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linux-sg2042/drivers/pci/probe.c

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/*
* 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
static 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_groups = pcibus_groups,
};
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;
}
#define PCI_COMMAND_DECODE_ENABLE (PCI_COMMAND_MEMORY | PCI_COMMAND_IO)
/**
* 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;
u64 l64, sz64, mask64;
u16 orig_cmd;
struct pci_bus_region region, inverted_region;
bool bar_too_big = false, bar_too_high = false, bar_invalid = 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);
if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) {
pci_write_config_word(dev, PCI_COMMAND,
orig_cmd & ~PCI_COMMAND_DECODE_ENABLE);
}
}
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) {
l64 = l;
sz64 = sz;
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(dma_addr_t) < 8 || sizeof(resource_size_t) < 8) &&
sz64 > 0x100000000ULL) {
res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
res->start = 0;
res->end = 0;
bar_too_big = true;
goto out;
}
if ((sizeof(dma_addr_t) < 8) && l) {
/* Above 32-bit boundary; try to reallocate */
res->flags |= IORESOURCE_UNSET;
res->start = 0;
res->end = sz64;
bar_too_high = true;
goto out;
} else {
region.start = l64;
region.end = l64 + sz64;
}
} else {
sz = pci_size(l, sz, mask);
if (!sz)
goto fail;
region.start = l;
region.end = l + sz;
}
pcibios_bus_to_resource(dev->bus, res, &region);
pcibios_resource_to_bus(dev->bus, &inverted_region, res);
/*
* If "A" is a BAR value (a bus address), "bus_to_resource(A)" is
* the corresponding resource address (the physical address used by
* the CPU. Converting that resource address back to a bus address
* should yield the original BAR value:
*
* resource_to_bus(bus_to_resource(A)) == A
*
* If it doesn't, CPU accesses to "bus_to_resource(A)" will not
* be claimed by the device.
*/
if (inverted_region.start != region.start) {
res->flags |= IORESOURCE_UNSET;
res->start = 0;
res->end = region.end - region.start;
bar_invalid = true;
}
goto out;
fail:
res->flags = 0;
out:
if (!dev->mmio_always_on &&
(orig_cmd & PCI_COMMAND_DECODE_ENABLE))
pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
if (bar_too_big)
dev_err(&dev->dev, "reg 0x%x: can't handle BAR larger than 4GB (size %#010llx)\n",
pos, (unsigned long long) sz64);
if (bar_too_high)
dev_info(&dev->dev, "reg 0x%x: can't handle BAR above 4G (bus address %#010llx)\n",
pos, (unsigned long long) l64);
if (bar_invalid)
dev_info(&dev->dev, "reg 0x%x: initial BAR value %#010llx invalid\n",
pos, (unsigned long long) region.start);
if (res->flags)
dev_printk(KERN_DEBUG, &dev->dev, "reg 0x%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->bus, 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->bus, 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->bus, 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 && res->flags) {
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)
return NULL;
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 void pci_release_host_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);
}
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)
return NULL;
INIT_LIST_HEAD(&bridge->windows);
bridge->bus = b;
return bridge;
}
static const 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 */
};
const 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;
}
if (pci_is_pcie(bridge)) {
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;
int ret;
/*
* 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->msi = parent->msi;
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.
*/
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) {
child->dev.parent = parent->bridge;
goto add_dev;
}
child->self = bridge;
child->bridge = get_device(&bridge->dev);
child->dev.parent = child->bridge;
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;
add_dev:
ret = device_register(&child->dev);
WARN_ON(ret < 0);
pcibios_add_bus(child);
/* Create legacy_io and legacy_mem files for this bus */
pci_create_legacy_files(child);
return child;
}
struct pci_bus *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;
}
EXPORT_SYMBOL(pci_add_new_bus);
/*
* 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 || subordinate > bus->busn_res.end)) {
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;
/*
* The bus might already exist for two reasons: Either we are
* rescanning the bus or the bus is reachable through more than
* one bridge. The second case can happen with the i450NX
* chipset.
