xref: /freebsd/sys/dev/amdpm/amdpm.c (revision 732a02b4e77866604a120a275c082bb6221bd2ff)
1 /*-
2  * Copyright (c) 2000 Matthew C. Forman
3  *
4  * Based (heavily) on alpm.c which is:
5  *
6  * Copyright (c) 1998, 1999 Nicolas Souchu
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 /*
32  * Power management function/SMBus function support for the AMD 756 chip.
33  */
34 
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include <sys/param.h>
39 #include <sys/bus.h>
40 #include <sys/kernel.h>
41 #include <sys/lock.h>
42 #include <sys/module.h>
43 #include <sys/mutex.h>
44 #include <sys/systm.h>
45 
46 #include <machine/bus.h>
47 #include <machine/resource.h>
48 #include <sys/rman.h>
49 
50 #include <dev/pci/pcivar.h>
51 #include <dev/pci/pcireg.h>
52 
53 #include <dev/smbus/smbconf.h>
54 #include "smbus_if.h"
55 
56 #define AMDPM_DEBUG(x)	if (amdpm_debug) (x)
57 
58 #ifdef DEBUG
59 static int amdpm_debug = 1;
60 #else
61 static int amdpm_debug = 0;
62 #endif
63 
64 #define AMDPM_VENDORID_AMD 0x1022
65 #define AMDPM_DEVICEID_AMD756PM 0x740b
66 #define AMDPM_DEVICEID_AMD766PM 0x7413
67 #define AMDPM_DEVICEID_AMD768PM 0x7443
68 #define AMDPM_DEVICEID_AMD8111PM 0x746B
69 
70 #define AMDPM_VENDORID_HYGON 0x1d94
71 
72 /* nVidia nForce chipset */
73 #define AMDPM_VENDORID_NVIDIA 0x10de
74 #define AMDPM_DEVICEID_NF_SMB 0x01b4
75 
76 /* PCI Configuration space registers */
77 #define AMDPCI_PMBASE 0x58
78 #define NFPCI_PMBASE  0x14
79 
80 #define AMDPCI_GEN_CONFIG_PM 0x41
81 #define AMDPCI_PMIOEN (1<<7)
82 
83 #define AMDPCI_SCIINT_CONFIG_PM 0x42
84 #define AMDPCI_SCISEL_IRQ11 11
85 
86 #define AMDPCI_REVID 0x08
87 
88 /*
89  * I/O registers.
90  * Base address programmed via AMDPCI_PMBASE.
91  */
92 
93 #define AMDSMB_GLOBAL_STATUS (0x00)
94 #define AMDSMB_GS_TO_STS (1<<5)
95 #define AMDSMB_GS_HCYC_STS (1<<4)
96 #define AMDSMB_GS_HST_STS (1<<3)
97 #define AMDSMB_GS_PRERR_STS (1<<2)
98 #define AMDSMB_GS_COL_STS (1<<1)
99 #define AMDSMB_GS_ABRT_STS (1<<0)
100 #define AMDSMB_GS_CLEAR_STS (AMDSMB_GS_TO_STS|AMDSMB_GS_HCYC_STS|AMDSMB_GS_PRERR_STS|AMDSMB_GS_COL_STS|AMDSMB_GS_ABRT_STS)
101 
102 #define AMDSMB_GLOBAL_ENABLE (0x02)
103 #define AMDSMB_GE_ABORT (1<<5)
104 #define AMDSMB_GE_HCYC_EN (1<<4)
105 #define AMDSMB_GE_HOST_STC (1<<3)
106 #define AMDSMB_GE_CYC_QUICK 0
107 #define AMDSMB_GE_CYC_BYTE 1
