xref: /openbsd-src/sys/dev/pci/amdpm.c (revision 352785485b55abf2a4a8158a43cb0757db5ed9ff)
1 /*	$OpenBSD: amdpm.c,v 1.30 2013/07/03 15:34:48 sf Exp $	*/
2 
3 /*
4  * Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 /*-
20  * Copyright (c) 2002 The NetBSD Foundation, Inc.
21  * All rights reserved.
22  *
23  * This code is derived from software contributed to The NetBSD Foundation
24  * by Enami Tsugutomo.
25  *
26  * Redistribution and use in source and binary forms, with or without
27  * modification, are permitted provided that the following conditions
28  * are met:
29  * 1. Redistributions of source code must retain the above copyright
30  *    notice, this list of conditions and the following disclaimer.
31  * 2. Redistributions in binary form must reproduce the above copyright
32  *    notice, this list of conditions and the following disclaimer in the
33  *    documentation and/or other materials provided with the distribution.
34  *
35  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
36  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
37  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
38  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
39  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
40  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
41  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
42  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
43  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
44  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
45  * POSSIBILITY OF SUCH DAMAGE.
46  */
47 
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/device.h>
51 #include <sys/kernel.h>
52 #include <sys/rwlock.h>
53 #include <sys/timeout.h>
54 #include <sys/timetc.h>
55 
56 #include <machine/bus.h>
57 
58 #include <dev/pci/pcivar.h>
59 #include <dev/pci/pcireg.h>
60 #include <dev/pci/pcidevs.h>
61 
62 #include <dev/rndvar.h>
63 #include <dev/i2c/i2cvar.h>
64 
65 #ifdef AMDPM_DEBUG
66 #define DPRINTF(x...) printf(x)
67 #else
68 #define DPRINTF(x...)
69 #endif
70 
71 #define AMDPM_SMBUS_DELAY	100
72 #define AMDPM_SMBUS_TIMEOUT	1
73 
74 u_int amdpm_get_timecount(struct timecounter *tc);
75 
76 #ifndef AMDPM_FREQUENCY
77 #define AMDPM_FREQUENCY 3579545
78 #endif
79 
80 static struct timecounter amdpm_timecounter = {
81 	amdpm_get_timecount,	/* get_timecount */
82 	0,			/* no poll_pps */
83 	0xffffff,		/* counter_mask */
84 	AMDPM_FREQUENCY,	/* frequency */
85 	"AMDPM",		/* name */
86 	1000			/* quality */
87 };
88 
89 #define	AMDPM_CONFREG	0x40
90 
91 /* 0x40: General Configuration 1 Register */
92 #define	AMDPM_RNGEN	0x00000080	/* random number generator enable */
93 #define	AMDPM_STOPTMR	0x00000040	/* stop free-running timer */
94 
95 /* 0x41: General Configuration 2 Register */
96 #define	AMDPM_PMIOEN	0x00008000	/* system management IO space enable */
97 #define	AMDPM_TMRRST	0x00004000	/* reset free-running timer */
98 #define	AMDPM_TMR32	0x00000800	/* extended (32 bit) timer enable */
99 
100 /* 0x42: SCI Interrupt Configuration Register */
101 /* 0x43: Previous Power State Register */
102 
103 #define	AMDPM_PMPTR	0x58		/* PMxx System Management IO space
104 					   Pointer */
