xref: /netbsd-src/sys/dev/pci/piixpm.c (revision 53b02e147d4ed531c0d2a5ca9b3e8026ba3e99b5)
1 /* $NetBSD: piixpm.c,v 1.66 2021/10/12 08:36:29 andvar Exp $ */
2 /*	$OpenBSD: piixpm.c,v 1.39 2013/10/01 20:06:02 sf Exp $	*/
3 
4 /*
5  * Copyright (c) 2005, 2006 Alexander Yurchenko <grange@openbsd.org>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 /*
21  * Intel PIIX and compatible Power Management controller driver.
22  */
23 
24 #include <sys/cdefs.h>
25 __KERNEL_RCSID(0, "$NetBSD: piixpm.c,v 1.66 2021/10/12 08:36:29 andvar Exp $");
26 
27 #include <sys/param.h>
28 #include <sys/systm.h>
29 #include <sys/device.h>
30 #include <sys/kernel.h>
31 #include <sys/mutex.h>
32 #include <sys/condvar.h>
33 #include <sys/proc.h>
34 
35 #include <sys/bus.h>
36 
37 #include <dev/pci/pcidevs.h>
38 #include <dev/pci/pcireg.h>
39 #include <dev/pci/pcivar.h>
40 
41 #include <dev/pci/piixpmreg.h>
42 
43 #include <dev/i2c/i2cvar.h>
44 
45 #include <dev/ic/acpipmtimer.h>
46 
47 #ifdef PIIXPM_DEBUG
48 #define DPRINTF(x) printf x
49 #else
50 #define DPRINTF(x)
51 #endif
52 
53 #define PIIXPM_IS_CSB5(sc)						      \
54 	(PCI_VENDOR((sc)->sc_id) == PCI_VENDOR_SERVERWORKS &&		      \
55 	PCI_PRODUCT((sc)->sc_id) == PCI_PRODUCT_SERVERWORKS_CSB5)
56 #define PIIXPM_DELAY	200
57 #define PIIXPM_TIMEOUT	1
58 
59 #define PIIXPM_IS_SB800GRP(sc)						      \
60 	((PCI_VENDOR((sc)->sc_id) == PCI_VENDOR_ATI) &&			      \
61 	    ((PCI_PRODUCT((sc)->sc_id) == PCI_PRODUCT_ATI_SB600_SMB) &&	      \
62 		((sc)->sc_rev >= 0x40)))
63 
64 #define PIIXPM_IS_HUDSON(sc)						      \
65 	((PCI_VENDOR((sc)->sc_id) == PCI_VENDOR_AMD) &&			      \
66 	    (PCI_PRODUCT((sc)->sc_id) == PCI_PRODUCT_AMD_HUDSON_SMB))
67 
68 #define PIIXPM_IS_KERNCZ(sc)						      \
69 	((PCI_VENDOR((sc)->sc_id) == PCI_VENDOR_AMD) &&			      \
70 	    (PCI_PRODUCT((sc)->sc_id) == PCI_PRODUCT_AMD_KERNCZ_SMB))
71 
72 #define PIIXPM_IS_FCHGRP(sc)	(PIIXPM_IS_HUDSON(sc) || PIIXPM_IS_KERNCZ(sc))
73 
74 #define PIIX_SB800_TIMEOUT 500
75 
76 struct piixpm_smbus {
77 	int			sda;
78 	int			sda_save;
79 	struct			piixpm_softc *softc;
80 };
81 
82 struct piixpm_softc {
83 	device_t		sc_dev;
84 
85 	bus_space_tag_t		sc_iot;
86 #define	sc_pm_iot sc_iot
87 #define sc_smb_iot sc_iot
88 	bus_space_handle_t	sc_pm_ioh;
89 	bus_space_handle_t	sc_sb800_ioh;
90 	bus_space_handle_t	sc_smb_ioh;
91 	void *			sc_smb_ih;
92 	int			sc_poll;
93 	bool			sc_sb800_selen; /* Use SMBUS0SEL */
94 
95 	pci_chipset_tag_t	sc_pc;
96 	pcitag_t		sc_pcitag;
97 	pcireg_t		sc_id;
98 	pcireg_t		sc_rev;
99 
100 	int			sc_numbusses;
101 	device_t		sc_i2c_device[4];
102 	struct piixpm_smbus	sc_busses[4];
103 	struct i2c_controller	sc_i2c_tags[4];
104 
105 	kmutex_t		sc_exec_lock;
106 	kcondvar_t		sc_exec_wait;
107 
108 	struct {
109 		i2c_op_t	op;
110 		void *		buf;
111 		size_t		len;
112 		int		flags;
113 		int             error;
114 		bool            done;
115 	}			sc_i2c_xfer;
116 
117 	pcireg_t		sc_devact[2];
118 };
119 
120 static int	piixpm_match(device_t, cfdata_t, void *);
121 static void	piixpm_attach(device_t, device_t, void *);
122 static int	piixpm_rescan(device_t, const char *, const int *);
123 static void	piixpm_chdet(device_t, device_t);
124 
125 static bool	piixpm_suspend(device_t, const pmf_qual_t *);
126 static bool	piixpm_resume(device_t, const pmf_qual_t *);
127 
