xref: /netbsd-src/sys/dev/pci/pci_map.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /*	$NetBSD: pci_map.c,v 1.40 2020/05/05 16:58:11 bouyer Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Charles M. Hannum; by William R. Studenmund; by Jason R. Thorpe.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * PCI device mapping.
34  */
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: pci_map.c,v 1.40 2020/05/05 16:58:11 bouyer Exp $");
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/device.h>
42 
43 #include <dev/pci/pcireg.h>
44 #include <dev/pci/pcivar.h>
45 
46 bool pci_mapreg_map_enable_decode = true;
47 
48 static int
49 pci_io_find(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t type,
50     bus_addr_t *basep, bus_size_t *sizep, int *flagsp)
51 {
52 	pcireg_t address, mask, csr;
53 	int s;
54 
55 	if (reg < PCI_MAPREG_START ||
56 #if 0
57 	    /*
58 	     * Can't do this check; some devices have mapping registers
59 	     * way out in left field.
60 	     */
61 	    reg >= PCI_MAPREG_END ||
62 #endif
63 	    (reg & 3))
64 		panic("pci_io_find: bad request");
65 
66 	/*
67 	 * Section 6.2.5.1, `Address Maps', tells us that:
68 	 *
69 	 * 1) The builtin software should have already mapped the device in a
70 	 * reasonable way.
71 	 *
72 	 * 2) A device which wants 2^n bytes of memory will hardwire the bottom
73 	 * n bits of the address to 0.  As recommended, we write all 1s and see
74 	 * what we get back.
75 	 */
76 	s = splhigh();
77 	address = pci_conf_read(pc, tag, reg);
78 	/*
79 	 * Disable decoding via the command register before writing to the
80 	 * BAR register. Changing the decoding address to all-one is
81 	 * not a valid address and could have side effects.
82 	 */
83 	csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
84 	pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG,
85 	    csr & ~PCI_COMMAND_IO_ENABLE) ;
86 	pci_conf_write(pc, tag, reg, 0xffffffff);
87 	mask = pci_conf_read(pc, tag, reg);
88 	pci_conf_write(pc, tag, reg, address);
89 	pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG, csr);
90 	splx(s);
91 
92 	if (PCI_MAPREG_TYPE(address) != PCI_MAPREG_TYPE_IO) {
93 		aprint_debug("pci_io_find: expected type i/o, found mem\n");
94 		return 1;
95 	}
96 
97 	if (PCI_MAPREG_IO_SIZE(mask) == 0) {
98 		aprint_debug("pci_io_find: void region\n");
99 		return 1;
100 	}
101 
102 	if (basep != NULL)
103 		*basep = PCI_MAPREG_IO_ADDR(address);
104 	if (sizep != NULL)
105 		*sizep = PCI_MAPREG_IO_SIZE(mask);
106 	if (flagsp != NULL)
107 		*flagsp = 0;
108 
109 	return 0;
110 }
111 
112 static int
113 pci_mem_find(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t type,
114     bus_addr_t *basep, bus_size_t *sizep, int *flagsp)
115 {
116 	pcireg_t address, mask, address1 = 0, mask1 = 0xffffffff;
117 	uint64_t waddress, wmask;
118 	int s, is64bit, isrom;
119 	pcireg_t csr;
120 
121 	is64bit = (PCI_MAPREG_MEM_TYPE(type) == PCI_MAPREG_MEM_TYPE_64BIT);
122 	isrom = (reg == PCI_MAPREG_ROM);
123 
124 	if ((!isrom) && (reg < PCI_MAPREG_START ||
125 #if 0
126 	    /*
127 	     * Can't do this check; some devices have mapping registers
128 	     * way out in left field.
129 	     */
130 	    reg >= PCI_MAPREG_END ||
131 #endif
132 	    (reg & 3)))
133 		panic("pci_mem_find: bad request");
134 
135 	if (is64bit && (reg + 4) >= PCI_MAPREG_END)
136 		panic("pci_mem_find: bad 64-bit request");
137 
138 	/*
139 	 * Section 6.2.5.1, `Address Maps', tells us that:
140 	 *
141 	 * 1) The builtin software should have already mapped the device in a
142 	 * reasonable way.
143 	 *
144 	 * 2) A device which wants 2^n bytes of memory will hardwire the bottom
145 	 * n bits of the address to 0.  As recommended, we write all 1s and see
146 	 * what we get back.  Only probe the upper BAR of a mem64 BAR if bit 31
147 	 * is readonly.