105 #define NFPM_PMPTR	0x14		/* nForce System Management IO space
106 					   POinter */
107 #define	AMDPM_PMBASE(x)	((x) & 0xff00)	/* PMxx base address */
108 #define	AMDPM_PMSIZE	256		/* PMxx space size */
109 
110 /* Registers in PMxx space */
111 #define	AMDPM_TMR	0x08		/* 24/32 bit timer register */
112 
113 #define	AMDPM_RNGDATA	0xf0		/* 32 bit random data register */
114 #define	AMDPM_RNGSTAT	0xf4		/* RNG status register */
115 #define	AMDPM_RNGDONE	0x00000001	/* Random number generation complete */
116 
117 #define AMDPM_SMB_REGS  0xe0		/* offset of SMB register space */
118 #define AMDPM_SMB_SIZE  0xf		/* size of SMB register space */
119 #define AMDPM_SMBSTAT	0x0		/* SMBus status */
120 #define AMDPM_SMBSTAT_ABRT	(1 << 0)	/* transfer abort */
121 #define AMDPM_SMBSTAT_COL	(1 << 1)	/* collision */
122 #define AMDPM_SMBSTAT_PRERR	(1 << 2)	/* protocol error */
123 #define AMDPM_SMBSTAT_HBSY	(1 << 3)	/* host controller busy */
124 #define AMDPM_SMBSTAT_CYC	(1 << 4)	/* cycle complete */
125 #define AMDPM_SMBSTAT_TO	(1 << 5)	/* timeout */
126 #define AMDPM_SMBSTAT_SNP	(1 << 8)	/* snoop address match */
127 #define AMDPM_SMBSTAT_SLV	(1 << 9)	/* slave address match */
128 #define AMDPM_SMBSTAT_SMBA	(1 << 10)	/* SMBALERT# asserted */
129 #define AMDPM_SMBSTAT_BSY	(1 << 11)	/* bus busy */
130 #define AMDPM_SMBSTAT_BITS	"\020\001ABRT\002COL\003PRERR\004HBSY\005CYC\006TO\011SNP\012SLV\013SMBA\014BSY"
131 #define AMDPM_SMBCTL	0x2		/* SMBus control */
132 #define AMDPM_SMBCTL_CMD_QUICK	0		/* QUICK command */
133 #define AMDPM_SMBCTL_CMD_BYTE	1		/* BYTE command */
134 #define AMDPM_SMBCTL_CMD_BDATA	2		/* BYTE DATA command */
135 #define AMDPM_SMBCTL_CMD_WDATA	3		/* WORD DATA command */
136 #define AMDPM_SMBCTL_CMD_PCALL	4		/* PROCESS CALL command */
137 #define AMDPM_SMBCTL_CMD_BLOCK	5		/* BLOCK command */
138 #define AMDPM_SMBCTL_START	(1 << 3)	/* start transfer */
139 #define AMDPM_SMBCTL_CYCEN	(1 << 4)	/* intr on cycle complete */
140 #define AMDPM_SMBCTL_ABORT	(1 << 5)	/* abort transfer */
141 #define AMDPM_SMBCTL_SNPEN	(1 << 8)	/* intr on snoop addr match */
142 #define AMDPM_SMBCTL_SLVEN	(1 << 9)	/* intr on slave addr match */
143 #define AMDPM_SMBCTL_SMBAEN	(1 << 10)	/* intr on SMBALERT# */
144 #define AMDPM_SMBADDR	0x4		/* SMBus address */
145 #define AMDPM_SMBADDR_READ	(1 << 0)	/* read direction */
146 #define AMDPM_SMBADDR_ADDR(x)	(((x) & 0x7f) << 1) /* 7-bit address */
147 #define AMDPM_SMBDATA	0x6		/* SMBus data */
148 #define AMDPM_SMBCMD	0x8		/* SMBus command */
149 
150 
151 struct amdpm_softc {
152 	struct device sc_dev;
153 
154 	pci_chipset_tag_t sc_pc;
155 	pcitag_t sc_tag;
156 
157 	bus_space_tag_t sc_iot;
158 	bus_space_handle_t sc_ioh;		/* PMxx space */
159 	bus_space_handle_t sc_i2c_ioh;		/* I2C space */
160 	int sc_poll;
161 
162 	struct timeout sc_rnd_ch;
163 
164 	struct i2c_controller sc_i2c_tag;
165 	struct rwlock sc_i2c_lock;
166 	struct {
167 		i2c_op_t op;
168 		void *buf;
169 		size_t len;
170 		int flags;
171 		volatile int error;
172 	} sc_i2c_xfer;
173 };
174 
175 int	amdpm_match(struct device *, void *, void *);
176 void	amdpm_attach(struct device *, struct device *, void *);
177 int	amdpm_activate(struct device *, int);
178 void	amdpm_rnd_callout(void *);
