xref: /freebsd/sys/dev/tpm/tpm.c (revision 3c5ba95ad12285ad37c182a4bfc1b240ec6d18a7)
1 /*
2  * Copyright (c) 2008, 2009 Michael Shalayeff
3  * Copyright (c) 2009, 2010 Hans-Joerg Hoexer
4  * All rights reserved.
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 MIND, USE, DATA OR PROFITS, WHETHER IN
15  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
16  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 /* #define	TPM_DEBUG */
20 
21 #include <sys/cdefs.h>
22 __FBSDID("$FreeBSD$");
23 
24 #include <sys/param.h>
25 #include <sys/systm.h>
26 #include <sys/kernel.h>
27 #include <sys/malloc.h>
28 #include <sys/proc.h>
29 
30 #ifdef __FreeBSD__
31 #include <sys/module.h>
32 #include <sys/conf.h>
33 #include <sys/uio.h>
34 #include <sys/bus.h>
35 
36 #include <machine/bus.h>
37 #include <sys/rman.h>
38 #include <machine/resource.h>
39 
40 #include <machine/md_var.h>
41 
42 #include <isa/isareg.h>
43 #include <isa/isavar.h>
44 #else
45 #include <sys/device.h>
46 
47 #include <machine/cpu.h>
48 #include <machine/bus.h>
49 #include <machine/intr.h>
50 #include <machine/conf.h>
51 
52 #include <dev/isa/isareg.h>
53 #include <dev/isa/isavar.h>
54 #endif
55 #include <dev/tpm/tpmvar.h>
56 
57 #ifndef __FreeBSD__
58 /* XXX horrible hack for tcsd (-lpthread) workaround on OpenBSD */
59 #undef PCATCH
60 #define PCATCH	0
61 #endif
62 
63 #define	TPM_BUFSIZ	1024
64 
65 #define TPM_HDRSIZE	10
66 
67 #define TPM_PARAM_SIZE	0x0001
68 
69 #ifdef __FreeBSD__
70 #define IRQUNK	-1
71 #endif
72 
73 #define	TPM_ACCESS			0x0000	/* access register */
74 #define	TPM_ACCESS_ESTABLISHMENT	0x01	/* establishment */
75 #define	TPM_ACCESS_REQUEST_USE		0x02	/* request using locality */
76 #define	TPM_ACCESS_REQUEST_PENDING	0x04	/* pending request */
77 #define	TPM_ACCESS_SEIZE		0x08	/* request locality seize */
78 #define	TPM_ACCESS_SEIZED		0x10	/* locality has been seized */
79 #define	TPM_ACCESS_ACTIVE_LOCALITY	0x20	/* locality is active */
80 #define	TPM_ACCESS_VALID		0x80	/* bits are valid */
81 #define	TPM_ACCESS_BITS	\
82     "\020\01EST\02REQ\03PEND\04SEIZE\05SEIZED\06ACT\010VALID"
83 
84 #define	TPM_INTERRUPT_ENABLE	0x0008
85 #define	TPM_GLOBAL_INT_ENABLE	0x80000000	/* enable ints */
86 #define	TPM_CMD_READY_INT	0x00000080	/* cmd ready enable */
87 #define	TPM_INT_EDGE_FALLING	0x00000018
88 #define	TPM_INT_EDGE_RISING	0x00000010
89 #define	TPM_INT_LEVEL_LOW	0x00000008
90 #define	TPM_INT_LEVEL_HIGH	0x00000000
91 #define	TPM_LOCALITY_CHANGE_INT	0x00000004	/* locality change enable */
92 #define	TPM_STS_VALID_INT	0x00000002	/* int on TPM_STS_VALID is set */
93 #define	TPM_DATA_AVAIL_INT	0x00000001	/* int on TPM_STS_DATA_AVAIL is set */
94 #define	TPM_INTERRUPT_ENABLE_BITS \
95     "\020\040ENA\010RDY\03LOCH\02STSV\01DRDY"
96 
97 #define	TPM_INT_VECTOR		0x000c	/* 8 bit reg for 4 bit irq vector */
98 #define	TPM_INT_STATUS		0x0010	/* bits are & 0x87 from TPM_INTERRUPT_ENABLE */
99 
100 #define	TPM_INTF_CAPABILITIES		0x0014	/* capability register */
101 #define	TPM_INTF_BURST_COUNT_STATIC	0x0100	/* TPM_STS_BMASK static */
102 #define	TPM_INTF_CMD_READY_INT		0x0080	/* int on ready supported */
103 #define	TPM_INTF_INT_EDGE_FALLING	0x0040	/* falling edge ints supported */
