diff mbox series

[2/6] PCI: restore resource alignment

Message ID 20240709133610.1089420-3-stewart.hildebrand@amd.com (mailing list archive)
State Superseded
Delegated to: Bjorn Helgaas
Headers show
Series PCI: align small (<4k) BARs | expand

Commit Message

Stewart Hildebrand July 9, 2024, 1:35 p.m. UTC 
Devices with alignment specified will lose their alignment in cases when
the bridge resources have been released, e.g. due to insufficient bridge
window size. Restore the alignment.

Signed-off-by: Stewart Hildebrand <stewart.hildebrand@amd.com>
---
 drivers/pci/setup-bus.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
diff mbox series

Patch

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 23082bc0ca37..ab7510ce6917 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1594,6 +1594,23 @@  static void __pci_bridge_assign_resources(const struct pci_dev *bridge,
 	}
 }
 
+static void restore_child_resource_alignment(struct pci_bus *bus)
+{
+	struct pci_dev *dev;
+
+	list_for_each_entry(dev, &bus->devices, bus_list) {
+		struct pci_bus *b;
+
+		pci_reassigndev_resource_alignment(dev);
+
+		b = dev->subordinate;
+		if (!b)
+			continue;
+
+		restore_child_resource_alignment(b);
+	}
+}
+
 #define PCI_RES_TYPE_MASK \
 	(IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH |\
 	 IORESOURCE_MEM_64)
@@ -1648,6 +1665,8 @@  static void pci_bridge_release_resources(struct pci_bus *bus,
 		r->start = 0;
 		r->flags = 0;
 
+		restore_child_resource_alignment(bus);
+
 		/* Avoiding touch the one without PREF */
 		if (type & IORESOURCE_PREFETCH)
 			type = IORESOURCE_PREFETCH;