@@ -13,6 +13,7 @@
 #include <linux/slab.h>
 #include <linux/rwsem.h>
 #include <linux/acpi.h>
+#include <linux/acpi_iort.h>
 #include <linux/dma-mapping.h>

 #include "internal.h"

@@ -315,6 +316,8 @@ static int acpi_platform_notify(struct device *dev)
        if (!adev)
                goto out;

+ acpi_configure_pmsi_domain(dev);
+