tjh.dev
Linux kernel mirror (for testing)
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linux
1/*
2 * PCI autoconfiguration library
3 *
4 * Author: Matt Porter <mporter@mvista.com>
5 *
6 * 2001 (c) MontaVista, Software, Inc. This file is licensed under
7 * the terms of the GNU General Public License version 2. This program
8 * is licensed "as is" without any warranty of any kind, whether express
9 * or implied.
10 */
11
12/*
13 * The CardBus support is very preliminary. Preallocating space is
14 * the way to go but will require some change in card services to
15 * make it useful. Eventually this will ensure that we can put
16 * multiple CB bridges behind multiple P2P bridges. For now, at
17 * least it ensures that we place the CB bridge BAR and assigned
18 * initial bus numbers. I definitely need to do something about
19 * the lack of 16-bit I/O support. -MDP
20 */
21
22#include <linux/kernel.h>
23#include <linux/init.h>
24#include <linux/pci.h>
25
26#include <asm/pci-bridge.h>
27
28#define PCIAUTO_IDE_MODE_MASK 0x05
29
30#undef DEBUG
31
32#ifdef DEBUG
33#define DBG(x...) printk(x)
34#else
35#define DBG(x...)
36#endif /* DEBUG */
37
38static int pciauto_upper_iospc;
39static int pciauto_upper_memspc;
40
41void __init pciauto_setup_bars(struct pci_controller *hose,
42 int current_bus,
43 int pci_devfn,
44 int bar_limit)
45{
46 int bar_response, bar_size, bar_value;
47 int bar, addr_mask;
48 int * upper_limit;
49 int found_mem64 = 0;
50
51 DBG("PCI Autoconfig: Found Bus %d, Device %d, Function %d\n",
52 current_bus, PCI_SLOT(pci_devfn), PCI_FUNC(pci_devfn) );
53
54 for (bar = PCI_BASE_ADDRESS_0; bar <= bar_limit; bar+=4) {
55 /* Tickle the BAR and get the response */
56 early_write_config_dword(hose,
57 current_bus,
58 pci_devfn,
59 bar,
60 0xffffffff);
61 early_read_config_dword(hose,
62 current_bus,
63 pci_devfn,
64 bar,
65 &bar_response);
66
67 /* If BAR is not implemented go to the next BAR */
68 if (!bar_response)
69 continue;
70
71 /* Check the BAR type and set our address mask */
72 if (bar_response & PCI_BASE_ADDRESS_SPACE) {
73 addr_mask = PCI_BASE_ADDRESS_IO_MASK;
74 upper_limit = &pciauto_upper_iospc;
75 DBG("PCI Autoconfig: BAR 0x%x, I/O, ", bar);
76 } else {
77 if ( (bar_response & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
78 PCI_BASE_ADDRESS_MEM_TYPE_64)
79 found_mem64 = 1;
80
81 addr_mask = PCI_BASE_ADDRESS_MEM_MASK;
82 upper_limit = &pciauto_upper_memspc;
83 DBG("PCI Autoconfig: BAR 0x%x, Mem ", bar);
84 }
85
86 /* Calculate requested size */
87 bar_size = ~(bar_response & addr_mask) + 1;
88
89 /* Allocate a base address */
90 bar_value = (*upper_limit - bar_size) & ~(bar_size - 1);
91
92 /* Write it out and update our limit */
93 early_write_config_dword(hose,
94 current_bus,
95 pci_devfn,
96 bar,
97 bar_value);
98
99 *upper_limit = bar_value;
100
101 /*
102 * If we are a 64-bit decoder then increment to the
103 * upper 32 bits of the bar and force it to locate
104 * in the lower 4GB of memory.