*/
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 > subordinate)
dev_warn(&dev->dev, "bridge has subordinate %02x but max busn %02x\n",
subordinate, cmax);
/* subordinate should equal child->busn_res.end */
if (subordinate > max)
max = subordinate;
} 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 || is_cardbus)
/* 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;
}
if (max >= bus->busn_res.end) {
dev_warn(&dev->dev, "can't allocate child bus %02x from %pR\n",
max, &bus->busn_res);
goto out;
}
/* Clear errors */
pci_write_config_word(dev, PCI_STATUS, 0xffff);
/* The bus will already exist if we are rescanning */
child = pci_find_bus(pci_domain_nr(bus), max+1);
if (!child) {
child = pci_add_new_bus(bus, dev, max+1);
if (!child)
goto out;
pci_bus_insert_busn_res(child, max+1,
bus->busn_res.end);
}
max++;
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;
max = pci_scan_child_bus(child);
} 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;
}
/*
* Set the subordinate bus number to its real value.
*/
if (max > bus->busn_res.end) {
dev_warn(&dev->dev, "max busn %02x is outside %pR\n",
max, &bus->busn_res);
max = bus->busn_res.end;
}
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;
}
EXPORT_SYMBOL(pci_scan_bridge);
/*
* 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->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;
}
/**
* pci_ext_cfg_is_aliased - is ext config space just an alias of std config?
* @dev: PCI device
*
* PCI Express to PCI/PCI-X Bridge Specification, rev 1.0, 4.1.4 says that
* when forwarding a type1 configuration request the bridge must check that
* the extended register address field is zero. The bridge is not permitted
* to forward the transactions and must handle it as an Unsupported Request.
* Some bridges do not follow this rule and simply drop the extended register
* bits, resulting in the standard config space being aliased, every 256
* bytes across the entire configuration space. Test for this condition by
* comparing the first dword of each potential alias to the vendor/device ID.
* Known offenders:
* ASM1083/1085 PCIe-to-PCI Reversible Bridge (1b21:1080, rev 01 & 03)
* AMD/ATI SBx00 PCI to PCI Bridge (1002:4384, rev 40)
*/
static bool pci_ext_cfg_is_aliased(struct pci_dev *dev)
{
#ifdef CONFIG_PCI_QUIRKS
int pos;
u32 header, tmp;
pci_read_config_dword(dev, PCI_VENDOR_ID, &header);
for (pos = PCI_CFG_SPACE_SIZE;
pos < PCI_CFG_SPACE_EXP_SIZE; pos += PCI_CFG_SPACE_SIZE) {
if (pci_read_config_dword(dev, pos, &tmp) != PCIBIOS_SUCCESSFUL
|| header != tmp)
return false;
}
return true;
#else
return false;
#endif
}
/**
* 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.
*/
static 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 || pci_ext_cfg_is_aliased(dev))
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;
}
#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->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->bus, res, &region);
dev_info(&dev->dev, "legacy IDE quirk: reg 0x10: %pR\n",
res);
region.start = 0x3F6;
region.end = 0x3F6;
res = &dev->resource[1];
res->flags = LEGACY_IO_RESOURCE;
pcibios_bus_to_resource(dev->bus, res, &region);
dev_info(&dev->dev, "legacy IDE quirk: reg 0x14: %pR\n",
res);
}
if ((progif & 4) == 0) {
region.start = 0x170;
region.end = 0x177;
res = &dev->resource[2];
res->flags = LEGACY_IO_RESOURCE;
pcibios_bus_to_resource(dev->bus, res, &region);
dev_info(&dev->dev, "legacy IDE quirk: reg 0x18: %pR\n",
res);
region.start = 0x376;
region.end = 0x376;
res = &dev->resource[3];
res->flags = LEGACY_IO_RESOURCE;
pcibios_bus_to_resource(dev->bus, res, &region);
dev_info(&dev->dev, "legacy IDE quirk: reg 0x1c: %pR\n",
res);
}
}
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);
pcibios_release_device(pci_dev);
pci_bus_put(pci_dev->bus);
kfree(pci_dev->driver_override);
kfree(pci_dev);
}
struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
{
struct pci_dev *dev;
dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
if (!dev)
return NULL;
INIT_LIST_HEAD(&dev->bus_list);
dev->dev.type = &pci_dev_type;
dev->bus = pci_bus_get(bus);
return dev;
}
EXPORT_SYMBOL(pci_alloc_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 = pci_alloc_dev(bus);
if (!dev)
return NULL;
dev->devfn = devfn;
dev->vendor = l & 0xffff;
dev->device = (l >> 16) & 0xffff;
pci_set_of_node(dev);
if (pci_setup_device(dev)) {
pci_bus_put(dev->bus);
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_configure_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)
{
int ret;
device_initialize(&dev->dev);
dev->dev.release = pci_release_dev;
set_dev_node(&dev->dev, pcibus_to_node(bus));
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);
