xref: /freebsd/sys/i386/pci/pci_cfgreg.c (revision bec35b9a5f0cdb233b0601c507114d11a1093126)
1 /*
2  * Copyright (c) 1997, Stefan Esser <se@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice unmodified, this list of conditions, and the following
10  *    disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  *
28  */
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/kernel.h>
34 
35 #include <pci/pcivar.h>
36 #include <pci/pcireg.h>
37 #include <i386/isa/pcibus.h>
38 
39 #include <machine/segments.h>
40 #include <machine/pc/bios.h>
41 
42 static int cfgmech;
43 static int devmax;
44 static int usebios;
45 
46 static int	pcibios_cfgread(pcicfgregs *cfg, int reg, int bytes);
47 static void	pcibios_cfgwrite(pcicfgregs *cfg, int reg, int data, int bytes);
48 static int	pcibios_cfgopen(void);
49 static int	pcireg_cfgread(pcicfgregs *cfg, int reg, int bytes);
50 static void	pcireg_cfgwrite(pcicfgregs *cfg, int reg, int data, int bytes);
51 static int	pcireg_cfgopen(void);
52 
53 /* read configuration space register */
54 
55 int
56 pci_cfgread(pcicfgregs *cfg, int reg, int bytes)
57 {
58 	return(usebios ?
59 	       pcibios_cfgread(cfg, reg, bytes) :
60 	       pcireg_cfgread(cfg, reg, bytes));
61 }
62 
63 /* write configuration space register */
64 
65 void
66 pci_cfgwrite(pcicfgregs *cfg, int reg, int data, int bytes)
67 {
68 	return(usebios ?
69 	       pcibios_cfgwrite(cfg, reg, data, bytes) :
70 	       pcireg_cfgwrite(cfg, reg, data, bytes));
71 }
72 
73 /* initialise access to PCI configuration space */
74 static int
75 pci_cfgopen(void)
76 {
77 	if (pcibios_cfgopen() != 0) {
78 		usebios = 1;
79 	} else if (pcireg_cfgopen() != 0) {
80 		usebios = 0;
81 	} else {
82 		return(0);
83 	}
84 	return(1);
85 }
86 
87 /* config space access using BIOS functions */
88 
89 static int
90 pcibios_cfgread(pcicfgregs *cfg, int reg, int bytes)
91 {
92 	struct bios_regs args;
93 	u_int mask;
94 
95 	switch(bytes) {
96 	case 1:
97 		args.eax = PCIBIOS_READ_CONFIG_BYTE;
98 		mask = 0xff;
99 		break;
100 	case 2:
101 		args.eax = PCIBIOS_READ_CONFIG_WORD;
102 		mask = 0xffff;
103 		break;
104 	case 4:
105 		args.eax = PCIBIOS_READ_CONFIG_DWORD;
106 		mask = 0xffffffff;
107 		break;
108 	default:
109 		return(-1);
110 	}
111 	args.ebx = (cfg->bus << 8) | (cfg->slot << 3) | (cfg->func);
112 	args.edi = reg;
113 	bios32(&args, PCIbios.ventry, GSEL(GCODE_SEL, SEL_KPL));
114 	/* check call results? */
115 	return(args.ecx & mask);
116 }
117 
118 static void
119 pcibios_cfgwrite(pcicfgregs *cfg, int reg, int data, int bytes)
120 {
121 	struct bios_regs args;
122 
123 	switch(bytes) {
124 	case 1:
125 		args.eax = PCIBIOS_WRITE_CONFIG_BYTE;
126 		break;
127 	case 2:
128 		args.eax = PCIBIOS_WRITE_CONFIG_WORD;
129 		break;
130 	case 4:
131 		args.eax = PCIBIOS_WRITE_CONFIG_DWORD;
132 		break;
133 	default:
134 		return;
135 	}
136 	args.ebx = (cfg->bus << 8) | (cfg->slot << 3) | (cfg->func);
137 	args.ecx = data;
138 	args.edi = reg;
139 	bios32(&args, PCIbios.ventry, GSEL(GCODE_SEL, SEL_KPL));
140 }
141 
142 /* determine whether there is a PCI BIOS present */
143 
144 static int
145 pcibios_cfgopen(void)
146 {
147 	/* check for a found entrypoint */
148 	return(PCIbios.entry != 0);
149 }
150 
151 /* configuration space access using direct register operations */
152 
153 /* enable configuration space accesses and return data port address */
154 
155 static int