179 
180 int	amdpm_i2c_acquire_bus(void *, int);
181 void	amdpm_i2c_release_bus(void *, int);
182 int	amdpm_i2c_exec(void *, i2c_op_t, i2c_addr_t, const void *, size_t,
183 	    void *, size_t, int);
184 
185 int	amdpm_intr(void *);
186 
187 struct cfattach amdpm_ca = {
188 	sizeof(struct amdpm_softc), amdpm_match, amdpm_attach,
189 	NULL, amdpm_activate
190 };
191 
192 struct cfdriver amdpm_cd = {
193 	NULL, "amdpm", DV_DULL
194 };
195 
196 const struct pci_matchid amdpm_ids[] = {
197 	{ PCI_VENDOR_AMD, PCI_PRODUCT_AMD_PBC756_PMC },
198 	{ PCI_VENDOR_AMD, PCI_PRODUCT_AMD_766_PMC },
199 	{ PCI_VENDOR_AMD, PCI_PRODUCT_AMD_PBC768_PMC },
200 	{ PCI_VENDOR_AMD, PCI_PRODUCT_AMD_8111_PMC },
201 	{ PCI_VENDOR_NVIDIA, PCI_PRODUCT_NVIDIA_NFORCE_SMB }
202 };
203 
204 int
205 amdpm_match(struct device *parent, void *match, void *aux)
206 {
207 	return (pci_matchbyid(aux, amdpm_ids,
208 	    sizeof(amdpm_ids) / sizeof(amdpm_ids[0])));
209 }
210 
211 void
212 amdpm_attach(struct device *parent, struct device *self, void *aux)
213 {
214 	struct amdpm_softc *sc = (struct amdpm_softc *) self;
215 	struct pci_attach_args *pa = aux;
216 	struct i2cbus_attach_args iba;
217 	pcireg_t cfg_reg, reg;
218 	int i;
219 
220 	sc->sc_pc = pa->pa_pc;
221 	sc->sc_tag = pa->pa_tag;
222 	sc->sc_iot = pa->pa_iot;
223 	sc->sc_poll = 1; /* XXX */
224 
225 
226 	if (PCI_VENDOR(pa->pa_id) == PCI_VENDOR_AMD)  {
227 		cfg_reg = pci_conf_read(pa->pa_pc, pa->pa_tag, AMDPM_CONFREG);
228 		if ((cfg_reg & AMDPM_PMIOEN) == 0) {
229 			printf(": PMxx space isn't enabled\n");
230 			return;
231 		}
232 
233 		reg = pci_conf_read(pa->pa_pc, pa->pa_tag, AMDPM_PMPTR);
234 		if (AMDPM_PMBASE(reg) == 0 ||
235 		    bus_space_map(sc->sc_iot, AMDPM_PMBASE(reg), AMDPM_PMSIZE,
236 		    0, &sc->sc_ioh)) {
237 			printf("\n");
238 			return;
239 		}
240 		if (bus_space_subregion(sc->sc_iot, sc->sc_ioh, AMDPM_SMB_REGS,
241 		    AMDPM_SMB_SIZE, &sc->sc_i2c_ioh)) {
242 			printf(": failed to map I2C subregion\n");
243 			return;
244 		}
245 
246 		if ((cfg_reg & AMDPM_TMRRST) == 0 &&
247 		    (cfg_reg & AMDPM_STOPTMR) == 0 &&
248 		    (PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_AMD_PBC768_PMC ||
249 		    PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_AMD_8111_PMC)) {
250 			printf(": %d-bit timer at %lluHz",
251 			    (cfg_reg & AMDPM_TMR32) ? 32 : 24,
252 			    amdpm_timecounter.tc_frequency);
253 
254 			amdpm_timecounter.tc_priv = sc;
255 			if (cfg_reg & AMDPM_TMR32)
256 				amdpm_timecounter.tc_counter_mask = 0xffffffffu;
257 			tc_init(&amdpm_timecounter);
258 		}
259 		if (PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_AMD_PBC768_PMC ||
260 		    PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_AMD_8111_PMC) {
261 			if ((cfg_reg & AMDPM_RNGEN) ==0) {
262 				pci_conf_write(pa->pa_pc, pa->pa_tag,
263 				    AMDPM_CONFREG, cfg_reg | AMDPM_RNGEN);
264 				cfg_reg = pci_conf_read(pa->pa_pc, pa->pa_tag,
265 				    AMDPM_CONFREG);
266 			}
267 			if (cfg_reg & AMDPM_RNGEN) {
268 			/* Check to see if we can read data from the RNG. */
269 				(void) bus_space_read_4(sc->sc_iot, sc->sc_ioh,
270 				    AMDPM_RNGDATA);
271 				for (i = 1000; i--; ) {
272 					if (bus_space_read_1(sc->sc_iot,