104 #define	TPM_INTF_INT_EDGE_RISING	0x0020	/* rising edge ints supported */
105 #define	TPM_INTF_INT_LEVEL_LOW		0x0010	/* level-low ints supported */
106 #define	TPM_INTF_INT_LEVEL_HIGH		0x0008	/* level-high ints supported */
107 #define	TPM_INTF_LOCALITY_CHANGE_INT	0x0004	/* locality-change int (mb 1) */
108 #define	TPM_INTF_STS_VALID_INT		0x0002	/* TPM_STS_VALID int supported */
109 #define	TPM_INTF_DATA_AVAIL_INT		0x0001	/* TPM_STS_DATA_AVAIL int supported (mb 1) */
110 #define	TPM_CAPSREQ \
111   (TPM_INTF_DATA_AVAIL_INT|TPM_INTF_LOCALITY_CHANGE_INT|TPM_INTF_INT_LEVEL_LOW)
112 #define	TPM_CAPBITS \
113   "\020\01IDRDY\02ISTSV\03ILOCH\04IHIGH\05ILOW\06IEDGE\07IFALL\010IRDY\011BCST"
114 
115 #define	TPM_STS			0x0018		/* status register */
116 #define TPM_STS_MASK		0x000000ff	/* status bits */
117 #define	TPM_STS_BMASK		0x00ffff00	/* ro io burst size */
118 #define	TPM_STS_VALID		0x00000080	/* ro other bits are valid */
119 #define	TPM_STS_CMD_READY	0x00000040	/* rw chip/signal ready */
120 #define	TPM_STS_GO		0x00000020	/* wo start the command */
121 #define	TPM_STS_DATA_AVAIL	0x00000010	/* ro data available */
122 #define	TPM_STS_DATA_EXPECT	0x00000008	/* ro more data to be written */
123 #define	TPM_STS_RESP_RETRY	0x00000002	/* wo resend the response */
124 #define	TPM_STS_BITS	"\020\010VALID\07RDY\06GO\05DRDY\04EXPECT\02RETRY"
125 
126 #define	TPM_DATA	0x0024
127 #define	TPM_ID		0x0f00
128 #define	TPM_REV		0x0f04
129 #define	TPM_SIZE	0x5000		/* five pages of the above */
130 
131 #define	TPM_ACCESS_TMO	2000		/* 2sec */
132 #define	TPM_READY_TMO	2000		/* 2sec */
133 #define	TPM_READ_TMO	120000		/* 2 minutes */
134 #define TPM_BURST_TMO	2000		/* 2sec */
135 
136 #define	TPM_LEGACY_BUSY	0x01
137 #define	TPM_LEGACY_ABRT	0x01
138 #define	TPM_LEGACY_DA	0x02
139 #define	TPM_LEGACY_RE	0x04
140 #define	TPM_LEGACY_LAST	0x04
141 #define	TPM_LEGACY_BITS	"\020\01BUSY\2DA\3RE\4LAST"
142 #define	TPM_LEGACY_TMO		(2*60)	/* sec */
143 #define	TPM_LEGACY_SLEEP	5	/* ticks */
144 #define	TPM_LEGACY_DELAY	100
145 
146 /* Set when enabling legacy interface in host bridge. */
147 int tpm_enabled;
148 
149 
150 #ifdef __FreeBSD__
151 #define	TPMSOFTC(dev) \
152 	((struct tpm_softc *)dev->si_drv1)
153 
154 d_open_t	tpmopen;
155 d_close_t	tpmclose;
156 d_read_t	tpmread;
157 d_write_t	tpmwrite;
158 d_ioctl_t	tpmioctl;
159 
160 static struct cdevsw tpm_cdevsw = {
161 	.d_version =	D_VERSION,
162 	.d_flags =	D_NEEDGIANT,
163 	.d_open =	tpmopen,
164 	.d_close =	tpmclose,
165 	.d_read =	tpmread,
166 	.d_write =	tpmwrite,
167 	.d_ioctl =	tpmioctl,
168 	.d_name =	"tpm",
169 };
170 #else
171 #define	TPMSOFTC(dev) \
172     (struct tpm_softc *)device_lookup(&tpm_cd, minor(dev))
173 
174 struct cfdriver tpm_cd = {
175 	NULL, "tpm", DV_DULL
176 };
177 
178 int	tpm_match(device_t , void *, void *);
179 void	tpm_attach(device_t , device_t , void *);
180 
181 struct cfattach tpm_ca = {
182 	sizeof(struct tpm_softc), tpm_match, tpm_attach
183 };
184 #endif
185 
186 const struct {
187 	u_int32_t devid;
188 	char name[32];
189 	int flags;
190 #define TPM_DEV_NOINTS	0x0001
191 } tpm_devs[] = {
192 	{ 0x000615d1, "IFX SLD 9630 TT 1.1", 0 },
193 	{ 0x000b15d1, "IFX SLB 9635 TT 1.2", 0 },
