xref: /freebsd/sys/dev/pci/pci_subr.c (revision 3494f7c019fc6558a99f63b7f647373b89bcde92)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 /*
32  * Support APIs for Host to PCI bridge drivers and drivers that
33  * provide PCI domains.
34  */
35 
36 #include <sys/param.h>
37 #include <sys/bus.h>
38 #include <sys/malloc.h>
39 #include <sys/rman.h>
40 #include <sys/systm.h>
41 
42 #include <dev/pci/pcireg.h>
43 #include <dev/pci/pcivar.h>
44 #include <dev/pci/pcib_private.h>
45 
46 /*
47  * Try to read the bus number of a host-PCI bridge using appropriate config
48  * registers.
49  */
50 int
51 host_pcib_get_busno(pci_read_config_fn read_config, int bus, int slot, int func,
52     uint8_t *busnum)
53 {
54 	uint32_t id;
55 
56 	id = read_config(0, bus, slot, func, PCIR_DEVVENDOR, 4);
57 	if (id == 0xffffffff)
58 		return (0);
59 
60 	switch (id) {
61 	case 0x12258086:
62 		/* Intel 824?? */
63 		/* XXX This is a guess */
64 		/* *busnum = read_config(0, bus, slot, func, 0x41, 1); */
65 		*busnum = bus;
66 		break;
67 	case 0x84c48086:
68 		/* Intel 82454KX/GX (Orion) */
69 		*busnum = read_config(0, bus, slot, func, 0x4a, 1);
70 		break;
71 	case 0x84ca8086:
72 		/*
73 		 * For the 450nx chipset, there is a whole bundle of
74 		 * things pretending to be host bridges. The MIOC will
75 		 * be seen first and isn't really a pci bridge (the
76 		 * actual buses are attached to the PXB's). We need to
77 		 * read the registers of the MIOC to figure out the
78 		 * bus numbers for the PXB channels.
79 		 *
80 		 * Since the MIOC doesn't have a pci bus attached, we
81 		 * pretend it wasn't there.
82 		 */
83 		return (0);
84 	case 0x84cb8086:
85 		switch (slot) {
86 		case 0x12:
87 			/* Intel 82454NX PXB#0, Bus#A */
88 			*busnum = read_config(0, bus, 0x10, func, 0xd0, 1);
89 			break;
90 		case 0x13:
91 			/* Intel 82454NX PXB#0, Bus#B */
92 			*busnum = read_config(0, bus, 0x10, func, 0xd1, 1) + 1;
93 			break;
94 		case 0x14:
95 			/* Intel 82454NX PXB#1, Bus#A */
96 			*busnum = read_config(0, bus, 0x10, func, 0xd3, 1);
97 			break;
98 		case 0x15:
99 			/* Intel 82454NX PXB#1, Bus#B */
100 			*busnum = read_config(0, bus, 0x10, func, 0xd4, 1) + 1;
101 			break;
102 		}
103 		break;
104 
105 		/* ServerWorks -- vendor 0x1166 */
106 	case 0x00051166:
107 	case 0x00061166:
108 	case 0x00081166:
109 	case 0x00091166:
110 	case 0x00101166:
111 	case 0x00111166:
112 	case 0x00171166:
113 	case 0x01011166:
114 	case 0x010f1014:
115 	case 0x01101166:
116 	case 0x02011166:
117 	case 0x02251166:
118 	case 0x03021014:
119 		*busnum = read_config(0, bus, slot, func, 0x44, 1);
120 		break;
121 
122 		/* Compaq/HP -- vendor 0x0e11 */
123 	case 0x60100e11:
124 		*busnum = read_config(0, bus, slot, func, 0xc8, 1);
125 		break;
126 	default:
127 		/* Don't know how to read bus number. */
128 		return 0;
129 	}
130 
131 	return 1;
132 }
133 
134 #ifdef NEW_PCIB
135 /*
136  * Return a pointer to a pretty name for a PCI device.  If the device
137  * has a driver attached, the device's name is used, otherwise a name
138  * is generated from the device's PCI address.
139  */
140 const char *
141 pcib_child_name(device_t child)
142 {
143 	static char buf[64];
144 
145 	if (device_get_nameunit(child) != NULL)
146 		return (device_get_nameunit(child));
147 	snprintf(buf, sizeof(buf), "pci%d:%d:%d:%d", pci_get_domain(child),
148 	    pci_get_bus(child), pci_get_slot(child), pci_get_function(child));
149 	return (buf);
150 }
151 
152 /*
153  * Some Host-PCI bridge drivers know which resource ranges they can
154  * decode and should only allocate subranges to child PCI devices.
