xref: /freebsd/sys/dev/pci/pci_subr.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2011 Hudson River Trading LLC
5  * Written by: John H. Baldwin <jhb@FreeBSD.org>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 /*
34  * Support APIs for Host to PCI bridge drivers and drivers that
35  * provide PCI domains.
36  */
37 
38 #include <sys/param.h>
39 #include <sys/bus.h>
40 #include <sys/malloc.h>
41 #include <sys/rman.h>
42 #include <sys/systm.h>
43 
44 #include <dev/pci/pcireg.h>
45 #include <dev/pci/pcivar.h>
46 #include <dev/pci/pcib_private.h>
47 
48 /*
49  * Try to read the bus number of a host-PCI bridge using appropriate config
50  * registers.
51  */
52 int
53 host_pcib_get_busno(pci_read_config_fn read_config, int bus, int slot, int func,
54     uint8_t *busnum)
55 {
56 	uint32_t id;
57 
58 	id = read_config(bus, slot, func, PCIR_DEVVENDOR, 4);
59 	if (id == 0xffffffff)
60 		return (0);
61 
62 	switch (id) {
63 	case 0x12258086:
64 		/* Intel 824?? */
65 		/* XXX This is a guess */
66 		/* *busnum = read_config(bus, slot, func, 0x41, 1); */
67 		*busnum = bus;
68 		break;
69 	case 0x84c48086:
70 		/* Intel 82454KX/GX (Orion) */
71 		*busnum = read_config(bus, slot, func, 0x4a, 1);
72 		break;
73 	case 0x84ca8086:
74 		/*
75 		 * For the 450nx chipset, there is a whole bundle of
76 		 * things pretending to be host bridges. The MIOC will
77 		 * be seen first and isn't really a pci bridge (the
78 		 * actual buses are attached to the PXB's). We need to
79 		 * read the registers of the MIOC to figure out the
80 		 * bus numbers for the PXB channels.
81 		 *
82 		 * Since the MIOC doesn't have a pci bus attached, we
83 		 * pretend it wasn't there.
84 		 */
85 		return (0);
86 	case 0x84cb8086:
87 		switch (slot) {
88 		case 0x12:
89 			/* Intel 82454NX PXB#0, Bus#A */
90 			*busnum = read_config(bus, 0x10, func, 0xd0, 1);
91 			break;
92 		case 0x13:
93 			/* Intel 82454NX PXB#0, Bus#B */
94 			*busnum = read_config(bus, 0x10, func, 0xd1, 1) + 1;
95 			break;
96 		case 0x14:
97 			/* Intel 82454NX PXB#1, Bus#A */
98 			*busnum = read_config(bus, 0x10, func, 0xd3, 1);
99 			break;
100 		case 0x15:
101 			/* Intel 82454NX PXB#1, Bus#B */
102 			*busnum = read_config(bus, 0x10, func, 0xd4, 1) + 1;
103 			break;
104 		}
105 		break;
106 
107 		/* ServerWorks -- vendor 0x1166 */
108 	case 0x00051166:
109 	case 0x00061166:
110 	case 0x00081166:
111 	case 0x00091166:
112 	case 0x00101166:
113 	case 0x00111166:
114 	case 0x00171166:
115 	case 0x01011166:
116 	case 0x010f1014:
117 	case 0x01101166:
118 	case 0x02011166:
119 	case 0x02251166:
120 	case 0x03021014:
121 		*busnum = read_config(bus, slot, func, 0x44, 1);
122 		break;
123 
124 		/* Compaq/HP -- vendor 0x0e11 */
125 	case 0x60100e11:
126 		*busnum = read_config(bus, slot, func, 0xc8, 1);
127 		break;
128 	default:
129 		/* Don't know how to read bus number. */
130 		return 0;
131 	}
132 
133 	return 1;
134 }
135 
136 #ifdef NEW_PCIB
137 /*
138  * Return a pointer to a pretty name for a PCI device.  If the device
139  * has a driver attached, the device's name is used, otherwise a name
140  * is generated from the device's PCI address.
141  */
142 const char *
143 pcib_child_name(device_t child)
144 {
145 	static char buf[64];
146 
147 	if (device_get_nameunit(child) != NULL)
148 		return (device_get_nameunit(child));
149 	snprintf(buf, sizeof(buf), "pci%d:%d:%d:%d", pci_get_domain(child),
150 	    pci_get_bus(child), pci_get_slot(child), pci_get_function(child));
151 	return (buf);
152 }
153 
154 /*
155  * Some Host-PCI bridge drivers know which resource ranges they can
156  * decode and should only allocate subranges to child PCI devices.