128 static int	piixpm_sb800_init(struct piixpm_softc *);
129 static void	piixpm_csb5_reset(void *);
130 static int	piixpm_i2c_sb800_acquire_bus(void *, int);
131 static void	piixpm_i2c_sb800_release_bus(void *, int);
132 static int	piixpm_i2c_exec(void *, i2c_op_t, i2c_addr_t, const void *,
133     size_t, void *, size_t, int);
134 
135 static int	piixpm_intr(void *);
136 
137 CFATTACH_DECL3_NEW(piixpm, sizeof(struct piixpm_softc),
138     piixpm_match, piixpm_attach, NULL, NULL, piixpm_rescan, piixpm_chdet, 0);
139 
140 static int
141 piixpm_match(device_t parent, cfdata_t match, void *aux)
142 {
143 	struct pci_attach_args *pa;
144 
145 	pa = (struct pci_attach_args *)aux;
146 	switch (PCI_VENDOR(pa->pa_id)) {
147 	case PCI_VENDOR_INTEL:
148 		switch (PCI_PRODUCT(pa->pa_id)) {
149 		case PCI_PRODUCT_INTEL_82371AB_PMC:
150 		case PCI_PRODUCT_INTEL_82440MX_PMC:
151 			return 1;
152 		}
153 		break;
154 	case PCI_VENDOR_ATI:
155 		switch (PCI_PRODUCT(pa->pa_id)) {
156 		case PCI_PRODUCT_ATI_SB200_SMB:
157 		case PCI_PRODUCT_ATI_SB300_SMB:
158 		case PCI_PRODUCT_ATI_SB400_SMB:
159 		case PCI_PRODUCT_ATI_SB600_SMB:	/* matches SB600/SB700/SB800 */
160 			return 1;
161 		}
162 		break;
163 	case PCI_VENDOR_SERVERWORKS:
164 		switch (PCI_PRODUCT(pa->pa_id)) {
165 		case PCI_PRODUCT_SERVERWORKS_OSB4:
166 		case PCI_PRODUCT_SERVERWORKS_CSB5:
167 		case PCI_PRODUCT_SERVERWORKS_CSB6:
168 		case PCI_PRODUCT_SERVERWORKS_HT1000SB:
169 		case PCI_PRODUCT_SERVERWORKS_HT1100SB:
170 			return 1;
171 		}
172 		break;
173 	case PCI_VENDOR_AMD:
174 		switch (PCI_PRODUCT(pa->pa_id)) {
175 		case PCI_PRODUCT_AMD_HUDSON_SMB:
176 		case PCI_PRODUCT_AMD_KERNCZ_SMB:
177 			return 1;
178 		}
179 		break;
180 	}
181 
182 	return 0;
183 }
184 
185 static void
186 piixpm_attach(device_t parent, device_t self, void *aux)
187 {
188 	struct piixpm_softc *sc = device_private(self);
189 	struct pci_attach_args *pa = aux;
190 	pcireg_t base, conf;
191 	pcireg_t pmmisc;
192 	pci_intr_handle_t ih;
193 	bool usesmi = false;
194 	const char *intrstr = NULL;
195 	int i;
196 	char intrbuf[PCI_INTRSTR_LEN];
197 
198 	sc->sc_dev = self;
199 	sc->sc_iot = pa->pa_iot;
200 	sc->sc_id = pa->pa_id;
201 	sc->sc_rev = PCI_REVISION(pa->pa_class);
202 	sc->sc_pc = pa->pa_pc;
203 	sc->sc_pcitag = pa->pa_tag;
204 	sc->sc_numbusses = 1;
205 
206 	pci_aprint_devinfo(pa, NULL);
207 
208 	mutex_init(&sc->sc_exec_lock, MUTEX_DEFAULT, IPL_BIO);
209 	cv_init(&sc->sc_exec_wait, device_xname(self));
210 
211 	if (!pmf_device_register(self, piixpm_suspend, piixpm_resume))
212 		aprint_error_dev(self, "couldn't establish power handler\n");
213 
214 	if ((PCI_VENDOR(pa->pa_id) != PCI_VENDOR_INTEL) ||
215 	    (PCI_PRODUCT(pa->pa_id) != PCI_PRODUCT_INTEL_82371AB_PMC))
216 		goto nopowermanagement;
217 
218 	/* check whether I/O access to PM regs is enabled */
219 	pmmisc = pci_conf_read(pa->pa_pc, pa->pa_tag, PIIX_PMREGMISC);
220 	if (!(pmmisc & 1))
221 		goto nopowermanagement;
222 
223 	/* Map I/O space */
224 	base = pci_conf_read(pa->pa_pc, pa->pa_tag, PIIX_PM_BASE);
225 	if (base == 0 || bus_space_map(sc->sc_pm_iot, PCI_MAPREG_IO_ADDR(base),
226 	    PIIX_PM_SIZE, 0, &sc->sc_pm_ioh)) {
227 		aprint_error_dev(self,
228 		    "can't map power management I/O space\n");
229 		goto nopowermanagement;
230 	}
231 
232 	/*
233 	 * Revision 0 and 1 are PIIX4, 2 is PIIX4E, 3 is PIIX4M.
