powerpc/PCI: Override pcibios_window_alignment()
This patch implements pcibios_window_alignment() so powerpc platforms can
force P2P bridge windows to be at larger alignments than the PCI spec
requires.
[bhelgaas: changelog]
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index 2aa04f2..43fea54 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -99,6 +99,26 @@
kfree(phb);
}
+/*
+ * The function is used to return the minimal alignment
+ * for memory or I/O windows of the associated P2P bridge.
+ * By default, 4KiB alignment for I/O windows and 1MiB for
+ * memory windows.
+ */
+resource_size_t pcibios_window_alignment(struct pci_bus *bus,
+ unsigned long type)
+{
+ if (ppc_md.pcibios_window_alignment)
+ return ppc_md.pcibios_window_alignment(bus, type);
+
+ /*
+ * PCI core will figure out the default
+ * alignment: 4KiB for I/O and 1MiB for
+ * memory window.
+ */
+ return 1;
+}
+
static resource_size_t pcibios_io_size(const struct pci_controller *hose)
{
#ifdef CONFIG_PPC64