3 files changed, 59 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/pci.c b/arch/powerpc/platforms/pseries/pci.c
index 0b580f413a9a..5f93856cdf47 100644
--- a/arch/powerpc/platforms/pseries/pci.c
+++ b/arch/powerpc/platforms/pseries/pci.c
@@ -108,3 +108,56 @@ static void fixup_winbond_82c105(struct pci_dev* dev)
 }
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_WINBOND, PCI_DEVICE_ID_WINBOND_82C105,
 			 fixup_winbond_82c105);
+
+int pseries_root_bridge_prepare(struct pci_host_bridge *bridge)
+{
+	struct device_node *dn, *pdn;
+	struct pci_bus *bus;
+	const uint32_t *pcie_link_speed_stats;
+
+	bus = bridge->bus;
+
+	dn = pcibios_get_phb_of_node(bus);
+	if (!dn)
+		return 0;
+
+	for (pdn = dn; pdn != NULL; pdn = of_get_next_parent(pdn)) {
+		pcie_link_speed_stats = (const uint32_t *) of_get_property(pdn,
+			"ibm,pcie-link-speed-stats", NULL);
+		if (pcie_link_speed_stats)
+			break;
+	}
+
+	of_node_put(pdn);
+
+	if (!pcie_link_speed_stats) {
+		pr_err("no ibm,pcie-link-speed-stats property\n");
+		return 0;
+	}
+
+	switch (pcie_link_speed_stats[0]) {
+	case 0x01:
+		bus->max_bus_speed = PCIE_SPEED_2_5GT;
+		break;
+	case 0x02:
+		bus->max_bus_speed = PCIE_SPEED_5_0GT;
+		break;
+	default:
+		bus->max_bus_speed = PCI_SPEED_UNKNOWN;
+		break;
+	}
+
+	switch (pcie_link_speed_stats[1]) {
+	case 0x01:
+		bus->cur_bus_speed = PCIE_SPEED_2_5GT;
+		break;
+	case 0x02:
+		bus->cur_bus_speed = PCIE_SPEED_5_0GT;
+		break;
+	default:
+		bus->cur_bus_speed = PCI_SPEED_UNKNOWN;
+		break;
+	}
+
+	return 0;
+}
diff --git a/arch/powerpc/platforms/pseries/pseries.h b/arch/powerpc/platforms/pseries/pseries.h
index 8af71e4cc17f..c2a3a258001c 100644
--- a/arch/powerpc/platforms/pseries/pseries.h
+++ b/arch/powerpc/platforms/pseries/pseries.h
@@ -63,4 +63,8 @@ extern int dlpar_detach_node(struct device_node *);
 /* Snooze Delay, pseries_idle */
 DECLARE_PER_CPU(long, smt_snooze_delay);
 
+/* PCI root bridge prepare function override for pseries */
+struct pci_host_bridge;
+int pseries_root_bridge_prepare(struct pci_host_bridge *bridge);
+
 #endif /* _PSERIES_PSERIES_H */
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index ac932a9eb440..c11c8238797c 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -466,6 +466,8 @@ static void __init pSeries_setup_arch(void)
 	else
 		ppc_md.enable_pmcs = power4_enable_pmcs;
 
+	ppc_md.pcibios_root_bridge_prepare = pseries_root_bridge_prepare;
+
 	if (firmware_has_feature(FW_FEATURE_SET_MODE)) {
 		long rc;
 		if ((rc = pSeries_enable_reloc_on_exc()) != H_SUCCESS) {