linux/drivers/pci/probe.c
Rafael J. Wysocki 6c0cc950ae ACPI / PCI: Set root bridge ACPI handle in advance
The ACPI handles of PCI root bridges need to be known to
acpi_bind_one(), so that it can create the appropriate
"firmware_node" and "physical_node" files for them, but currently
the way it gets to know those handles is not exactly straightforward
(to put it lightly).

This is how it works, roughly:

  1. acpi_bus_scan() finds the handle of a PCI root bridge,
     creates a struct acpi_device object for it and passes that
     object to acpi_pci_root_add().

  2. acpi_pci_root_add() creates a struct acpi_pci_root object,
     populates its "device" field with its argument's address
     (device->handle is the ACPI handle found in step 1).

  3. The struct acpi_pci_root object created in step 2 is passed
     to pci_acpi_scan_root() and used to get resources that are
     passed to pci_create_root_bus().

  4. pci_create_root_bus() creates a struct pci_host_bridge object
     and passes its "dev" member to device_register().

  5. platform_notify(), which for systems with ACPI is set to
     acpi_platform_notify(), is called.

So far, so good.  Now it starts to be "interesting".

  6. acpi_find_bridge_device() is used to find the ACPI handle of
     the given device (which is the PCI root bridge) and executes
     acpi_pci_find_root_bridge(), among other things, for the
     given device object.

  7. acpi_pci_find_root_bridge() uses the name (sic!) of the given
     device object to extract the segment and bus numbers of the PCI
     root bridge and passes them to acpi_get_pci_rootbridge_handle().

  8. acpi_get_pci_rootbridge_handle() browses the list of ACPI PCI
     root bridges and finds the one that matches the given segment
     and bus numbers.  Its handle is then used to initialize the
     ACPI handle of the PCI root bridge's device object by
     acpi_bind_one().  However, this is *exactly* the ACPI handle we
     started with in step 1.

Needless to say, this is quite embarassing, but it may be avoided
thanks to commit f3fd0c8 (ACPI: Allow ACPI handles of devices to be
initialized in advance), which makes it possible to initialize the
ACPI handle of a device before passing it to device_register().

Accordingly, add a new __weak routine, pcibios_root_bridge_prepare(),
defaulting to an empty implementation that can be replaced by the
interested architecutres (x86 and ia64 at the moment) with functions
that will set the root bridge's ACPI handle before its dev member is
passed to device_register().  Make both x86 and ia64 provide such
implementations of pcibios_root_bridge_prepare() and remove
acpi_pci_find_root_bridge() and acpi_get_pci_rootbridge_handle() that
aren't necessary any more.

Included is a fix for breakage on systems with non-ACPI PCI host
bridges from Bjorn Helgaas.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-01-13 17:14:28 -07:00