273 					    sc->sc_ioh, AMDPM_RNGSTAT) &
274 					    AMDPM_RNGDONE)
275 						break;
276 					DELAY(10);
277 				}
278 				if (bus_space_read_1(sc->sc_iot, sc->sc_ioh,
279 				    AMDPM_RNGSTAT) & AMDPM_RNGDONE) {
280 					printf(": rng active");
281 					timeout_set(&sc->sc_rnd_ch,
282 					    amdpm_rnd_callout, sc);
283 					amdpm_rnd_callout(sc);
284 				}
285 			}
286 		}
287 	} else if (PCI_VENDOR(pa->pa_id) == PCI_VENDOR_NVIDIA) {
288 		reg = pci_conf_read(pa->pa_pc, pa->pa_tag, NFPM_PMPTR);
289 		if (AMDPM_PMBASE(reg) == 0 ||
290 		    bus_space_map(sc->sc_iot, AMDPM_PMBASE(reg), AMDPM_SMB_SIZE, 0,
291 		    &sc->sc_i2c_ioh)) {
292 			printf(": failed to map I2C subregion\n");
293 			return;
294 		}
295 	}
296 	printf("\n");
297 
298 	/* Attach I2C bus */
299 	rw_init(&sc->sc_i2c_lock, "iiclk");
300 	sc->sc_i2c_tag.ic_cookie = sc;
301 	sc->sc_i2c_tag.ic_acquire_bus = amdpm_i2c_acquire_bus;
302 	sc->sc_i2c_tag.ic_release_bus = amdpm_i2c_release_bus;
303 	sc->sc_i2c_tag.ic_exec = amdpm_i2c_exec;
304 
305 	bzero(&iba, sizeof(iba));
306 	iba.iba_name = "iic";
307 	iba.iba_tag = &sc->sc_i2c_tag;
308 	config_found(self, &iba, iicbus_print);
309 }
310 
311 int
312 amdpm_activate(struct device *self, int act)
313 {
314 	struct amdpm_softc *sc = (struct amdpm_softc *)self;
315 	int ret = 0;
316 
317 	switch (act) {
318 	case DVACT_QUIESCE:
319 		ret = config_activate_children(self, act);
320 		break;
321 	case DVACT_SUSPEND:
322 		ret = config_activate_children(self, act);
323 		break;
324 	case DVACT_RESUME:
325 		if (timeout_initialized(&sc->sc_rnd_ch)) {
326 			pcireg_t cfg_reg;
327 
328 			/* Restart the AMD PBC768_PMC/8111_PMC RNG */
329 			cfg_reg = pci_conf_read(sc->sc_pc, sc->sc_tag,
330 			    AMDPM_CONFREG);
331 			pci_conf_write(sc->sc_pc, sc->sc_tag,
332 			    AMDPM_CONFREG, cfg_reg | AMDPM_RNGEN);
333 
334 		}
335 		ret = config_activate_children(self, act);
336 		break;
337 	case DVACT_POWERDOWN:
338 		ret = config_activate_children(self, act);
339 		break;
340 	}
341 	return (ret);
342 }
343 
344 void
345 amdpm_rnd_callout(void *v)
346 {
347 	struct amdpm_softc *sc = v;
348 	u_int32_t reg;
349 
350 	if ((bus_space_read_4(sc->sc_iot, sc->sc_ioh, AMDPM_RNGSTAT) &
351 	    AMDPM_RNGDONE) != 0) {
352 		reg = bus_space_read_4(sc->sc_iot, sc->sc_ioh, AMDPM_RNGDATA);
353 		add_true_randomness(reg);
354 	}
355 	timeout_add(&sc->sc_rnd_ch, 1);
356 }
357 
358 u_int
359 amdpm_get_timecount(struct timecounter *tc)
360 {
361 	struct amdpm_softc *sc = tc->tc_priv;
362 	u_int u2;
363 #if 0
364 	u_int u1, u3;
365 #endif
366 
367 	u2 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, AMDPM_TMR);
368 #if 0
369 	u3 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, AMDPM_TMR);
370 	do {
371 		u1 = u2;
372 		u2 = u3;
373 		u3 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, AMDPM_TMR);
374 	} while (u1 > u2 || u2 > u3);
375 #endif
376 	return (u2);
377 }
378 
379 int
380 amdpm_i2c_acquire_bus(void *cookie, int flags)
381 {
382 	struct amdpm_softc *sc = cookie;
383 
384 	if (cold || sc->sc_poll || (flags & I2C_F_POLL))
385 		return (0);
386 
387 	return (rw_enter(&sc->sc_i2c_lock, RW_WRITE | RW_INTR));
388 }
389 
390 void