234 	 * PIIX4 and PIIX4E have a bug in the timer latch, see Errata #20
235 	 * in the "Specification update" (document #297738).
236 	 */
237 	acpipmtimer_attach(self, sc->sc_pm_iot, sc->sc_pm_ioh, PIIX_PM_PMTMR,
238 	    (PCI_REVISION(pa->pa_class) < 3) ? ACPIPMT_BADLATCH : 0);
239 
240 nopowermanagement:
241 
242 	/* SB800 rev 0x40+, AMD HUDSON and newer need special initialization */
243 	if (PIIXPM_IS_FCHGRP(sc) || PIIXPM_IS_SB800GRP(sc)) {
244 		if (piixpm_sb800_init(sc) == 0) {
245 			/* Read configuration */
246 			conf = bus_space_read_1(sc->sc_iot,
247 			    sc->sc_smb_ioh, SB800_SMB_HOSTC);
248 			usesmi = ((conf & SB800_SMB_HOSTC_IRQ) == 0);
249 			goto setintr;
250 		}
251 		aprint_normal_dev(self, "SMBus initialization failed\n");
252 		return;
253 	}
254 
255 	/* Read configuration */
256 	conf = pci_conf_read(pa->pa_pc, pa->pa_tag, PIIX_SMB_HOSTC);
257 	DPRINTF(("%s: conf 0x%08x\n", device_xname(self), conf));
258 
259 	if ((conf & PIIX_SMB_HOSTC_HSTEN) == 0) {
260 		aprint_normal_dev(self, "SMBus disabled\n");
261 		return;
262 	}
263 	usesmi = (conf & PIIX_SMB_HOSTC_INTMASK) == PIIX_SMB_HOSTC_SMI;
264 
265 	/* Map I/O space */
266 	base = pci_conf_read(pa->pa_pc, pa->pa_tag, PIIX_SMB_BASE) & 0xffff;
267 	if (base == 0 ||
268 	    bus_space_map(sc->sc_smb_iot, PCI_MAPREG_IO_ADDR(base),
269 	    PIIX_SMB_SIZE, 0, &sc->sc_smb_ioh)) {
270 		aprint_error_dev(self, "can't map smbus I/O space\n");
271 		return;
272 	}
273 
274 setintr:
275 	sc->sc_poll = 1;
276 	aprint_normal_dev(self, "");
277 	if (usesmi) {
278 		/* No PCI IRQ */
279 		aprint_normal("interrupting at SMI, ");
280 	} else {
281 		if ((conf & PIIX_SMB_HOSTC_INTMASK) == PIIX_SMB_HOSTC_IRQ) {
282 			/* Install interrupt handler */
283 			if (pci_intr_map(pa, &ih) == 0) {
284 				intrstr = pci_intr_string(pa->pa_pc, ih,
285 				    intrbuf, sizeof(intrbuf));
286 				pci_intr_setattr(pa->pa_pc, &ih,
287 				    PCI_INTR_MPSAFE, true);
288 				sc->sc_smb_ih = pci_intr_establish_xname(
289 					pa->pa_pc, ih, IPL_BIO, piixpm_intr,
290 					sc, device_xname(sc->sc_dev));
291 				if (sc->sc_smb_ih != NULL) {
292 					aprint_normal("interrupting at %s",
293 					    intrstr);
294 					sc->sc_poll = 0;
295 				}
296 			}
297 		}
298 		if (sc->sc_poll)
299 			aprint_normal("polling");
300 	}
301 
302 	aprint_normal("\n");
303 
304 	for (i = 0; i < sc->sc_numbusses; i++)
305 		sc->sc_i2c_device[i] = NULL;
306 
307 	piixpm_rescan(self, NULL, NULL);
308 }
309 
310 static int
311 piixpm_iicbus_print(void *aux, const char *pnp)
312 {
313 	struct i2cbus_attach_args *iba = aux;
