1 files changed, 83 insertions, 0 deletions

diff --git a/arch/x86/pci/k8-bus_64.c b/arch/x86/pci/k8-bus_64.c
new file mode 100644
index 000000000000..9cc813e29706
--- /dev/null
+++ b/arch/x86/pci/k8-bus_64.c
@@ -0,0 +1,83 @@
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <asm/mpspec.h>
+#include <linux/cpumask.h>
+
+/*
+ * This discovers the pcibus <-> node mapping on AMD K8.
+ *
+ * RED-PEN need to call this again on PCI hotplug
+ * RED-PEN empty cpus get reported wrong
+ */
+
+#define NODE_ID_REGISTER 0x60
+#define NODE_ID(dword) (dword & 0x07)
+#define LDT_BUS_NUMBER_REGISTER_0 0x94
+#define LDT_BUS_NUMBER_REGISTER_1 0xB4
+#define LDT_BUS_NUMBER_REGISTER_2 0xD4
+#define NR_LDT_BUS_NUMBER_REGISTERS 3
+#define SECONDARY_LDT_BUS_NUMBER(dword) ((dword >> 8) & 0xFF)
+#define SUBORDINATE_LDT_BUS_NUMBER(dword) ((dword >> 16) & 0xFF)
+#define PCI_DEVICE_ID_K8HTCONFIG 0x1100
+
+/**
+ * fill_mp_bus_to_cpumask()
+ * fills the mp_bus_to_cpumask array based according to the LDT Bus Number
+ * Registers found in the K8 northbridge
+ */
+__init static int
+fill_mp_bus_to_cpumask(void)
+{
+        struct pci_dev *nb_dev = NULL;
+        int i, j;
+        u32 ldtbus, nid;
+        static int lbnr[3] = {
+                LDT_BUS_NUMBER_REGISTER_0,
+                LDT_BUS_NUMBER_REGISTER_1,
+                LDT_BUS_NUMBER_REGISTER_2
+        };
+
+        while ((nb_dev = pci_get_device(PCI_VENDOR_ID_AMD,
+                        PCI_DEVICE_ID_K8HTCONFIG, nb_dev))) {
+                pci_read_config_dword(nb_dev, NODE_ID_REGISTER, &nid);
+
+                for (i = 0; i < NR_LDT_BUS_NUMBER_REGISTERS; i++) {
+                        pci_read_config_dword(nb_dev, lbnr[i], &ldtbus);
+                        /*
+                         * if there are no busses hanging off of the current
+                         * ldt link then both the secondary and subordinate
+                         * bus number fields are set to 0.
+                         * 
+                         * RED-PEN
+                         * This is slightly broken because it assumes
+                         * HT node IDs == Linux node ids, which is not always
+                         * true. However it is probably mostly true.
+                         */
+                        if (!(SECONDARY_LDT_BUS_NUMBER(ldtbus) == 0
+                                && SUBORDINATE_LDT_BUS_NUMBER(ldtbus) == 0)) {
+                                for (j = SECONDARY_LDT_BUS_NUMBER(ldtbus);
+                                     j <= SUBORDINATE_LDT_BUS_NUMBER(ldtbus);
+                                     j++) { 
+                                        struct pci_bus *bus;
+                                        struct pci_sysdata *sd;
+
+                                        long node = NODE_ID(nid);
+                                        /* Algorithm a bit dumb, but
+                                           it shouldn't matter here */
+                                        bus = pci_find_bus(0, j);
+                                        if (!bus)
+                                                continue;
+                                        if (!node_online(node))
+                                                node = 0;
+
+                                        sd = bus->sysdata;
+                                        sd->node = node;
+                                }               
+                        }
+                }
+        }
+
+        return 0;
+}
+
+fs_initcall(fill_mp_bus_to_cpumask);