2 * Helper routines to scan the device tree for PCI devices and busses
4 * Migrated out of PowerPC architecture pci_64.c file by Grant Likely
5 * <grant.likely@secretlab.ca> so that these routines are available for
8 * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
9 * Rework, based on alpha PCI code.
10 * Copyright (c) 2009 Secret Lab Technologies Ltd.
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * version 2 as published by the Free Software Foundation.
17 #include <linux/pci.h>
18 #include <linux/export.h>
19 #include <asm/pci-bridge.h>
23 * get_int_prop - Decode a u32 from a device tree property
25 static u32 get_int_prop(struct device_node *np, const char *name, u32 def)
30 prop = of_get_property(np, name, &len);
32 return of_read_number(prop, 1);
37 * pci_parse_of_flags - Parse the flags cell of a device tree PCI address
38 * @addr0: value of 1st cell of a device tree PCI address.
39 * @bridge: Set this flag if the address is from a bridge 'ranges' property
41 unsigned int pci_parse_of_flags(u32 addr0, int bridge)
43 unsigned int flags = 0;
45 if (addr0 & 0x02000000) {
46 flags = IORESOURCE_MEM | PCI_BASE_ADDRESS_SPACE_MEMORY;
47 flags |= (addr0 >> 22) & PCI_BASE_ADDRESS_MEM_TYPE_64;
48 if (flags & PCI_BASE_ADDRESS_MEM_TYPE_64)
49 flags |= IORESOURCE_MEM_64;
50 flags |= (addr0 >> 28) & PCI_BASE_ADDRESS_MEM_TYPE_1M;
51 if (addr0 & 0x40000000)
52 flags |= IORESOURCE_PREFETCH
53 | PCI_BASE_ADDRESS_MEM_PREFETCH;
54 /* Note: We don't know whether the ROM has been left enabled
55 * by the firmware or not. We mark it as disabled (ie, we do
56 * not set the IORESOURCE_ROM_ENABLE flag) for now rather than
57 * do a config space read, it will be force-enabled if needed
59 if (!bridge && (addr0 & 0xff) == 0x30)
60 flags |= IORESOURCE_READONLY;
61 } else if (addr0 & 0x01000000)
62 flags = IORESOURCE_IO | PCI_BASE_ADDRESS_SPACE_IO;
64 flags |= IORESOURCE_SIZEALIGN;
69 * of_pci_parse_addrs - Parse PCI addresses assigned in the device tree node
70 * @node: device tree node for the PCI device
71 * @dev: pci_dev structure for the device
73 * This function parses the 'assigned-addresses' property of a PCI devices'
74 * device tree node and writes them into the associated pci_dev structure.
76 static void of_pci_parse_addrs(struct device_node *node, struct pci_dev *dev)
80 struct pci_bus_region region;
86 addrs = of_get_property(node, "assigned-addresses", &proplen);
89 pr_debug(" parse addresses (%d bytes) @ %p\n", proplen, addrs);
90 for (; proplen >= 20; proplen -= 20, addrs += 5) {
91 flags = pci_parse_of_flags(of_read_number(addrs, 1), 0);
94 base = of_read_number(&addrs[1], 2);
95 size = of_read_number(&addrs[3], 2);
98 i = of_read_number(addrs, 1) & 0xff;
99 pr_debug(" base: %llx, size: %llx, i: %x\n",
100 (unsigned long long)base,
101 (unsigned long long)size, i);
103 if (PCI_BASE_ADDRESS_0 <= i && i <= PCI_BASE_ADDRESS_5) {
104 res = &dev->resource[(i - PCI_BASE_ADDRESS_0) >> 2];
105 } else if (i == dev->rom_base_reg) {
106 res = &dev->resource[PCI_ROM_RESOURCE];
107 flags |= IORESOURCE_READONLY;
109 printk(KERN_ERR "PCI: bad cfg reg num 0x%x\n", i);
113 res->name = pci_name(dev);
115 region.end = base + size - 1;
116 pcibios_bus_to_resource(dev->bus, res, ®ion);
121 * of_create_pci_dev - Given a device tree node on a pci bus, create a pci_dev
122 * @node: device tree node pointer
123 * @bus: bus the device is sitting on
124 * @devfn: PCI function number, extracted from device tree by caller.