105 */
106 if (found_mem64) {
107 bar += 4;
108 early_write_config_dword(hose,
109 current_bus,
110 pci_devfn,
111 bar,
112 0x00000000);
113 found_mem64 = 0;
114 }
115
116 DBG("size=0x%x, address=0x%x\n",
117 bar_size, bar_value);
118 }
119
120}
121
122void __init pciauto_prescan_setup_bridge(struct pci_controller *hose,
123 int current_bus,
124 int pci_devfn,
125 int sub_bus,
126 int *iosave,
127 int *memsave)
128{
129 /* Configure bus number registers */
130 early_write_config_byte(hose,
131 current_bus,
132 pci_devfn,
133 PCI_PRIMARY_BUS,
134 current_bus);
135 early_write_config_byte(hose,
136 current_bus,
137 pci_devfn,
138 PCI_SECONDARY_BUS,
139 sub_bus + 1);
140 early_write_config_byte(hose,
141 current_bus,
142 pci_devfn,
143 PCI_SUBORDINATE_BUS,
144 0xff);
145
146 /* Round memory allocator to 1MB boundary */
147 pciauto_upper_memspc &= ~(0x100000 - 1);
148 *memsave = pciauto_upper_memspc;
149
150 /* Round I/O allocator to 4KB boundary */
151 pciauto_upper_iospc &= ~(0x1000 - 1);
152 *iosave = pciauto_upper_iospc;
153
154 /* Set up memory and I/O filter limits, assume 32-bit I/O space */
155 early_write_config_word(hose,
156 current_bus,
157 pci_devfn,
158 PCI_MEMORY_LIMIT,
159 ((pciauto_upper_memspc - 1) & 0xfff00000) >> 16);
160 early_write_config_byte(hose,
161 current_bus,
162 pci_devfn,
163 PCI_IO_LIMIT,
164 ((pciauto_upper_iospc - 1) & 0x0000f000) >> 8);
165 early_write_config_word(hose,
166 current_bus,
167 pci_devfn,
168 PCI_IO_LIMIT_UPPER16,
169 ((pciauto_upper_iospc - 1) & 0xffff0000) >> 16);
170
171 /* Zero upper 32 bits of prefetchable base/limit */
172 early_write_config_dword(hose,
173 current_bus,
174 pci_devfn,
175 PCI_PREF_BASE_UPPER32,
176 0);
177 early_write_config_dword(hose,
178 current_bus,
179 pci_devfn,
180 PCI_PREF_LIMIT_UPPER32,
181 0);
182}
183
184void __init pciauto_postscan_setup_bridge(struct pci_controller *hose,
185 int current_bus,
186 int pci_devfn,
187 int sub_bus,
188 int *iosave,
189 int *memsave)
190{
191 int cmdstat;
192
193 /* Configure bus number registers */
194 early_write_config_byte(hose,
195 current_bus,
196 pci_devfn,
197 PCI_SUBORDINATE_BUS,
198 sub_bus);
199
200 /*
201 * Round memory allocator to 1MB boundary.
202 * If no space used, allocate minimum.
203 */
204 pciauto_upper_memspc &= ~(0x100000 - 1);
205 if (*memsave == pciauto_upper_memspc)
206 pciauto_upper_memspc -= 0x00100000;
207
208 early_write_config_word(hose,
209 current_bus,
210 pci_devfn,
211 PCI_MEMORY_BASE,
212 pciauto_upper_memspc >> 16);
213
214 /* Allocate 1MB for pre-fretch */
215 early_write_config_word(hose,
216 current_bus,
217 pci_devfn,
218 PCI_PREF_MEMORY_LIMIT,
219 ((pciauto_upper_memspc - 1) & 0xfff00000) >> 16);
220
221 pciauto_upper_memspc -= 0x100000;
222
223 early_write_config_word(hose,
224 current_bus,
225 pci_devfn,
226 PCI_PREF_MEMORY_BASE,
227 pciauto_upper_memspc >> 16);
228
229 /* Round I/O allocator to 4KB boundary */
230 pciauto_upper_iospc &= ~(0x1000 - 1);
231 if (*iosave == pciauto_upper_iospc)
232 pciauto_upper_iospc -= 0x1000;
233
234 early_write_config_byte(hose,
235 current_bus,
236 pci_devfn,
237 PCI_IO_BASE,
238 (pciauto_upper_iospc & 0x0000f000) >> 8);
239 early_write_config_word(hose,
240 current_bus,
241 pci_devfn,
242 PCI_IO_BASE_UPPER16,
243 pciauto_upper_iospc >> 16);
244
245 /* Enable memory and I/O accesses, enable bus master */
246 early_read_config_dword(hose,
247 current_bus,
248 pci_devfn,
249 PCI_COMMAND,
250 &cmdstat);
251 early_write_config_dword(hose,
252 current_bus,
253 pci_devfn,