108 #define AMDSMB_GE_CYC_BDATA 2
109 #define AMDSMB_GE_CYC_WDATA 3
110 #define AMDSMB_GE_CYC_PROCCALL 4
111 #define AMDSMB_GE_CYC_BLOCK 5
112 
113 #define	LSB		0x1	/* XXX: Better name: Read/Write? */
114 
115 #define AMDSMB_HSTADDR  (0x04)
116 #define AMDSMB_HSTDATA  (0x06)
117 #define AMDSMB_HSTCMD   (0x08)
118 #define AMDSMB_HSTDFIFO (0x09)
119 #define AMDSMB_HSLVDATA (0x0A)
120 #define AMDSMB_HSLVDA   (0x0C)
121 #define AMDSMB_HSLVDDR  (0x0E)
122 #define AMDSMB_SNPADDR  (0x0F)
123 
124 struct amdpm_softc {
125 	int base;
126 	int rid;
127 	struct resource *res;
128 	device_t smbus;
129 	struct mtx lock;
130 };
131 
132 #define	AMDPM_LOCK(amdpm)		mtx_lock(&(amdpm)->lock)
133 #define	AMDPM_UNLOCK(amdpm)		mtx_unlock(&(amdpm)->lock)
134 #define	AMDPM_LOCK_ASSERT(amdpm)	mtx_assert(&(amdpm)->lock, MA_OWNED)
135 
136 #define AMDPM_SMBINB(amdpm,register) \
137 	(bus_read_1(amdpm->res, register))
138 #define AMDPM_SMBOUTB(amdpm,register,value) \
139 	(bus_write_1(amdpm->res, register, value))
140 #define AMDPM_SMBINW(amdpm,register) \
141 	(bus_read_2(amdpm->res, register))
142 #define AMDPM_SMBOUTW(amdpm,register,value) \
143 	(bus_write_2(amdpm->res, register, value))
144 
145 static int	amdpm_detach(device_t dev);
146 
147 static int
148 amdpm_probe(device_t dev)
149 {
150 	u_long base;
151 	u_int16_t vid;
152 	u_int16_t did;
153 
154 	vid = pci_get_vendor(dev);
155 	did = pci_get_device(dev);
156 	if ((vid == AMDPM_VENDORID_AMD) &&
157 	    ((did == AMDPM_DEVICEID_AMD756PM) ||
158 	     (did == AMDPM_DEVICEID_AMD766PM) ||
159 	     (did == AMDPM_DEVICEID_AMD768PM) ||
160 	     (did == AMDPM_DEVICEID_AMD8111PM))) {
161 		device_set_desc(dev, "AMD 756/766/768/8111 Power Management Controller");
162 
163 		/*
164 		 * We have to do this, since the BIOS won't give us the
165 		 * resource info (not mine, anyway).
166 		 */
167 		base = pci_read_config(dev, AMDPCI_PMBASE, 4);
168 		base &= 0xff00;
169 		bus_set_resource(dev, SYS_RES_IOPORT, AMDPCI_PMBASE,
170 				 base+0xe0, 32);
171 		return (BUS_PROBE_DEFAULT);
172 	}
173 
174 	if ((vid == AMDPM_VENDORID_NVIDIA) &&
175 	    (did == AMDPM_DEVICEID_NF_SMB)) {
176 		device_set_desc(dev, "nForce SMBus Controller");
177 
178 		/*
179 		* We have to do this, since the BIOS won't give us the
180 		* resource info (not mine, anyway).
