--- zzzz-none-000/linux-3.10.107/drivers/xen/pci.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/drivers/xen/pci.c	2021-02-04 17:41:59.000000000 +0000
@@ -19,6 +19,7 @@
 
 #include <linux/pci.h>
 #include <linux/acpi.h>
+#include <linux/pci-acpi.h>
 #include <xen/xen.h>
 #include <xen/interface/physdev.h>
 #include <xen/interface/xen.h>
@@ -26,6 +27,9 @@
 #include <asm/xen/hypervisor.h>
 #include <asm/xen/hypercall.h>
 #include "../pci/pci.h"
+#ifdef CONFIG_PCI_MMCONFIG
+#include <asm/pci_x86.h>
+#endif
 
 static bool __read_mostly pci_seg_supported = true;
 
@@ -38,33 +42,48 @@
 #endif
 
 	if (pci_seg_supported) {
-		struct physdev_pci_device_add add = {
-			.seg = pci_domain_nr(pci_dev->bus),
-			.bus = pci_dev->bus->number,
-			.devfn = pci_dev->devfn
+		struct {
+			struct physdev_pci_device_add add;
+			uint32_t pxm;
+		} add_ext = {
+			.add.seg = pci_domain_nr(pci_dev->bus),
+			.add.bus = pci_dev->bus->number,
+			.add.devfn = pci_dev->devfn
 		};
+		struct physdev_pci_device_add *add = &add_ext.add;
+
 #ifdef CONFIG_ACPI
 		acpi_handle handle;
 #endif
 
 #ifdef CONFIG_PCI_IOV
 		if (pci_dev->is_virtfn) {
-			add.flags = XEN_PCI_DEV_VIRTFN;
-			add.physfn.bus = physfn->bus->number;
-			add.physfn.devfn = physfn->devfn;
+			add->flags = XEN_PCI_DEV_VIRTFN;
+			add->physfn.bus = physfn->bus->number;
+			add->physfn.devfn = physfn->devfn;
 		} else
 #endif
 		if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn))
-			add.flags = XEN_PCI_DEV_EXTFN;
+			add->flags = XEN_PCI_DEV_EXTFN;
 
 #ifdef CONFIG_ACPI
-		handle = DEVICE_ACPI_HANDLE(&pci_dev->dev);
-		if (!handle && pci_dev->bus->bridge)
-			handle = DEVICE_ACPI_HANDLE(pci_dev->bus->bridge);
+		handle = ACPI_HANDLE(&pci_dev->dev);
 #ifdef CONFIG_PCI_IOV
 		if (!handle && pci_dev->is_virtfn)
-			handle = DEVICE_ACPI_HANDLE(physfn->bus->bridge);
+			handle = ACPI_HANDLE(physfn->bus->bridge);
 #endif
+		if (!handle) {
+			/*
+			 * This device was not listed in the ACPI name space at
+			 * all. Try to get acpi handle of parent pci bus.
+			 */
+			struct pci_bus *pbus;
+			for (pbus = pci_dev->bus; pbus; pbus = pbus->parent) {
+				handle = acpi_pci_get_bridge_handle(pbus);
+				if (handle)
+					break;
+			}
+		}
 		if (handle) {
 			acpi_status status;
 
@@ -74,8 +93,8 @@
 				status = acpi_evaluate_integer(handle, "_PXM",
 							       NULL, &pxm);
 				if (ACPI_SUCCESS(status)) {
-					add.optarr[0] = pxm;
-					add.flags |= XEN_PCI_DEV_PXM;
+					add->optarr[0] = pxm;
+					add->flags |= XEN_PCI_DEV_PXM;
 					break;
 				}
 				status = acpi_get_parent(handle, &handle);
@@ -83,7 +102,7 @@
 		}
 #endif /* CONFIG_ACPI */
 
-		r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_add, &add);
+		r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_add, add);
 		if (r != -ENOSYS)
 			return r;
 		pci_seg_supported = false;
@@ -192,3 +211,49 @@
 }
 
 arch_initcall(register_xen_pci_notifier);
+
+#ifdef CONFIG_PCI_MMCONFIG
+static int __init xen_mcfg_late(void)
+{
+	struct pci_mmcfg_region *cfg;
+	int rc;
+
+	if (!xen_initial_domain())
+		return 0;
+
+	if ((pci_probe & PCI_PROBE_MMCONF) == 0)
+		return 0;
+
+	if (list_empty(&pci_mmcfg_list))
+		return 0;
+
+	/* Check whether they are in the right area. */
+	list_for_each_entry(cfg, &pci_mmcfg_list, list) {
+		struct physdev_pci_mmcfg_reserved r;
+
+		r.address = cfg->address;
+		r.segment = cfg->segment;
+		r.start_bus = cfg->start_bus;
+		r.end_bus = cfg->end_bus;
+		r.flags = XEN_PCI_MMCFG_RESERVED;
+
+		rc = HYPERVISOR_physdev_op(PHYSDEVOP_pci_mmcfg_reserved, &r);
+		switch (rc) {
+		case 0:
+		case -ENOSYS:
+			continue;
+
+		default:
+			pr_warn("Failed to report MMCONFIG reservation"
+				" state for %s to hypervisor"
+				" (%d)\n",
+				cfg->name, rc);
+		}
+	}
+	return 0;
+}
+/*
+ * Needs to be done after acpi_init which are subsys_initcall.
+ */
+subsys_initcall_sync(xen_mcfg_late);
+#endif