156 pci_cfgenable(unsigned bus, unsigned slot, unsigned func, int reg, int bytes)
157 {
158 	int dataport = 0;
159 
160 	if (bus <= PCI_BUSMAX
161 	    && slot < devmax
162 	    && func <= PCI_FUNCMAX
163 	    && reg <= PCI_REGMAX
164 	    && bytes != 3
165 	    && (unsigned) bytes <= 4
166 	    && (reg & (bytes -1)) == 0) {
167 		switch (cfgmech) {
168 		case 1:
169 			outl(CONF1_ADDR_PORT, (1 << 31)
170 			     | (bus << 16) | (slot << 11)
171 			     | (func << 8) | (reg & ~0x03));
172 			dataport = CONF1_DATA_PORT + (reg & 0x03);
173 			break;
174 		case 2:
175 			outb(CONF2_ENABLE_PORT, 0xf0 | (func << 1));
176 			outb(CONF2_FORWARD_PORT, bus);
177 			dataport = 0xc000 | (slot << 8) | reg;
178 			break;
179 		}
180 	}
181 	return (dataport);
182 }
183 
184 /* disable configuration space accesses */
185 
186 static void
187 pci_cfgdisable(void)
188 {
189 	switch (cfgmech) {
190 	case 1:
191 		outl(CONF1_ADDR_PORT, 0);
192 		break;
193 	case 2:
194 		outb(CONF2_ENABLE_PORT, 0);
195 		outb(CONF2_FORWARD_PORT, 0);
196 		break;
197 	}
198 }
199 
200 static int
201 pcireg_cfgread(pcicfgregs *cfg, int reg, int bytes)
202 {
203 	int data = -1;
204 	int port;
205 
206 	port = pci_cfgenable(cfg->bus, cfg->slot, cfg->func, reg, bytes);
207 
208 	if (port != 0) {
209 		switch (bytes) {
210 		case 1:
211 			data = inb(port);
212 			break;
213 		case 2:
214 			data = inw(port);
215 			break;
216 		case 4:
217 			data = inl(port);
218 			break;
219 		}
220 		pci_cfgdisable();
221 	}
222 	return (data);
223 }
224 
225 static void
226 pcireg_cfgwrite(pcicfgregs *cfg, int reg, int data, int bytes)
227 {
228 	int port;
229 
230 	port = pci_cfgenable(cfg->bus, cfg->slot, cfg->func, reg, bytes);
231 	if (port != 0) {
232 		switch (bytes) {
233 		case 1:
234 			outb(port, data);
235 			break;
236 		case 2:
237 			outw(port, data);
238 			break;
239 		case 4:
240 			outl(port, data);
241 			break;
242 		}
243 		pci_cfgdisable();
244 	}
245 }
246 
247 /* check whether the configuration mechanism has been correct identified */
248 
249 static int
250 pci_cfgcheck(int maxdev)
251 {
252 	u_char device;
253 
254 	if (bootverbose)
255 		printf("pci_cfgcheck:\tdevice ");
256 
257 	for (device = 0; device < maxdev; device++) {
258 		unsigned id, class, header;
259 		if (bootverbose)
260 			printf("%d ", device);
261 
262 		id = inl(pci_cfgenable(0, device, 0, 0, 4));
263 		if (id == 0 || id == -1)
264 			continue;
265 
266 		class = inl(pci_cfgenable(0, device, 0, 8, 4)) >> 8;
267 		if (bootverbose)
268 			printf("[class=%06x] ", class);
269 		if (class == 0 || (class & 0xf870ff) != 0)
270 			continue;
271 
272 		header = inb(pci_cfgenable(0, device, 0, 14, 1));
273 		if (bootverbose)
274 			printf("[hdr=%02x] ", header);
275 		if ((header & 0x7e) != 0)
276 			continue;
277 
278 		if (bootverbose)
279 			printf("is there (id=%08x)\n", id);
280 
281 		pci_cfgdisable();
282 		return (1);
283 	}
284 	if (bootverbose)
285 		printf("-- nothing found\n");
286 
287 	pci_cfgdisable();
288 	return (0);
289 }
290 
291 static int
292 pcireg_cfgopen(void)
293 {
294 	unsigned long mode1res,oldval1;
295 	unsigned char mode2res,oldval2;
296 
297 	oldval1 = inl(CONF1_ADDR_PORT);
298 
299 	if (bootverbose) {
300 		printf("pci_open(1):\tmode 1 addr port (0x0cf8) is 0x%08lx\n",
301 		       oldval1);
302 	}
303 
304 	if ((oldval1 & CONF1_ENABLE_MSK) == 0) {
305 
306 		cfgmech = 1;
307 		devmax = 32;
308 