1959 lines
50 KiB
C

/*
* probe.c - PCI detection and setup code
*/
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/cpumask.h>
#include <linux/pci-aspm.h>
#include <asm-generic/pci-bridge.h>
#include "pci.h"
#define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
#define CARDBUS_RESERVE_BUSNR 3
struct resource busn_resource = {
.name = "PCI busn",
.start = 0,
.end = 255,
.flags = IORESOURCE_BUS,
};
/* Ugh. Need to stop exporting this to modules. */
LIST_HEAD(pci_root_buses);
EXPORT_SYMBOL(pci_root_buses);
static LIST_HEAD(pci_domain_busn_res_list);
struct pci_domain_busn_res {
struct list_head list;
struct resource res;
int domain_nr;
};
static struct resource *get_pci_domain_busn_res(int domain_nr)
{
struct pci_domain_busn_res *r;
list_for_each_entry(r, &pci_domain_busn_res_list, list)
if (r->domain_nr == domain_nr)
return &r->res;
r = kzalloc(sizeof(*r), GFP_KERNEL);
if (!r)
return NULL;
r->domain_nr = domain_nr;
r->res.start = 0;
r->res.end = 0xff;
r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
list_add_tail(&r->list, &pci_domain_busn_res_list);
return &r->res;
}
static int find_anything(struct device *dev, void *data)
{
return 1;
}
/*
* Some device drivers need know if pci is initiated.
* Basically, we think pci is not initiated when there
* is no device to be found on the pci_bus_type.
*/
int no_pci_devices(void)
{
struct device *dev;
int no_devices;
dev = bus_find_device(&pci_bus_type, NULL, NULL, find_anything);
no_devices = (dev == NULL);
put_device(dev);
return no_devices;
}
EXPORT_SYMBOL(no_pci_devices);
/*
* PCI Bus Class
*/
static void release_pcibus_dev(struct device *dev)
{
struct pci_bus *pci_bus = to_pci_bus(dev);
if (pci_bus->bridge)
put_device(pci_bus->bridge);
pci_bus_remove_resources(pci_bus);
pci_release_bus_of_node(pci_bus);
kfree(pci_bus);
}
static struct class pcibus_class = {
.name = "pci_bus",
.dev_release = &release_pcibus_dev,
.dev_attrs = pcibus_dev_attrs,
};
static int __init pcibus_class_init(void)
{
return class_register(&pcibus_class);
}
postcore_initcall(pcibus_class_init);
static u64 pci_size(u64 base, u64 maxbase, u64 mask)
{
u64 size = mask & maxbase; /* Find the significant bits */
if (!size)
return 0;
/* Get the lowest of them to find the decode size, and
from that the extent. */
size = (size & ~(size-1)) - 1;
/* base == maxbase can be valid only if the BAR has
already been programmed with all 1s. */
if (base == maxbase && ((base | size) & mask) != mask)
return 0;
return size;
}
static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
{
u32 mem_type;
unsigned long flags;
if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
flags |= IORESOURCE_IO;
return flags;
}
flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
flags |= IORESOURCE_MEM;
if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
flags |= IORESOURCE_PREFETCH;
mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
switch (mem_type) {
case PCI_BASE_ADDRESS_MEM_TYPE_32:
break;
case PCI_BASE_ADDRESS_MEM_TYPE_1M:
/* 1M mem BAR treated as 32-bit BAR */
break;
case PCI_BASE_ADDRESS_MEM_TYPE_64:
flags |= IORESOURCE_MEM_64;
break;
default:
/* mem unknown type treated as 32-bit BAR */
break;
}
return flags;
}
/**
* pci_read_base - read a PCI BAR
* @dev: the PCI device
* @type: type of the BAR
* @res: resource buffer to be filled in
* @pos: BAR position in the config space
*
* Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
*/
int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
struct resource *res, unsigned int pos)
{
u32 l, sz, mask;
u16 orig_cmd;
struct pci_bus_region region;
bool bar_too_big = false, bar_disabled = false;
mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
/* No printks while decoding is disabled! */
if (!dev->mmio_always_on) {
pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
pci_write_config_word(dev, PCI_COMMAND,
orig_cmd & ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO));
}
res->name = pci_name(dev);
pci_read_config_dword(dev, pos, &l);
pci_write_config_dword(dev, pos, l | mask);
pci_read_config_dword(dev, pos, &sz);
pci_write_config_dword(dev, pos, l);
/*
* All bits set in sz means the device isn't working properly.
* If the BAR isn't implemented, all bits must be 0. If it's a
* memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
* 1 must be clear.
*/
if (!sz || sz == 0xffffffff)
goto fail;
/*
* I don't know how l can have all bits set. Copied from old code.
* Maybe it fixes a bug on some ancient platform.
*/
if (l == 0xffffffff)
l = 0;
if (type == pci_bar_unknown) {
res->flags = decode_bar(dev, l);
res->flags |= IORESOURCE_SIZEALIGN;
if (res->flags & IORESOURCE_IO) {
l &= PCI_BASE_ADDRESS_IO_MASK;
mask = PCI_BASE_ADDRESS_IO_MASK & (u32) IO_SPACE_LIMIT;
} else {
l &= PCI_BASE_ADDRESS_MEM_MASK;
mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
}
} else {
res->flags |= (l & IORESOURCE_ROM_ENABLE);
l &= PCI_ROM_ADDRESS_MASK;
mask = (u32)PCI_ROM_ADDRESS_MASK;
}
if (res->flags & IORESOURCE_MEM_64) {
u64 l64 = l;
u64 sz64 = sz;
u64 mask64 = mask | (u64)~0 << 32;
pci_read_config_dword(dev, pos + 4, &l);
pci_write_config_dword(dev, pos + 4, ~0);
pci_read_config_dword(dev, pos + 4, &sz);
pci_write_config_dword(dev, pos + 4, l);
l64 |= ((u64)l << 32);
sz64 |= ((u64)sz << 32);
sz64 = pci_size(l64, sz64, mask64);
if (!sz64)
goto fail;
if ((sizeof(resource_size_t) < 8) && (sz64 > 0x100000000ULL)) {
bar_too_big = true;
goto fail;
}
if ((sizeof(resource_size_t) < 8) && l) {
/* Address above 32-bit boundary; disable the BAR */
pci_write_config_dword(dev, pos, 0);
pci_write_config_dword(dev, pos + 4, 0);
region.start = 0;
region.end = sz64;
pcibios_bus_to_resource(dev, res, &region);
bar_disabled = true;
} else {
region.start = l64;
region.end = l64 + sz64;
pcibios_bus_to_resource(dev, res, &region);
}
} else {
sz = pci_size(l, sz, mask);
if (!sz)
goto fail;
region.start = l;
region.end = l + sz;
pcibios_bus_to_resource(dev, res, &region);
}
goto out;
fail:
res->flags = 0;
out:
if (!dev->mmio_always_on)
pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
if (bar_too_big)
dev_err(&dev->dev, "reg %x: can't handle 64-bit BAR\n", pos);
if (res->flags && !bar_disabled)
dev_printk(KERN_DEBUG, &dev->dev, "reg %x: %pR\n", pos, res);
return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
}
static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
{
unsigned int pos, reg;
for (pos = 0; pos < howmany; pos++) {
struct resource *res = &dev->resource[pos];