194 	{ 0x100214e4, "Broadcom BCM0102", TPM_DEV_NOINTS },
195 	{ 0x00fe1050, "WEC WPCT200", 0 },
196 	{ 0x687119fa, "SNS SSX35", 0 },
197 	{ 0x2e4d5453, "STM ST19WP18", 0 },
198 	{ 0x32021114, "ATML 97SC3203", TPM_DEV_NOINTS },
199 	{ 0x10408086, "INTEL INTC0102", 0 },
200 	{ 0, "", TPM_DEV_NOINTS },
201 };
202 
203 int tpm_tis12_irqinit(struct tpm_softc *, int, int);
204 int tpm_tis12_init(struct tpm_softc *, int, const char *);
205 int tpm_tis12_start(struct tpm_softc *, int);
206 int tpm_tis12_read(struct tpm_softc *, void *, int, size_t *, int);
207 int tpm_tis12_write(struct tpm_softc *, void *, int);
208 int tpm_tis12_end(struct tpm_softc *, int, int);
209 
210 #ifdef __FreeBSD__
211 void tpm_intr(void *);
212 #else
213 int tpm_intr(void *);
214 void tpm_powerhook(int, void *);
215 int tpm_suspend(struct tpm_softc *, int);
216 int tpm_resume(struct tpm_softc *, int);
217 #endif
218 
219 int tpm_waitfor_poll(struct tpm_softc *, u_int8_t, int, void *);
220 int tpm_waitfor_int(struct tpm_softc *, u_int8_t, int, void *, int);
221 int tpm_waitfor(struct tpm_softc *, u_int8_t, int, void *);
222 int tpm_request_locality(struct tpm_softc *, int);
223 int tpm_getburst(struct tpm_softc *);
224 u_int8_t tpm_status(struct tpm_softc *);
225 int tpm_tmotohz(int);
226 
227 int tpm_legacy_probe(bus_space_tag_t, bus_addr_t);
228 int tpm_legacy_init(struct tpm_softc *, int, const char *);
229 int tpm_legacy_start(struct tpm_softc *, int);
230 int tpm_legacy_read(struct tpm_softc *, void *, int, size_t *, int);
231 int tpm_legacy_write(struct tpm_softc *, void *, int);
232 int tpm_legacy_end(struct tpm_softc *, int, int);
233 
234 #ifdef __FreeBSD__
235 
236 /*
237  * FreeBSD specific code for probing and attaching TPM to device tree.
238  */
239 #if 0
240 static void
241 tpm_identify(driver_t *driver, device_t parent)
242 {
243 	BUS_ADD_CHILD(parent, ISA_ORDER_SPECULATIVE, "tpm", 0);
244 }
245 #endif
246 
247 
248 int
249 tpm_attach(device_t dev)
250 {
251 	struct tpm_softc *sc = device_get_softc(dev);
252 	int irq;
253 
254 	sc->mem_rid = 0;
255 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &sc->mem_rid,
256 	    RF_ACTIVE);
257 	if (sc->mem_res == NULL)
258 		return ENXIO;
259 
260 	sc->sc_bt = rman_get_bustag(sc->mem_res);
261 	sc->sc_bh = rman_get_bushandle(sc->mem_res);
262 
263 	sc->irq_rid = 0;
264 	sc->irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &sc->irq_rid,
265 	    RF_ACTIVE | RF_SHAREABLE);
266 	if (sc->irq_res != NULL)
267 		irq = rman_get_start(sc->irq_res);
268 	else
269 		irq = IRQUNK;
270 
271 	/* In case PnP probe this may contain some initialization. */
272 	tpm_tis12_probe(sc->sc_bt, sc->sc_bh);
273 
274 	if (tpm_legacy_probe(sc->sc_bt, sc->sc_bh)) {
275 		sc->sc_init = tpm_legacy_init;
276 		sc->sc_start = tpm_legacy_start;
277 		sc->sc_read = tpm_legacy_read;
278 		sc->sc_write = tpm_legacy_write;
279 		sc->sc_end = tpm_legacy_end;
280 	} else {
281 		sc->sc_init = tpm_tis12_init;
282 		sc->sc_start = tpm_tis12_start;
283 		sc->sc_read = tpm_tis12_read;
284 		sc->sc_write = tpm_tis12_write;
285 		sc->sc_end = tpm_tis12_end;
286 	}
287 
288 	printf("%s", device_get_name(dev));
289 	if ((sc->sc_init)(sc, irq, "tpm")) {