314 	struct i2c_controller *tag = iba->iba_tag;
315 	struct piixpm_smbus *bus = tag->ic_cookie;
316 	struct piixpm_softc *sc = bus->softc;
317 
318 	iicbus_print(aux, pnp);
319 	if (sc->sc_numbusses != 0)
320 		aprint_normal(" port %d", bus->sda);
321 
322 	return UNCONF;
323 }
324 
325 static int
326 piixpm_rescan(device_t self, const char *ifattr, const int *locators)
327 {
328 	struct piixpm_softc *sc = device_private(self);
329 	struct i2cbus_attach_args iba;
330 	int i;
331 
332 	/* Attach I2C bus */
333 
334 	for (i = 0; i < sc->sc_numbusses; i++) {
335 		struct i2c_controller *tag = &sc->sc_i2c_tags[i];
336 
337 		if (sc->sc_i2c_device[i] != NULL)
338 			continue;
339 		sc->sc_busses[i].sda = i;
340 		sc->sc_busses[i].softc = sc;
341 		iic_tag_init(tag);
342 		tag->ic_cookie = &sc->sc_busses[i];
343 		if (PIIXPM_IS_SB800GRP(sc) || PIIXPM_IS_FCHGRP(sc)) {
344 			tag->ic_acquire_bus = piixpm_i2c_sb800_acquire_bus;
345 			tag->ic_release_bus = piixpm_i2c_sb800_release_bus;
346 		} else {
347 			tag->ic_acquire_bus = NULL;
348 			tag->ic_release_bus = NULL;
349 		}
350 		tag->ic_exec = piixpm_i2c_exec;
351 		memset(&iba, 0, sizeof(iba));
352 		iba.iba_tag = tag;
353 		sc->sc_i2c_device[i] =
354 		    config_found(self, &iba, piixpm_iicbus_print, CFARGS_NONE);
355 	}
356 
357 	return 0;
358 }
359 
360 static void
361 piixpm_chdet(device_t self, device_t child)
362 {
363 	struct piixpm_softc *sc = device_private(self);
364 	int i;
365 
366 	for (i = 0; i < sc->sc_numbusses; i++) {
367 		if (sc->sc_i2c_device[i] == child) {
368 			sc->sc_i2c_device[i] = NULL;
369 			break;
370 		}
371 	}
372 }
373 
374 
375 static bool
376 piixpm_suspend(device_t dv, const pmf_qual_t *qual)
377 {
378 	struct piixpm_softc *sc = device_private(dv);
379 
380 	sc->sc_devact[0] = pci_conf_read(sc->sc_pc, sc->sc_pcitag,
381 	    PIIX_DEVACTA);
382 	sc->sc_devact[1] = pci_conf_read(sc->sc_pc, sc->sc_pcitag,
383 	    PIIX_DEVACTB);
384 
385 	return true;
386 }
387 
388 static bool
389 piixpm_resume(device_t dv, const pmf_qual_t *qual)
390 {
391 	struct piixpm_softc *sc = device_private(dv);
392 
393 	pci_conf_write(sc->sc_pc, sc->sc_pcitag, PIIX_DEVACTA,
394 	    sc->sc_devact[0]);
395 	pci_conf_write(sc->sc_pc, sc->sc_pcitag, PIIX_DEVACTB,
396 	    sc->sc_devact[1]);
397 
398 	return true;
399 }
400 
401 /*
402  * Extract SMBus base address from SB800 Power Management (PM) registers.
403  * The PM registers can be accessed either through indirect I/O (CD6/CD7) or
404  * direct mapping if AcpiMMioDecodeEn is enabled. Since this function is only
405  * called once it uses indirect I/O for simplicity.
