PCI/ACPI: Reserve firmware-allocated resources for hot-added root buses
[deliverable/linux.git] / arch / x86 / pci / i386.c
CommitLineData
1da177e4
LT
1/*
2 * Low-Level PCI Access for i386 machines
3 *
4 * Copyright 1993, 1994 Drew Eckhardt
5 * Visionary Computing
6 * (Unix and Linux consulting and custom programming)
7 * Drew@Colorado.EDU
8 * +1 (303) 786-7975
9 *
10 * Drew's work was sponsored by:
11 * iX Multiuser Multitasking Magazine
12 * Hannover, Germany
13 * hm@ix.de
14 *
15 * Copyright 1997--2000 Martin Mares <mj@ucw.cz>
16 *
17 * For more information, please consult the following manuals (look at
18 * http://www.pcisig.com/ for how to get them):
19 *
20 * PCI BIOS Specification
21 * PCI Local Bus Specification
22 * PCI to PCI Bridge Specification
23 * PCI System Design Guide
24 *
25 */
26
27#include <linux/types.h>
28#include <linux/kernel.h>
69c60c88 29#include <linux/export.h>
1da177e4
LT
30#include <linux/pci.h>
31#include <linux/init.h>
32#include <linux/ioport.h>
33#include <linux/errno.h>
03d72aa1 34#include <linux/bootmem.h>
35
36#include <asm/pat.h>
58f7c988 37#include <asm/e820.h>
82487711 38#include <asm/pci_x86.h>
857fdc53 39#include <asm/io_apic.h>
1da177e4 40
1da177e4 41
925845bd
MS
42/*
43 * This list of dynamic mappings is for temporarily maintaining
44 * original BIOS BAR addresses for possible reinstatement.
45 */
46struct pcibios_fwaddrmap {
47 struct list_head list;
48 struct pci_dev *dev;
49 resource_size_t fw_addr[DEVICE_COUNT_RESOURCE];
50};
51
52static LIST_HEAD(pcibios_fwaddrmappings);
53static DEFINE_SPINLOCK(pcibios_fwaddrmap_lock);
74521602 54static bool pcibios_fw_addr_done;
925845bd
MS
55
56/* Must be called with 'pcibios_fwaddrmap_lock' lock held. */
57static struct pcibios_fwaddrmap *pcibios_fwaddrmap_lookup(struct pci_dev *dev)
58{
59 struct pcibios_fwaddrmap *map;
60
867aae6e 61 WARN_ON_SMP(!spin_is_locked(&pcibios_fwaddrmap_lock));
63ab387c 62
925845bd
MS
63 list_for_each_entry(map, &pcibios_fwaddrmappings, list)
64 if (map->dev == dev)
65 return map;
66
67 return NULL;
68}
69
70static void
71pcibios_save_fw_addr(struct pci_dev *dev, int idx, resource_size_t fw_addr)
72{
73 unsigned long flags;
74 struct pcibios_fwaddrmap *map;
75
74521602
YL
76 if (pcibios_fw_addr_done)
77 return;
78
925845bd
MS
79 spin_lock_irqsave(&pcibios_fwaddrmap_lock, flags);
80 map = pcibios_fwaddrmap_lookup(dev);
81 if (!map) {
82 spin_unlock_irqrestore(&pcibios_fwaddrmap_lock, flags);
83 map = kzalloc(sizeof(*map), GFP_KERNEL);
84 if (!map)
85 return;
86
87 map->dev = pci_dev_get(dev);
88 map->fw_addr[idx] = fw_addr;
89 INIT_LIST_HEAD(&map->list);
90
91 spin_lock_irqsave(&pcibios_fwaddrmap_lock, flags);
92 list_add_tail(&map->list, &pcibios_fwaddrmappings);
93 } else
94 map->fw_addr[idx] = fw_addr;
95 spin_unlock_irqrestore(&pcibios_fwaddrmap_lock, flags);
96}
97
98resource_size_t pcibios_retrieve_fw_addr(struct pci_dev *dev, int idx)
99{
100 unsigned long flags;
101 struct pcibios_fwaddrmap *map;
102 resource_size_t fw_addr = 0;
103
74521602
YL
104 if (pcibios_fw_addr_done)
105 return 0;
106
925845bd
MS
107 spin_lock_irqsave(&pcibios_fwaddrmap_lock, flags);
108 map = pcibios_fwaddrmap_lookup(dev);
109 if (map)
110 fw_addr = map->fw_addr[idx];
111 spin_unlock_irqrestore(&pcibios_fwaddrmap_lock, flags);
112
113 return fw_addr;
114}
115
74521602 116static void __init pcibios_fw_addr_list_del(void)
925845bd
MS
117{
118 unsigned long flags;
119 struct pcibios_fwaddrmap *entry, *next;
120
121 spin_lock_irqsave(&pcibios_fwaddrmap_lock, flags);
122 list_for_each_entry_safe(entry, next, &pcibios_fwaddrmappings, list) {
123 list_del(&entry->list);
124 pci_dev_put(entry->dev);