254 PCI_COMMAND,
255 cmdstat |
256 PCI_COMMAND_IO |
257 PCI_COMMAND_MEMORY |
258 PCI_COMMAND_MASTER);
259}
260
261void __init pciauto_prescan_setup_cardbus_bridge(struct pci_controller *hose,
262 int current_bus,
263 int pci_devfn,
264 int sub_bus,
265 int *iosave,
266 int *memsave)
267{
268 /* Configure bus number registers */
269 early_write_config_byte(hose,
270 current_bus,
271 pci_devfn,
272 PCI_PRIMARY_BUS,
273 current_bus);
274 early_write_config_byte(hose,
275 current_bus,
276 pci_devfn,
277 PCI_SECONDARY_BUS,
278 sub_bus + 1);
279 early_write_config_byte(hose,
280 current_bus,
281 pci_devfn,
282 PCI_SUBORDINATE_BUS,
283 0xff);
284
285 /* Round memory allocator to 4KB boundary */
286 pciauto_upper_memspc &= ~(0x1000 - 1);
287 *memsave = pciauto_upper_memspc;
288
289 /* Round I/O allocator to 4 byte boundary */
290 pciauto_upper_iospc &= ~(0x4 - 1);
291 *iosave = pciauto_upper_iospc;
292
293 /* Set up memory and I/O filter limits, assume 32-bit I/O space */
294 early_write_config_dword(hose,
295 current_bus,
296 pci_devfn,
297 0x20,
298 pciauto_upper_memspc - 1);
299 early_write_config_dword(hose,
300 current_bus,
301 pci_devfn,
302 0x30,
303 pciauto_upper_iospc - 1);
304}
305
306void __init pciauto_postscan_setup_cardbus_bridge(struct pci_controller *hose,
307 int current_bus,
308 int pci_devfn,
309 int sub_bus,
310 int *iosave,
311 int *memsave)
312{
313 int cmdstat;
314
315 /*
316 * Configure subordinate bus number. The PCI subsystem
317 * bus scan will renumber buses (reserving three additional
318 * for this PCI<->CardBus bridge for the case where a CardBus
319 * adapter contains a P2P or CB2CB bridge.
320 */
321 early_write_config_byte(hose,
322 current_bus,
323 pci_devfn,
324 PCI_SUBORDINATE_BUS,
325 sub_bus);
326
327 /*
328 * Reserve an additional 4MB for mem space and 16KB for
329 * I/O space. This should cover any additional space
330 * requirement of unusual CardBus devices with
331 * additional bridges that can consume more address space.
332 *
333 * Although pcmcia-cs currently will reprogram bridge
334 * windows, the goal is to add an option to leave them
335 * alone and use the bridge window ranges as the regions
336 * that are searched for free resources upon hot-insertion
337 * of a device. This will allow a PCI<->CardBus bridge
338 * configured by this routine to happily live behind a
339 * P2P bridge in a system.
340 */
341 pciauto_upper_memspc -= 0x00400000;
342 pciauto_upper_iospc -= 0x00004000;
343
344 /* Round memory allocator to 4KB boundary */
345 pciauto_upper_memspc &= ~(0x1000 - 1);
346
347 early_write_config_dword(hose,
348 current_bus,
349 pci_devfn,
350 0x1c,
351 pciauto_upper_memspc);
352
353 /* Round I/O allocator to 4 byte boundary */
354 pciauto_upper_iospc &= ~(0x4 - 1);
355 early_write_config_dword(hose,
356 current_bus,
357 pci_devfn,
358 0x2c,
359 pciauto_upper_iospc);
360
361 /* Enable memory and I/O accesses, enable bus master */
362 early_read_config_dword(hose,
363 current_bus,
364 pci_devfn,
365 PCI_COMMAND,
366 &cmdstat);
367 early_write_config_dword(hose,
368 current_bus,
369 pci_devfn,
370 PCI_COMMAND,
371 cmdstat |
372 PCI_COMMAND_IO |
373 PCI_COMMAND_MEMORY |
374 PCI_COMMAND_MASTER);
375}
376
377int __init pciauto_bus_scan(struct pci_controller *hose, int current_bus)
378{
379 int sub_bus, pci_devfn, pci_class, cmdstat, found_multi = 0;
380 unsigned short vid;
381 unsigned char header_type;
382
383 /*
384 * Fetch our I/O and memory space upper boundaries used
385 * to allocated base addresses on this hose.