126 struct pci_dev *of_create_pci_dev(struct device_node *node,
127 struct pci_bus *bus, int devfn)
131 dev = pci_alloc_dev(bus);
135 pr_debug(" create device, devfn: %x, type: %s\n", devfn,
136 of_node_get_device_type(node));
138 dev->dev.of_node = of_node_get(node);
139 dev->dev.parent = bus->bridge;
140 dev->dev.bus = &pci_bus_type;
142 dev->multifunction = 0; /* maybe a lie? */
143 dev->needs_freset = 0; /* pcie fundamental reset required */
144 set_pcie_port_type(dev);
146 pci_dev_assign_slot(dev);
147 dev->vendor = get_int_prop(node, "vendor-id", 0xffff);
148 dev->device = get_int_prop(node, "device-id", 0xffff);
149 dev->subsystem_vendor = get_int_prop(node, "subsystem-vendor-id", 0);
150 dev->subsystem_device = get_int_prop(node, "subsystem-id", 0);
152 dev->cfg_size = pci_cfg_space_size(dev);
154 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(bus),
155 dev->bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn));
156 dev->class = get_int_prop(node, "class-code", 0);
157 dev->revision = get_int_prop(node, "revision-id", 0);
159 pr_debug(" class: 0x%x\n", dev->class);
160 pr_debug(" revision: 0x%x\n", dev->revision);
162 dev->current_state = PCI_UNKNOWN; /* unknown power state */
163 dev->error_state = pci_channel_io_normal;
164 dev->dma_mask = 0xffffffff;
166 /* Early fixups, before probing the BARs */
167 pci_fixup_device(pci_fixup_early, dev);
169 if (of_node_is_type(node, "pci") || of_node_is_type(node, "pciex")) {
170 /* a PCI-PCI bridge */
171 dev->hdr_type = PCI_HEADER_TYPE_BRIDGE;
172 dev->rom_base_reg = PCI_ROM_ADDRESS1;
173 set_pcie_hotplug_bridge(dev);
174 } else if (of_node_is_type(node, "cardbus")) {
175 dev->hdr_type = PCI_HEADER_TYPE_CARDBUS;
177 dev->hdr_type = PCI_HEADER_TYPE_NORMAL;
178 dev->rom_base_reg = PCI_ROM_ADDRESS;
179 /* Maybe do a default OF mapping here */
183 of_pci_parse_addrs(node, dev);
185 pr_debug(" adding to system ...\n");
187 pci_device_add(dev, bus);
191 EXPORT_SYMBOL(of_create_pci_dev);
194 * of_scan_pci_bridge - Set up a PCI bridge and scan for child nodes
195 * @dev: pci_dev structure for the bridge
197 * of_scan_bus() calls this routine for each PCI bridge that it finds, and
198 * this routine in turn call of_scan_bus() recusively to scan for more child
201 void of_scan_pci_bridge(struct pci_dev *dev)
203 struct device_node *node = dev->dev.of_node;
205 struct pci_controller *phb;
206 const __be32 *busrange, *ranges;
208 struct pci_bus_region region;
209 struct resource *res;
213 pr_debug("of_scan_pci_bridge(%pOF)\n", node);
215 /* parse bus-range property */
216 busrange = of_get_property(node, "bus-range", &len);
217 if (busrange == NULL || len != 8) {
218 printk(KERN_DEBUG "Can't get bus-range for PCI-PCI bridge %pOF\n",
222 ranges = of_get_property(node, "ranges", &len);
223 if (ranges == NULL) {
224 printk(KERN_DEBUG "Can't get ranges for PCI-PCI bridge %pOF\n",
229 bus = pci_find_bus(pci_domain_nr(dev->bus),
230 of_read_number(busrange, 1));
232 bus = pci_add_new_bus(dev->bus, dev,
233 of_read_number(busrange, 1));
235 printk(KERN_ERR "Failed to create pci bus for %pOF\n",
241 bus->primary = dev->bus->number;
242 pci_bus_insert_busn_res(bus, of_read_number(busrange, 1),
243 of_read_number(busrange+1, 1));
246 /* parse ranges property */
247 /* PCI #address-cells == 3 and #size-cells == 2 always */
248 res = &dev->resource[PCI_BRIDGE_RESOURCES];
249 for (i = 0; i < PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES; ++i) {