125 kfree(entry);
126 }
127 spin_unlock_irqrestore(&pcibios_fwaddrmap_lock, flags);
74521602 128 pcibios_fw_addr_done = true;
925845bd
MS
129}
130
036fff4c
GH
131static int
132skip_isa_ioresource_align(struct pci_dev *dev) {
133
134 if ((pci_probe & PCI_CAN_SKIP_ISA_ALIGN) &&
11949255 135 !(dev->bus->bridge_ctl & PCI_BRIDGE_CTL_ISA))
036fff4c
GH
136 return 1;
137 return 0;
138}
139
1da177e4
LT
140/*
141 * We need to avoid collisions with `mirrored' VGA ports
142 * and other strange ISA hardware, so we always want the
143 * addresses to be allocated in the 0x000-0x0ff region
144 * modulo 0x400.
145 *
146 * Why? Because some silly external IO cards only decode
147 * the low 10 bits of the IO address. The 0x00-0xff region
148 * is reserved for motherboard devices that decode all 16
149 * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
150 * but we want to try to avoid allocating at 0x2900-0x2bff
151 * which might have be mirrored at 0x0100-0x03ff..
152 */
b26b2d49 153resource_size_t
3b7a17fc 154pcibios_align_resource(void *data, const struct resource *res,
e31dd6e4 155 resource_size_t size, resource_size_t align)
1da177e4 156{
036fff4c 157 struct pci_dev *dev = data;
d14125ec 158 resource_size_t start = res->start;
036fff4c 159
1da177e4 160 if (res->flags & IORESOURCE_IO) {
d14125ec
BH
161 if (skip_isa_ioresource_align(dev))
162 return start;
163 if (start & 0x300)
164 start = (start + 0x3ff) & ~0x3ff;
1da177e4 165 }
b26b2d49 166 return start;
1da177e4 167}
6c00a61e 168EXPORT_SYMBOL(pcibios_align_resource);
1da177e4
LT
169
170/*
171 * Handle resources of PCI devices. If the world were perfect, we could
172 * just allocate all the resource regions and do nothing more. It isn't.
173 * On the other hand, we cannot just re-allocate all devices, as it would
174 * require us to know lots of host bridge internals. So we attempt to
175 * keep as much of the original configuration as possible, but tweak it
176 * when it's found to be wrong.
177 *
178 * Known BIOS problems we have to work around:
179 * - I/O or memory regions not configured
180 * - regions configured, but not enabled in the command register
181 * - bogus I/O addresses above 64K used
182 * - expansion ROMs left enabled (this may sound harmless, but given
183 * the fact the PCI specs explicitly allow address decoders to be
184 * shared between expansion ROMs and other resource regions, it's
185 * at least dangerous)
837c4ef1 186 * - bad resource sizes or overlaps with other regions
1da177e4
LT
187 *
188 * Our solution:
189 * (1) Allocate resources for all buses behind PCI-to-PCI bridges.
190 * This gives us fixed barriers on where we can allocate.
191 * (2) Allocate resources for all enabled devices. If there is
192 * a collision, just mark the resource as unallocated. Also
193 * disable expansion ROMs during this step.
194 * (3) Try to allocate resources for disabled devices. If the
195 * resources were assigned correctly, everything goes well,
196 * if they weren't, they won't disturb allocation of other
197 * resources.
198 * (4) Assign new addresses to resources which were either
199 * not configured at all or misconfigured. If explicitly
200 * requested by the user, configure expansion ROM address
201 * as well.
202 */
203
b95168e0 204static void pcibios_allocate_bridge_resources(struct pci_dev *dev)
1da177e4 205{
1da177e4 206 int idx;
a76117df 207 struct resource *r;
1da177e4 208
f7ac356d
YL
209 for (idx = PCI_BRIDGE_RESOURCES; idx < PCI_NUM_RESOURCES; idx++) {
210 r = &dev->resource[idx];
211 if (!r->flags)
212 continue;
213 if (!r->start || pci_claim_resource(dev, idx) < 0) {
214 /*
215 * Something is wrong with the region.