181 		*/
182 		base = pci_read_config(dev, NFPCI_PMBASE, 4);
183 		base &= 0xff00;
184 		bus_set_resource(dev, SYS_RES_IOPORT, NFPCI_PMBASE,
185 				 base, 32);
186 
187 		return (BUS_PROBE_DEFAULT);
188 	}
189 
190 	return ENXIO;
191 }
192 
193 static int
194 amdpm_attach(device_t dev)
195 {
196 	struct amdpm_softc *amdpm_sc = device_get_softc(dev);
197 	u_char val_b;
198 
199 	/* Enable I/O block access */
200 	val_b = pci_read_config(dev, AMDPCI_GEN_CONFIG_PM, 1);
201 	pci_write_config(dev, AMDPCI_GEN_CONFIG_PM, val_b | AMDPCI_PMIOEN, 1);
202 
203 	/* Allocate I/O space */
204 	if (pci_get_vendor(dev) == AMDPM_VENDORID_AMD ||
205 	    pci_get_vendor(dev) == AMDPM_VENDORID_HYGON)
206 		amdpm_sc->rid = AMDPCI_PMBASE;
207 	else
208 		amdpm_sc->rid = NFPCI_PMBASE;
209 	amdpm_sc->res = bus_alloc_resource_any(dev, SYS_RES_IOPORT,
210 		&amdpm_sc->rid, RF_ACTIVE);
211 
212 	if (amdpm_sc->res == NULL) {
213 		device_printf(dev, "could not map i/o space\n");
214 		return (ENXIO);
215 	}
216 
217 	mtx_init(&amdpm_sc->lock, device_get_nameunit(dev), "amdpm", MTX_DEF);
218 
219 	/* Allocate a new smbus device */
220 	amdpm_sc->smbus = device_add_child(dev, "smbus", -1);
221 	if (!amdpm_sc->smbus) {
222 		amdpm_detach(dev);
223 		return (EINVAL);
224 	}
225 
226 	bus_generic_attach(dev);
227 
228 	return (0);
229 }
230 
231 static int
232 amdpm_detach(device_t dev)
233 {
234 	struct amdpm_softc *amdpm_sc = device_get_softc(dev);
235 
236 	if (amdpm_sc->smbus) {
237 		device_delete_child(dev, amdpm_sc->smbus);
238 		amdpm_sc->smbus = NULL;
239 	}
240 
241 	mtx_destroy(&amdpm_sc->lock);
242 	if (amdpm_sc->res)
243 		bus_release_resource(dev, SYS_RES_IOPORT, amdpm_sc->rid,
244 				     amdpm_sc->res);
245 
246 	return (0);
247 }
248 
249 static int
250 amdpm_callback(device_t dev, int index, void *data)
251 {
252 	int error = 0;
253 
254 	switch (index) {
255 	case SMB_REQUEST_BUS:
256 	case SMB_RELEASE_BUS:
257 		break;
258 	default:
259 		error = EINVAL;
260 	}
261 
262 	return (error);
263 }
264 
265 static int
266 amdpm_clear(struct amdpm_softc *sc)
267 {
268 
269 	AMDPM_LOCK_ASSERT(sc);
270 	AMDPM_SMBOUTW(sc, AMDSMB_GLOBAL_STATUS, AMDSMB_GS_CLEAR_STS);
271 	DELAY(10);
272 
273 	return (0);
274 }
275 
276 #if 0
277 static int
278 amdpm_abort(struct amdpm_softc *sc)
279 {
280 	u_short l;
281 
282 	l = AMDPM_SMBINW(sc, AMDSMB_GLOBAL_ENABLE);
283 	AMDPM_SMBOUTW(sc, AMDSMB_GLOBAL_ENABLE, l | AMDSMB_GE_ABORT);
284 
285 	return (0);
286 }
287 #endif
288 
289 static int
290 amdpm_idle(struct amdpm_softc *sc)
291 {
