PCI: Add support for detection of PCIe and PCI-X bus speeds
Both PCIe and PCI-X bridges report their secondary bus speed in their
respective capabilities.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 51cf898..188ee9c 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -393,6 +393,25 @@
return b;
}
+static unsigned char pcix_bus_speed[] = {
+ PCI_SPEED_UNKNOWN, /* 0 */
+ PCI_SPEED_66MHz_PCIX, /* 1 */
+ PCI_SPEED_100MHz_PCIX, /* 2 */
+ PCI_SPEED_133MHz_PCIX, /* 3 */
+ PCI_SPEED_UNKNOWN, /* 4 */
+ PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
+ PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
+ PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
+ PCI_SPEED_UNKNOWN, /* 8 */
+ PCI_SPEED_66MHz_PCIX_266, /* 9 */
+ PCI_SPEED_100MHz_PCIX_266, /* A */
+ PCI_SPEED_133MHz_PCIX_266, /* B */
+ PCI_SPEED_UNKNOWN, /* C */
+ PCI_SPEED_66MHz_PCIX_533, /* D */
+ PCI_SPEED_100MHz_PCIX_533, /* E */
+ PCI_SPEED_133MHz_PCIX_533 /* F */
+};
+
static unsigned char pcie_link_speed[] = {
PCI_SPEED_UNKNOWN, /* 0 */
PCIE_SPEED_2_5GT, /* 1 */
@@ -418,6 +437,51 @@
}
EXPORT_SYMBOL_GPL(pcie_update_link_speed);
+static void pci_set_bus_speed(struct pci_bus *bus)
+{
+ struct pci_dev *bridge = bus->self;
+ int pos;
+
+ pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
+ if (pos) {
+ u16 status;
+ enum pci_bus_speed max;
+ pci_read_config_word(bridge, pos + 2, &status);
+
+ if (status & 0x8000) {
+ max = PCI_SPEED_133MHz_PCIX_533;
+ } else if (status & 0x4000) {
+ max = PCI_SPEED_133MHz_PCIX_266;
+ } else if (status & 0x0002) {
+ if (((status >> 12) & 0x3) == 2) {
+ max = PCI_SPEED_133MHz_PCIX_ECC;
+ } else {
+ max = PCI_SPEED_133MHz_PCIX;
+ }
+ } else {
+ max = PCI_SPEED_66MHz_PCIX;
+ }
+
+ bus->max_bus_speed = max;
+ bus->cur_bus_speed = pcix_bus_speed[(status >> 6) & 0xf];
+
+ return;
+ }
+
+ pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
+ if (pos) {
+ u32 linkcap;
+ u16 linksta;
+
+ pci_read_config_dword(bridge, pos + PCI_EXP_LNKCAP, &linkcap);
+ bus->max_bus_speed = pcie_link_speed[linkcap & 0xf];
+
+ pci_read_config_word(bridge, pos + PCI_EXP_LNKSTA, &linksta);
+ pcie_update_link_speed(bus, linksta);
+ }
+}
+
+
static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
struct pci_dev *bridge, int busnr)
{
@@ -457,6 +521,8 @@
child->self = bridge;
child->bridge = get_device(&bridge->dev);
+ pci_set_bus_speed(child);
+
/* Set up default resource pointers and names.. */
for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];