216 * Invalidate the resource to prevent
217 * child resource allocations in this
218 * range.
219 */
220 r->start = r->end = 0;
221 r->flags = 0;
222 }
223 }
224}
225
b95168e0 226static void pcibios_allocate_bus_resources(struct pci_bus *bus)
f7ac356d 227{
83edc87c 228 struct pci_bus *child;
f7ac356d 229
1da177e4 230 /* Depth-First Search on bus tree */
83edc87c
YL
231 if (bus->self)
232 pcibios_allocate_bridge_resources(bus->self);
233 list_for_each_entry(child, &bus->children, node)
234 pcibios_allocate_bus_resources(child);
1da177e4
LT
235}
236
575939cf
YL
237struct pci_check_idx_range {
238 int start;
239 int end;
240};
241
b95168e0 242static void pcibios_allocate_dev_resources(struct pci_dev *dev, int pass)
1da177e4 243{
575939cf 244 int idx, disabled, i;
1da177e4 245 u16 command;
a76117df 246 struct resource *r;
1da177e4 247
575939cf
YL
248 struct pci_check_idx_range idx_range[] = {
249 { PCI_STD_RESOURCES, PCI_STD_RESOURCE_END },
250#ifdef CONFIG_PCI_IOV
251 { PCI_IOV_RESOURCES, PCI_IOV_RESOURCE_END },
252#endif
253 };
254
c7f4bbc9
YL
255 pci_read_config_word(dev, PCI_COMMAND, &command);
256 for (i = 0; i < ARRAY_SIZE(idx_range); i++)
575939cf 257 for (idx = idx_range[i].start; idx <= idx_range[i].end; idx++) {
1da177e4 258 r = &dev->resource[idx];
c7f4bbc9 259 if (r->parent) /* Already allocated */
1da177e4 260 continue;
c7f4bbc9 261 if (!r->start) /* Address not assigned at all */
1da177e4
LT
262 continue;
263 if (r->flags & IORESOURCE_IO)
264 disabled = !(command & PCI_COMMAND_IO);
265 else
266 disabled = !(command & PCI_COMMAND_MEMORY);
267 if (pass == disabled) {
c7dabef8 268 dev_dbg(&dev->dev,
865df576 269 "BAR %d: reserving %pr (d=%d, p=%d)\n",
c7dabef8 270 idx, r, disabled, pass);
a76117df 271 if (pci_claim_resource(dev, idx) < 0) {
1da177e4 272 /* We'll assign a new address later */
6535943f
MS
273 pcibios_save_fw_addr(dev,
274 idx, r->start);
1da177e4
LT
275 r->end -= r->start;
276 r->start = 0;
277 }
278 }
279 }
c7f4bbc9
YL
280 if (!pass) {
281 r = &dev->resource[PCI_ROM_RESOURCE];
282 if (r->flags & IORESOURCE_ROM_ENABLE) {
283 /* Turn the ROM off, leave the resource region,
284 * but keep it unregistered. */
285 u32 reg;
286 dev_dbg(&dev->dev, "disabling ROM %pR\n", r);
287 r->flags &= ~IORESOURCE_ROM_ENABLE;
288 pci_read_config_dword(dev, dev->rom_base_reg, &reg);
289 pci_write_config_dword(dev, dev->rom_base_reg,
7edab2f0 290 reg & ~PCI_ROM_ADDRESS_ENABLE);
1da177e4
LT
291 }
292 }
293}
294
b95168e0 295static void pcibios_allocate_resources(struct pci_bus *bus, int pass)
c7f4bbc9 296{
83edc87c
YL
297 struct pci_dev *dev;
298 struct pci_bus *child;
c7f4bbc9 299
83edc87c 300 list_for_each_entry(dev, &bus->devices, bus_list) {
c7f4bbc9 301 pcibios_allocate_dev_resources(dev, pass);
83edc87c
YL
302
303 child = dev->subordinate;
304 if (child)
305 pcibios_allocate_resources(child, pass);
306 }
c7f4bbc9
YL
307}
308
b95168e0 309static void pcibios_allocate_dev_rom_resource(struct pci_dev *dev)
1da177e4 310{
a76117df 311 struct resource *r;
1da177e4 312
dc2f56fa
YL
313 /*
314 * Try to use BIOS settings for ROMs, otherwise let
315 * pci_assign_unassigned_resources() allocate the new
316 * addresses.