157  * This API provides a way to manage this.  The bridge driver should
158  * initialize this structure during attach and call
159  * pcib_host_res_decodes() on each resource range it decodes.  It can
160  * then use pcib_host_res_alloc() and pcib_host_res_adjust() as helper
161  * routines for BUS_ALLOC_RESOURCE() and BUS_ADJUST_RESOURCE().  This
162  * API assumes that resources for any decoded ranges can be safely
163  * allocated from the parent via bus_generic_alloc_resource().
164  */
165 int
166 pcib_host_res_init(device_t pcib, struct pcib_host_resources *hr)
167 {
168 
169 	hr->hr_pcib = pcib;
170 	resource_list_init(&hr->hr_rl);
171 	return (0);
172 }
173 
174 int
175 pcib_host_res_free(device_t pcib, struct pcib_host_resources *hr)
176 {
177 
178 	resource_list_free(&hr->hr_rl);
179 	return (0);
180 }
181 
182 int
183 pcib_host_res_decodes(struct pcib_host_resources *hr, int type, rman_res_t start,
184     rman_res_t end, u_int flags)
185 {
186 	struct resource_list_entry *rle;
187 	int rid;
188 
189 	if (bootverbose)
190 		device_printf(hr->hr_pcib, "decoding %d %srange %#jx-%#jx\n",
191 		    type, flags & RF_PREFETCHABLE ? "prefetchable ": "", start,
192 		    end);
193 	rid = resource_list_add_next(&hr->hr_rl, type, start, end,
194 	    end - start + 1);
195 	if (flags & RF_PREFETCHABLE) {
196 		KASSERT(type == SYS_RES_MEMORY,
197 		    ("only memory is prefetchable"));
198 		rle = resource_list_find(&hr->hr_rl, type, rid);
199 		rle->flags = RLE_PREFETCH;
200 	}
201 	return (0);
202 }
203 
204 struct resource *
205 pcib_host_res_alloc(struct pcib_host_resources *hr, device_t dev, int type,
206     int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
207 {
208 	struct resource_list_entry *rle;
209 	struct resource *r;
210 	rman_res_t new_start, new_end;
211 
212 	if (flags & RF_PREFETCHABLE)
213 		KASSERT(type == SYS_RES_MEMORY,
214 		    ("only memory is prefetchable"));
215 
216 	rle = resource_list_find(&hr->hr_rl, type, 0);
217 	if (rle == NULL) {
218 		/*
219 		 * No decoding ranges for this resource type, just pass
220 		 * the request up to the parent.
221 		 */
222 		return (bus_generic_alloc_resource(hr->hr_pcib, dev, type, rid,
223 		    start, end, count, flags));
224 	}
225 
226 restart:
227 	/* Try to allocate from each decoded range. */
228 	for (; rle != NULL; rle = STAILQ_NEXT(rle, link)) {
229 		if (rle->type != type)
230 			continue;
231 		if (((flags & RF_PREFETCHABLE) != 0) !=
232 		    ((rle->flags & RLE_PREFETCH) != 0))
233 			continue;
234 		new_start = ummax(start, rle->start);
235 		new_end = ummin(end, rle->end);
236 		if (new_start > new_end ||
237 		    new_start + count - 1 > new_end ||
238 		    new_start + count < new_start)
239 			continue;
240 		r = bus_generic_alloc_resource(hr->hr_pcib, dev, type, rid,
241 		    new_start, new_end, count, flags);
242 		if (r != NULL) {
243 			if (bootverbose)
244 				device_printf(hr->hr_pcib,
245 			    "allocated type %d (%#jx-%#jx) for rid %x of %s\n",
246 				    type, rman_get_start(r), rman_get_end(r),
247 				    *rid, pcib_child_name(dev));
248 			return (r);
249 		}
250 	}
251 
252 	/*
253 	 * If we failed to find a prefetch range for a memory
254 	 * resource, try again without prefetch.
255 	 */
256 	if (flags & RF_PREFETCHABLE) {
257 		flags &= ~RF_PREFETCHABLE;
258 		rle = resource_list_find(&hr->hr_rl, type, 0);
259 		goto restart;
260 	}
261 	return (NULL);
262 }
263 
264 int
265 pcib_host_res_adjust(struct pcib_host_resources *hr, device_t dev, int type,
266     struct resource *r, rman_res_t start, rman_res_t end)
267 {
268 	struct resource_list_entry *rle;
269 
270 	rle = resource_list_find(&hr->hr_rl, type, 0);
271 	if (rle == NULL) {
272 		/*
273 		 * No decoding ranges for this resource type, just pass
274 		 * the request up to the parent.