406  */
407 static int
408 piixpm_sb800_init(struct piixpm_softc *sc)
409 {
410 	bus_space_tag_t iot = sc->sc_iot;
411 	bus_space_handle_t ioh;	/* indirect I/O handle */
412 	uint16_t val, base_addr;
413 	bool enabled;
414 
415 	if (PIIXPM_IS_KERNCZ(sc) ||
416 	    (PIIXPM_IS_HUDSON(sc) && (sc->sc_rev >= 0x1f)))
417 		sc->sc_numbusses = 2;
418 	else
419 		sc->sc_numbusses = 4;
420 
421 	/* Fetch SMB base address */
422 	if (bus_space_map(iot,
423 	    SB800_INDIRECTIO_BASE, SB800_INDIRECTIO_SIZE, 0, &ioh)) {
424 		device_printf(sc->sc_dev, "couldn't map indirect I/O space\n");
425 		return EBUSY;
426 	}
427 	if (PIIXPM_IS_FCHGRP(sc)) {
428 		bus_space_write_1(iot, ioh, SB800_INDIRECTIO_INDEX,
429 		    AMDFCH41_PM_DECODE_EN0);
430 		val = bus_space_read_1(iot, ioh, SB800_INDIRECTIO_DATA);
431 		enabled = val & AMDFCH41_SMBUS_EN;
432 		if (!enabled)
433 			return ENOENT;
434 
435 		bus_space_write_1(iot, ioh, SB800_INDIRECTIO_INDEX,
436 		    AMDFCH41_PM_DECODE_EN1);
437 		val = bus_space_read_1(iot, ioh, SB800_INDIRECTIO_DATA) << 8;
438 		base_addr = val;
439 	} else {
440 		uint8_t data;
441 
442 		bus_space_write_1(iot, ioh, SB800_INDIRECTIO_INDEX,
443 		    SB800_PM_SMBUS0EN_LO);
444 		val = bus_space_read_1(iot, ioh, SB800_INDIRECTIO_DATA);
445 		enabled = val & SB800_PM_SMBUS0EN_ENABLE;
446 		if (!enabled)
447 			return ENOENT;
448 
449 		bus_space_write_1(iot, ioh, SB800_INDIRECTIO_INDEX,
450 		    SB800_PM_SMBUS0EN_HI);
451 		val |= bus_space_read_1(iot, ioh, SB800_INDIRECTIO_DATA) << 8;
452 		base_addr = val & SB800_PM_SMBUS0EN_BADDR;
453 
454 		bus_space_write_1(iot, ioh, SB800_INDIRECTIO_INDEX,
455 		    SB800_PM_SMBUS0SELEN);
456 		data = bus_space_read_1(iot, ioh, SB800_INDIRECTIO_DATA);
457 		if ((data & SB800_PM_USE_SMBUS0SEL) != 0)
458 			sc->sc_sb800_selen = true;
459 	}
460 
461 	sc->sc_sb800_ioh = ioh;
462 	aprint_debug_dev(sc->sc_dev, "SMBus @ 0x%04x\n", base_addr);
463 
464 	if (bus_space_map(iot, PCI_MAPREG_IO_ADDR(base_addr),
465 	    SB800_SMB_SIZE, 0, &sc->sc_smb_ioh)) {
466 		aprint_error_dev(sc->sc_dev, "can't map smbus I/O space\n");
467 		return EBUSY;
468 	}
469 
470 	return 0;
471 }
472 
473 static void
474 piixpm_csb5_reset(void *arg)
475 {
476 	struct piixpm_softc *sc = arg;
477 	pcireg_t base, hostc, pmbase;
478 
479 	base = pci_conf_read(sc->sc_pc, sc->sc_pcitag, PIIX_SMB_BASE);
480 	hostc = pci_conf_read(sc->sc_pc, sc->sc_pcitag, PIIX_SMB_HOSTC);
481 
482 	pmbase = pci_conf_read(sc->sc_pc, sc->sc_pcitag, PIIX_PM_BASE);
483 	pmbase |= PIIX_PM_BASE_CSB5_RESET;
484 	pci_conf_write(sc->sc_pc, sc->sc_pcitag, PIIX_PM_BASE, pmbase);
485 	pmbase &= ~PIIX_PM_BASE_CSB5_RESET;
486 	pci_conf_write(sc->sc_pc, sc->sc_pcitag, PIIX_PM_BASE, pmbase);
487 
488 	pci_conf_write(sc->sc_pc, sc->sc_pcitag, PIIX_SMB_BASE, base);
489 	pci_conf_write(sc->sc_pc, sc->sc_pcitag, PIIX_SMB_HOSTC, hostc);
490 
491 	(void) tsleep(&sc, PRIBIO, "csb5reset", hz/2);
492 }
493 
494 static int
495 piixpm_i2c_sb800_acquire_bus(void *cookie, int flags)
496 {
497 	struct piixpm_smbus *smbus = cookie;
498 	struct piixpm_softc *sc = smbus->softc;
499 	uint8_t sctl, old_sda, index, mask, reg;
500 	int i;
501 
502 	sctl = bus_space_read_1(sc->sc_smb_iot, sc->sc_smb_ioh, PIIX_SMB_SC);
503 	for (i = 0; i < PIIX_SB800_TIMEOUT; i++) {
504 		/* Try to acquire the host semaphore */