148 	 */
149 	s = splhigh();
150 	address = pci_conf_read(pc, tag, reg);
151 	csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
152 	/*
153 	 * Disable decoding via the command register before writing to the
154 	 * BAR register. Changing the decoding address to all-one is
155 	 * not a valid address and could have side effects.
156 	 */
157 	pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG,
158 	    csr & ~PCI_COMMAND_MEM_ENABLE) ;
159 	pci_conf_write(pc, tag, reg, 0xffffffff);
160 	mask = pci_conf_read(pc, tag, reg);
161 	pci_conf_write(pc, tag, reg, address);
162 	if (is64bit) {
163 		address1 = pci_conf_read(pc, tag, reg + 4);
164 		if ((mask & 0x80000000) == 0) {
165 			pci_conf_write(pc, tag, reg + 4, 0xffffffff);
166 			mask1 = pci_conf_read(pc, tag, reg + 4);
167 			pci_conf_write(pc, tag, reg + 4, address1);
168 		}
169 	}
170 	pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG, csr);
171 	splx(s);
172 
173 	if (!isrom) {
174 		/*
175 		 * roms should have an enable bit instead of a memory
176 		 * type decoder bit.  For normal BARs, make sure that
177 		 * the address decoder type matches what we asked for.
178 		 */
179 		if (PCI_MAPREG_TYPE(address) != PCI_MAPREG_TYPE_MEM) {
180 			printf("pci_mem_find: expected type mem, found i/o\n");
181 			return 1;
182 		}
183 		/* XXX Allow 64bit bars for 32bit requests.*/
184 		if (PCI_MAPREG_MEM_TYPE(address) !=
185 		    PCI_MAPREG_MEM_TYPE(type) &&
186 		    PCI_MAPREG_MEM_TYPE(address) !=
187 		    PCI_MAPREG_MEM_TYPE_64BIT) {
188 			printf("pci_mem_find: "
189 			    "expected mem type %08x, found %08x\n",
190 			    PCI_MAPREG_MEM_TYPE(type),
191 			    PCI_MAPREG_MEM_TYPE(address));
192 			return 1;
193 		}
194 	}
195 
196 	waddress = (uint64_t)address1 << 32UL | address;
197 	wmask = (uint64_t)mask1 << 32UL | mask;
198 
199 	if ((is64bit && PCI_MAPREG_MEM64_SIZE(wmask) == 0) ||
200 	    (!is64bit && PCI_MAPREG_MEM_SIZE(mask) == 0)) {
201 		aprint_debug("pci_mem_find: void region\n");
202 		return 1;
203 	}
204 
205 	switch (PCI_MAPREG_MEM_TYPE(address)) {
206 	case PCI_MAPREG_MEM_TYPE_32BIT:
207 	case PCI_MAPREG_MEM_TYPE_32BIT_1M:
208 		break;
209 	case PCI_MAPREG_MEM_TYPE_64BIT:
210 		/*
211 		 * Handle the case of a 64-bit memory register on a
212 		 * platform with 32-bit addressing.  Make sure that
213 		 * the address assigned and the device's memory size
214 		 * fit in 32 bits.  We implicitly assume that if
215 		 * bus_addr_t is 64-bit, then so is bus_size_t.
216 		 */
217 		if (sizeof(uint64_t) > sizeof(bus_addr_t) &&
218 		    (address1 != 0 || mask1 != 0xffffffff)) {
219 			printf("pci_mem_find: 64-bit memory map which is "
220 			    "inaccessible on a 32-bit platform\n");
221 			return 1;
222 		}
223 		break;
224 	default:
225 		printf("pci_mem_find: reserved mapping register type\n");
226 		return 1;
227 	}
228 
229 	if (sizeof(uint64_t) > sizeof(bus_addr_t)) {
230 		if (basep != NULL)
231 			*basep = PCI_MAPREG_MEM_ADDR(address);
232 		if (sizep != NULL)
233 			*sizep = PCI_MAPREG_MEM_SIZE(mask);
234 	} else {
235 		if (basep != NULL)
236 			*basep = PCI_MAPREG_MEM64_ADDR(waddress);
237 		if (sizep != NULL)
238 			*sizep = PCI_MAPREG_MEM64_SIZE(wmask);
239 	}
240 	if (flagsp != NULL)
241 		*flagsp = (isrom || PCI_MAPREG_MEM_PREFETCHABLE(address)) ?