309 		outl(CONF1_ADDR_PORT, CONF1_ENABLE_CHK);
310 		outb(CONF1_ADDR_PORT +3, 0);
311 		mode1res = inl(CONF1_ADDR_PORT);
312 		outl(CONF1_ADDR_PORT, oldval1);
313 
314 		if (bootverbose)
315 			printf("pci_open(1a):\tmode1res=0x%08lx (0x%08lx)\n",
316 			       mode1res, CONF1_ENABLE_CHK);
317 
318 		if (mode1res) {
319 			if (pci_cfgcheck(32))
320 				return (cfgmech);
321 		}
322 
323 		outl(CONF1_ADDR_PORT, CONF1_ENABLE_CHK1);
324 		mode1res = inl(CONF1_ADDR_PORT);
325 		outl(CONF1_ADDR_PORT, oldval1);
326 
327 		if (bootverbose)
328 			printf("pci_open(1b):\tmode1res=0x%08lx (0x%08lx)\n",
329 			       mode1res, CONF1_ENABLE_CHK1);
330 
331 		if ((mode1res & CONF1_ENABLE_MSK1) == CONF1_ENABLE_RES1) {
332 			if (pci_cfgcheck(32))
333 				return (cfgmech);
334 		}
335 	}
336 
337 	oldval2 = inb(CONF2_ENABLE_PORT);
338 
339 	if (bootverbose) {
340 		printf("pci_open(2):\tmode 2 enable port (0x0cf8) is 0x%02x\n",
341 		       oldval2);
342 	}
343 
344 	if ((oldval2 & 0xf0) == 0) {
345 
346 		cfgmech = 2;
347 		devmax = 16;
348 
349 		outb(CONF2_ENABLE_PORT, CONF2_ENABLE_CHK);
350 		mode2res = inb(CONF2_ENABLE_PORT);
351 		outb(CONF2_ENABLE_PORT, oldval2);
352 
353 		if (bootverbose)
354 			printf("pci_open(2a):\tmode2res=0x%02x (0x%02x)\n",
355 			       mode2res, CONF2_ENABLE_CHK);
356 
357 		if (mode2res == CONF2_ENABLE_RES) {
358 			if (bootverbose)
359 				printf("pci_open(2a):\tnow trying mechanism 2\n");
360 
361 			if (pci_cfgcheck(16))
362 				return (cfgmech);
363 		}
364 	}
365 
366 	cfgmech = 0;
367 	devmax = 0;
368 	return (cfgmech);
369 }
370 
371 static devclass_t	pcib_devclass;
372 
373 static const char *
374 nexus_pcib_is_host_bridge(pcicfgregs *cfg,
375 			  u_int32_t id, u_int8_t class, u_int8_t subclass,
376 			  u_int8_t *busnum)
377 {
378 	const char *s = NULL;
379 	static u_int8_t pxb[4];	/* hack for 450nx */
380 
381 	*busnum = 0;
382 
383 	switch (id) {
384 	case 0x12258086:
385 		s = "Intel 824?? host to PCI bridge";
386 		/* XXX This is a guess */
387 		/* *busnum = pci_cfgread(cfg, 0x41, 1); */
388 		*busnum = cfg->bus;
389 		break;
390 	case 0x71208086:
391 		s = "Intel 82810 (i810 GMCH) Host To Hub bridge";
392 		break;
393 	case 0x71228086:
394 		s = "Intel 82810-DC100 (i810-DC100 GMCH) Host To Hub bridge";
395 		break;
396 	case 0x71248086:
397 		s = "Intel 82810E (i810E GMCH) Host To Hub bridge";
398 		break;
399 	case 0x71808086:
400 		s = "Intel 82443LX (440 LX) host to PCI bridge";
401 		break;
402 	case 0x71908086:
403 		s = "Intel 82443BX (440 BX) host to PCI bridge";
404 		break;
405 	case 0x71928086:
406 		s = "Intel 82443BX host to PCI bridge (AGP disabled)";
407 		break;
408 	case 0x71a08086:
409 		s = "Intel 82443GX host to PCI bridge";
410 		break;
411 	case 0x71a18086:
412 		s = "Intel 82443GX host to AGP bridge";
413 		break;
414 	case 0x71a28086:
415 		s = "Intel 82443GX host to PCI bridge (AGP disabled)";
416 		break;
417 	case 0x84c48086:
418 		s = "Intel 82454KX/GX (Orion) host to PCI bridge";
419 		*busnum = pci_cfgread(cfg, 0x4a, 1);
420 		break;
421 	case 0x84ca8086:
422 		/*
423 		 * For the 450nx chipset, there is a whole bundle of
424 		 * things pretending to be host bridges. The MIOC will
425 		 * be seen first and isn't really a pci bridge (the
426 		 * actual busses are attached to the PXB's). We need to
427 		 * read the registers of the MIOC to figure out the
428 		 * bus numbers for the PXB channels.