155  * This API provides a way to manage this.  The bridge driver should
156  * initialize this structure during attach and call
157  * pcib_host_res_decodes() on each resource range it decodes.  It can
158  * then use pcib_host_res_alloc() and pcib_host_res_adjust() as helper
159  * routines for BUS_ALLOC_RESOURCE() and BUS_ADJUST_RESOURCE().  This
160  * API assumes that resources for any decoded ranges can be safely
161  * allocated from the parent via bus_generic_alloc_resource().
162  */
163 int
164 pcib_host_res_init(device_t pcib, struct pcib_host_resources *hr)
165 {
166 
167 	hr->hr_pcib = pcib;
168 	resource_list_init(&hr->hr_rl);
169 	return (0);
170 }
171 
172 int
173 pcib_host_res_free(device_t pcib, struct pcib_host_resources *hr)
174 {
175 
176 	resource_list_free(&hr->hr_rl);
177 	return (0);
178 }
179 
180 int
181 pcib_host_res_decodes(struct pcib_host_resources *hr, int type, rman_res_t start,
182     rman_res_t end, u_int flags)
183 {
184 	struct resource_list_entry *rle;
185 	int rid;
186 
187 	if (bootverbose)
188 		device_printf(hr->hr_pcib, "decoding %d %srange %#jx-%#jx\n",
189 		    type, flags & RF_PREFETCHABLE ? "prefetchable ": "", start,
190 		    end);
191 	rid = resource_list_add_next(&hr->hr_rl, type, start, end,
192 	    end - start + 1);
193 	if (flags & RF_PREFETCHABLE) {
194 		KASSERT(type == SYS_RES_MEMORY,
195 		    ("only memory is prefetchable"));
196 		rle = resource_list_find(&hr->hr_rl, type, rid);
197 		rle->flags = RLE_PREFETCH;
198 	}
199 	return (0);
200 }
201 
202 struct resource *
203 pcib_host_res_alloc(struct pcib_host_resources *hr, device_t dev, int type,
204     int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
205 {
206 	struct resource_list_entry *rle;
207 	struct resource *r;
208 	rman_res_t new_start, new_end;
209 
210 	if (flags & RF_PREFETCHABLE)
211 		KASSERT(type == SYS_RES_MEMORY,
212 		    ("only memory is prefetchable"));
213 
214 	rle = resource_list_find(&hr->hr_rl, type, 0);
215 	if (rle == NULL) {
216 		/*
217 		 * No decoding ranges for this resource type, just pass
218 		 * the request up to the parent.
219 		 */
220 		return (bus_generic_alloc_resource(hr->hr_pcib, dev, type, rid,
221 		    start, end, count, flags));
222 	}
223 
224 restart:
225 	/* Try to allocate from each decoded range. */
226 	for (; rle != NULL; rle = STAILQ_NEXT(rle, link)) {
227 		if (rle->type != type)
228 			continue;
229 		if (((flags & RF_PREFETCHABLE) != 0) !=
230 		    ((rle->flags & RLE_PREFETCH) != 0))
231 			continue;
232 		new_start = ummax(start, rle->start);
233 		new_end = ummin(end, rle->end);
234 		if (new_start > new_end ||
235 		    new_start + count - 1 > new_end ||
236 		    new_start + count < new_start)
237 			continue;
238 		r = bus_generic_alloc_resource(hr->hr_pcib, dev, type, rid,
239 		    new_start, new_end, count, flags);
240 		if (r != NULL) {
241 			if (bootverbose)
242 				device_printf(hr->hr_pcib,
243 			    "allocated type %d (%#jx-%#jx) for rid %x of %s\n",
244 				    type, rman_get_start(r), rman_get_end(r),
245 				    *rid, pcib_child_name(dev));
246 			return (r);
247 		}
248 	}
249 
250 	/*
251 	 * If we failed to find a prefetch range for a memory
252 	 * resource, try again without prefetch.
253 	 */
254 	if (flags & RF_PREFETCHABLE) {
255 		flags &= ~RF_PREFETCHABLE;
256 		rle = resource_list_find(&hr->hr_rl, type, 0);
257 		goto restart;
258 	}
259 	return (NULL);
260 }
261 
262 int
263 pcib_host_res_adjust(struct pcib_host_resources *hr, device_t dev, int type,
264     struct resource *r, rman_res_t start, rman_res_t end)
265 {
266 	struct resource_list_entry *rle;
267 
268 	rle = resource_list_find(&hr->hr_rl, type, 0);
269 	if (rle == NULL) {
270 		/*
271 		 * No decoding ranges for this resource type, just pass
272 		 * the request up to the parent.