391 amdpm_i2c_release_bus(void *cookie, int flags)
392 {
393 	struct amdpm_softc *sc = cookie;
394 
395 	if (cold || sc->sc_poll || (flags & I2C_F_POLL))
396 		return;
397 
398 	rw_exit(&sc->sc_i2c_lock);
399 }
400 
401 int
402 amdpm_i2c_exec(void *cookie, i2c_op_t op, i2c_addr_t addr,
403     const void *cmdbuf, size_t cmdlen, void *buf, size_t len, int flags)
404 {
405 	struct amdpm_softc *sc = cookie;
406 	u_int8_t *b;
407 	u_int16_t st, ctl, data;
408 	int retries;
409 
410 	DPRINTF("%s: exec: op %d, addr 0x%02x, cmdlen %d, len %d, "
411 	    "flags 0x%02x\n", sc->sc_dev.dv_xname, op, addr, cmdlen,
412 	    len, flags);
413 
414 	/* Wait for bus to be idle */
415 	for (retries = 100; retries > 0; retries--) {
416 		st = bus_space_read_2(sc->sc_iot, sc->sc_i2c_ioh, AMDPM_SMBSTAT);
417 		if (!(st & AMDPM_SMBSTAT_BSY))
418 			break;
419 		DELAY(AMDPM_SMBUS_DELAY);
420 	}
421 	DPRINTF("%s: exec: st 0x%b\n", sc->sc_dev.dv_xname, st,
422 	    AMDPM_SMBSTAT_BITS);
423 	if (st & AMDPM_SMBSTAT_BSY)
424 		return (1);
425 
426 	if (cold || sc->sc_poll)
427 		flags |= I2C_F_POLL;
428 
429 	if (!I2C_OP_STOP_P(op) || cmdlen > 1 || len > 2)
430 		return (1);
431 
432 	/* Setup transfer */
433 	sc->sc_i2c_xfer.op = op;
434 	sc->sc_i2c_xfer.buf = buf;
435 	sc->sc_i2c_xfer.len = len;
436 	sc->sc_i2c_xfer.flags = flags;
437 	sc->sc_i2c_xfer.error = 0;
438 
439 	/* Set slave address and transfer direction */
440 	bus_space_write_2(sc->sc_iot, sc->sc_i2c_ioh, AMDPM_SMBADDR,
441 	    AMDPM_SMBADDR_ADDR(addr) |
442 	    (I2C_OP_READ_P(op) ? AMDPM_SMBADDR_READ : 0));
443 
444 	b = (void *)cmdbuf;
445 	if (cmdlen > 0)
446 		/* Set command byte */
447 		bus_space_write_1(sc->sc_iot, sc->sc_i2c_ioh, AMDPM_SMBCMD, b[0]);
448 
449 	if (I2C_OP_WRITE_P(op)) {
450 		/* Write data */
451 		data = 0;
452 		b = buf;
453 		if (len > 0)
454 			data = b[0];
455 		if (len > 1)
456 			data |= ((u_int16_t)b[1] << 8);
457 		if (len > 0)
458 			bus_space_write_2(sc->sc_iot, sc->sc_i2c_ioh,
459 			    AMDPM_SMBDATA, data);
460 	}
461 
462 	/* Set SMBus command */
463 	if (len == 0)
464 		ctl = AMDPM_SMBCTL_CMD_BYTE;
465 	else if (len == 1)
466 		ctl = AMDPM_SMBCTL_CMD_BDATA;
467 	else if (len == 2)
468 		ctl = AMDPM_SMBCTL_CMD_WDATA;
469 	else
470 		panic("%s: unexpected len %zd", __func__, len);
471 
472 	if ((flags & I2C_F_POLL) == 0)
473 		ctl |= AMDPM_SMBCTL_CYCEN;
474 
475 	/* Start transaction */
476 	ctl |= AMDPM_SMBCTL_START;
477 	bus_space_write_2(sc->sc_iot, sc->sc_i2c_ioh, AMDPM_SMBCTL, ctl);
478 
479 	if (flags & I2C_F_POLL) {
480 		/* Poll for completion */
481 		DELAY(AMDPM_SMBUS_DELAY);
482 		for (retries = 1000; retries > 0; retries--) {
483 			st = bus_space_read_2(sc->sc_iot, sc->sc_i2c_ioh,
484 			    AMDPM_SMBSTAT);
485 			if ((st & AMDPM_SMBSTAT_HBSY) == 0)
486 				break;
487 			DELAY(AMDPM_SMBUS_DELAY);
488 		}
489 		if (st & AMDPM_SMBSTAT_HBSY)
490 			goto timeout;
491 		amdpm_intr(sc);
492 	} else {
493 		/* Wait for interrupt */
494 		if (tsleep(sc, PRIBIO, "amdpm", AMDPM_SMBUS_TIMEOUT * hz))
495 			goto timeout;
496 	}
497 
498 	if (sc->sc_i2c_xfer.error)
499 		return (1);
500 
501 	return (0);
502 
503 timeout:
504 	/*
505 	 * Transfer timeout. Kill the transaction and clear status bits.