505 		sctl &= ~PIIX_SMB_SC_SEMMASK;
506 		bus_space_write_1(sc->sc_smb_iot, sc->sc_smb_ioh, PIIX_SMB_SC,
507 		    sctl | PIIX_SMB_SC_HOSTSEM);
508 
509 		sctl = bus_space_read_1(sc->sc_smb_iot, sc->sc_smb_ioh,
510 		    PIIX_SMB_SC);
511 		if ((sctl & PIIX_SMB_SC_HOSTSEM) != 0)
512 			break;
513 
514 		delay(1000);
515 	}
516 	if (i >= PIIX_SB800_TIMEOUT) {
517 		device_printf(sc->sc_dev,
518 		    "Failed to acquire the host semaphore\n");
519 		return -1;
520 	}
521 
522 	if (PIIXPM_IS_KERNCZ(sc) ||
523 	    (PIIXPM_IS_HUDSON(sc) && (sc->sc_rev >= 0x1f))) {
524 		index = AMDFCH41_PM_PORT_INDEX;
525 		mask = AMDFCH41_SMBUS_PORTMASK;
526 	} else if (sc->sc_sb800_selen) {
527 		index = SB800_PM_SMBUS0SEL;
528 		mask = SB800_PM_SMBUS0_MASK_E;
529 	} else {
530 		index = SB800_PM_SMBUS0EN_LO;
531 		mask = SB800_PM_SMBUS0_MASK_C;
532 	}
533 
534 	bus_space_write_1(sc->sc_iot, sc->sc_sb800_ioh,
535 	    SB800_INDIRECTIO_INDEX, index);
536 	reg = bus_space_read_1(sc->sc_iot, sc->sc_sb800_ioh,
537 	    SB800_INDIRECTIO_DATA);
538 
539 	old_sda = __SHIFTOUT(reg, mask);
540 	if (smbus->sda != old_sda) {
541 		reg &= ~mask;
542 		reg |= __SHIFTIN(smbus->sda, mask);
543 		bus_space_write_1(sc->sc_iot, sc->sc_sb800_ioh,
544 		    SB800_INDIRECTIO_DATA, reg);
545 	}
546 
547 	/* Save the old port number */
548 	smbus->sda_save = old_sda;
549 
550 	return 0;
551 }
552 
553 static void
554 piixpm_i2c_sb800_release_bus(void *cookie, int flags)
555 {
556 	struct piixpm_smbus *smbus = cookie;
557 	struct piixpm_softc *sc = smbus->softc;
558 	uint8_t sctl, index, mask, reg;
559 
560 	if (PIIXPM_IS_KERNCZ(sc) ||
561 	    (PIIXPM_IS_HUDSON(sc) && (sc->sc_rev >= 0x1f))) {
562 		index = AMDFCH41_PM_PORT_INDEX;
563 		mask = AMDFCH41_SMBUS_PORTMASK;
564 	} else if (sc->sc_sb800_selen) {
565 		index = SB800_PM_SMBUS0SEL;
566 		mask = SB800_PM_SMBUS0_MASK_E;
567 	} else {
568 		index = SB800_PM_SMBUS0EN_LO;
569 		mask = SB800_PM_SMBUS0_MASK_C;
570 	}
571 
572 	bus_space_write_1(sc->sc_iot, sc->sc_sb800_ioh,
573 	    SB800_INDIRECTIO_INDEX, index);
574 	if (smbus->sda != smbus->sda_save) {
575 		/* Restore the port number */
576 		reg = bus_space_read_1(sc->sc_iot, sc->sc_sb800_ioh,
577 		    SB800_INDIRECTIO_DATA);
578 		reg &= ~mask;
579 		reg |= __SHIFTIN(smbus->sda_save, mask);
580 		bus_space_write_1(sc->sc_iot, sc->sc_sb800_ioh,
581 		    SB800_INDIRECTIO_DATA, reg);
582 	}
583 
584 	/* Release the host semaphore */
585 	sctl = bus_space_read_1(sc->sc_smb_iot, sc->sc_smb_ioh, PIIX_SMB_SC);
586 	sctl &= ~PIIX_SMB_SC_SEMMASK;
587 	bus_space_write_1(sc->sc_smb_iot, sc->sc_smb_ioh, PIIX_SMB_SC,
588 	    sctl | PIIX_SMB_SC_CLRHOSTSEM);
589 }
590 
591 static int
592 piixpm_i2c_exec(void *cookie, i2c_op_t op, i2c_addr_t addr,
593     const void *cmdbuf, size_t cmdlen, void *buf, size_t len, int flags)
594 {
595 	struct piixpm_smbus *smbus = cookie;
596 	struct piixpm_softc *sc = smbus->softc;
597 	const uint8_t *b;
598 	uint8_t ctl = 0, st;
599 	int retries;
600 
601 	DPRINTF(("%s: exec: op %d, addr 0x%02x, cmdlen %zu, len %zu, "
602 		"flags 0x%x\n",
603 		device_xname(sc->sc_dev), op, addr, cmdlen, len, flags));
604 
605 	mutex_enter(&sc->sc_exec_lock);
606 
607 	/* Clear status bits */
608 	bus_space_write_1(sc->sc_smb_iot, sc->sc_smb_ioh, PIIX_SMB_HS,
609 	    PIIX_SMB_HS_INTR | PIIX_SMB_HS_DEVERR |