292 	u_short sts;
293 
294 	AMDPM_LOCK_ASSERT(sc);
295 	sts = AMDPM_SMBINW(sc, AMDSMB_GLOBAL_STATUS);
296 
297 	AMDPM_DEBUG(printf("amdpm: busy? STS=0x%x\n", sts));
298 
299 	return (~(sts & AMDSMB_GS_HST_STS));
300 }
301 
302 /*
303  * Poll the SMBus controller
304  */
305 static int
306 amdpm_wait(struct amdpm_softc *sc)
307 {
308 	int count = 10000;
309 	u_short sts = 0;
310 	int error;
311 
312 	AMDPM_LOCK_ASSERT(sc);
313 	/* Wait for command to complete (SMBus controller is idle) */
314 	while(count--) {
315 		DELAY(10);
316 		sts = AMDPM_SMBINW(sc, AMDSMB_GLOBAL_STATUS);
317 		if (!(sts & AMDSMB_GS_HST_STS))
318 			break;
319 	}
320 
321 	AMDPM_DEBUG(printf("amdpm: STS=0x%x (count=%d)\n", sts, count));
322 
323 	error = SMB_ENOERR;
324 
325 	if (!count)
326 		error |= SMB_ETIMEOUT;
327 
328 	if (sts & AMDSMB_GS_ABRT_STS)
329 		error |= SMB_EABORT;
330 
331 	if (sts & AMDSMB_GS_COL_STS)
332 		error |= SMB_ENOACK;
333 
334 	if (sts & AMDSMB_GS_PRERR_STS)
335 		error |= SMB_EBUSERR;
336 
337 	if (error != SMB_ENOERR)
338 		amdpm_clear(sc);
339 
340 	return (error);
341 }
342 
343 static int
344 amdpm_quick(device_t dev, u_char slave, int how)
345 {
346 	struct amdpm_softc *sc = (struct amdpm_softc *)device_get_softc(dev);
347 	int error;
348 	u_short l;
349 
350 	AMDPM_LOCK(sc);
351 	amdpm_clear(sc);
352 	if (!amdpm_idle(sc)) {
353 		AMDPM_UNLOCK(sc);
354 		return (EBUSY);
355 	}
356 
357 	switch (how) {
358 	case SMB_QWRITE:
359 		AMDPM_DEBUG(printf("amdpm: QWRITE to 0x%x", slave));
360 		AMDPM_SMBOUTW(sc, AMDSMB_HSTADDR, slave & ~LSB);
361 		break;
362 	case SMB_QREAD:
363 		AMDPM_DEBUG(printf("amdpm: QREAD to 0x%x", slave));
364 		AMDPM_SMBOUTW(sc, AMDSMB_HSTADDR, slave | LSB);
365 		break;
366 	default:
367 		panic("%s: unknown QUICK command (%x)!", __func__, how);
368 	}
369 	l = AMDPM_SMBINW(sc, AMDSMB_GLOBAL_ENABLE);
370 	AMDPM_SMBOUTW(sc, AMDSMB_GLOBAL_ENABLE, (l & 0xfff8) | AMDSMB_GE_CYC_QUICK | AMDSMB_GE_HOST_STC);
371 
372 	error = amdpm_wait(sc);
373 
374 	AMDPM_DEBUG(printf(", error=0x%x\n", error));
375 	AMDPM_UNLOCK(sc);
376 
377 	return (error);
378 }
379 
380 static int
381 amdpm_sendb(device_t dev, u_char slave, char byte)
382 {
383 	struct amdpm_softc *sc = (struct amdpm_softc *)device_get_softc(dev);
384 	int error;
385 	u_short l;
386 
387 	AMDPM_LOCK(sc);
388 	amdpm_clear(sc);
389 	if (!amdpm_idle(sc)) {
390 		AMDPM_UNLOCK(sc);
391 		return (SMB_EBUSY);
392 	}
393 
394 	AMDPM_SMBOUTW(sc, AMDSMB_HSTADDR, slave & ~LSB);
395 	AMDPM_SMBOUTW(sc, AMDSMB_HSTDATA, byte);
396 	l = AMDPM_SMBINW(sc, AMDSMB_GLOBAL_ENABLE);