reg = PCI_BASE_ADDRESS_0 + (pos << 2);
pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
}
if (rom) {
struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
dev->rom_base_reg = rom;
res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
IORESOURCE_READONLY | IORESOURCE_CACHEABLE |
IORESOURCE_SIZEALIGN;
__pci_read_base(dev, pci_bar_mem32, res, rom);
}
}
static void pci_read_bridge_io(struct pci_bus *child)
{
struct pci_dev *dev = child->self;
u8 io_base_lo, io_limit_lo;
unsigned long io_mask, io_granularity, base, limit;
struct pci_bus_region region;
struct resource *res;
io_mask = PCI_IO_RANGE_MASK;
io_granularity = 0x1000;
if (dev->io_window_1k) {
/* Support 1K I/O space granularity */
io_mask = PCI_IO_1K_RANGE_MASK;
io_granularity = 0x400;
}
res = child->resource[0];
pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
base = (io_base_lo & io_mask) << 8;
limit = (io_limit_lo & io_mask) << 8;
if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
u16 io_base_hi, io_limit_hi;
pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
base |= ((unsigned long) io_base_hi << 16);
limit |= ((unsigned long) io_limit_hi << 16);
}
if (base <= limit) {
res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
region.start = base;
region.end = limit + io_granularity - 1;
pcibios_bus_to_resource(dev, res, &region);
dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
}
}
static void pci_read_bridge_mmio(struct pci_bus *child)
{
struct pci_dev *dev = child->self;
u16 mem_base_lo, mem_limit_lo;
unsigned long base, limit;
struct pci_bus_region region;
struct resource *res;
res = child->resource[1];
pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
if (base <= limit) {
res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
region.start = base;
region.end = limit + 0xfffff;
pcibios_bus_to_resource(dev, res, &region);
dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
}
}
static void pci_read_bridge_mmio_pref(struct pci_bus *child)
{
struct pci_dev *dev = child->self;
u16 mem_base_lo, mem_limit_lo;
unsigned long base, limit;
struct pci_bus_region region;
struct resource *res;
res = child->resource[2];
pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
base = ((unsigned long) mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
limit = ((unsigned long) mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
u32 mem_base_hi, mem_limit_hi;
pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
/*
* Some bridges set the base > limit by default, and some
* (broken) BIOSes do not initialize them. If we find
* this, just assume they are not being used.
*/
if (mem_base_hi <= mem_limit_hi) {
#if BITS_PER_LONG == 64
base |= ((unsigned long) mem_base_hi) << 32;
limit |= ((unsigned long) mem_limit_hi) << 32;
#else
if (mem_base_hi || mem_limit_hi) {
dev_err(&dev->dev, "can't handle 64-bit "
"address space for bridge\n");
return;
}
#endif
}
}
if (base <= limit) {
res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
IORESOURCE_MEM | IORESOURCE_PREFETCH;
if (res->flags & PCI_PREF_RANGE_TYPE_64)
res->flags |= IORESOURCE_MEM_64;
region.start = base;
region.end = limit + 0xfffff;
pcibios_bus_to_resource(dev, res, &region);
dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
}
}
void pci_read_bridge_bases(struct pci_bus *child)
{
struct pci_dev *dev = child->self;
struct resource *res;
int i;
if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
return;
dev_info(&dev->dev, "PCI bridge to %pR%s\n",
&child->busn_res,
dev->transparent ? " (subtractive decode)" : "");
pci_bus_remove_resources(child);
for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
pci_read_bridge_io(child);
pci_read_bridge_mmio(child);
pci_read_bridge_mmio_pref(child);
if (dev->transparent) {
pci_bus_for_each_resource(child->parent, res, i) {
if (res) {
pci_bus_add_resource(child, res,
PCI_SUBTRACTIVE_DECODE);
dev_printk(KERN_DEBUG, &dev->dev,
" bridge window %pR (subtractive decode)\n",
res);
}
}
}
}
static struct pci_bus * pci_alloc_bus(void)
{
struct pci_bus *b;
b = kzalloc(sizeof(*b), GFP_KERNEL);
if (b) {
INIT_LIST_HEAD(&b->node);
INIT_LIST_HEAD(&b->children);
INIT_LIST_HEAD(&b->devices);
INIT_LIST_HEAD(&b->slots);
INIT_LIST_HEAD(&b->resources);
b->max_bus_speed = PCI_SPEED_UNKNOWN;
b->cur_bus_speed = PCI_SPEED_UNKNOWN;
}
return b;
}
static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b)
{
struct pci_host_bridge *bridge;
bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
if (bridge) {
INIT_LIST_HEAD(&bridge->windows);
bridge->bus = b;
}
return bridge;
}
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 */
PCIE_SPEED_5_0GT, /* 2 */
PCIE_SPEED_8_0GT, /* 3 */
PCI_SPEED_UNKNOWN, /* 4 */
PCI_SPEED_UNKNOWN, /* 5 */
PCI_SPEED_UNKNOWN, /* 6 */
PCI_SPEED_UNKNOWN, /* 7 */
PCI_SPEED_UNKNOWN, /* 8 */
PCI_SPEED_UNKNOWN, /* 9 */
PCI_SPEED_UNKNOWN, /* A */
PCI_SPEED_UNKNOWN, /* B */
PCI_SPEED_UNKNOWN, /* C */
PCI_SPEED_UNKNOWN, /* D */
PCI_SPEED_UNKNOWN, /* E */
PCI_SPEED_UNKNOWN /* F */
};
void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
{
bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS];
}
EXPORT_SYMBOL_GPL(pcie_update_link_speed);
static unsigned char agp_speeds[] = {
AGP_UNKNOWN,
AGP_1X,
AGP_2X,
AGP_4X,
AGP_8X
};
static enum pci_bus_speed agp_speed(int agp3, int agpstat)
{
int index = 0;
if (agpstat & 4)
index = 3;
else if (agpstat & 2)
index = 2;
else if (agpstat & 1)
index = 1;
else
goto out;
if (agp3) {
index += 2;
if (index == 5)
index = 0;
}
out:
return agp_speeds[index];
}
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_AGP);
if (!pos)
pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
if (pos) {
u32 agpstat, agpcmd;
pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
}
pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
if (pos) {
u16 status;
enum pci_bus_speed max;
pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
&status);
if (status & PCI_X_SSTATUS_533MHZ) {
max = PCI_SPEED_133MHz_PCIX_533;
} else if (status & PCI_X_SSTATUS_266MHZ) {
max = PCI_SPEED_133MHz_PCIX_266;
} else if (status & PCI_X_SSTATUS_133MHZ) {
if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2) {
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 & PCI_X_SSTATUS_FREQ) >> 6];
return;
}
pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
if (pos) {
u32 linkcap;
u16 linksta;
pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
pcie_capability_read_word(bridge, 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)
