- 根目录:
- arch
- powerpc
- kernel
- pci_of_scan.c
/*
* Helper routines to scan the device tree for PCI devices and busses
*
* Migrated out of PowerPC architecture pci_64.c file by Grant Likely
* <grant.likely@secretlab.ca> so that these routines are available for
* 32 bit also.
*
* Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
* Rework, based on alpha PCI code.
* Copyright (c) 2009 Secret Lab Technologies Ltd.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*/
#include <linux/pci.h>
#include <linux/export.h>
#include <asm/pci-bridge.h>
#include <asm/prom.h>
/**
* get_int_prop - Decode a u32 from a device tree property
*/
static u32 get_int_prop(struct device_node *np, const char *name, u32 def)
{
const __be32 *prop;
int len;
prop = of_get_property(np, name, &len);
if (prop && len >= 4)
return of_read_number(prop, 1);
return def;
}
/**
* pci_parse_of_flags - Parse the flags cell of a device tree PCI address
* @addr0: value of 1st cell of a device tree PCI address.
* @bridge: Set this flag if the address is from a bridge 'ranges' property
*/
static unsigned int pci_parse_of_flags(u32 addr0, int bridge)
{
unsigned int flags = 0;
if (addr0 & 0x02000000) {
flags = IORESOURCE_MEM | PCI_BASE_ADDRESS_SPACE_MEMORY;
flags |= (addr0 >> 22) & PCI_BASE_ADDRESS_MEM_TYPE_64;
flags |= (addr0 >> 28) & PCI_BASE_ADDRESS_MEM_TYPE_1M;
if (addr0 & 0x40000000)
flags |= IORESOURCE_PREFETCH
| PCI_BASE_ADDRESS_MEM_PREFETCH;
/* Note: We don't know whether the ROM has been left enabled
* by the firmware or not. We mark it as disabled (ie, we do
* not set the IORESOURCE_ROM_ENABLE flag) for now rather than
* do a config space read, it will be force-enabled if needed
*/
if (!bridge && (addr0 & 0xff) == 0x30)
flags |= IORESOURCE_READONLY;
} else if (addr0 & 0x01000000)
flags = IORESOURCE_IO | PCI_BASE_ADDRESS_SPACE_IO;
if (flags)
flags |= IORESOURCE_SIZEALIGN;
return flags;
}
/**
* of_pci_parse_addrs - Parse PCI addresses assigned in the device tree node
* @node: device tree node for the PCI device
* @dev: pci_dev structure for the device
*
* This function parses the 'assigned-addresses' property of a PCI devices'
* device tree node and writes them into the associated pci_dev structure.
*/
static void of_pci_parse_addrs(struct device_node *node, struct pci_dev *dev)
{
u64 base, size;
unsigned int flags;
struct pci_bus_region region;
struct resource *res;
const __be32 *addrs;
u32 i;
int proplen;
addrs = of_get_property(node, "assigned-addresses", &proplen);
if (!addrs)
return;
pr_debug(" parse addresses (%d bytes) @ %p\n", proplen, addrs);
for (; proplen >= 20; proplen -= 20, addrs += 5) {
flags = pci_parse_of_flags(of_read_number(addrs, 1), 0);
if (!flags)
continue;
base = of_read_number(&addrs[1], 2);
size = of_read_number(&addrs[3], 2);
if (!size)
continue;
i = of_read_number(addrs, 1) & 0xff;
pr_debug(" base: %llx, size: %llx, i: %x\n",
(unsigned long long)base,
(unsigned long long)size, i);
if (PCI_BASE_ADDRESS_0 <= i && i <= PCI_BASE_ADDRESS_5) {
res = &dev->resource[(i - PCI_BASE_ADDRESS_0) >> 2];
} else if (i == dev->rom_base_reg) {
res = &dev->resource[PCI_ROM_RESOURCE];
flags |= IORESOURCE_READONLY | IORESOURCE_CACHEABLE;
} else {
printk(KERN_ERR "PCI: bad cfg reg num 0x%x\n", i);
continue;
}
res->flags = flags;
res->name = pci_name(dev);
region.start = base;
region.end = base + size - 1;
pcibios_bus_to_resource(dev->bus, res, ®ion);
}
}
/**
* of_create_pci_dev - Given a device tree node on a pci bus, create a pci_dev
* @node: device tree node pointer
* @bus: bus the device is sitting on
* @devfn: PCI function number, extracted from device tree by caller.