397 	AMDPM_SMBOUTW(sc, AMDSMB_GLOBAL_ENABLE, (l & 0xfff8) | AMDSMB_GE_CYC_BYTE | AMDSMB_GE_HOST_STC);
398 
399 	error = amdpm_wait(sc);
400 
401 	AMDPM_DEBUG(printf("amdpm: SENDB to 0x%x, byte=0x%x, error=0x%x\n", slave, byte, error));
402 	AMDPM_UNLOCK(sc);
403 
404 	return (error);
405 }
406 
407 static int
408 amdpm_recvb(device_t dev, u_char slave, char *byte)
409 {
410 	struct amdpm_softc *sc = (struct amdpm_softc *)device_get_softc(dev);
411 	int error;
412 	u_short l;
413 
414 	AMDPM_LOCK(sc);
415 	amdpm_clear(sc);
416 	if (!amdpm_idle(sc)) {
417 		AMDPM_UNLOCK(sc);
418 		return (SMB_EBUSY);
419 	}
420 
421 	AMDPM_SMBOUTW(sc, AMDSMB_HSTADDR, slave | LSB);
422 	l = AMDPM_SMBINW(sc, AMDSMB_GLOBAL_ENABLE);
423 	AMDPM_SMBOUTW(sc, AMDSMB_GLOBAL_ENABLE, (l & 0xfff8) | AMDSMB_GE_CYC_BYTE | AMDSMB_GE_HOST_STC);
424 
425 	if ((error = amdpm_wait(sc)) == SMB_ENOERR)
426 		*byte = AMDPM_SMBINW(sc, AMDSMB_HSTDATA);
427 
428 	AMDPM_DEBUG(printf("amdpm: RECVB from 0x%x, byte=0x%x, error=0x%x\n", slave, *byte, error));
429 	AMDPM_UNLOCK(sc);
430 
431 	return (error);
432 }
433 
434 static int
435 amdpm_writeb(device_t dev, u_char slave, char cmd, char byte)
436 {
437 	struct amdpm_softc *sc = (struct amdpm_softc *)device_get_softc(dev);
438 	int error;
439 	u_short l;
440 
441 	AMDPM_LOCK(sc);
442 	amdpm_clear(sc);
443 	if (!amdpm_idle(sc)) {
444 		AMDPM_UNLOCK(sc);
445 		return (SMB_EBUSY);
446 	}
447 
448 	AMDPM_SMBOUTW(sc, AMDSMB_HSTADDR, slave & ~LSB);
449 	AMDPM_SMBOUTW(sc, AMDSMB_HSTDATA, byte);
450 	AMDPM_SMBOUTB(sc, AMDSMB_HSTCMD, cmd);
451 	l = AMDPM_SMBINW(sc, AMDSMB_GLOBAL_ENABLE);
452 	AMDPM_SMBOUTW(sc, AMDSMB_GLOBAL_ENABLE, (l & 0xfff8) | AMDSMB_GE_CYC_BDATA | AMDSMB_GE_HOST_STC);
453 
454 	error = amdpm_wait(sc);
455 
456 	AMDPM_DEBUG(printf("amdpm: WRITEB to 0x%x, cmd=0x%x, byte=0x%x, error=0x%x\n", slave, cmd, byte, error));
457 	AMDPM_UNLOCK(sc);
458 
459 	return (error);
460 }
461 
462 static int
463 amdpm_readb(device_t dev, u_char slave, char cmd, char *byte)
464 {
465 	struct amdpm_softc *sc = (struct amdpm_softc *)device_get_softc(dev);
466 	int error;
467 	u_short l;
468 
469 	AMDPM_LOCK(sc);
470 	amdpm_clear(sc);
471 	if (!amdpm_idle(sc)) {
472 		AMDPM_UNLOCK(sc);
473 		return (SMB_EBUSY);
474 	}
475 
476 	AMDPM_SMBOUTW(sc, AMDSMB_HSTADDR, slave | LSB);
477 	AMDPM_SMBOUTB(sc, AMDSMB_HSTCMD, cmd);
478 	l = AMDPM_SMBINW(sc, AMDSMB_GLOBAL_ENABLE);
479 	AMDPM_SMBOUTW(sc, AMDSMB_GLOBAL_ENABLE, (l & 0xfff8) | AMDSMB_GE_CYC_BDATA | AMDSMB_GE_HOST_STC);
480 