{
struct pci_bus *child;
int i;
/*
* Allocate a new bus, and inherit stuff from the parent..
*/
child = pci_alloc_bus();
if (!child)
return NULL;
child->parent = parent;
child->ops = parent->ops;
child->sysdata = parent->sysdata;
child->bus_flags = parent->bus_flags;
/* initialize some portions of the bus device, but don't register it
* now as the parent is not properly set up yet. This device will get
* registered later in pci_bus_add_devices()
*/
child->dev.class = &pcibus_class;
dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
/*
* Set up the primary, secondary and subordinate
* bus numbers.
*/
child->number = child->busn_res.start = busnr;
child->primary = parent->busn_res.start;
child->busn_res.end = 0xff;
if (!bridge)
return child;
child->self = bridge;
child->bridge = get_device(&bridge->dev);
pci_set_bus_of_node(child);
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];
child->resource[i]->name = child->name;
}
bridge->subordinate = child;
return child;
}
struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr)
{
struct pci_bus *child;
child = pci_alloc_child_bus(parent, dev, busnr);
if (child) {
down_write(&pci_bus_sem);
list_add_tail(&child->node, &parent->children);
up_write(&pci_bus_sem);
}
return child;
}
static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
{
struct pci_bus *parent = child->parent;
/* Attempts to fix that up are really dangerous unless
we're going to re-assign all bus numbers. */
if (!pcibios_assign_all_busses())
return;
while (parent->parent && parent->busn_res.end < max) {
parent->busn_res.end = max;
pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);
parent = parent->parent;
}
}
/*
* If it's a bridge, configure it and scan the bus behind it.
* For CardBus bridges, we don't scan behind as the devices will
* be handled by the bridge driver itself.
*
* We need to process bridges in two passes -- first we scan those
* already configured by the BIOS and after we are done with all of
* them, we proceed to assigning numbers to the remaining buses in
* order to avoid overlaps between old and new bus numbers.
*/
int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
{
struct pci_bus *child;
int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
u32 buses, i, j = 0;
u16 bctl;
u8 primary, secondary, subordinate;
int broken = 0;
pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
primary = buses & 0xFF;
secondary = (buses >> 8) & 0xFF;
subordinate = (buses >> 16) & 0xFF;
dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
secondary, subordinate, pass);
if (!primary && (primary != bus->number) && secondary && subordinate) {
dev_warn(&dev->dev, "Primary bus is hard wired to 0\n");
primary = bus->number;
}
/* Check if setup is sensible at all */
if (!pass &&
(primary != bus->number || secondary <= bus->number ||
secondary > subordinate)) {
dev_info(&dev->dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
secondary, subordinate);
broken = 1;
}
/* Disable MasterAbortMode during probing to avoid reporting
of bus errors (in some architectures) */
pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
!is_cardbus && !broken) {
unsigned int cmax;
/*
* Bus already configured by firmware, process it in the first
* pass and just note the configuration.
*/
if (pass)
goto out;
/*
* If we already got to this bus through a different bridge,
* don't re-add it. This can happen with the i450NX chipset.
*
* However, we continue to descend down the hierarchy and
* scan remaining child buses.
*/
child = pci_find_bus(pci_domain_nr(bus), secondary);
if (!child) {
child = pci_add_new_bus(bus, dev, secondary);
if (!child)
goto out;
child->primary = primary;
pci_bus_insert_busn_res(child, secondary, subordinate);
child->bridge_ctl = bctl;
}
cmax = pci_scan_child_bus(child);
if (cmax > max)
max = cmax;
if (child->busn_res.end > max)
max = child->busn_res.end;
} else {
/*
* We need to assign a number to this bus which we always
* do in the second pass.
*/
if (!pass) {
if (pcibios_assign_all_busses() || broken)
/* Temporarily disable forwarding of the
configuration cycles on all bridges in
this bus segment to avoid possible
conflicts in the second pass between two
bridges programmed with overlapping
bus ranges. */
pci_write_config_dword(dev, PCI_PRIMARY_BUS,
buses & ~0xffffff);
goto out;
}
/* Clear errors */
pci_write_config_word(dev, PCI_STATUS, 0xffff);
/* Prevent assigning a bus number that already exists.
* This can happen when a bridge is hot-plugged, so in
* this case we only re-scan this bus. */
child = pci_find_bus(pci_domain_nr(bus), max+1);
if (!child) {
child = pci_add_new_bus(bus, dev, ++max);
if (!child)
goto out;
pci_bus_insert_busn_res(child, max, 0xff);
}
buses = (buses & 0xff000000)
| ((unsigned int)(child->primary) << 0)
| ((unsigned int)(child->busn_res.start) << 8)
| ((unsigned int)(child->busn_res.end) << 16);
/*
* yenta.c forces a secondary latency timer of 176.
* Copy that behaviour here.
*/
if (is_cardbus) {
buses &= ~0xff000000;
buses |= CARDBUS_LATENCY_TIMER << 24;
}
/*
* We need to blast all three values with a single write.
*/
pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
if (!is_cardbus) {
child->bridge_ctl = bctl;
/*
* Adjust subordinate busnr in parent buses.
* We do this before scanning for children because
* some devices may not be detected if the bios
* was lazy.
*/
pci_fixup_parent_subordinate_busnr(child, max);
/* Now we can scan all subordinate buses... */
max = pci_scan_child_bus(child);
/*
* now fix it up again since we have found
* the real value of max.
*/
pci_fixup_parent_subordinate_busnr(child, max);
} else {
/*
* For CardBus bridges, we leave 4 bus numbers
* as cards with a PCI-to-PCI bridge can be
* inserted later.
*/
for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
struct pci_bus *parent = bus;
if (pci_find_bus(pci_domain_nr(bus),
max+i+1))
break;
while (parent->parent) {
if ((!pcibios_assign_all_busses()) &&
(parent->busn_res.end > max) &&
(parent->busn_res.end <= max+i)) {
j = 1;
}
parent = parent->parent;
}
if (j) {
/*
* Often, there are two cardbus bridges
* -- try to leave one valid bus number
* for each one.
*/
i /= 2;
break;
}
}
max += i;
pci_fixup_parent_subordinate_busnr(child, max);
}
/*
* Set the subordinate bus number to its real value.
*/
pci_bus_update_busn_res_end(child, max);
pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
}
sprintf(child->name,
