arch/x86/pci/amd_bus.c - kernel/skids - Git at Google

 #include <linux/init.h>
 #include <linux/pci.h>
 #include <linux/topology.h>
 #include <linux/cpu.h>
 #include <linux/range.h>

 #include <asm/pci_x86.h>

 #include <asm/pci-direct.h>

 #include "bus_numa.h"

 /*
  * This discovers the pcibus <-> node mapping on AMD K8.
  * also get peer root bus resource for io,mmio
  */

 struct pci_hostbridge_probe {
 	u32 bus;
 	u32 slot;
 	u32 vendor;
 	u32 device;
 };

 static struct pci_hostbridge_probe pci_probes[] __initdata = {
 	{ 0, 0x18, PCI_VENDOR_ID_AMD, 0x1100 },
 	{ 0, 0x18, PCI_VENDOR_ID_AMD, 0x1200 },
 	{ 0xff, 0, PCI_VENDOR_ID_AMD, 0x1200 },
 	{ 0, 0x18, PCI_VENDOR_ID_AMD, 0x1300 },
 };

 static u64 __initdata fam10h_mmconf_start;
 static u64 __initdata fam10h_mmconf_end;
 static void __init get_pci_mmcfg_amd_fam10h_range(void)
 {
 	u32 address;
 	u64 base, msr;
 	unsigned segn_busn_bits;

 	/* assume all cpus from fam10h have mmconf */
         if (boot_cpu_data.x86 < 0x10)
 		return;

 	address = MSR_FAM10H_MMIO_CONF_BASE;
 	rdmsrl(address, msr);

 	/* mmconfig is not enable */
 	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
 		return;

 	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);

 	segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
 			 FAM10H_MMIO_CONF_BUSRANGE_MASK;

 	fam10h_mmconf_start = base;
 	fam10h_mmconf_end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
 }

 #define RANGE_NUM 16

 /**
  * 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
  */
 static int __init early_fill_mp_bus_info(void)
 {
 	int i;
 	int j;
 	unsigned bus;
 	unsigned slot;
 	int node;
 	int link;
 	int def_node;
 	int def_link;
 	struct pci_root_info *info;
 	u32 reg;
 	struct resource *res;
 	u64 start;
 	u64 end;
 	struct range range[RANGE_NUM];
 	u64 val;
 	u32 address;
 	bool found;

 	if (!early_pci_allowed())
 		return -1;

 	found = false;
 	for (i = 0; i < ARRAY_SIZE(pci_probes); i++) {
 		u32 id;
 		u16 device;
 		u16 vendor;

 		bus = pci_probes[i].bus;
 		slot = pci_probes[i].slot;
 		id = read_pci_config(bus, slot, 0, PCI_VENDOR_ID);

 		vendor = id & 0xffff;
 		device = (id>>16) & 0xffff;
 		if (pci_probes[i].vendor == vendor &&
 		    pci_probes[i].device == device) {
 			found = true;
 			break;
 		}
 	}

 	if (!found)
 		return 0;

 	pci_root_num = 0;
 	for (i = 0; i < 4; i++) {
 		int min_bus;
 		int max_bus;
 		reg = read_pci_config(bus, slot, 1, 0xe0 + (i << 2));

 		/* Check if that register is enabled for bus range */
 		if ((reg & 7) != 3)
 			continue;

 		min_bus = (reg >> 16) & 0xff;
 		max_bus = (reg >> 24) & 0xff;
 		node = (reg >> 4) & 0x07;
 #ifdef CONFIG_NUMA
 		for (j = min_bus; j <= max_bus; j++)
 			set_mp_bus_to_node(j, node);
 #endif
 		link = (reg >> 8) & 0x03;

 		info = &pci_root_info[pci_root_num];
 		info->bus_min = min_bus;
 		info->bus_max = max_bus;
 		info->node = node;
 		info->link = link;
 		sprintf(info->name, "PCI Bus #%02x", min_bus);
 		pci_root_num++;
 	}