*/
struct pci_dev *of_create_pci_dev(struct device_node *node,
struct pci_bus *bus, int devfn)
{
struct pci_dev *dev;
const char *type;
struct pci_slot *slot;
dev = pci_alloc_dev(bus);
if (!dev)
return NULL;
type = of_get_property(node, "device_type", NULL);
if (type == NULL)
type = "";
pr_debug(" create device, devfn: %x, type: %s\n", devfn, type);
dev->dev.of_node = of_node_get(node);
dev->dev.parent = bus->bridge;
dev->dev.bus = &pci_bus_type;
dev->devfn = devfn;
dev->multifunction = 0; /* maybe a lie? */
dev->needs_freset = 0; /* pcie fundamental reset required */
set_pcie_port_type(dev);
list_for_each_entry(slot, &dev->bus->slots, list)
if (PCI_SLOT(dev->devfn) == slot->number)
dev->slot = slot;
dev->vendor = get_int_prop(node, "vendor-id", 0xffff);
dev->device = get_int_prop(node, "device-id", 0xffff);
dev->subsystem_vendor = get_int_prop(node, "subsystem-vendor-id", 0);
dev->subsystem_device = get_int_prop(node, "subsystem-id", 0);
dev->cfg_size = pci_cfg_space_size(dev);
dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(bus),
dev->bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn));
dev->class = get_int_prop(node, "class-code", 0);
dev->revision = get_int_prop(node, "revision-id", 0);
pr_debug(" class: 0x%x\n", dev->class);
pr_debug(" revision: 0x%x\n", dev->revision);
dev->current_state = PCI_UNKNOWN; /* unknown power state */
dev->error_state = pci_channel_io_normal;
dev->dma_mask = 0xffffffff;
/* Early fixups, before probing the BARs */
pci_fixup_device(pci_fixup_early, dev);
if (!strcmp(type, "pci") || !strcmp(type, "pciex")) {
/* a PCI-PCI bridge */
dev->hdr_type = PCI_HEADER_TYPE_BRIDGE;
dev->rom_base_reg = PCI_ROM_ADDRESS1;
set_pcie_hotplug_bridge(dev);
} else if (!strcmp(type, "cardbus")) {
dev->hdr_type = PCI_HEADER_TYPE_CARDBUS;
} else {
dev->hdr_type = PCI_HEADER_TYPE_NORMAL;
dev->rom_base_reg = PCI_ROM_ADDRESS;
/* Maybe do a default OF mapping here */
dev->irq = NO_IRQ;
}
of_pci_parse_addrs(node, dev);
pr_debug(" adding to system ...\n");
pci_device_add(dev, bus);
return dev;
}
EXPORT_SYMBOL(of_create_pci_dev);
/**
* of_scan_pci_bridge - Set up a PCI bridge and scan for child nodes
* @dev: pci_dev structure for the bridge
*
* of_scan_bus() calls this routine for each PCI bridge that it finds, and
* this routine in turn call of_scan_bus() recusively to scan for more child
* devices.
*/
void of_scan_pci_bridge(struct pci_dev *dev)
{
struct device_node *node = dev->dev.of_node;
struct pci_bus *bus;
const __be32 *busrange, *ranges;
int len, i, mode;
struct pci_bus_region region;
struct resource *res;
unsigned int flags;
u64 size;
pr_debug("of_scan_pci_bridge(%s)\n", node->full_name);
/* parse bus-range property */
busrange = of_get_property(node, "bus-range", &len);
if (busrange == NULL || len != 8) {
printk(KERN_DEBUG "Can't get bus-range for PCI-PCI bridge %s\n",
node->full_name);
return;
}
ranges = of_get_property(node, "ranges", &len);
if (ranges == NULL) {
printk(KERN_DEBUG "Can't get ranges for PCI-PCI bridge %s\n",
node->full_name);
return;
}
bus = pci_find_bus(pci_domain_nr(dev->bus),
of_read_number(busrange, 1));
if (!bus) {
bus = pci_add_new_bus(dev->bus, dev,
of_read_number(busrange, 1));
if (!bus) {
printk(KERN_ERR "Failed to create pci bus for %s\n",
node->full_name);
return;
}
}
bus->primary = dev->bus->number;
pci_bus_insert_busn_res(bus, of_read_number(busrange, 1),
of_read_number(busrange+1, 1));
bus->bridge_ctl = 0;
/* parse ranges property */
/* PCI #address-cells == 3 and #size-cells == 2 always */
res = &dev->resource[PCI_BRIDGE_RESOURCES];
for (i = 0; i < PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES; ++i) {