(is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
pci_domain_nr(bus), child->number);
/* Has only triggered on CardBus, fixup is in yenta_socket */
while (bus->parent) {
if ((child->busn_res.end > bus->busn_res.end) ||
(child->number > bus->busn_res.end) ||
(child->number < bus->number) ||
(child->busn_res.end < bus->number)) {
dev_info(&child->dev, "%pR %s "
"hidden behind%s bridge %s %pR\n",
&child->busn_res,
(bus->number > child->busn_res.end &&
bus->busn_res.end < child->number) ?
"wholly" : "partially",
bus->self->transparent ? " transparent" : "",
dev_name(&bus->dev),
&bus->busn_res);
}
bus = bus->parent;
}
out:
pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
return max;
}
/*
* Read interrupt line and base address registers.
* The architecture-dependent code can tweak these, of course.
*/
static void pci_read_irq(struct pci_dev *dev)
{
unsigned char irq;
pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
dev->pin = irq;
if (irq)
pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
dev->irq = irq;
}
void set_pcie_port_type(struct pci_dev *pdev)
{
int pos;
u16 reg16;
pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
if (!pos)
return;
pdev->is_pcie = 1;
pdev->pcie_cap = pos;
pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, &reg16);
pdev->pcie_flags_reg = reg16;
pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, &reg16);
pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
}
void set_pcie_hotplug_bridge(struct pci_dev *pdev)
{
u32 reg32;
pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &reg32);
if (reg32 & PCI_EXP_SLTCAP_HPC)
pdev->is_hotplug_bridge = 1;
}
#define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
/**
* pci_setup_device - fill in class and map information of a device
* @dev: the device structure to fill
*
* Initialize the device structure with information about the device's
* vendor,class,memory and IO-space addresses,IRQ lines etc.
* Called at initialisation of the PCI subsystem and by CardBus services.
* Returns 0 on success and negative if unknown type of device (not normal,
* bridge or CardBus).
*/
int pci_setup_device(struct pci_dev *dev)
{
u32 class;
u8 hdr_type;
struct pci_slot *slot;
int pos = 0;
struct pci_bus_region region;
struct resource *res;
if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
return -EIO;
dev->sysdata = dev->bus->sysdata;
dev->dev.parent = dev->bus->bridge;
dev->dev.bus = &pci_bus_type;
dev->dev.type = &pci_dev_type;
dev->hdr_type = hdr_type & 0x7f;
dev->multifunction = !!(hdr_type & 0x80);
dev->error_state = pci_channel_io_normal;
set_pcie_port_type(dev);
list_for_each_entry(slot, &dev->bus->slots, list)
if (PCI_SLOT(dev->devfn) == slot->number)
dev->slot = slot;
/* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
set this higher, assuming the system even supports it. */
dev->dma_mask = 0xffffffff;
dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
dev->bus->number, PCI_SLOT(dev->devfn),
PCI_FUNC(dev->devfn));
pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
dev->revision = class & 0xff;
dev->class = class >> 8; /* upper 3 bytes */
dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %02x class %#08x\n",
dev->vendor, dev->device, dev->hdr_type, dev->class);
/* need to have dev->class ready */
dev->cfg_size = pci_cfg_space_size(dev);
/* "Unknown power state" */
dev->current_state = PCI_UNKNOWN;
/* Early fixups, before probing the BARs */
pci_fixup_device(pci_fixup_early, dev);
/* device class may be changed after fixup */
class = dev->class >> 8;
switch (dev->hdr_type) { /* header type */
case PCI_HEADER_TYPE_NORMAL: /* standard header */
if (class == PCI_CLASS_BRIDGE_PCI)
goto bad;
pci_read_irq(dev);
pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
/*
* Do the ugly legacy mode stuff here rather than broken chip
* quirk code. Legacy mode ATA controllers have fixed
* addresses. These are not always echoed in BAR0-3, and
* BAR0-3 in a few cases contain junk!
*/
if (class == PCI_CLASS_STORAGE_IDE) {
u8 progif;
pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
if ((progif & 1) == 0) {
region.start = 0x1F0;
region.end = 0x1F7;
res = &dev->resource[0];
res->flags = LEGACY_IO_RESOURCE;
pcibios_bus_to_resource(dev, res, &region);
region.start = 0x3F6;
region.end = 0x3F6;
res = &dev->resource[1];
res->flags = LEGACY_IO_RESOURCE;
pcibios_bus_to_resource(dev, res, &region);
}
if ((progif & 4) == 0) {
region.start = 0x170;
region.end = 0x177;
res = &dev->resource[2];
res->flags = LEGACY_IO_RESOURCE;
pcibios_bus_to_resource(dev, res, &region);
region.start = 0x376;
region.end = 0x376;
res = &dev->resource[3];
res->flags = LEGACY_IO_RESOURCE;
pcibios_bus_to_resource(dev, res, &region);
}
}
break;
case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
if (class != PCI_CLASS_BRIDGE_PCI)
goto bad;
/* The PCI-to-PCI bridge spec requires that subtractive
decoding (i.e. transparent) bridge must have programming
interface code of 0x01. */
pci_read_irq(dev);
dev->transparent = ((dev->class & 0xff) == 1);
pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
set_pcie_hotplug_bridge(dev);
pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
if (pos) {
pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
}
break;
case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
if (class != PCI_CLASS_BRIDGE_CARDBUS)
goto bad;
pci_read_irq(dev);
pci_read_bases(dev, 1, 0);
pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
break;
default: /* unknown header */
dev_err(&dev->dev, "unknown header type %02x, "
"ignoring device\n", dev->hdr_type);
return -EIO;
bad:
dev_err(&dev->dev, "ignoring class %#08x (doesn't match header "
"type %02x)\n", dev->class, dev->hdr_type);
dev->class = PCI_CLASS_NOT_DEFINED;
}
/* We found a fine healthy device, go go go... */
return 0;
}
static void pci_release_capabilities(struct pci_dev *dev)
{
pci_vpd_release(dev);
pci_iov_release(dev);
pci_free_cap_save_buffers(dev);
}
/**
* pci_release_dev - free a pci device structure when all users of it are finished.
* @dev: device that's been disconnected
*
* Will be called only by the device core when all users of this pci device are
* done.
*/
static void pci_release_dev(struct device *dev)
{
struct pci_dev *pci_dev;
pci_dev = to_pci_dev(dev);
pci_release_capabilities(pci_dev);
pci_release_of_node(pci_dev);
kfree(pci_dev);
}
/**
* pci_cfg_space_size - get the configuration space size of the PCI device.
* @dev: PCI device
*
* Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
* have 4096 bytes. Even if the device is capable, that doesn't mean we can
* access it. Maybe we don't have a way to generate extended config space
* accesses, or the device is behind a reverse Express bridge. So we try
* reading the dword at 0x100 which must either be 0 or a valid extended
* capability header.
*/
int pci_cfg_space_size_ext(struct pci_dev *dev)
{
u32 status;
int pos = PCI_CFG_SPACE_SIZE;
if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
goto fail;
if (status == 0xffffffff)
goto fail;
return PCI_CFG_SPACE_EXP_SIZE;
fail:
return PCI_CFG_SPACE_SIZE;
}
int pci_cfg_space_size(struct pci_dev *dev)
{
int pos;
u32 status;
u16 class;
class = dev->class >> 8;
if (class == PCI_CLASS_BRIDGE_HOST)
return pci_cfg_space_size_ext(dev);
if (!pci_is_pcie(dev)) {
pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
if (!pos)
goto fail;
pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
goto fail;
}
return pci_cfg_space_size_ext(dev);
fail:
return PCI_CFG_SPACE_SIZE;
}
static void pci_release_bus_bridge_dev(struct device *dev)
{
struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
if (bridge->release_fn)
bridge->release_fn(bridge);
pci_free_resource_list(&bridge->windows);
kfree(bridge);
}
struct pci_dev *alloc_pci_dev(void)
{
struct pci_dev *dev;
dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
if (!dev)
return NULL;
INIT_LIST_HEAD(&dev->bus_list);
return dev;
}
EXPORT_SYMBOL(alloc_pci_dev);
bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
int crs_timeout)
{
int delay = 1;
if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
return false;
/* some broken boards return 0 or ~0 if a slot is empty: */
if (*l == 0xffffffff || *l == 0x00000000 ||
*l == 0x0000ffff || *l == 0xffff0000)
return false;
/* Configuration request Retry Status */
while (*l == 0xffff0001) {
if (!crs_timeout)
return false;
msleep(delay);
delay *= 2;
if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
return false;
/* Card hasn't responded in 60 seconds? Must be stuck. */
if (delay > crs_timeout) {
printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not "
"responding\n", pci_domain_nr(bus),
bus->number, PCI_SLOT(devfn),
PCI_FUNC(devfn));
return false;
}
}
return true;
}
EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
/*
* Read the config data for a PCI device, sanity-check it
* and fill in the dev structure...
*/
static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
{
struct pci_dev *dev;
u32 l;
if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
return NULL;
dev = alloc_pci_dev();
if (!dev)
return NULL;
dev->bus = bus;
dev->devfn = devfn;
dev->vendor = l & 0xffff;
dev->device = (l >> 16) & 0xffff;
pci_set_of_node(dev);
if (pci_setup_device(dev)) {
kfree(dev);
return NULL;
}
return dev;
}
static void pci_init_capabilities(struct pci_dev *dev)
{
/* MSI/MSI-X list */
pci_msi_init_pci_dev(dev);
/* Buffers for saving PCIe and PCI-X capabilities */
pci_allocate_cap_save_buffers(dev);
/* Power Management */
pci_pm_init(dev);
/* Vital Product Data */
pci_vpd_pci22_init(dev);
/* Alternative Routing-ID Forwarding */
pci_enable_ari(dev);
/* Single Root I/O Virtualization */
pci_iov_init(dev);
/* Enable ACS P2P upstream forwarding */
pci_enable_acs(dev);
}
void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
{
device_initialize(&dev->dev);
dev->dev.release = pci_release_dev;
pci_dev_get(dev);
dev->dev.dma_mask = &dev->dma_mask;
dev->dev.dma_parms = &dev->dma_parms;
dev->dev.coherent_dma_mask = 0xffffffffull;
pci_set_dma_max_seg_size(dev, 65536);
pci_set_dma_seg_boundary(dev, 0xffffffff);
/* Fix up broken headers */
pci_fixup_device(pci_fixup_header, dev);
/* moved out from quirk header fixup code */
pci_reassigndev_resource_alignment(dev);
/* Clear the state_saved flag. */
dev->state_saved = false;
/* Initialize various capabilities */
pci_init_capabilities(dev);
/*
* Add the device to our list of discovered devices
* and the bus list for fixup functions, etc.
*/
down_write(&pci_bus_sem);
list_add_tail(&dev->bus_list, &bus->devices);
up_write(&pci_bus_sem);
}
struct pci_dev *__ref pci_scan_single_device(struct pci_bus *bus, int devfn)
{
struct pci_dev *dev;
dev = pci_get_slot(bus, devfn);
if (dev) {
pci_dev_put(dev);
return dev;
}
dev = pci_scan_device(bus, devfn);
if (!dev)
return NULL;
pci_device_add(dev, bus);
return dev;
}
EXPORT_SYMBOL(pci_scan_single_device);
static unsigned next_ari_fn(struct pci_dev *dev, unsigned fn)
{
u16 cap;
unsigned pos, next_fn;
if (!dev)
return 0;
pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
if (!pos)
return 0;
pci_read_config_word(dev, pos + 4, &cap);
next_fn = cap >> 8;
if (next_fn <= fn)
return 0;
return next_fn;
}
static unsigned next_trad_fn(struct pci_dev *dev, unsigned fn)
{
return (fn + 1) % 8;
}
static unsigned no_next_fn(struct pci_dev *dev, unsigned fn)
{
return 0;
}
static int only_one_child(struct pci_bus *bus)
{
struct pci_dev *parent = bus->self;
if (!parent || !pci_is_pcie(parent))
return 0;
if (pci_pcie_type(parent) == PCI_EXP_TYPE_ROOT_PORT)
return 1;
if (pci_pcie_type(parent) == PCI_EXP_TYPE_DOWNSTREAM &&
!pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
return 1;
return 0;
}
/**
* pci_scan_slot - scan a PCI slot on a bus for devices.
* @bus: PCI bus to scan
* @devfn: slot number to scan (must have zero function.)
*
* Scan a PCI slot on the specified PCI bus for devices, adding
* discovered devices to the @bus->devices list. New devices
* will not have is_added set.
*
* Returns the number of new devices found.
*/
int pci_scan_slot(struct pci_bus *bus, int devfn)
{
unsigned fn, nr = 0;
struct pci_dev *dev;
unsigned (*next_fn)(struct pci_dev *, unsigned) = no_next_fn;
if (only_one_child(bus) && (devfn > 0))
return 0; /* Already scanned the entire slot */
dev = pci_scan_single_device(bus, devfn);
if (!dev)
return 0;
if (!dev->is_added)
nr++;
if (pci_ari_enabled(bus))
next_fn = next_ari_fn;
else if (dev->multifunction)
next_fn = next_trad_fn;
for (fn = next_fn(dev, 0); fn > 0; fn = next_fn(dev, fn)) {
dev = pci_scan_single_device(bus, devfn + fn);
if (dev) {
if (!dev->is_added)
nr++;
dev->multifunction = 1;
}
}
/* only one slot has pcie device */
if (bus->self && nr)
pcie_aspm_init_link_state(bus->self);
return nr;
}
static int pcie_find_smpss(struct pci_dev *dev, void *data)
{
u8 *smpss = data;
if (!pci_is_pcie(dev))
return 0;
/* For PCIE hotplug enabled slots not connected directly to a