242 		    BUS_SPACE_MAP_PREFETCHABLE : 0;
243 
244 	return 0;
245 }
246 
247 #define _PCI_MAPREG_TYPEBITS(reg) \
248 	(PCI_MAPREG_TYPE(reg) == PCI_MAPREG_TYPE_IO ? \
249 	reg & PCI_MAPREG_TYPE_MASK : \
250 	reg & (PCI_MAPREG_TYPE_MASK|PCI_MAPREG_MEM_TYPE_MASK))
251 
252 pcireg_t
253 pci_mapreg_type(pci_chipset_tag_t pc, pcitag_t tag, int reg)
254 {
255 
256 	return _PCI_MAPREG_TYPEBITS(pci_conf_read(pc, tag, reg));
257 }
258 
259 int
260 pci_mapreg_probe(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t *typep)
261 {
262 	pcireg_t address, mask, csr;
263 	int s;
264 
265 	s = splhigh();
266 	address = pci_conf_read(pc, tag, reg);
267 	/*
268 	 * Disable decoding via the command register before writing to the
269 	 * BAR register. Changing the decoding address to all-one is
270 	 * not a valid address and could have side effects.
271 	 */
272 	csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
273 	if (PCI_MAPREG_TYPE(address) == PCI_MAPREG_TYPE_IO) {
274 		pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG,
275 		    csr & ~PCI_COMMAND_IO_ENABLE);
276 	} else {
277 		pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG,
278 		    csr & ~PCI_COMMAND_MEM_ENABLE);
279 	}
280 	pci_conf_write(pc, tag, reg, 0xffffffff);
281 	mask = pci_conf_read(pc, tag, reg);
282 	pci_conf_write(pc, tag, reg, address);
283 	pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG, csr);
284 	splx(s);
285 
286 	if (mask == 0) /* unimplemented mapping register */
287 		return 0;
288 
289 	if (typep != NULL)
290 		*typep = _PCI_MAPREG_TYPEBITS(address);
291 	return 1;
292 }
293 
294 int
295 pci_mapreg_info(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t type,
296     bus_addr_t *basep, bus_size_t *sizep, int *flagsp)
297 {
298 
299 	if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO)
300 		return pci_io_find(pc, tag, reg, type, basep, sizep,
301 		    flagsp);
302 	else
303 		return pci_mem_find(pc, tag, reg, type, basep, sizep,
304 		    flagsp);
305 }
306 
307 int
308 pci_mapreg_map(const struct pci_attach_args *pa, int reg, pcireg_t type,
309     int busflags, bus_space_tag_t *tagp, bus_space_handle_t *handlep,
310     bus_addr_t *basep, bus_size_t *sizep)
311 {
312 	return pci_mapreg_submap(pa, reg, type, busflags, 0, 0, tagp,
313 	    handlep, basep, sizep);
314 }
315 
316 int
317 pci_mapreg_submap(const struct pci_attach_args *pa, int reg, pcireg_t type,
318     int busflags, bus_size_t reqsize, bus_size_t offset, bus_space_tag_t *tagp,
319 	bus_space_handle_t *handlep, bus_addr_t *basep, bus_size_t *sizep)
320 {
321 	bus_space_tag_t tag;
322 	bus_space_handle_t handle;
323 	bus_addr_t base;
324 	bus_size_t realmaxsize;
325 	pcireg_t csr;
326 	int flags, s;
327 
328 	if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO) {
329 		if ((pa->pa_flags & PCI_FLAGS_IO_OKAY) == 0)
330 			return 1;
331 		if (pci_io_find(pa->pa_pc, pa->pa_tag, reg, type, &base,
332 		    &realmaxsize, &flags))
333 			return 1;
334 		tag = pa->pa_iot;
335 	} else {
336 		if ((pa->pa_flags & PCI_FLAGS_MEM_OKAY) == 0)
337 			return 1;
338 		if (pci_mem_find(pa->pa_pc, pa->pa_tag, reg, type, &base,
339 		    &realmaxsize, &flags))
340 			return 1;
341 		tag = pa->pa_memt;
342 	}
343 
344 	if (reg == PCI_MAPREG_ROM) {
345 		pcireg_t 	mask;
346 		/* we have to enable the ROM address decoder... */
347 		s = splhigh();
348 		mask = pci_conf_read(pa->pa_pc, pa->pa_tag, reg);
349 		mask |= PCI_MAPREG_ROM_ENABLE;
350 		pci_conf_write(pa->pa_pc, pa->pa_tag, reg, mask);
351 		splx(s);
352 	}
353 
354 	/* If we're called with maxsize/offset of 0, behave like
355 	 * pci_mapreg_map.