610 	    PIIX_SMB_HS_BUSERR | PIIX_SMB_HS_FAILED);
611 	bus_space_barrier(sc->sc_smb_iot, sc->sc_smb_ioh, PIIX_SMB_HS, 1,
612 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
613 
614 	/* Wait for bus to be idle */
615 	for (retries = 100; retries > 0; retries--) {
616 		st = bus_space_read_1(sc->sc_smb_iot, sc->sc_smb_ioh,
617 		    PIIX_SMB_HS);
618 		if (!(st & PIIX_SMB_HS_BUSY))
619 			break;
620 		DELAY(PIIXPM_DELAY);
621 	}
622 	DPRINTF(("%s: exec: st %#x\n", device_xname(sc->sc_dev), st & 0xff));
623 	if (st & PIIX_SMB_HS_BUSY) {
624 		mutex_exit(&sc->sc_exec_lock);
625 		return (EBUSY);
626 	}
627 
628 	if (sc->sc_poll)
629 		flags |= I2C_F_POLL;
630 
631 	if (!I2C_OP_STOP_P(op) || cmdlen > 1 || len > 2 ||
632 	    (cmdlen == 0 && len > 1)) {
633 		mutex_exit(&sc->sc_exec_lock);
634 		return (EINVAL);
635 	}
636 
637 	/* Setup transfer */
638 	sc->sc_i2c_xfer.op = op;
639 	sc->sc_i2c_xfer.buf = buf;
640 	sc->sc_i2c_xfer.len = len;
641 	sc->sc_i2c_xfer.flags = flags;
642 	sc->sc_i2c_xfer.error = 0;
643 	sc->sc_i2c_xfer.done = false;
644 
645 	/* Set slave address and transfer direction */
646 	bus_space_write_1(sc->sc_smb_iot, sc->sc_smb_ioh, PIIX_SMB_TXSLVA,
647 	    PIIX_SMB_TXSLVA_ADDR(addr) |
648 	    (I2C_OP_READ_P(op) ? PIIX_SMB_TXSLVA_READ : 0));
649 
650 	b = cmdbuf;
651 	if (cmdlen > 0)
652 		/* Set command byte */
653 		bus_space_write_1(sc->sc_smb_iot, sc->sc_smb_ioh,
654 		    PIIX_SMB_HCMD, b[0]);
655 
656 	if (I2C_OP_WRITE_P(op)) {
657 		/* Write data */
658 		b = buf;
659 		if (cmdlen == 0 && len == 1)
660 			bus_space_write_1(sc->sc_smb_iot, sc->sc_smb_ioh,
661 			    PIIX_SMB_HCMD, b[0]);
662 		else if (len > 0)
663 			bus_space_write_1(sc->sc_smb_iot, sc->sc_smb_ioh,
664 			    PIIX_SMB_HD0, b[0]);
665 		if (len > 1)
666 			bus_space_write_1(sc->sc_smb_iot, sc->sc_smb_ioh,
667 			    PIIX_SMB_HD1, b[1]);
668 	}
669 
670 	/* Set SMBus command */
671 	if (cmdlen == 0) {
672 		if (len == 0)
673 			ctl = PIIX_SMB_HC_CMD_QUICK;
674 		else
675 			ctl = PIIX_SMB_HC_CMD_BYTE;
676 	} else if (len == 1)
677 		ctl = PIIX_SMB_HC_CMD_BDATA;
678 	else if (len == 2)
679 		ctl = PIIX_SMB_HC_CMD_WDATA;
680 	else
681 		panic("%s: unexpected len %zu", __func__, len);
682 
683 	if ((flags & I2C_F_POLL) == 0)
684 		ctl |= PIIX_SMB_HC_INTREN;
685 
686 	/* Start transaction */
687 	ctl |= PIIX_SMB_HC_START;
688 	bus_space_write_1(sc->sc_smb_iot, sc->sc_smb_ioh, PIIX_SMB_HC, ctl);
689 
690 	if (flags & I2C_F_POLL) {
691 		/* Poll for completion */
692 		if (PIIXPM_IS_CSB5(sc))
693 			DELAY(2*PIIXPM_DELAY);
694 		else
695 			DELAY(PIIXPM_DELAY);
696 		for (retries = 1000; retries > 0; retries--) {
697 			st = bus_space_read_1(sc->sc_smb_iot, sc->sc_smb_ioh,
698 			    PIIX_SMB_HS);
699 			if ((st & PIIX_SMB_HS_BUSY) == 0)
700 				break;
701 			DELAY(PIIXPM_DELAY);
702 		}
703 		if (st & PIIX_SMB_HS_BUSY)
704 			goto timeout;
705 		piixpm_intr(sc);
706 	} else {
707 		/* Wait for interrupt */
708 		while (! sc->sc_i2c_xfer.done) {
709 			if (cv_timedwait(&sc->sc_exec_wait, &sc->sc_exec_lock,
710 					 PIIXPM_TIMEOUT * hz))
711 				goto timeout;
712 		}
713 	}
714 
715 	int error = sc->sc_i2c_xfer.error;
716 	mutex_exit(&sc->sc_exec_lock);
717 
718 	return (error);
719 
720 timeout:
721 	/*
722 	 * Transfer timeout. Kill the transaction and clear status bits.