481 	if ((error = amdpm_wait(sc)) == SMB_ENOERR)
482 		*byte = AMDPM_SMBINW(sc, AMDSMB_HSTDATA);
483 
484 	AMDPM_DEBUG(printf("amdpm: READB from 0x%x, cmd=0x%x, byte=0x%x, error=0x%x\n", slave, cmd, *byte, error));
485 	AMDPM_UNLOCK(sc);
486 
487 	return (error);
488 }
489 
490 static int
491 amdpm_writew(device_t dev, u_char slave, char cmd, short word)
492 {
493 	struct amdpm_softc *sc = (struct amdpm_softc *)device_get_softc(dev);
494 	int error;
495 	u_short l;
496 
497 	AMDPM_LOCK(sc);
498 	amdpm_clear(sc);
499 	if (!amdpm_idle(sc)) {
500 		AMDPM_UNLOCK(sc);
501 		return (SMB_EBUSY);
502 	}
503 
504 	AMDPM_SMBOUTW(sc, AMDSMB_HSTADDR, slave & ~LSB);
505 	AMDPM_SMBOUTW(sc, AMDSMB_HSTDATA, word);
506 	AMDPM_SMBOUTB(sc, AMDSMB_HSTCMD, cmd);
507 	l = AMDPM_SMBINW(sc, AMDSMB_GLOBAL_ENABLE);
508 	AMDPM_SMBOUTW(sc, AMDSMB_GLOBAL_ENABLE, (l & 0xfff8) | AMDSMB_GE_CYC_WDATA | AMDSMB_GE_HOST_STC);
509 
510 	error = amdpm_wait(sc);
511 
512 	AMDPM_DEBUG(printf("amdpm: WRITEW to 0x%x, cmd=0x%x, word=0x%x, error=0x%x\n", slave, cmd, word, error));
513 	AMDPM_UNLOCK(sc);
514 
515 	return (error);
516 }
517 
518 static int
519 amdpm_readw(device_t dev, u_char slave, char cmd, short *word)
520 {
521 	struct amdpm_softc *sc = (struct amdpm_softc *)device_get_softc(dev);
522 	int error;
523 	u_short l;
524 
525 	AMDPM_LOCK(sc);
526 	amdpm_clear(sc);
527 	if (!amdpm_idle(sc)) {
528 		AMDPM_UNLOCK(sc);
529 		return (SMB_EBUSY);
530 	}
531 
532 	AMDPM_SMBOUTW(sc, AMDSMB_HSTADDR, slave | LSB);
533 	AMDPM_SMBOUTB(sc, AMDSMB_HSTCMD, cmd);
534 	l = AMDPM_SMBINW(sc, AMDSMB_GLOBAL_ENABLE);
535 	AMDPM_SMBOUTW(sc, AMDSMB_GLOBAL_ENABLE, (l & 0xfff8) | AMDSMB_GE_CYC_WDATA | AMDSMB_GE_HOST_STC);
536 
537 	if ((error = amdpm_wait(sc)) == SMB_ENOERR)
538 		*word = AMDPM_SMBINW(sc, AMDSMB_HSTDATA);
539 
540 	AMDPM_DEBUG(printf("amdpm: READW from 0x%x, cmd=0x%x, word=0x%x, error=0x%x\n", slave, cmd, *word, error));
541 	AMDPM_UNLOCK(sc);
542 
543 	return (error);
544 }
545 
546 static int
547 amdpm_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf)
548 {
549 	struct amdpm_softc *sc = (struct amdpm_softc *)device_get_softc(dev);
550 	u_char i;
551 	int error;
552 	u_short l;
553 
554 	if (count < 1 || count > 32)
555 		return (SMB_EINVAL);
556 
557 	AMDPM_LOCK(sc);
558 	amdpm_clear(sc);
559 	if (!amdpm_idle(sc)) {
560 		AMDPM_UNLOCK(sc);
561 		return (SMB_EBUSY);
562 	}
563 
564 	AMDPM_SMBOUTW(sc, AMDSMB_HSTADDR, slave & ~LSB);
565 
566 	/*
567 	 * Do we have to reset the internal 32-byte buffer?
568 	 * Can't see how to do this from the data sheet.