 	/* get the default node and link for left over res */
 	reg = read_pci_config(bus, slot, 0, 0x60);
 	def_node = (reg >> 8) & 0x07;
 	reg = read_pci_config(bus, slot, 0, 0x64);
 	def_link = (reg >> 8) & 0x03;

 	memset(range, 0, sizeof(range));
 	add_range(range, RANGE_NUM, 0, 0, 0xffff + 1);
 	/* io port resource */
 	for (i = 0; i < 4; i++) {
 		reg = read_pci_config(bus, slot, 1, 0xc0 + (i << 3));
 		if (!(reg & 3))
 			continue;

 		start = reg & 0xfff000;
 		reg = read_pci_config(bus, slot, 1, 0xc4 + (i << 3));
 		node = reg & 0x07;
 		link = (reg >> 4) & 0x03;
 		end = (reg & 0xfff000) | 0xfff;

 		/* find the position */
 		for (j = 0; j < pci_root_num; j++) {
 			info = &pci_root_info[j];
 			if (info->node == node && info->link == link)
 				break;
 		}
 		if (j == pci_root_num)
 			continue; /* not found */

 		info = &pci_root_info[j];
 		printk(KERN_DEBUG "node %d link %d: io port [%llx, %llx]\n",
 		       node, link, start, end);

 		/* kernel only handle 16 bit only */
 		if (end > 0xffff)
 			end = 0xffff;
 		update_res(info, start, end, IORESOURCE_IO, 1);
 		subtract_range(range, RANGE_NUM, start, end + 1);
 	}
 	/* add left over io port range to def node/link, [0, 0xffff] */
 	/* find the position */
 	for (j = 0; j < pci_root_num; j++) {
 		info = &pci_root_info[j];
 		if (info->node == def_node && info->link == def_link)
 			break;
 	}
 	if (j < pci_root_num) {
 		info = &pci_root_info[j];
 		for (i = 0; i < RANGE_NUM; i++) {
 			if (!range[i].end)
 				continue;

 			update_res(info, range[i].start, range[i].end - 1,
 				   IORESOURCE_IO, 1);
 		}
 	}

 	memset(range, 0, sizeof(range));
 	/* 0xfd00000000-0xffffffffff for HT */
 	end = cap_resource((0xfdULL<<32) - 1);
 	end++;
 	add_range(range, RANGE_NUM, 0, 0, end);

 	/* need to take out [0, TOM) for RAM*/
 	address = MSR_K8_TOP_MEM1;
 	rdmsrl(address, val);
 	end = (val & 0xffffff800000ULL);
 	printk(KERN_INFO "TOM: %016llx aka %lldM\n", end, end>>20);
 	if (end < (1ULL<<32))
 		subtract_range(range, RANGE_NUM, 0, end);

 	/* get mmconfig */
 	get_pci_mmcfg_amd_fam10h_range();
 	/* need to take out mmconf range */
 	if (fam10h_mmconf_end) {
 		printk(KERN_DEBUG "Fam 10h mmconf [%llx, %llx]\n", fam10h_mmconf_start, fam10h_mmconf_end);
 		subtract_range(range, RANGE_NUM, fam10h_mmconf_start,
 				 fam10h_mmconf_end + 1);
 	}

 	/* mmio resource */
 	for (i = 0; i < 8; i++) {
 		reg = read_pci_config(bus, slot, 1, 0x80 + (i << 3));
 		if (!(reg & 3))
 			continue;

 		start = reg & 0xffffff00; /* 39:16 on 31:8*/
 		start <<= 8;
 		reg = read_pci_config(bus, slot, 1, 0x84 + (i << 3));
 		node = reg & 0x07;
 		link = (reg >> 4) & 0x03;
 		end = (reg & 0xffffff00);
 		end <<= 8;
 		end |= 0xffff;

 		/* find the position */
 		for (j = 0; j < pci_root_num; j++) {
 			info = &pci_root_info[j];
 			if (info->node == node && info->link == link)
 				break;
 		}
 		if (j == pci_root_num)
 			continue; /* not found */

 		info = &pci_root_info[j];

 		printk(KERN_DEBUG "node %d link %d: mmio [%llx, %llx]",
 		       node, link, start, end);
 		/*
 		 * some sick allocation would have range overlap with fam10h
 		 * mmconf range, so need to update start and end.
 		 */
 		if (fam10h_mmconf_end) {
 			int changed = 0;
 			u64 endx = 0;
 			if (start >= fam10h_mmconf_start &&
 			    start <= fam10h_mmconf_end) {
 				start = fam10h_mmconf_end + 1;
 				changed = 1;
 			}

 			if (end >= fam10h_mmconf_start &&
 			    end <= fam10h_mmconf_end) {
 				end = fam10h_mmconf_start - 1;
 				changed = 1;
 			}