723 	 */
724 	aprint_error_dev(sc->sc_dev, "timeout, status 0x%x\n", st);
725 	bus_space_write_1(sc->sc_smb_iot, sc->sc_smb_ioh, PIIX_SMB_HC,
726 	    PIIX_SMB_HC_KILL);
727 	DELAY(PIIXPM_DELAY);
728 	st = bus_space_read_1(sc->sc_smb_iot, sc->sc_smb_ioh, PIIX_SMB_HS);
729 	if ((st & PIIX_SMB_HS_FAILED) == 0)
730 		aprint_error_dev(sc->sc_dev,
731 		    "transaction abort failed, status 0x%x\n", st);
732 	bus_space_write_1(sc->sc_smb_iot, sc->sc_smb_ioh, PIIX_SMB_HS, st);
733 	/*
734 	 * CSB5 needs hard reset to unlock the smbus after timeout.
735 	 */
736 	if (PIIXPM_IS_CSB5(sc))
737 		piixpm_csb5_reset(sc);
738 	mutex_exit(&sc->sc_exec_lock);
739 	return (ETIMEDOUT);
740 }
741 
742 static int
743 piixpm_intr(void *arg)
744 {
745 	struct piixpm_softc *sc = arg;
746 	uint8_t st;
747 	uint8_t *b;
748 	size_t len;
749 
750 	/* Read status */
751 	st = bus_space_read_1(sc->sc_smb_iot, sc->sc_smb_ioh, PIIX_SMB_HS);
752 	if ((st & PIIX_SMB_HS_BUSY) != 0 || (st & (PIIX_SMB_HS_INTR |
753 	    PIIX_SMB_HS_DEVERR | PIIX_SMB_HS_BUSERR |
754 	    PIIX_SMB_HS_FAILED)) == 0)
755 		/* Interrupt was not for us */
756 		return (0);
757 
758 	DPRINTF(("%s: intr st %#x\n", device_xname(sc->sc_dev), st & 0xff));
759 
760 	if ((sc->sc_i2c_xfer.flags & I2C_F_POLL) == 0)
761 		mutex_enter(&sc->sc_exec_lock);
762 
763 	/* Clear status bits */
764 	bus_space_write_1(sc->sc_smb_iot, sc->sc_smb_ioh, PIIX_SMB_HS, st);
765 
766 	/* Check for errors */
767 	if (st & (PIIX_SMB_HS_DEVERR | PIIX_SMB_HS_BUSERR |
768 	    PIIX_SMB_HS_FAILED)) {
769 		sc->sc_i2c_xfer.error = EIO;
770 		goto done;
771 	}
772 
773 	if (st & PIIX_SMB_HS_INTR) {
774 		if (I2C_OP_WRITE_P(sc->sc_i2c_xfer.op))
775 			goto done;
776 
777 		/* Read data */
778 		b = sc->sc_i2c_xfer.buf;
779 		len = sc->sc_i2c_xfer.len;
780 		if (len > 0)
781 			b[0] = bus_space_read_1(sc->sc_smb_iot, sc->sc_smb_ioh,
782 			    PIIX_SMB_HD0);
783 		if (len > 1)
784 			b[1] = bus_space_read_1(sc->sc_smb_iot, sc->sc_smb_ioh,
785 			    PIIX_SMB_HD1);
786 	}
787 
788 done:
789 	sc->sc_i2c_xfer.done = true;
790 	if ((sc->sc_i2c_xfer.flags & I2C_F_POLL) == 0) {
791 		cv_signal(&sc->sc_exec_wait);
792 		mutex_exit(&sc->sc_exec_lock);
793 	}
794 	return (1);
795 }
796