251 bus->resource[i] = res;
255 for (; len >= 32; len -= 32, ranges += 8) {
256 flags = pci_parse_of_flags(of_read_number(ranges, 1), 1);
257 size = of_read_number(&ranges[6], 2);
258 if (flags == 0 || size == 0)
260 if (flags & IORESOURCE_IO) {
261 res = bus->resource[0];
263 printk(KERN_ERR "PCI: ignoring extra I/O range"
264 " for bridge %pOF\n", node);
268 if (i >= PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES) {
269 printk(KERN_ERR "PCI: too many memory ranges"
270 " for bridge %pOF\n", node);
273 res = bus->resource[i];
277 region.start = of_read_number(&ranges[1], 2);
278 region.end = region.start + size - 1;
279 pcibios_bus_to_resource(dev->bus, res, ®ion);
281 sprintf(bus->name, "PCI Bus %04x:%02x", pci_domain_nr(bus),
283 pr_debug(" bus name: %s\n", bus->name);
285 phb = pci_bus_to_host(bus);
287 mode = PCI_PROBE_NORMAL;
288 if (phb->controller_ops.probe_mode)
289 mode = phb->controller_ops.probe_mode(bus);
290 pr_debug(" probe mode: %d\n", mode);
292 if (mode == PCI_PROBE_DEVTREE)
293 of_scan_bus(node, bus);
294 else if (mode == PCI_PROBE_NORMAL)
295 pci_scan_child_bus(bus);
297 EXPORT_SYMBOL(of_scan_pci_bridge);
299 static struct pci_dev *of_scan_pci_dev(struct pci_bus *bus,
300 struct device_node *dn)
302 struct pci_dev *dev = NULL;
306 struct eeh_dev *edev = pdn_to_eeh_dev(PCI_DN(dn));
309 pr_debug(" * %pOF\n", dn);
310 if (!of_device_is_available(dn))
313 reg = of_get_property(dn, "reg", ®len);
314 if (reg == NULL || reglen < 20)
316 devfn = (of_read_number(reg, 1) >> 8) & 0xff;
318 /* Check if the PCI device is already there */
319 dev = pci_get_slot(bus, devfn);
325 /* Device removed permanently ? */
327 if (edev && (edev->mode & EEH_DEV_REMOVED))
331 /* create a new pci_dev for this device */
332 dev = of_create_pci_dev(dn, bus, devfn);
336 pr_debug(" dev header type: %x\n", dev->hdr_type);
341 * __of_scan_bus - given a PCI bus node, setup bus and scan for child devices
342 * @node: device tree node for the PCI bus
343 * @bus: pci_bus structure for the PCI bus
344 * @rescan_existing: Flag indicating bus has already been set up
346 static void __of_scan_bus(struct device_node *node, struct pci_bus *bus,
349 struct device_node *child;
352 pr_debug("of_scan_bus(%pOF) bus no %d...\n",
355 /* Scan direct children */
356 for_each_child_of_node(node, child) {
357 dev = of_scan_pci_dev(bus, child);
360 pr_debug(" dev header type: %x\n", dev->hdr_type);
363 /* Apply all fixups necessary. We don't fixup the bus "self"
364 * for an existing bridge that is being rescanned
366 if (!rescan_existing)
367 pcibios_setup_bus_self(bus);
368 pcibios_setup_bus_devices(bus);
370 /* Now scan child busses */
371 for_each_pci_bridge(dev, bus)
372 of_scan_pci_bridge(dev);
376 * of_scan_bus - given a PCI bus node, setup bus and scan for child devices
377 * @node: device tree node for the PCI bus
378 * @bus: pci_bus structure for the PCI bus
380 void of_scan_bus(struct device_node *node, struct pci_bus *bus)
382 __of_scan_bus(node, bus, 0);
384 EXPORT_SYMBOL_GPL(of_scan_bus);
387 * of_rescan_bus - given a PCI bus node, scan for child devices
388 * @node: device tree node for the PCI bus
389 * @bus: pci_bus structure for the PCI bus
391 * Same as of_scan_bus, but for a pci_bus structure that has already been
394 void of_rescan_bus(struct device_node *node, struct pci_bus *bus)
396 __of_scan_bus(node, bus, 1);
398 EXPORT_SYMBOL_GPL(of_rescan_bus);