275 		 */
276 		return (bus_generic_adjust_resource(hr->hr_pcib, dev, type, r,
277 		    start, end));
278 	}
279 
280 	/* Only allow adjustments that stay within a decoded range. */
281 	for (; rle != NULL; rle = STAILQ_NEXT(rle, link)) {
282 		if (rle->start <= start && rle->end >= end)
283 			return (bus_generic_adjust_resource(hr->hr_pcib, dev,
284 			    type, r, start, end));
285 	}
286 	return (ERANGE);
287 }
288 
289 #ifdef PCI_RES_BUS
290 struct pci_domain {
291 	int	pd_domain;
292 	struct rman pd_bus_rman;
293 	TAILQ_ENTRY(pci_domain) pd_link;
294 };
295 
296 static TAILQ_HEAD(, pci_domain) domains = TAILQ_HEAD_INITIALIZER(domains);
297 
298 /*
299  * Each PCI domain maintains its own resource manager for PCI bus
300  * numbers in that domain.  Domain objects are created on first use.
301  * Host to PCI bridge drivers and PCI-PCI bridge drivers should
302  * allocate their bus ranges from their domain.
303  */
304 static struct pci_domain *
305 pci_find_domain(int domain)
306 {
307 	struct pci_domain *d;
308 	char buf[64];
309 	int error;
310 
311 	TAILQ_FOREACH(d, &domains, pd_link) {
312 		if (d->pd_domain == domain)
313 			return (d);
314 	}
315 
316 	snprintf(buf, sizeof(buf), "PCI domain %d bus numbers", domain);
317 	d = malloc(sizeof(*d) + strlen(buf) + 1, M_DEVBUF, M_WAITOK | M_ZERO);
318 	d->pd_domain = domain;
319 	d->pd_bus_rman.rm_start = 0;
320 	d->pd_bus_rman.rm_end = PCI_BUSMAX;
321 	d->pd_bus_rman.rm_type = RMAN_ARRAY;
322 	strcpy((char *)(d + 1), buf);
323 	d->pd_bus_rman.rm_descr = (char *)(d + 1);
324 	error = rman_init(&d->pd_bus_rman);
325 	if (error == 0)
326 		error = rman_manage_region(&d->pd_bus_rman, 0, PCI_BUSMAX);
327 	if (error)
328 		panic("Failed to initialize PCI domain %d rman", domain);
329 	TAILQ_INSERT_TAIL(&domains, d, pd_link);
330 	return (d);
331 }
332 
333 struct resource *
334 pci_domain_alloc_bus(int domain, device_t dev, int *rid, rman_res_t start,
335     rman_res_t end, rman_res_t count, u_int flags)
336 {
337 	struct pci_domain *d;
338 	struct resource *res;
339 
340 	if (domain < 0 || domain > PCI_DOMAINMAX)
341 		return (NULL);
342 	d = pci_find_domain(domain);
343 	res = rman_reserve_resource(&d->pd_bus_rman, start, end, count, flags,
344 	    dev);
345 	if (res == NULL)
346 		return (NULL);
347 
348 	rman_set_rid(res, *rid);
349 	return (res);
350 }
351 
352 int
353 pci_domain_adjust_bus(int domain, device_t dev, struct resource *r,
354     rman_res_t start, rman_res_t end)
355 {
356 #ifdef INVARIANTS
357 	struct pci_domain *d;
358 #endif
359 
360 	if (domain < 0 || domain > PCI_DOMAINMAX)
361 		return (EINVAL);
362 #ifdef INVARIANTS
363 	d = pci_find_domain(domain);
364 	KASSERT(rman_is_region_manager(r, &d->pd_bus_rman), ("bad resource"));
365 #endif
366 	return (rman_adjust_resource(r, start, end));
367 }
368 
369 int
370 pci_domain_release_bus(int domain, device_t dev, int rid, struct resource *r)
371 {
372 #ifdef INVARIANTS
373 	struct pci_domain *d;
374 #endif
375 
376 	if (domain < 0 || domain > PCI_DOMAINMAX)
377 		return (EINVAL);
378 #ifdef INVARIANTS
379 	d = pci_find_domain(domain);
380 	KASSERT(rman_is_region_manager(r, &d->pd_bus_rman), ("bad resource"));
381 #endif
382 	return (rman_release_resource(r));
383 }
384 #endif /* PCI_RES_BUS */
385 
386 #endif /* NEW_PCIB */
387