* PCI-E root port, there can be problems when hotplugging
* devices. This is due to the possibility of hotplugging a
* device into the fabric with a smaller MPS that the devices
* currently running have configured. Modifying the MPS on the
* running devices could cause a fatal bus error due to an
* incoming frame being larger than the newly configured MPS.
* To work around this, the MPS for the entire fabric must be
* set to the minimum size. Any devices hotplugged into this
* fabric will have the minimum MPS set. If the PCI hotplug
* slot is directly connected to the root port and there are not
* other devices on the fabric (which seems to be the most
* common case), then this is not an issue and MPS discovery
* will occur as normal.
*/
if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) ||
(dev->bus->self &&
pci_pcie_type(dev->bus->self) != PCI_EXP_TYPE_ROOT_PORT)))
*smpss = 0;
if (*smpss > dev->pcie_mpss)
*smpss = dev->pcie_mpss;
return 0;
}
static void pcie_write_mps(struct pci_dev *dev, int mps)
{
int rc;
if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
mps = 128 << dev->pcie_mpss;
if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
dev->bus->self)
/* For "Performance", the assumption is made that
* downstream communication will never be larger than
* the MRRS. So, the MPS only needs to be configured
* for the upstream communication. This being the case,
* walk from the top down and set the MPS of the child
* to that of the parent bus.
*
* Configure the device MPS with the smaller of the
* device MPSS or the bridge MPS (which is assumed to be
* properly configured at this point to the largest
* allowable MPS based on its parent bus).
*/
mps = min(mps, pcie_get_mps(dev->bus->self));
}
rc = pcie_set_mps(dev, mps);
if (rc)
dev_err(&dev->dev, "Failed attempting to set the MPS\n");
}
static void pcie_write_mrrs(struct pci_dev *dev)
{
int rc, mrrs;
/* In the "safe" case, do not configure the MRRS. There appear to be
* issues with setting MRRS to 0 on a number of devices.
*/
if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
return;
/* For Max performance, the MRRS must be set to the largest supported
* value. However, it cannot be configured larger than the MPS the
* device or the bus can support. This should already be properly
* configured by a prior call to pcie_write_mps.
*/
mrrs = pcie_get_mps(dev);
/* MRRS is a R/W register. Invalid values can be written, but a
* subsequent read will verify if the value is acceptable or not.
* If the MRRS value provided is not acceptable (e.g., too large),
* shrink the value until it is acceptable to the HW.
*/
while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
rc = pcie_set_readrq(dev, mrrs);
if (!rc)
break;
dev_warn(&dev->dev, "Failed attempting to set the MRRS\n");
mrrs /= 2;
}
if (mrrs < 128)
dev_err(&dev->dev, "MRRS was unable to be configured with a "
"safe value. If problems are experienced, try running "
"with pci=pcie_bus_safe.\n");
}
static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
{
int mps, orig_mps;
if (!pci_is_pcie(dev))
return 0;
mps = 128 << *(u8 *)data;
orig_mps = pcie_get_mps(dev);
pcie_write_mps(dev, mps);
pcie_write_mrrs(dev);
dev_info(&dev->dev, "PCI-E Max Payload Size set to %4d/%4d (was %4d), "
"Max Read Rq %4d\n", pcie_get_mps(dev), 128 << dev->pcie_mpss,
orig_mps, pcie_get_readrq(dev));
return 0;
}
/* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down,
* parents then children fashion. If this changes, then this code will not
* work as designed.
*/
void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss)
{
u8 smpss;
if (!pci_is_pcie(bus->self))
return;
if (pcie_bus_config == PCIE_BUS_TUNE_OFF)
return;
/* FIXME - Peer to peer DMA is possible, though the endpoint would need
* to be aware to the MPS of the destination. To work around this,
* simply force the MPS of the entire system to the smallest possible.
*/
if (pcie_bus_config == PCIE_BUS_PEER2PEER)
smpss = 0;
if (pcie_bus_config == PCIE_BUS_SAFE) {
smpss = mpss;
pcie_find_smpss(bus->self, &smpss);
pci_walk_bus(bus, pcie_find_smpss, &smpss);
}
pcie_bus_configure_set(bus->self, &smpss);
pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
}
EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
unsigned int pci_scan_child_bus(struct pci_bus *bus)
{
unsigned int devfn, pass, max = bus->busn_res.start;
struct pci_dev *dev;
dev_dbg(&bus->dev, "scanning bus\n");
/* Go find them, Rover! */
for (devfn = 0; devfn < 0x100; devfn += 8)
pci_scan_slot(bus, devfn);
/* Reserve buses for SR-IOV capability. */
max += pci_iov_bus_range(bus);
/*
* After performing arch-dependent fixup of the bus, look behind
* all PCI-to-PCI bridges on this bus.
*/
if (!bus->is_added) {
dev_dbg(&bus->dev, "fixups for bus\n");
pcibios_fixup_bus(bus);
if (pci_is_root_bus(bus))
bus->is_added = 1;
}
for (pass=0; pass < 2; pass++)
list_for_each_entry(dev, &bus->devices, bus_list) {
if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
max = pci_scan_bridge(bus, dev, max, pass);
}
/*
* We've scanned the bus and so we know all about what's on
* the other side of any bridges that may be on this bus plus
* any devices.
*
* Return how far we've got finding sub-buses.
*/
dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
return max;
}
/**
* pcibios_root_bridge_prepare - Platform-specific host bridge setup.
* @bridge: Host bridge to set up.
*
* Default empty implementation. Replace with an architecture-specific setup
* routine, if necessary.
*/
int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
{
return 0;
}
struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
struct pci_ops *ops, void *sysdata, struct list_head *resources)
{
int error;
struct pci_host_bridge *bridge;
struct pci_bus *b, *b2;
struct pci_host_bridge_window *window, *n;
struct resource *res;
resource_size_t offset;
char bus_addr[64];
char *fmt;
b = pci_alloc_bus();
if (!b)
return NULL;
b->sysdata = sysdata;
b->ops = ops;
b2 = pci_find_bus(pci_domain_nr(b), bus);
if (b2) {
/* If we already got to this bus through a different bridge, ignore it */
dev_dbg(&b2->dev, "bus already known\n");
goto err_out;
}
bridge = pci_alloc_host_bridge(b);
if (!bridge)
goto err_out;
bridge->dev.parent = parent;
bridge->dev.release = pci_release_bus_bridge_dev;
dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
error = pcibios_root_bridge_prepare(bridge);
if (error)
goto bridge_dev_reg_err;
