kernel-fxtec-pro1x/arch/x86/pci/k8-bus_64.c
Yinghai Lu 871d5f8dd0 x86: get mp_bus_to_node early
Currently, on an amd k8 system with multi ht chains, the numa_node of
pci devices under /sys/devices/pci0000:80/* is always 0, even if that
chain is on node 1 or 2 or 3.

Workaround: pcibus_to_node(bus) is used when we want to get the node that
pci_device is on.

In struct device, we already have numa_node member, and we could use
dev_to_node()/set_dev_node() to get and set numa_node in the device.
set_dev_node is called in pci_device_add() with pcibus_to_node(bus),
and pcibus_to_node uses bus->sysdata for nodeid.

The problem is when pci_add_device is called, bus->sysdata is not assigned
correct nodeid yet. The result is that numa_node will always be 0.

pcibios_scan_root and pci_scan_root could take sysdata. So we need to get
mp_bus_to_node mapping before these two are called, and thus
get_mp_bus_to_node could get correct node for sysdata in root bus.

In scanning of the root bus, all child busses will take parent bus sysdata.
So all pci_device->dev.numa_node will be assigned correctly and automatically.

Later we could use dev_to_node(&pci_dev->dev) to get numa_node, and we
could also could make other bus specific device get the correct numa_node
too.

This is an updated version of pci_sysdata and Jeff's pci_domain patch.

[ mingo@elte.hu: build fix ]

Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-26 23:41:04 +02:00

123 lines
2.9 KiB
C

#include <linux/init.h>
#include <linux/pci.h>
#include <asm/pci-direct.h>
#include <asm/mpspec.h>
#include <linux/cpumask.h>
#include <linux/topology.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
#ifdef CONFIG_NUMA
#define BUS_NR 256
static int mp_bus_to_node[BUS_NR];
void set_mp_bus_to_node(int busnum, int node)
{
if (busnum >= 0 && busnum < BUS_NR)
mp_bus_to_node[busnum] = node;
}
int get_mp_bus_to_node(int busnum)
{
int node = -1;
if (busnum < 0 || busnum > (BUS_NR - 1))
return node;
node = mp_bus_to_node[busnum];
/*
* let numa_node_id to decide it later in dma_alloc_pages
* if there is no ram on that node
*/
if (node != -1 && !node_online(node))
node = -1;
return node;
}
#endif
/**
* early_fill_mp_bus_to_node()
* called before pcibios_scan_root and pci_scan_bus
* fills the mp_bus_to_cpumask array based according to the LDT Bus Number
* Registers found in the K8 northbridge
*/
__init static int
early_fill_mp_bus_to_node(void)
{
#ifdef CONFIG_NUMA
int i, j;
unsigned slot;
u32 ldtbus, nid;
u32 id;
static int lbnr[3] = {
LDT_BUS_NUMBER_REGISTER_0,
LDT_BUS_NUMBER_REGISTER_1,
LDT_BUS_NUMBER_REGISTER_2
};
for (i = 0; i < BUS_NR; i++)
mp_bus_to_node[i] = -1;
if (!early_pci_allowed())
return -1;
for (slot = 0x18; slot < 0x20; slot++) {
id = read_pci_config(0, slot, 0, PCI_VENDOR_ID);
if (id != (PCI_VENDOR_ID_AMD | (PCI_DEVICE_ID_K8HTCONFIG<<16)))
break;
nid = read_pci_config(0, slot, 0, NODE_ID_REGISTER);
for (i = 0; i < NR_LDT_BUS_NUMBER_REGISTERS; i++) {
ldtbus = read_pci_config(0, slot, 0, lbnr[i]);
/*
* 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++) {
int node = NODE_ID(nid);
mp_bus_to_node[j] = (unsigned char)node;
}
}
}
}
for (i = 0; i < BUS_NR; i++) {
int node = mp_bus_to_node[i];
if (node >= 0)
printk(KERN_DEBUG "bus: %02x to node: %02x\n", i, node);
}
#endif
return 0;
}
postcore_initcall(early_fill_mp_bus_to_node);