linux-bl808/arch/x86/pci/amd_bus.c
Srivatsa S. Bhat 9f668f6661 x86, pci, amd-bus: Fix CPU hotplug callback registration
Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:

	get_online_cpus();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	register_cpu_notifier(&foobar_cpu_notifier);

	put_online_cpus();

This is wrong, since it is prone to ABBA deadlocks involving the
cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
with CPU hotplug operations).

Instead, the correct and race-free way of performing the callback
registration is:

	cpu_notifier_register_begin();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	/* Note the use of the double underscored version of the API */
	__register_cpu_notifier(&foobar_cpu_notifier);

	cpu_notifier_register_done();

Fix the amd-bus code in x86 by using this latter form of callback
registration.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-20 13:43:43 +01:00

406 lines
9.3 KiB
C

#include <linux/init.h>
#include <linux/pci.h>
#include <linux/topology.h>
#include <linux/cpu.h>
#include <linux/range.h>
#include <asm/amd_nb.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 },
};
#define RANGE_NUM 16
static struct pci_root_info __init *find_pci_root_info(int node, int link)
{
struct pci_root_info *info;
/* find the position */
list_for_each_entry(info, &pci_root_infos, list)
if (info->node == node && info->link == link)
return info;
return NULL;
}
static void __init set_mp_bus_range_to_node(int min_bus, int max_bus, int node)
{
#ifdef CONFIG_NUMA
int j;
for (j = min_bus; j <= max_bus; j++)
set_mp_bus_to_node(j, 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
*/
static int __init early_fill_mp_bus_info(void)
{
int i;
unsigned bus;
unsigned slot;
int node;
int link;
int def_node;
int def_link;
struct pci_root_info *info;
u32 reg;
u64 start;
u64 end;
struct range range[RANGE_NUM];
u64 val;
u32 address;
bool found;
struct resource fam10h_mmconf_res, *fam10h_mmconf;
u64 fam10h_mmconf_start;
u64 fam10h_mmconf_end;
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;
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;
set_mp_bus_range_to_node(min_bus, max_bus, node);
link = (reg >> 8) & 0x03;
info = alloc_pci_root_info(min_bus, max_bus, node, link);
}
/* 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;
info = find_pci_root_info(node, link);
if (!info)
continue; /* not found */
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 */
info = find_pci_root_info(def_node, def_link);
if (info) {
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 */
fam10h_mmconf = amd_get_mmconfig_range(&fam10h_mmconf_res);
/* need to take out mmconf range */
if (fam10h_mmconf) {
printk(KERN_DEBUG "Fam 10h mmconf %pR\n", fam10h_mmconf);
fam10h_mmconf_start = fam10h_mmconf->start;
fam10h_mmconf_end = fam10h_mmconf->end;
subtract_range(range, RANGE_NUM, fam10h_mmconf_start,
fam10h_mmconf_end + 1);
} else {
fam10h_mmconf_start = 0;
fam10h_mmconf_end = 0;
}
/* 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;
info = find_pci_root_info(node, link);
if (!info)
continue;
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
*/
info = find_pci_root_info(def_node, def_link);
if (info) {
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);
}
}
list_for_each_entry(info, &pci_root_infos, list) {
int busnum;
struct pci_root_res *root_res;
busnum = info->busn.start;
printk(KERN_DEBUG "bus: %pR on node %x link %x\n",
&info->busn, info->node, info->link);
list_for_each_entry(root_res, &info->resources, list)
printk(KERN_DEBUG "bus: %02x %pR\n",
busnum, &root_res->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 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 amd_cpu_notifier = {
.notifier_call = amd_cpu_notify,
};
static void __init pci_enable_pci_io_ecs(void)
{
#ifdef CONFIG_AMD_NB
unsigned int i, n;
for (n = i = 0; !n && amd_nb_bus_dev_ranges[i].dev_limit; ++i) {
u8 bus = amd_nb_bus_dev_ranges[i].bus;
u8 slot = amd_nb_bus_dev_ranges[i].dev_base;
u8 limit = amd_nb_bus_dev_ranges[i].dev_limit;
for (; slot < limit; ++slot) {
u32 val = read_pci_config(bus, slot, 3, 0);
if (!early_is_amd_nb(val))
continue;
val = read_pci_config(bus, slot, 3, 0x8c);
if (!(val & (ENABLE_CF8_EXT_CFG >> 32))) {
val |= ENABLE_CF8_EXT_CFG >> 32;
write_pci_config(bus, slot, 3, 0x8c, val);
}
++n;
}
}
#endif
}
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;
/* Try the PCI method first. */
if (early_pci_allowed())
pci_enable_pci_io_ecs();
cpu_notifier_register_begin();
for_each_online_cpu(cpu)
amd_cpu_notify(&amd_cpu_notifier, (unsigned long)CPU_ONLINE,
(void *)(long)cpu);
__register_cpu_notifier(&amd_cpu_notifier);
cpu_notifier_register_done();
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);