error = device_register(&bridge->dev);
if (error)
goto bridge_dev_reg_err;
b->bridge = get_device(&bridge->dev);
device_enable_async_suspend(b->bridge);
pci_set_bus_of_node(b);
if (!parent)
set_dev_node(b->bridge, pcibus_to_node(b));
b->dev.class = &pcibus_class;
b->dev.parent = b->bridge;
dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
error = device_register(&b->dev);
if (error)
goto class_dev_reg_err;
/* Create legacy_io and legacy_mem files for this bus */
pci_create_legacy_files(b);
b->number = b->busn_res.start = bus;
if (parent)
dev_info(parent, "PCI host bridge to bus %s\n", dev_name(&b->dev));
else
printk(KERN_INFO "PCI host bridge to bus %s\n", dev_name(&b->dev));
/* Add initial resources to the bus */
list_for_each_entry_safe(window, n, resources, list) {
list_move_tail(&window->list, &bridge->windows);
res = window->res;
offset = window->offset;
if (res->flags & IORESOURCE_BUS)
pci_bus_insert_busn_res(b, bus, res->end);
else
pci_bus_add_resource(b, res, 0);
if (offset) {
if (resource_type(res) == IORESOURCE_IO)
fmt = " (bus address [%#06llx-%#06llx])";
else
fmt = " (bus address [%#010llx-%#010llx])";
snprintf(bus_addr, sizeof(bus_addr), fmt,
(unsigned long long) (res->start - offset),
(unsigned long long) (res->end - offset));
} else
bus_addr[0] = '\0';
dev_info(&b->dev, "root bus resource %pR%s\n", res, bus_addr);
}
down_write(&pci_bus_sem);
list_add_tail(&b->node, &pci_root_buses);
up_write(&pci_bus_sem);
return b;
class_dev_reg_err:
put_device(&bridge->dev);
device_unregister(&bridge->dev);
bridge_dev_reg_err:
kfree(bridge);
err_out:
kfree(b);
return NULL;
}
int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
{
struct resource *res = &b->busn_res;
struct resource *parent_res, *conflict;
res->start = bus;
res->end = bus_max;
res->flags = IORESOURCE_BUS;
if (!pci_is_root_bus(b))
parent_res = &b->parent->busn_res;
else {
parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
res->flags |= IORESOURCE_PCI_FIXED;
}
conflict = insert_resource_conflict(parent_res, res);
if (conflict)
dev_printk(KERN_DEBUG, &b->dev,
"busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
res, pci_is_root_bus(b) ? "domain " : "",
parent_res, conflict->name, conflict);
return conflict == NULL;
}
int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
{
struct resource *res = &b->busn_res;
struct resource old_res = *res;
resource_size_t size;
int ret;
if (res->start > bus_max)
return -EINVAL;
size = bus_max - res->start + 1;
ret = adjust_resource(res, res->start, size);
dev_printk(KERN_DEBUG, &b->dev,
"busn_res: %pR end %s updated to %02x\n",
&old_res, ret ? "can not be" : "is", bus_max);
if (!ret && !res->parent)
pci_bus_insert_busn_res(b, res->start, res->end);
return ret;
}
void pci_bus_release_busn_res(struct pci_bus *b)
{
struct resource *res = &b->busn_res;
int ret;
if (!res->flags || !res->parent)
return;
ret = release_resource(res);
dev_printk(KERN_DEBUG, &b->dev,
"busn_res: %pR %s released\n",
res, ret ? "can not be" : "is");
}
struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
struct pci_ops *ops, void *sysdata, struct list_head *resources)
{
struct pci_host_bridge_window *window;
bool found = false;
struct pci_bus *b;
int max;
list_for_each_entry(window, resources, list)
if (window->res->flags & IORESOURCE_BUS) {
found = true;
break;
}
b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
if (!b)
return NULL;
if (!found) {
dev_info(&b->dev,
"No busn resource found for root bus, will use [bus %02x-ff]\n",
bus);
pci_bus_insert_busn_res(b, bus, 255);
}
max = pci_scan_child_bus(b);
if (!found)
pci_bus_update_busn_res_end(b, max);
pci_bus_add_devices(b);
return b;
}
EXPORT_SYMBOL(pci_scan_root_bus);
/* Deprecated; use pci_scan_root_bus() instead */
struct pci_bus *pci_scan_bus_parented(struct device *parent,
int bus, struct pci_ops *ops, void *sysdata)
{
LIST_HEAD(resources);
struct pci_bus *b;
pci_add_resource(&resources, &ioport_resource);
pci_add_resource(&resources, &iomem_resource);
pci_add_resource(&resources, &busn_resource);
b = pci_create_root_bus(parent, bus, ops, sysdata, &resources);
if (b)
pci_scan_child_bus(b);
else
pci_free_resource_list(&resources);
return b;
}
EXPORT_SYMBOL(pci_scan_bus_parented);
struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
void *sysdata)
{
LIST_HEAD(resources);
struct pci_bus *b;
pci_add_resource(&resources, &ioport_resource);
pci_add_resource(&resources, &iomem_resource);
pci_add_resource(&resources, &busn_resource);
b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
if (b) {
pci_scan_child_bus(b);
pci_bus_add_devices(b);
} else {
pci_free_resource_list(&resources);
}
return b;
}
EXPORT_SYMBOL(pci_scan_bus);
/**
* pci_rescan_bus_bridge_resize - scan a PCI bus for devices.
* @bridge: PCI bridge for the bus to scan
*
* Scan a PCI bus and child buses for new devices, add them,
* and enable them, resizing bridge mmio/io resource if necessary
* and possible. The caller must ensure the child devices are already
* removed for resizing to occur.
*
* Returns the max number of subordinate bus discovered.
*/
unsigned int __ref pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
{
unsigned int max;
struct pci_bus *bus = bridge->subordinate;
max = pci_scan_child_bus(bus);
pci_assign_unassigned_bridge_resources(bridge);
pci_bus_add_devices(bus);
return max;
}
/**
* pci_rescan_bus - scan a PCI bus for devices.
* @bus: PCI bus to scan
*
* Scan a PCI bus and child buses for new devices, adds them,
* and enables them.
*
* Returns the max number of subordinate bus discovered.
*/
unsigned int __ref pci_rescan_bus(struct pci_bus *bus)
{
unsigned int max;
max = pci_scan_child_bus(bus);
pci_assign_unassigned_bus_resources(bus);
pci_enable_bridges(bus);
pci_bus_add_devices(bus);
return max;
}
EXPORT_SYMBOL_GPL(pci_rescan_bus);
EXPORT_SYMBOL(pci_add_new_bus);
EXPORT_SYMBOL(pci_scan_slot);
EXPORT_SYMBOL(pci_scan_bridge);
EXPORT_SYMBOL_GPL(pci_scan_child_bus);
static int __init pci_sort_bf_cmp(const struct device *d_a, const struct device *d_b)
{
const struct pci_dev *a = to_pci_dev(d_a);
const struct pci_dev *b = to_pci_dev(d_b);
if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
if (a->bus->number < b->bus->number) return -1;
else if (a->bus->number > b->bus->number) return 1;
if (a->devfn < b->devfn) return -1;
else if (a->devfn > b->devfn) return 1;
return 0;
}
void __init pci_sort_breadthfirst(void)
{
bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);
}