ret = pcibios_add_device(dev);
WARN_ON(ret < 0);
/* Notifier could use PCI capabilities */
dev->match_driver = false;
ret = device_add(&dev->dev);
WARN_ON(ret < 0);
}
struct pci_dev *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_fn(struct pci_bus *bus, struct pci_dev *dev, unsigned fn)
{
int pos;
u16 cap = 0;
unsigned next_fn;
if (pci_ari_enabled(bus)) {
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 + PCI_ARI_CAP, &cap);
next_fn = PCI_ARI_CAP_NFN(cap);
if (next_fn <= fn)
return 0; /* protect against malformed list */
return next_fn;
}
/* dev may be NULL for non-contiguous multifunction devices */
if (!dev || dev->multifunction)
return (fn + 1) % 8;
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;
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++;
for (fn = next_fn(bus, dev, 0); fn > 0; fn = next_fn(bus, 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;
}
EXPORT_SYMBOL(pci_scan_slot);
static int pcie_find_smpss(struct pci_dev *dev, void *data)
{
u8 *smpss = data;
if (!pci_is_pcie(dev))
return 0;
/*
* We don't have a way to change MPS settings on devices that have
* drivers attached. A hot-added device might support only the minimum
* MPS setting (MPS=128). Therefore, if the fabric contains a bridge
* where devices may be hot-added, we limit the fabric MPS to 128 so
* hot-added devices will work correctly.
*
* However, if we hot-add a device to a slot directly below a Root
* Port, it's impossible for there to be other existing devices below
* the port. We don't limit the MPS in this case because we can
* reconfigure MPS on both the Root Port and the hot-added device,
* and there are no other devices involved.
*
* Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
*/
if (dev->is_hotplug_bridge &&
pci_pcie_type(dev) != 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 void pcie_bus_detect_mps(struct pci_dev *dev)
{
struct pci_dev *bridge = dev->bus->self;
int mps, p_mps;
if (!bridge)
return;
mps = pcie_get_mps(dev);
p_mps = pcie_get_mps(bridge);
if (mps != p_mps)
dev_warn(&dev->dev, "Max Payload Size %d, but upstream %s set to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
mps, pci_name(bridge), p_mps);
}
static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
{
int mps, orig_mps;
if (!pci_is_pcie(dev))
return 0;
if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
pcie_bus_detect_mps(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, "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 smpss = 0;
if (!bus->self)
return;
if (!pci_is_pcie(bus->self))
return;
/* FIXME - Peer to peer DMA is possible, though the endpoint would need
* to be aware of 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 = bus->self->pcie_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);
bus->is_added = 1;
}
for (pass = 0; pass < 2; pass++)
list_for_each_entry(dev, &bus->devices, bus_list) {
if (pci_is_bridge(dev))
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;
}
EXPORT_SYMBOL_GPL(pci_scan_child_bus);
/**
* 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;
}
void __weak pcibios_add_bus(struct pci_bus *bus)
{
}
void __weak pcibios_remove_bus(struct pci_bus *bus)
{
}
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;
b->number = b->busn_res.start = bus;
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_host_bridge_dev;
dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
error = pcibios_root_bridge_prepare(bridge);
if (error) {
kfree(bridge);
goto err_out;
}
error = device_register(&bridge->dev);
if (error) {
put_device(&bridge->dev);
goto err_out;
}
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;
pcibios_add_bus(b);
/* Create legacy_io and legacy_mem files for this bus */
pci_create_legacy_files(b);
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);
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 = request_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 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 pci_rescan_bus(struct pci_bus *bus)
{
unsigned int max;
max = pci_scan_child_bus(bus);
pci_assign_unassigned_bus_resources(bus);
pci_bus_add_devices(bus);
return max;
}
EXPORT_SYMBOL_GPL(pci_rescan_bus);
/*
* pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal
* routines should always be executed under this mutex.
*/
static DEFINE_MUTEX(pci_rescan_remove_lock);
void pci_lock_rescan_remove(void)
{
mutex_lock(&pci_rescan_remove_lock);
}
EXPORT_SYMBOL_GPL(pci_lock_rescan_remove);
void pci_unlock_rescan_remove(void)
{
mutex_unlock(&pci_rescan_remove_lock);
}
EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove);
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);
}
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