506 	 */
507 	printf("%s: exec: op %d, addr 0x%02x, cmdlen %d, len %d, "
508 	    "flags 0x%02x: timeout, status 0x%b\n",
509 	    sc->sc_dev.dv_xname, op, addr, cmdlen, len, flags,
510 	    st, AMDPM_SMBSTAT_BITS);
511 	bus_space_write_2(sc->sc_iot, sc->sc_i2c_ioh, AMDPM_SMBCTL,
512 	    AMDPM_SMBCTL_ABORT);
513 	DELAY(AMDPM_SMBUS_DELAY);
514 	st = bus_space_read_2(sc->sc_iot, sc->sc_i2c_ioh, AMDPM_SMBSTAT);
515 	if ((st & AMDPM_SMBSTAT_ABRT) == 0)
516 		printf("%s: abort failed, status 0x%b\n",
517 		    sc->sc_dev.dv_xname, st, AMDPM_SMBSTAT_BITS);
518 	bus_space_write_2(sc->sc_iot, sc->sc_i2c_ioh, AMDPM_SMBSTAT, st);
519 	return (1);
520 }
521 
522 int
523 amdpm_intr(void *arg)
524 {
525 	struct amdpm_softc *sc = arg;
526 	u_int16_t st, data;
527 	u_int8_t *b;
528 	size_t len;
529 
530 	/* Read status */
531 	st = bus_space_read_2(sc->sc_iot, sc->sc_i2c_ioh, AMDPM_SMBSTAT);
532 	if ((st & AMDPM_SMBSTAT_HBSY) != 0 || (st & (AMDPM_SMBSTAT_ABRT |
533 	    AMDPM_SMBSTAT_COL | AMDPM_SMBSTAT_PRERR | AMDPM_SMBSTAT_CYC |
534 	    AMDPM_SMBSTAT_TO | AMDPM_SMBSTAT_SNP | AMDPM_SMBSTAT_SLV |
535 	    AMDPM_SMBSTAT_SMBA)) == 0)
536 		/* Interrupt was not for us */
537 		return (0);
538 
539 	DPRINTF("%s: intr: st 0x%b\n", sc->sc_dev.dv_xname, st,
540 	    AMDPM_SMBSTAT_BITS);
541 
542 	/* Clear status bits */
543 	bus_space_write_2(sc->sc_iot, sc->sc_i2c_ioh, AMDPM_SMBSTAT, st);
544 
545 	/* Check for errors */
546 	if (st & (AMDPM_SMBSTAT_COL | AMDPM_SMBSTAT_PRERR |
547 	    AMDPM_SMBSTAT_TO)) {
548 		sc->sc_i2c_xfer.error = 1;
549 		goto done;
550 	}
551 
552 	if (st & AMDPM_SMBSTAT_CYC) {
553 		if (I2C_OP_WRITE_P(sc->sc_i2c_xfer.op))
554 			goto done;
555 
556 		/* Read data */
557 		b = sc->sc_i2c_xfer.buf;
558 		len = sc->sc_i2c_xfer.len;
559 		if (len > 0) {
560 			data = bus_space_read_2(sc->sc_iot, sc->sc_i2c_ioh,
561 			    AMDPM_SMBDATA);
562 			b[0] = data & 0xff;
563 		}
564 		if (len > 1)
565 			b[1] = (data >> 8) & 0xff;
566 	}
567 
568 done:
569 	if ((sc->sc_i2c_xfer.flags & I2C_F_POLL) == 0)
570 		wakeup(sc);
571 	return (1);
572 }
573