 			if (start < fam10h_mmconf_start &&
 			    end > fam10h_mmconf_end) {
 				/* we got a hole */
 				endx = fam10h_mmconf_start - 1;
 				update_res(info, start, endx, IORESOURCE_MEM, 0);
 				subtract_range(range, RANGE_NUM, start,
 						 endx + 1);
 				printk(KERN_CONT " ==> [%llx, %llx]", start, endx);
 				start = fam10h_mmconf_end + 1;
 				changed = 1;
 			}
 			if (changed) {
 				if (start <= end) {
 					printk(KERN_CONT " %s [%llx, %llx]", endx ? "and" : "==>", start, end);
 				} else {
 					printk(KERN_CONT "%s\n", endx?"":" ==> none");
 					continue;
 				}
 			}
 		}

 		update_res(info, cap_resource(start), cap_resource(end),
 				 IORESOURCE_MEM, 1);
 		subtract_range(range, RANGE_NUM, start, end + 1);
 		printk(KERN_CONT "\n");
 	}

 	/* need to take out [4G, TOM2) for RAM*/
 	/* SYS_CFG */
 	address = MSR_K8_SYSCFG;
 	rdmsrl(address, val);
 	/* TOP_MEM2 is enabled? */
 	if (val & (1<<21)) {
 		/* TOP_MEM2 */
 		address = MSR_K8_TOP_MEM2;
 		rdmsrl(address, val);
 		end = (val & 0xffffff800000ULL);
 		printk(KERN_INFO "TOM2: %016llx aka %lldM\n", end, end>>20);
 		subtract_range(range, RANGE_NUM, 1ULL<<32, end);
 	}

 	/*
 	 * add left over mmio range to def node/link ?
 	 * that is tricky, just record range in from start_min to 4G
 	 */
 	for (j = 0; j < pci_root_num; j++) {
 		info = &pci_root_info[j];
 		if (info->node == def_node && info->link == def_link)
 			break;
 	}
 	if (j < pci_root_num) {
 		info = &pci_root_info[j];

 		for (i = 0; i < RANGE_NUM; i++) {
 			if (!range[i].end)
 				continue;

 			update_res(info, cap_resource(range[i].start),
 				   cap_resource(range[i].end - 1),
 				   IORESOURCE_MEM, 1);
 		}
 	}

 	for (i = 0; i < pci_root_num; i++) {
 		int res_num;
 		int busnum;

 		info = &pci_root_info[i];
 		res_num = info->res_num;
 		busnum = info->bus_min;
 		printk(KERN_DEBUG "bus: [%02x, %02x] on node %x link %x\n",
 		       info->bus_min, info->bus_max, info->node, info->link);
 		for (j = 0; j < res_num; j++) {
 			res = &info->res[j];
 			printk(KERN_DEBUG "bus: %02x index %x %pR\n",
 				       busnum, j, res);
 		}
 	}

 	return 0;
 }

 #define ENABLE_CF8_EXT_CFG      (1ULL << 46)

 static void enable_pci_io_ecs(void *unused)
 {
 	u64 reg;
 	rdmsrl(MSR_AMD64_NB_CFG, reg);
 	if (!(reg & ENABLE_CF8_EXT_CFG)) {
 		reg |= ENABLE_CF8_EXT_CFG;
 		wrmsrl(MSR_AMD64_NB_CFG, reg);
 	}
 }

 static int __cpuinit amd_cpu_notify(struct notifier_block *self,
 				    unsigned long action, void *hcpu)
 {
 	int cpu = (long)hcpu;
 	switch (action) {
 	case CPU_ONLINE:
 	case CPU_ONLINE_FROZEN:
 		smp_call_function_single(cpu, enable_pci_io_ecs, NULL, 0);
 		break;
 	default:
 		break;
 	}
 	return NOTIFY_OK;
 }

 static struct notifier_block __cpuinitdata amd_cpu_notifier = {
 	.notifier_call	= amd_cpu_notify,
 };

 static int __init pci_io_ecs_init(void)
 {
 	int cpu;