273 		 */
274 		return (bus_generic_adjust_resource(hr->hr_pcib, dev, type, r,
275 		    start, end));
276 	}
277 
278 	/* Only allow adjustments that stay within a decoded range. */
279 	for (; rle != NULL; rle = STAILQ_NEXT(rle, link)) {
280 		if (rle->start <= start && rle->end >= end)
281 			return (bus_generic_adjust_resource(hr->hr_pcib, dev,
282 			    type, r, start, end));
283 	}
284 	return (ERANGE);
285 }
286 
287 #ifdef PCI_RES_BUS
288 struct pci_domain {
289 	int	pd_domain;
290 	struct rman pd_bus_rman;
291 	TAILQ_ENTRY(pci_domain) pd_link;
292 };
293 
294 static TAILQ_HEAD(, pci_domain) domains = TAILQ_HEAD_INITIALIZER(domains);
295 
296 /*
297  * Each PCI domain maintains its own resource manager for PCI bus
298  * numbers in that domain.  Domain objects are created on first use.
299  * Host to PCI bridge drivers and PCI-PCI bridge drivers should
300  * allocate their bus ranges from their domain.
301  */
302 static struct pci_domain *
303 pci_find_domain(int domain)
304 {
305 	struct pci_domain *d;
306 	char buf[64];
307 	int error;
308 
309 	TAILQ_FOREACH(d, &domains, pd_link) {
310 		if (d->pd_domain == domain)
311 			return (d);
312 	}
313 
314 	snprintf(buf, sizeof(buf), "PCI domain %d bus numbers", domain);
315 	d = malloc(sizeof(*d) + strlen(buf) + 1, M_DEVBUF, M_WAITOK | M_ZERO);
316 	d->pd_domain = domain;
317 	d->pd_bus_rman.rm_start = 0;
318 	d->pd_bus_rman.rm_end = PCI_BUSMAX;
319 	d->pd_bus_rman.rm_type = RMAN_ARRAY;
320 	strcpy((char *)(d + 1), buf);
321 	d->pd_bus_rman.rm_descr = (char *)(d + 1);
322 	error = rman_init(&d->pd_bus_rman);
323 	if (error == 0)
324 		error = rman_manage_region(&d->pd_bus_rman, 0, PCI_BUSMAX);
325 	if (error)
326 		panic("Failed to initialize PCI domain %d rman", domain);
327 	TAILQ_INSERT_TAIL(&domains, d, pd_link);
328 	return (d);
329 }
330 
331 struct resource *
332 pci_domain_alloc_bus(int domain, device_t dev, int *rid, rman_res_t start,
333     rman_res_t end, rman_res_t count, u_int flags)
334 {
335 	struct pci_domain *d;
336 	struct resource *res;
337 
338 	if (domain < 0 || domain > PCI_DOMAINMAX)
339 		return (NULL);
340 	d = pci_find_domain(domain);
341 	res = rman_reserve_resource(&d->pd_bus_rman, start, end, count, flags,
342 	    dev);
343 	if (res == NULL)
344 		return (NULL);
345 
346 	rman_set_rid(res, *rid);
347 	return (res);
348 }
349 
350 int
351 pci_domain_adjust_bus(int domain, device_t dev, struct resource *r,
352     rman_res_t start, rman_res_t end)
353 {
354 #ifdef INVARIANTS
355 	struct pci_domain *d;
356 #endif
357 
358 	if (domain < 0 || domain > PCI_DOMAINMAX)
359 		return (EINVAL);
360 #ifdef INVARIANTS
361 	d = pci_find_domain(domain);
362 	KASSERT(rman_is_region_manager(r, &d->pd_bus_rman), ("bad resource"));
363 #endif
364 	return (rman_adjust_resource(r, start, end));
365 }
366 
367 int
368 pci_domain_release_bus(int domain, device_t dev, int rid, struct resource *r)
369 {
370 #ifdef INVARIANTS
371 	struct pci_domain *d;
372 #endif
373 
374 	if (domain < 0 || domain > PCI_DOMAINMAX)
375 		return (EINVAL);
376 #ifdef INVARIANTS
377 	d = pci_find_domain(domain);
378 	KASSERT(rman_is_region_manager(r, &d->pd_bus_rman), ("bad resource"));
379 #endif
380 	return (rman_release_resource(r));
381 }
382 #endif /* PCI_RES_BUS */
383 
384 #endif /* NEW_PCIB */
385