317 */
318 r = &dev->resource[PCI_ROM_RESOURCE];
319 if (!r->flags || !r->start)
320 return;
321
322 if (pci_claim_resource(dev, PCI_ROM_RESOURCE) < 0) {
323 r->end -= r->start;
324 r->start = 0;
1da177e4 325 }
dc2f56fa 326}
b95168e0 327static void pcibios_allocate_rom_resources(struct pci_bus *bus)
dc2f56fa
YL
328{
329 struct pci_dev *dev;
330 struct pci_bus *child;
331
332 list_for_each_entry(dev, &bus->devices, bus_list) {
333 pcibios_allocate_dev_rom_resource(dev);
334
335 child = dev->subordinate;
336 if (child)
337 pcibios_allocate_rom_resources(child);
338 }
339}
340
341static int __init pcibios_assign_resources(void)
342{
343 struct pci_bus *bus;
344
345 if (!(pci_probe & PCI_ASSIGN_ROMS))
346 list_for_each_entry(bus, &pci_root_buses, node)
347 pcibios_allocate_rom_resources(bus);
81d4af13
IK
348
349 pci_assign_unassigned_resources();
6535943f 350 pcibios_fw_addr_list_del();
81d4af13 351
1da177e4
LT
352 return 0;
353}
354
355void __init pcibios_resource_survey(void)
356{
83edc87c
YL
357 struct pci_bus *bus;
358
1da177e4 359 DBG("PCI: Allocating resources\n");
83edc87c
YL
360
361 list_for_each_entry(bus, &pci_root_buses, node)
362 pcibios_allocate_bus_resources(bus);
363
364 list_for_each_entry(bus, &pci_root_buses, node)
365 pcibios_allocate_resources(bus, 0);
366 list_for_each_entry(bus, &pci_root_buses, node)
367 pcibios_allocate_resources(bus, 1);
a5444d15
IM
368
369 e820_reserve_resources_late();
857fdc53
YL
370 /*
371 * Insert the IO APIC resources after PCI initialization has
0d2eb44f 372 * occurred to handle IO APICS that are mapped in on a BAR in
857fdc53
YL
373 * PCI space, but before trying to assign unassigned pci res.
374 */
375 ioapic_insert_resources();
1da177e4
LT
376}
377
378/**
379 * called in fs_initcall (one below subsys_initcall),
380 * give a chance for motherboard reserve resources
381 */
382fs_initcall(pcibios_assign_resources);
383
f0f37e2f 384static const struct vm_operations_struct pci_mmap_ops = {
7ae8ed50 385 .access = generic_access_phys,
03d72aa1 386};
387
1da177e4
LT
388int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
389 enum pci_mmap_state mmap_state, int write_combine)
390{
391 unsigned long prot;
392
393 /* I/O space cannot be accessed via normal processor loads and
394 * stores on this platform.
395 */
396 if (mmap_state == pci_mmap_io)
397 return -EINVAL;
398
1da177e4 399 prot = pgprot_val(vma->vm_page_prot);
2992e545
SS
400
401 /*
402 * Return error if pat is not enabled and write_combine is requested.
403 * Caller can followup with UC MINUS request and add a WC mtrr if there
404 * is a free mtrr slot.
405 */
406 if (!pat_enabled && write_combine)
407 return -EINVAL;
408
499f8f84 409 if (pat_enabled && write_combine)
03d72aa1 410 prot |= _PAGE_CACHE_WC;
499f8f84 411 else if (pat_enabled || boot_cpu_data.x86 > 3)
de33c442
SS
412 /*
413 * ioremap() and ioremap_nocache() defaults to UC MINUS for now.
414 * To avoid attribute conflicts, request UC MINUS here
0d2eb44f 415 * as well.
de33c442
SS
416 */
417 prot |= _PAGE_CACHE_UC_MINUS;
03d72aa1 418
5ee01f49
JF
419 prot |= _PAGE_IOMAP; /* creating a mapping for IO */
420
1da177e4
LT
421 vma->vm_page_prot = __pgprot(prot);
422
346d3882
MT
423 if (io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
424 vma->vm_end - vma->vm_start,
425 vma->vm_page_prot))
1da177e4
LT
426 return -EAGAIN;
427
03d72aa1 428 vma->vm_ops = &pci_mmap_ops;
429
1da177e4
LT
430 return 0;
431}
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