569 	 */
570 	AMDPM_SMBOUTW(sc, AMDSMB_HSTDATA, count);
571 
572 	/* Fill the 32-byte internal buffer */
573 	for (i = 0; i < count; i++) {
574 		AMDPM_SMBOUTB(sc, AMDSMB_HSTDFIFO, buf[i]);
575 		DELAY(2);
576 	}
577 	AMDPM_SMBOUTB(sc, AMDSMB_HSTCMD, cmd);
578 	l = AMDPM_SMBINW(sc, AMDSMB_GLOBAL_ENABLE);
579 	AMDPM_SMBOUTW(sc, AMDSMB_GLOBAL_ENABLE,
580 	    (l & 0xfff8) | AMDSMB_GE_CYC_BLOCK | AMDSMB_GE_HOST_STC);
581 
582 	error = amdpm_wait(sc);
583 
584 	AMDPM_DEBUG(printf("amdpm: WRITEBLK to 0x%x, count=0x%x, cmd=0x%x, error=0x%x", slave, count, cmd, error));
585 	AMDPM_UNLOCK(sc);
586 
587 	return (error);
588 }
589 
590 static int
591 amdpm_bread(device_t dev, u_char slave, char cmd, u_char *count, char *buf)
592 {
593 	struct amdpm_softc *sc = (struct amdpm_softc *)device_get_softc(dev);
594 	u_char data, len, i;
595 	int error;
596 	u_short l;
597 
598 	if (*count < 1 || *count > 32)
599 		return (SMB_EINVAL);
600 
601 	AMDPM_LOCK(sc);
602 	amdpm_clear(sc);
603 	if (!amdpm_idle(sc)) {
604 		AMDPM_UNLOCK(sc);
605 		return (SMB_EBUSY);
606 	}
607 
608 	AMDPM_SMBOUTW(sc, AMDSMB_HSTADDR, slave | LSB);
609 
610 	AMDPM_SMBOUTB(sc, AMDSMB_HSTCMD, cmd);
611 
612 	l = AMDPM_SMBINW(sc, AMDSMB_GLOBAL_ENABLE);
613 	AMDPM_SMBOUTW(sc, AMDSMB_GLOBAL_ENABLE,
614 	    (l & 0xfff8) | AMDSMB_GE_CYC_BLOCK | AMDSMB_GE_HOST_STC);
615 
616 	if ((error = amdpm_wait(sc)) != SMB_ENOERR)
617 		goto error;
618 
619 	len = AMDPM_SMBINW(sc, AMDSMB_HSTDATA);
620 
621 	/* Read the 32-byte internal buffer */
622 	for (i = 0; i < len; i++) {
623 		data = AMDPM_SMBINB(sc, AMDSMB_HSTDFIFO);
624 		if (i < *count)
625 			buf[i] = data;
626 		DELAY(2);
627 	}
628 	*count = len;
629 
630 error:
631 	AMDPM_DEBUG(printf("amdpm: READBLK to 0x%x, count=0x%x, cmd=0x%x, error=0x%x", slave, *count, cmd, error));
632 	AMDPM_UNLOCK(sc);
633 
634 	return (error);
635 }
636 
637 static devclass_t amdpm_devclass;
638 
639 static device_method_t amdpm_methods[] = {
640 	/* Device interface */
641 	DEVMETHOD(device_probe,		amdpm_probe),
642 	DEVMETHOD(device_attach,	amdpm_attach),
643 	DEVMETHOD(device_detach,	amdpm_detach),
644 
645 	/* SMBus interface */
646 	DEVMETHOD(smbus_callback,	amdpm_callback),
647 	DEVMETHOD(smbus_quick,		amdpm_quick),
648 	DEVMETHOD(smbus_sendb,		amdpm_sendb),
649 	DEVMETHOD(smbus_recvb,		amdpm_recvb),
650 	DEVMETHOD(smbus_writeb,		amdpm_writeb),
651 	DEVMETHOD(smbus_readb,		amdpm_readb),
652 	DEVMETHOD(smbus_writew,		amdpm_writew),
653 	DEVMETHOD(smbus_readw,		amdpm_readw),
654 	DEVMETHOD(smbus_bwrite,		amdpm_bwrite),
655 	DEVMETHOD(smbus_bread,		amdpm_bread),
656 
657 	{ 0, 0 }
658 };
659 
660 static driver_t amdpm_driver = {
661 	"amdpm",
662 	amdpm_methods,
663 	sizeof(struct amdpm_softc),
664 };
665 
666 DRIVER_MODULE(amdpm, pci, amdpm_driver, amdpm_devclass, 0, 0);
667 DRIVER_MODULE(smbus, amdpm, smbus_driver, smbus_devclass, 0, 0);
668 
669 MODULE_DEPEND(amdpm, pci, 1, 1, 1);
670 MODULE_DEPEND(amdpm, smbus, SMBUS_MINVER, SMBUS_PREFVER, SMBUS_MAXVER);
671 MODULE_VERSION(amdpm, 1);
672