res->flags = 0;
bus->resource[i] = res;
++res;
}
i = 1;
for (; len >= 32; len -= 32, ranges += 8) {
flags = pci_parse_of_flags(of_read_number(ranges, 1), 1);
size = of_read_number(&ranges[6], 2);
if (flags == 0 || size == 0)
continue;
if (flags & IORESOURCE_IO) {
res = bus->resource[0];
if (res->flags) {
printk(KERN_ERR "PCI: ignoring extra I/O range"
" for bridge %s\n", node->full_name);
continue;
}
} else {
if (i >= PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES) {
printk(KERN_ERR "PCI: too many memory ranges"
" for bridge %s\n", node->full_name);
continue;
}
res = bus->resource[i];
++i;
}
res->flags = flags;
region.start = of_read_number(&ranges[1], 2);
region.end = region.start + size - 1;
pcibios_bus_to_resource(dev->bus, res, ®ion);
}
sprintf(bus->name, "PCI Bus %04x:%02x", pci_domain_nr(bus),
bus->number);
pr_debug(" bus name: %s\n", bus->name);
mode = PCI_PROBE_NORMAL;
if (ppc_md.pci_probe_mode)
mode = ppc_md.pci_probe_mode(bus);
pr_debug(" probe mode: %d\n", mode);
if (mode == PCI_PROBE_DEVTREE)
of_scan_bus(node, bus);
else if (mode == PCI_PROBE_NORMAL)
pci_scan_child_bus(bus);
}
EXPORT_SYMBOL(of_scan_pci_bridge);
static struct pci_dev *of_scan_pci_dev(struct pci_bus *bus,
struct device_node *dn)
{
struct pci_dev *dev = NULL;
const __be32 *reg;
int reglen, devfn;
#ifdef CONFIG_EEH
struct eeh_dev *edev = of_node_to_eeh_dev(dn);
#endif
pr_debug(" * %s\n", dn->full_name);
if (!of_device_is_available(dn))
return NULL;
reg = of_get_property(dn, "reg", ®len);
if (reg == NULL || reglen < 20)
return NULL;
devfn = (of_read_number(reg, 1) >> 8) & 0xff;
/* Check if the PCI device is already there */
dev = pci_get_slot(bus, devfn);
if (dev) {
pci_dev_put(dev);
return dev;
}
/* Device removed permanently ? */
#ifdef CONFIG_EEH
if (edev && (edev->mode & EEH_DEV_REMOVED))
return NULL;
#endif
/* create a new pci_dev for this device */
dev = of_create_pci_dev(dn, bus, devfn);
if (!dev)
return NULL;
pr_debug(" dev header type: %x\n", dev->hdr_type);
return dev;
}
/**
* __of_scan_bus - given a PCI bus node, setup bus and scan for child devices
* @node: device tree node for the PCI bus
* @bus: pci_bus structure for the PCI bus
* @rescan_existing: Flag indicating bus has already been set up
*/
static void __of_scan_bus(struct device_node *node, struct pci_bus *bus,
int rescan_existing)
{
struct device_node *child;
struct pci_dev *dev;
pr_debug("of_scan_bus(%s) bus no %d...\n",
node->full_name, bus->number);
/* Scan direct children */
for_each_child_of_node(node, child) {
dev = of_scan_pci_dev(bus, child);
if (!dev)
continue;
pr_debug(" dev header type: %x\n", dev->hdr_type);
}
/* Apply all fixups necessary. We don't fixup the bus "self"
* for an existing bridge that is being rescanned
*/
if (!rescan_existing)
pcibios_setup_bus_self(bus);
pcibios_setup_bus_devices(bus);
/* Now scan child busses */
list_for_each_entry(dev, &bus->devices, bus_list) {
if (pci_is_bridge(dev)) {
of_scan_pci_bridge(dev);
}
}
}
/**
* of_scan_bus - given a PCI bus node, setup bus and scan for child devices
* @node: device tree node for the PCI bus
* @bus: pci_bus structure for the PCI bus
*/
void of_scan_bus(struct device_node *node, struct pci_bus *bus)
{
__of_scan_bus(node, bus, 0);
}
EXPORT_SYMBOL_GPL(of_scan_bus);
/**
* of_rescan_bus - given a PCI bus node, scan for child devices
* @node: device tree node for the PCI bus
* @bus: pci_bus structure for the PCI bus
*
* Same as of_scan_bus, but for a pci_bus structure that has already been
* setup.
*/
void of_rescan_bus(struct device_node *node, struct pci_bus *bus)
{
__of_scan_bus(node, bus, 1);
}
EXPORT_SYMBOL_GPL(of_rescan_bus);