 	/* assume all cpus from fam10h have IO ECS */
         if (boot_cpu_data.x86 < 0x10)
 		return 0;

 	register_cpu_notifier(&amd_cpu_notifier);
 	for_each_online_cpu(cpu)
 		amd_cpu_notify(&amd_cpu_notifier, (unsigned long)CPU_ONLINE,
 			       (void *)(long)cpu);
 	pci_probe |= PCI_HAS_IO_ECS;

 	return 0;
 }

 static int __init amd_postcore_init(void)
 {
 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
 		return 0;

 	early_fill_mp_bus_info();
 	pci_io_ecs_init();

 	return 0;
 }

 postcore_initcall(amd_postcore_init);
	#include <linux/init.h>
	#include <linux/pci.h>
	#include <linux/topology.h>
	#include <linux/cpu.h>
	#include <linux/range.h>

	#include <asm/pci_x86.h>

	#include <asm/pci-direct.h>

	#include "bus_numa.h"

	/*
	* This discovers the pcibus <-> node mapping on AMD K8.
	* also get peer root bus resource for io,mmio
	*/

	struct pci_hostbridge_probe {
	u32 bus;
	u32 slot;
	u32 vendor;
	u32 device;
	};

	static struct pci_hostbridge_probe pci_probes[] __initdata = {
	{ 0, 0x18, PCI_VENDOR_ID_AMD, 0x1100 },
	{ 0, 0x18, PCI_VENDOR_ID_AMD, 0x1200 },
	{ 0xff, 0, PCI_VENDOR_ID_AMD, 0x1200 },
	{ 0, 0x18, PCI_VENDOR_ID_AMD, 0x1300 },
	};

	static u64 __initdata fam10h_mmconf_start;
	static u64 __initdata fam10h_mmconf_end;
	static void __init get_pci_mmcfg_amd_fam10h_range(void)
	{
	u32 address;
	u64 base, msr;
	unsigned segn_busn_bits;

	/* assume all cpus from fam10h have mmconf */
	if (boot_cpu_data.x86 < 0x10)
	return;

	address = MSR_FAM10H_MMIO_CONF_BASE;
	rdmsrl(address, msr);

	/* mmconfig is not enable */
	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
	return;

	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);

	segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
	FAM10H_MMIO_CONF_BUSRANGE_MASK;

	fam10h_mmconf_start = base;
	fam10h_mmconf_end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
	}

	#define RANGE_NUM 16

	/**
	* 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
	*/
	static int __init early_fill_mp_bus_info(void)
	{
	int i;
	int j;
	unsigned bus;
	unsigned slot;
	int node;
	int link;
	int def_node;
	int def_link;
	struct pci_root_info *info;
	u32 reg;
	struct resource *res;
	u64 start;
	u64 end;
	struct range range[RANGE_NUM];
	u64 val;
	u32 address;
	bool found;

	if (!early_pci_allowed())
	return -1;

	found = false;
	for (i = 0; i < ARRAY_SIZE(pci_probes); i++) {
	u32 id;
	u16 device;
	u16 vendor;

	bus = pci_probes[i].bus;
	slot = pci_probes[i].slot;
	id = read_pci_config(bus, slot, 0, PCI_VENDOR_ID);

	vendor = id & 0xffff;
	device = (id>>16) & 0xffff;
	if (pci_probes[i].vendor == vendor &&
	pci_probes[i].device == device) {
	found = true;
	break;
	}
	}

	if (!found)
	return 0;

	pci_root_num = 0;
	for (i = 0; i < 4; i++) {
	int min_bus;
	int max_bus;
	reg = read_pci_config(bus, slot, 1, 0xe0 + (i << 2));

	/* Check if that register is enabled for bus range */
	if ((reg & 7) != 3)
	continue;

	min_bus = (reg >> 16) & 0xff;
	max_bus = (reg >> 24) & 0xff;
	node = (reg >> 4) & 0x07;
	#ifdef CONFIG_NUMA
	for (j = min_bus; j <= max_bus; j++)
	set_mp_bus_to_node(j, node);
	#endif
	link = (reg >> 8) & 0x03;

	info = &pci_root_info[pci_root_num];
	info->bus_min = min_bus;
	info->bus_max = max_bus;
	info->node = node;
	info->link = link;
	sprintf(info->name, "PCI Bus #%02x", min_bus);
	pci_root_num++;
	}