356 	 */
357 
358 	reqsize = (reqsize != 0) ? reqsize : realmaxsize;
359 	base += offset;
360 
361 	if (realmaxsize < (offset + reqsize))
362 		return 1;
363 
364 	if (bus_space_map(tag, base, reqsize, busflags, &handle))
365 		return 1;
366 
367 	if (pci_mapreg_map_enable_decode) {
368 		s = splhigh();
369 		csr = pci_conf_read(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG);
370 		csr |= (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO) ?
371 		    PCI_COMMAND_IO_ENABLE : PCI_COMMAND_MEM_ENABLE;
372 		pci_conf_write(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG, csr);
373 		splx(s);
374 	}
375 
376 	if (tagp != NULL)
377 		*tagp = tag;
378 	if (handlep != NULL)
379 		*handlep = handle;
380 	if (basep != NULL)
381 		*basep = base;
382 	if (sizep != NULL)
383 		*sizep = reqsize;
384 
385 	return 0;
386 }
387 
388 int
389 pci_find_rom(const struct pci_attach_args *pa, bus_space_tag_t bst,
390     bus_space_handle_t bsh, bus_size_t sz, int type,
391     bus_space_handle_t *romh, bus_size_t *romsz)
392 {
393 	bus_size_t	offset = 0, imagesz;
394 	uint16_t	ptr;
395 	int		done = 0;
396 
397 	/*
398 	 * no upper bound check; i cannot imagine a 4GB ROM, but
399 	 * it appears the spec would allow it!
400 	 */
401 	if (sz < 1024)
402 		return 1;
403 
404 	while (offset < sz && !done){
405 		struct pci_rom_header	hdr;
406 		struct pci_rom		rom;
407 
408 		hdr.romh_magic = bus_space_read_2(bst, bsh,
409 		    offset + offsetof (struct pci_rom_header, romh_magic));
410 		hdr.romh_data_ptr = bus_space_read_2(bst, bsh,
411 		    offset + offsetof (struct pci_rom_header, romh_data_ptr));
412 
413 		/* no warning: quite possibly ROM is simply not populated */
414 		if (hdr.romh_magic != PCI_ROM_HEADER_MAGIC)
415 			return 1;
416 
417 		ptr = offset + hdr.romh_data_ptr;
418 
419 		if (ptr > sz) {
420 			printf("pci_find_rom: rom data ptr out of range\n");
421 			return 1;
422 		}
423 
424 		rom.rom_signature = bus_space_read_4(bst, bsh, ptr);
425 		rom.rom_vendor = bus_space_read_2(bst, bsh, ptr +
426 		    offsetof(struct pci_rom, rom_vendor));
427 		rom.rom_product = bus_space_read_2(bst, bsh, ptr +
428 		    offsetof(struct pci_rom, rom_product));
429 		rom.rom_class = bus_space_read_1(bst, bsh,
430 		    ptr + offsetof (struct pci_rom, rom_class));
431 		rom.rom_subclass = bus_space_read_1(bst, bsh,
432 		    ptr + offsetof (struct pci_rom, rom_subclass));
433 		rom.rom_interface = bus_space_read_1(bst, bsh,
434 		    ptr + offsetof (struct pci_rom, rom_interface));
435 		rom.rom_len = bus_space_read_2(bst, bsh,
436 		    ptr + offsetof (struct pci_rom, rom_len));
437 		rom.rom_code_type = bus_space_read_1(bst, bsh,
438 		    ptr + offsetof (struct pci_rom, rom_code_type));
439 		rom.rom_indicator = bus_space_read_1(bst, bsh,
440 		    ptr + offsetof (struct pci_rom, rom_indicator));
441 
442 		if (rom.rom_signature != PCI_ROM_SIGNATURE) {
443 			printf("pci_find_rom: bad rom data signature\n");
444 			return 1;
445 		}
446 
447 		imagesz = rom.rom_len * 512;
448 
449 		if ((rom.rom_vendor == PCI_VENDOR(pa->pa_id)) &&
450 		    (rom.rom_product == PCI_PRODUCT(pa->pa_id)) &&
451 		    (rom.rom_class == PCI_CLASS(pa->pa_class)) &&
452 		    (rom.rom_subclass == PCI_SUBCLASS(pa->pa_class)) &&
453 		    (rom.rom_interface == PCI_INTERFACE(pa->pa_class)) &&
454 		    (rom.rom_code_type == type)) {
455 			*romsz = imagesz;
456 			bus_space_subregion(bst, bsh, offset, imagesz, romh);
457 			return 0;
458 		}
459 
460 		/* last image check */
461 		if (rom.rom_indicator & PCI_ROM_INDICATOR_LAST)
462 			return 1;
463 
464 		/* offset by size */
465 		offset += imagesz;
466 	}
467 	return 1;
468 }
469