386 */
387 if (current_bus == hose->first_busno) {
388 pciauto_upper_iospc = hose->io_space.end + 1;
389 pciauto_upper_memspc = hose->mem_space.end + 1;
390 }
391
392 sub_bus = current_bus;
393
394 for (pci_devfn = 0; pci_devfn < 0xff; pci_devfn++) {
395 /* Skip our host bridge */
396 if ( (current_bus == hose->first_busno) && (pci_devfn == 0) )
397 continue;
398
399 if (PCI_FUNC(pci_devfn) && !found_multi)
400 continue;
401
402 /* If config space read fails from this device, move on */
403 if (early_read_config_byte(hose,
404 current_bus,
405 pci_devfn,
406 PCI_HEADER_TYPE,
407 &header_type))
408 continue;
409
410 if (!PCI_FUNC(pci_devfn))
411 found_multi = header_type & 0x80;
412
413 early_read_config_word(hose,
414 current_bus,
415 pci_devfn,
416 PCI_VENDOR_ID,
417 &vid);
418
419 if (vid != 0xffff) {
420 early_read_config_dword(hose,
421 current_bus,
422 pci_devfn,
423 PCI_CLASS_REVISION, &pci_class);
424 if ( (pci_class >> 16) == PCI_CLASS_BRIDGE_PCI ) {
425 int iosave, memsave;
426
427 DBG("PCI Autoconfig: Found P2P bridge, device %d\n", PCI_SLOT(pci_devfn));
428 /* Allocate PCI I/O and/or memory space */
429 pciauto_setup_bars(hose,
430 current_bus,
431 pci_devfn,
432 PCI_BASE_ADDRESS_1);
433
434 pciauto_prescan_setup_bridge(hose,
435 current_bus,
436 pci_devfn,
437 sub_bus,
438 &iosave,
439 &memsave);
440 sub_bus = pciauto_bus_scan(hose, sub_bus+1);
441 pciauto_postscan_setup_bridge(hose,
442 current_bus,
443 pci_devfn,
444 sub_bus,
445 &iosave,
446 &memsave);
447 } else if ((pci_class >> 16) == PCI_CLASS_BRIDGE_CARDBUS) {
448 int iosave, memsave;
449
450 DBG("PCI Autoconfig: Found CardBus bridge, device %d function %d\n", PCI_SLOT(pci_devfn), PCI_FUNC(pci_devfn));
451 /* Place CardBus Socket/ExCA registers */
452 pciauto_setup_bars(hose,
453 current_bus,
454 pci_devfn,
455 PCI_BASE_ADDRESS_0);
456
457 pciauto_prescan_setup_cardbus_bridge(hose,
458 current_bus,
459 pci_devfn,
460 sub_bus,
461 &iosave,
462 &memsave);
463 sub_bus = pciauto_bus_scan(hose, sub_bus+1);
464 pciauto_postscan_setup_cardbus_bridge(hose,
465 current_bus,
466 pci_devfn,
467 sub_bus,
468 &iosave,
469 &memsave);
470 } else {
471 if ((pci_class >> 16) == PCI_CLASS_STORAGE_IDE) {
472 unsigned char prg_iface;
473
474 early_read_config_byte(hose,
475 current_bus,
476 pci_devfn,
477 PCI_CLASS_PROG,
478 &prg_iface);
479 if (!(prg_iface & PCIAUTO_IDE_MODE_MASK)) {
480 DBG("PCI Autoconfig: Skipping legacy mode IDE controller\n");
481 continue;
482 }
483 }
484 /* Allocate PCI I/O and/or memory space */
485 pciauto_setup_bars(hose,
486 current_bus,
487 pci_devfn,
488 PCI_BASE_ADDRESS_5);
489
490 /*
491 * Enable some standard settings
492 */
493 early_read_config_dword(hose,
494 current_bus,
495 pci_devfn,
496 PCI_COMMAND,
497 &cmdstat);
498 early_write_config_dword(hose,
499 current_bus,
500 pci_devfn,
501 PCI_COMMAND,
502 cmdstat |
503 PCI_COMMAND_IO |
504 PCI_COMMAND_MEMORY |
505 PCI_COMMAND_MASTER);
506 early_write_config_byte(hose,
507 current_bus,
508 pci_devfn,
509 PCI_LATENCY_TIMER,
510 0x80);
511 }
512 }
513 }
514 return sub_bus;
515}