	/* get the default node and link for left over res */
	reg = read_pci_config(bus, slot, 0, 0x60);
	def_node = (reg >> 8) & 0x07;
	reg = read_pci_config(bus, slot, 0, 0x64);
	def_link = (reg >> 8) & 0x03;

	memset(range, 0, sizeof(range));
	add_range(range, RANGE_NUM, 0, 0, 0xffff + 1);
	/* io port resource */
	for (i = 0; i < 4; i++) {
	reg = read_pci_config(bus, slot, 1, 0xc0 + (i << 3));
	if (!(reg & 3))
	continue;

	start = reg & 0xfff000;
	reg = read_pci_config(bus, slot, 1, 0xc4 + (i << 3));
	node = reg & 0x07;
	link = (reg >> 4) & 0x03;
	end = (reg & 0xfff000) \| 0xfff;

	/* find the position */
	for (j = 0; j < pci_root_num; j++) {
	info = &pci_root_info[j];
	if (info->node == node && info->link == link)
	break;
	}
	if (j == pci_root_num)
	continue; /* not found */

	info = &pci_root_info[j];
	printk(KERN_DEBUG "node %d link %d: io port [%llx, %llx]\n",
	node, link, start, end);

	/* kernel only handle 16 bit only */
	if (end > 0xffff)
	end = 0xffff;
	update_res(info, start, end, IORESOURCE_IO, 1);
	subtract_range(range, RANGE_NUM, start, end + 1);
	}
	/* add left over io port range to def node/link, [0, 0xffff] */
	/* find the position */
	for (j = 0; j < pci_root_num; j++) {
	info = &pci_root_info[j];
	if (info->node == def_node && info->link == def_link)
	break;
	}
	if (j < pci_root_num) {
	info = &pci_root_info[j];
	for (i = 0; i < RANGE_NUM; i++) {
	if (!range[i].end)
	continue;

	update_res(info, range[i].start, range[i].end - 1,
	IORESOURCE_IO, 1);
	}
	}

	memset(range, 0, sizeof(range));
	/* 0xfd00000000-0xffffffffff for HT */
	end = cap_resource((0xfdULL<<32) - 1);
	end++;
	add_range(range, RANGE_NUM, 0, 0, end);

	/* need to take out [0, TOM) for RAM*/
	address = MSR_K8_TOP_MEM1;
	rdmsrl(address, val);
	end = (val & 0xffffff800000ULL);
	printk(KERN_INFO "TOM: %016llx aka %lldM\n", end, end>>20);
	if (end < (1ULL<<32))
	subtract_range(range, RANGE_NUM, 0, end);

	/* get mmconfig */
	get_pci_mmcfg_amd_fam10h_range();
	/* need to take out mmconf range */
	if (fam10h_mmconf_end) {
	printk(KERN_DEBUG "Fam 10h mmconf [%llx, %llx]\n", fam10h_mmconf_start, fam10h_mmconf_end);
	subtract_range(range, RANGE_NUM, fam10h_mmconf_start,
	fam10h_mmconf_end + 1);
	}

	/* mmio resource */
	for (i = 0; i < 8; i++) {
	reg = read_pci_config(bus, slot, 1, 0x80 + (i << 3));
	if (!(reg & 3))
	continue;

	start = reg & 0xffffff00; /* 39:16 on 31:8*/
	start <<= 8;
	reg = read_pci_config(bus, slot, 1, 0x84 + (i << 3));
	node = reg & 0x07;
	link = (reg >> 4) & 0x03;
	end = (reg & 0xffffff00);
	end <<= 8;
	end \|= 0xffff;

	/* find the position */
	for (j = 0; j < pci_root_num; j++) {
	info = &pci_root_info[j];
	if (info->node == node && info->link == link)
	break;
	}
	if (j == pci_root_num)
	continue; /* not found */

	info = &pci_root_info[j];

	printk(KERN_DEBUG "node %d link %d: mmio [%llx, %llx]",
	node, link, start, end);
	/*
	* some sick allocation would have range overlap with fam10h
	* mmconf range, so need to update start and end.
	*/
	if (fam10h_mmconf_end) {
	int changed = 0;
	u64 endx = 0;
	if (start >= fam10h_mmconf_start &&
	start <= fam10h_mmconf_end) {
	start = fam10h_mmconf_end + 1;
	changed = 1;
	}

	if (end >= fam10h_mmconf_start &&
	end <= fam10h_mmconf_end) {
	end = fam10h_mmconf_start - 1;
	changed = 1;
	}