429 		 *
430 		 * Since the MIOC doesn't have a pci bus attached, we
431 		 * pretend it wasn't there.
432 		 */
433 		pxb[0] = pci_cfgread(cfg, 0xd0, 1); /* BUSNO[0] */
434 		pxb[1] = pci_cfgread(cfg, 0xd1, 1) + 1;	/* SUBA[0]+1 */
435 		pxb[2] = pci_cfgread(cfg, 0xd3, 1); /* BUSNO[1] */
436 		pxb[3] = pci_cfgread(cfg, 0xd4, 1) + 1;	/* SUBA[1]+1 */
437 		return NULL;
438 	case 0x84cb8086:
439 		switch (cfg->slot) {
440 		case 0x12:
441 			s = "Intel 82454NX PXB#0, Bus#A";
442 			*busnum = pxb[0];
443 			break;
444 		case 0x13:
445 			s = "Intel 82454NX PXB#0, Bus#B";
446 			*busnum = pxb[1];
447 			break;
448 		case 0x14:
449 			s = "Intel 82454NX PXB#1, Bus#A";
450 			*busnum = pxb[2];
451 			break;
452 		case 0x15:
453 			s = "Intel 82454NX PXB#1, Bus#B";
454 			*busnum = pxb[3];
455 			break;
456 		}
457 		break;
458 
459 		/* AMD -- vendor 0x1022 */
460 	case 0x70061022:
461 		s = "AMD-751 host to PCI bridge";
462 		break;
463 
464 		/* SiS -- vendor 0x1039 */
465 	case 0x04961039:
466 		s = "SiS 85c496";
467 		break;
468 	case 0x04061039:
469 		s = "SiS 85c501";
470 		break;
471 	case 0x06011039:
472 		s = "SiS 85c601";
473 		break;
474 	case 0x55911039:
475 		s = "SiS 5591 host to PCI bridge";
476 		break;
477 	case 0x00011039:
478 		s = "SiS 5591 host to AGP bridge";
479 		break;
480 
481 		/* VLSI -- vendor 0x1004 */
482 	case 0x00051004:
483 		s = "VLSI 82C592 Host to PCI bridge";
484 		break;
485 
486 		/* XXX Here is MVP3, I got the datasheet but NO M/B to test it  */
487 		/* totally. Please let me know if anything wrong.            -F */
488 		/* XXX need info on the MVP3 -- any takers? */
489 	case 0x05981106:
490 		s = "VIA 82C598MVP (Apollo MVP3) host bridge";
491 		break;
492 
493 		/* AcerLabs -- vendor 0x10b9 */
494 		/* Funny : The datasheet told me vendor id is "10b8",sub-vendor */
495 		/* id is '10b9" but the register always shows "10b9". -Foxfair  */
496 	case 0x154110b9:
497 		s = "AcerLabs M1541 (Aladdin-V) PCI host bridge";
498 		break;
499 
500 		/* OPTi -- vendor 0x1045 */
501 	case 0xc8221045:
502 		s = "OPTi 82C822 host to PCI Bridge";
503 		break;
504 
505 		/* RCC -- vendor 0x1166 */
506 	case 0x00051166:
507 		s = "RCC HE host to PCI bridge";
508 		*busnum = pci_cfgread(cfg, 0x44, 1);
509 		break;
510 
511 	case 0x00061166:
512 		/* FALLTHROUGH */
513 	case 0x00081166:
514 		s = "RCC host to PCI bridge";
515 		*busnum = pci_cfgread(cfg, 0x44, 1);
516 		break;
517 
518 	case 0x00091166:
519 		s = "RCC LE host to PCI bridge";
520 		*busnum = pci_cfgread(cfg, 0x44, 1);
521 		break;
522 
523 		/* Integrated Micro Solutions -- vendor 0x10e0 */
524 	case 0x884910e0:
525 		s = "Integrated Micro Solutions VL Bridge";
526 		break;
527 
528 	default:
529 		if (class == PCIC_BRIDGE && subclass == PCIS_BRIDGE_HOST)
530 			s = "Host to PCI bridge";
531 		break;
532 	}
533 
534 	return s;
535 }
536 
537 /*
538  * Scan the first pci bus for host-pci bridges and add pcib instances
539  * to the nexus for each bridge.
