2 * Low-Level PCI Support for PC
4 * (c) 1999--2000 Martin Mares <mj@ucw.cz>
7 #include <linux/sched.h>
9 #include <linux/ioport.h>
10 #include <linux/init.h>
13 #include <asm/segment.h>
19 #ifdef CONFIG_PCI_BIOS
20 extern void pcibios_sort(void);
23 unsigned int pci_probe = PCI_PROBE_BIOS | PCI_PROBE_CONF1 | PCI_PROBE_CONF2 |
26 int pcibios_last_bus = -1;
27 struct pci_bus *pci_root_bus = NULL;
28 struct pci_raw_ops *raw_pci_ops;
30 static int pci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *value)
32 return raw_pci_ops->read(0, bus->number, devfn, where, size, value);
35 static int pci_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 value)
37 return raw_pci_ops->write(0, bus->number, devfn, where, size, value);
40 struct pci_ops pci_root_ops = {
46 * legacy, numa, and acpi all want to call pcibios_scan_root
47 * from their initcalls. This flag prevents that.
52 * This interrupt-safe spinlock protects all accesses to PCI
53 * configuration space.
55 spinlock_t pci_config_lock = SPIN_LOCK_UNLOCKED;
58 * Several buggy motherboards address only 16 devices and mirror
59 * them to next 16 IDs. We try to detect this `feature' on all
60 * primary buses (those containing host bridges as they are
61 * expected to be unique) and remove the ghost devices.
64 static void __devinit pcibios_fixup_ghosts(struct pci_bus *b)
66 struct list_head *ln, *mn;
67 struct pci_dev *d, *e;
68 int mirror = PCI_DEVFN(16,0);
69 int seen_host_bridge = 0;
72 DBG("PCI: Scanning for ghost devices on bus %d\n", b->number);
73 list_for_each(ln, &b->devices) {
75 if ((d->class >> 8) == PCI_CLASS_BRIDGE_HOST)
77 for (mn=ln->next; mn != &b->devices; mn=mn->next) {
79 if (e->devfn != d->devfn + mirror ||
80 e->vendor != d->vendor ||
81 e->device != d->device ||
84 for(i=0; i<PCI_NUM_RESOURCES; i++)
85 if (e->resource[i].start != d->resource[i].start ||
86 e->resource[i].end != d->resource[i].end ||
87 e->resource[i].flags != d->resource[i].flags)
91 if (mn == &b->devices)
94 if (!seen_host_bridge)
96 printk(KERN_WARNING "PCI: Ignoring ghost devices on bus %02x\n", b->number);
99 while (ln->next != &b->devices) {
100 d = pci_dev_b(ln->next);
101 if (d->devfn >= mirror) {
102 list_del(&d->global_list);
103 list_del(&d->bus_list);
111 * Called after each bus is probed, but before its children
115 void __devinit pcibios_fixup_bus(struct pci_bus *b)
117 pcibios_fixup_ghosts(b);
118 pci_read_bridge_bases(b);
122 struct pci_bus * __devinit pcibios_scan_root(int busnum)
124 struct pci_bus *bus = NULL;
126 while ((bus = pci_find_next_bus(bus)) != NULL) {
127 if (bus->number == busnum) {
128 /* Already scanned */
133 printk("PCI: Probing PCI hardware (bus %02x)\n", busnum);
135 return pci_scan_bus(busnum, &pci_root_ops, NULL);
138 extern u8 pci_cache_line_size;
140 static int __init pcibios_init(void)
142 struct cpuinfo_x86 *c = &boot_cpu_data;
145 printk("PCI: System does not support PCI\n");
150 * Assume PCI cacheline size of 32 bytes for all x86s except K7/K8
151 * and P4. It's also good for 386/486s (which actually have 16)
152 * as quite a few PCI devices do not support smaller values.
154 pci_cache_line_size = 32 >> 2;
155 if (c->x86 >= 6 && c->x86_vendor == X86_VENDOR_AMD)
156 pci_cache_line_size = 64 >> 2; /* K7 & K8 */
157 else if (c->x86 > 6 && c->x86_vendor == X86_VENDOR_INTEL)
158 pci_cache_line_size = 128 >> 2; /* P4 */
160 pcibios_resource_survey();
162 #ifdef CONFIG_PCI_BIOS
163 if ((pci_probe & PCI_BIOS_SORT) && !(pci_probe & PCI_NO_SORT))
169 subsys_initcall(pcibios_init);
171 char * __devinit pcibios_setup(char *str)
173 if (!strcmp(str, "off")) {
177 #ifdef CONFIG_PCI_BIOS
178 else if (!strcmp(str, "bios")) {
179 pci_probe = PCI_PROBE_BIOS;
181 } else if (!strcmp(str, "nobios")) {
182 pci_probe &= ~PCI_PROBE_BIOS;
184 } else if (!strcmp(str, "nosort")) {
185 pci_probe |= PCI_NO_SORT;
187 } else if (!strcmp(str, "biosirq")) {
188 pci_probe |= PCI_BIOS_IRQ_SCAN;
192 #ifdef CONFIG_PCI_DIRECT
193 else if (!strcmp(str, "conf1")) {
194 pci_probe = PCI_PROBE_CONF1 | PCI_NO_CHECKS;
197 else if (!strcmp(str, "conf2")) {
198 pci_probe = PCI_PROBE_CONF2 | PCI_NO_CHECKS;
202 #ifdef CONFIG_PCI_MMCONFIG
203 else if (!strcmp(str, "nommconf")) {
204 pci_probe &= ~PCI_PROBE_MMCONF;
208 else if (!strcmp(str, "noacpi")) {
212 #ifndef CONFIG_X86_VISWS
213 else if (!strcmp(str, "usepirqmask")) {
214 pci_probe |= PCI_USE_PIRQ_MASK;
216 } else if (!strncmp(str, "irqmask=", 8)) {
217 pcibios_irq_mask = simple_strtol(str+8, NULL, 0);
219 } else if (!strncmp(str, "lastbus=", 8)) {
220 pcibios_last_bus = simple_strtol(str+8, NULL, 0);
224 else if (!strcmp(str, "rom")) {
225 pci_probe |= PCI_ASSIGN_ROMS;
227 } else if (!strcmp(str, "assign-busses")) {
228 pci_probe |= PCI_ASSIGN_ALL_BUSSES;
234 unsigned int pcibios_assign_all_busses(void)
236 return (pci_probe & PCI_ASSIGN_ALL_BUSSES) ? 1 : 0;
239 int pcibios_enable_device(struct pci_dev *dev, int mask)
243 if ((err = pcibios_enable_resources(dev, mask)) < 0)
246 return pcibios_enable_irq(dev);