	if (start < fam10h_mmconf_start &&
	end > fam10h_mmconf_end) {
	/* we got a hole */
	endx = fam10h_mmconf_start - 1;
	update_res(info, start, endx, IORESOURCE_MEM, 0);
	subtract_range(range, RANGE_NUM, start,
	endx + 1);
	printk(KERN_CONT " ==> [%llx, %llx]", start, endx);
	start = fam10h_mmconf_end + 1;
	changed = 1;
	}
	if (changed) {
	if (start <= end) {
	printk(KERN_CONT " %s [%llx, %llx]", endx ? "and" : "==>", start, end);
	} else {
	printk(KERN_CONT "%s\n", endx?"":" ==> none");
	continue;
	}
	}
	}

	update_res(info, cap_resource(start), cap_resource(end),
	IORESOURCE_MEM, 1);
	subtract_range(range, RANGE_NUM, start, end + 1);
	printk(KERN_CONT "\n");
	}

	/* need to take out [4G, TOM2) for RAM*/
	/* SYS_CFG */
	address = MSR_K8_SYSCFG;
	rdmsrl(address, val);
	/* TOP_MEM2 is enabled? */
	if (val & (1<<21)) {
	/* TOP_MEM2 */
	address = MSR_K8_TOP_MEM2;
	rdmsrl(address, val);
	end = (val & 0xffffff800000ULL);
	printk(KERN_INFO "TOM2: %016llx aka %lldM\n", end, end>>20);
	subtract_range(range, RANGE_NUM, 1ULL<<32, end);
	}

	/*
	* add left over mmio range to def node/link ?
	* that is tricky, just record range in from start_min to 4G
	*/
	for (j = 0; j < pci_root_num; j++) {
	info = &pci_root_info[j];
	if (info->node == def_node && info->link == def_link)
	break;
	}
	if (j < pci_root_num) {
	info = &pci_root_info[j];

	for (i = 0; i < RANGE_NUM; i++) {
	if (!range[i].end)
	continue;

	update_res(info, cap_resource(range[i].start),
	cap_resource(range[i].end - 1),
	IORESOURCE_MEM, 1);
	}
	}

	for (i = 0; i < pci_root_num; i++) {
	int res_num;
	int busnum;

	info = &pci_root_info[i];
	res_num = info->res_num;
	busnum = info->bus_min;
	printk(KERN_DEBUG "bus: [%02x, %02x] on node %x link %x\n",
	info->bus_min, info->bus_max, info->node, info->link);
	for (j = 0; j < res_num; j++) {
	res = &info->res[j];
	printk(KERN_DEBUG "bus: %02x index %x %pR\n",
	busnum, j, res);
	}
	}

	return 0;
	}

	#define ENABLE_CF8_EXT_CFG (1ULL << 46)

	static void enable_pci_io_ecs(void *unused)
	{
	u64 reg;
	rdmsrl(MSR_AMD64_NB_CFG, reg);
	if (!(reg & ENABLE_CF8_EXT_CFG)) {
	reg \|= ENABLE_CF8_EXT_CFG;
	wrmsrl(MSR_AMD64_NB_CFG, reg);
	}
	}

	static int __cpuinit amd_cpu_notify(struct notifier_block *self,
	unsigned long action, void *hcpu)
	{
	int cpu = (long)hcpu;
	switch (action) {
	case CPU_ONLINE:
	case CPU_ONLINE_FROZEN:
	smp_call_function_single(cpu, enable_pci_io_ecs, NULL, 0);
	break;
	default:
	break;
	}
	return NOTIFY_OK;
	}

	static struct notifier_block __cpuinitdata amd_cpu_notifier = {
	.notifier_call = amd_cpu_notify,
	};

	static int __init pci_io_ecs_init(void)
	{
	int cpu;

	/* assume all cpus from fam10h have IO ECS */
	if (boot_cpu_data.x86 < 0x10)
	return 0;

	register_cpu_notifier(&amd_cpu_notifier);
	for_each_online_cpu(cpu)
	amd_cpu_notify(&amd_cpu_notifier, (unsigned long)CPU_ONLINE,
	(void *)(long)cpu);
	pci_probe \|= PCI_HAS_IO_ECS;

	return 0;
	}

	static int __init amd_postcore_init(void)
	{
	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
	return 0;

	early_fill_mp_bus_info();
	pci_io_ecs_init();

	return 0;
	}

	postcore_initcall(amd_postcore_init);