540  */
541 static void
542 nexus_pcib_identify(driver_t *driver, device_t parent)
543 {
544 	pcicfgregs probe;
545 	u_int8_t  hdrtype;
546 	int found = 0;
547 	int pcifunchigh;
548 	int found824xx = 0;
549 
550 	if (pci_cfgopen() == 0)
551 		return;
552 	probe.hose = 0;
553 	probe.bus = 0;
554  retry:
555 	for (probe.slot = 0; probe.slot <= PCI_SLOTMAX; probe.slot++) {
556 		probe.func = 0;
557 		hdrtype = pci_cfgread(&probe, PCIR_HEADERTYPE, 1);
558 		if (hdrtype & PCIM_MFDEV)
559 			pcifunchigh = 7;
560 		else
561 			pcifunchigh = 0;
562 		for (probe.func = 0;
563 		     probe.func <= pcifunchigh;
564 		     probe.func++) {
565 			/*
566 			 * Read the IDs and class from the device.
567 			 */
568 			u_int32_t id;
569 			u_int8_t class, subclass, busnum;
570 			device_t child;
571 			const char *s;
572 
573 			id = pci_cfgread(&probe, PCIR_DEVVENDOR, 4);
574 			if (id == -1)
575 				continue;
576 			class = pci_cfgread(&probe, PCIR_CLASS, 1);
577 			subclass = pci_cfgread(&probe, PCIR_SUBCLASS, 1);
578 
579 			s = nexus_pcib_is_host_bridge(&probe, id,
580 						      class, subclass,
581 						      &busnum);
582 			if (s) {
583 				/*
584 				 * Add at priority 100 to make sure we
585 				 * go after any motherboard resources
586 				 */
587 				child = BUS_ADD_CHILD(parent, 100,
588 						      "pcib", busnum);
589 				device_set_desc(child, s);
590 				found = 1;
591 				if (id == 0x12258086)
592 					found824xx = 1;
593 			}
594 		}
595 	}
596 	if (found824xx && probe.bus == 0) {
597 		probe.bus++;
598 		goto retry;
599 	}
600 
601 	/*
602 	 * Make sure we add at least one bridge since some old
603 	 * hardware doesn't actually have a host-pci bridge device.
604 	 * Note that pci_cfgopen() thinks we have PCI devices..
605 	 */
606 	if (!found) {
607 		if (bootverbose)
608 			printf(
609 	"nexus_pcib_identify: no bridge found, adding pcib0 anyway\n");
610 		BUS_ADD_CHILD(parent, 100, "pcib", 0);
611 	}
612 }
613 
614 static int
615 nexus_pcib_probe(device_t dev)
616 {
617 	if (pci_cfgopen() != 0) {
618 		device_add_child(dev, "pci", device_get_unit(dev));
619 		return 0;
620 	}
621 	return ENXIO;
622 }
623 
624 static device_method_t nexus_pcib_methods[] = {
625 	/* Device interface */
626 	DEVMETHOD(device_identify,	nexus_pcib_identify),
627 	DEVMETHOD(device_probe,		nexus_pcib_probe),
628 	DEVMETHOD(device_attach,	bus_generic_attach),
629 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
630 	DEVMETHOD(device_suspend,	bus_generic_suspend),
631 	DEVMETHOD(device_resume,	bus_generic_resume),
632 
633 	/* Bus interface */
634 	DEVMETHOD(bus_print_child,	bus_generic_print_child),
635 	DEVMETHOD(bus_alloc_resource,	bus_generic_alloc_resource),
636 	DEVMETHOD(bus_release_resource,	bus_generic_release_resource),
637 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
638 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
639 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
640 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
641 
642 	{ 0, 0 }
643 };
644 
645 static driver_t nexus_pcib_driver = {
646 	"pcib",
647 	nexus_pcib_methods,
648 	1,
649 };
650 
651 DRIVER_MODULE(pcib, nexus, nexus_pcib_driver, pcib_devclass, 0, 0);
652