290 		tpm_detach(dev);
291 		return ENXIO;
292 	}
293 
294 	if (sc->sc_init == tpm_tis12_init && sc->irq_res != NULL &&
295 	    bus_setup_intr(dev, sc->irq_res, INTR_TYPE_TTY, NULL,
296 	    tpm_intr, sc, &sc->intr_cookie) != 0) {
297 		tpm_detach(dev);
298 		printf(": cannot establish interrupt\n");
299 		return 1;
300 	}
301 
302 	sc->sc_cdev = make_dev(&tpm_cdevsw, device_get_unit(dev),
303 			    UID_ROOT, GID_WHEEL, 0600, "tpm");
304 	sc->sc_cdev->si_drv1 = sc;
305 
306 	return 0;
307 }
308 
309 int
310 tpm_detach(device_t dev)
311 {
312 	struct tpm_softc * sc = device_get_softc(dev);
313 
314 	if(sc->intr_cookie){
315 		bus_teardown_intr(dev, sc->irq_res, sc->intr_cookie);
316 	}
317 
318 	if(sc->mem_res){
319 		bus_release_resource(dev, SYS_RES_MEMORY,
320 				     sc->mem_rid, sc->mem_res);
321 	}
322 
323 	if(sc->irq_res){
324 		bus_release_resource(dev, SYS_RES_IRQ,
325 				     sc->irq_rid, sc->irq_res);
326 	}
327 	if(sc->sc_cdev){
328 		destroy_dev(sc->sc_cdev);
329 	}
330 
331 	return 0;
332 }
333 
334 
335 #else
336 /*
337  * OpenBSD specific code for probing and attaching TPM to device tree.
338  */
339 int
340 tpm_match(device_t parent, void *match, void *aux)
341 {
342 	struct isa_attach_args *ia = aux;
343 	struct cfdata *cf = match;
344 	bus_space_tag_t bt = ia->ia_memt;
345 	bus_space_handle_t bh;
346 	int rv;
347 
348 	/* There can be only one. */
349 	if (cf->cf_unit)
350 		return 0;
351 
352 	if (tpm_legacy_probe(ia->ia_iot, ia->ia_iobase)) {
353 		ia->ia_iosize = 2;
354 		return 1;
355 	}
356 
357 	if (ia->ia_maddr == -1)
358 		return 0;
359 
360 	if (bus_space_map(bt, ia->ia_maddr, TPM_SIZE, 0, &bh))
361 		return 0;
362 
363 	if ((rv = tpm_tis12_probe(bt, bh))) {
364 		ia->ia_iosize = 0;
365 		ia->ia_msize = TPM_SIZE;
366 	}
367 
368 	bus_space_unmap(bt, bh, TPM_SIZE);
369 	return rv;
370 }
371 
372 void
373 tpm_attach(device_t parent, device_t self, void *aux)
374 {
375 	struct tpm_softc *sc = (struct tpm_softc *)self;
376 	struct isa_attach_args *ia = aux;
377 	bus_addr_t iobase;
378 	bus_size_t size;
379 	int rv;
380 
381 	if (tpm_legacy_probe(ia->ia_iot, ia->ia_iobase)) {
382 		sc->sc_bt = ia->ia_iot;
383 		iobase = ia->ia_iobase;
384 		size = ia->ia_iosize;
385 		sc->sc_batm = ia->ia_iot;
386 		sc->sc_init = tpm_legacy_init;
387 		sc->sc_start = tpm_legacy_start;
388 		sc->sc_read = tpm_legacy_read;
389 		sc->sc_write = tpm_legacy_write;
390 		sc->sc_end = tpm_legacy_end;
391 	} else {
392 		sc->sc_bt = ia->ia_memt;
393 		iobase = ia->ia_maddr;
394 		size = TPM_SIZE;
395 		sc->sc_init = tpm_tis12_init;
396 		sc->sc_start = tpm_tis12_start;
397 		sc->sc_read = tpm_tis12_read;
398 		sc->sc_write = tpm_tis12_write;
399 		sc->sc_end = tpm_tis12_end;
400 	}
401 
402 	if (bus_space_map(sc->sc_bt, iobase, size, 0, &sc->sc_bh)) {
403 		printf(": cannot map registers\n");
404 		return;
405 	}
406 
407 	if ((rv = (sc->sc_init)(sc, ia->ia_irq, sc->sc_dev.dv_xname))) {
408 		bus_space_unmap(sc->sc_bt, sc->sc_bh, size);
409 		return;
410 	}
411 
412 	/*
413 	 * Only setup interrupt handler when we have a vector and the
414 	 * chip is TIS 1.2 compliant.
415 	 */
416 	if (sc->sc_init == tpm_tis12_init && ia->ia_irq != IRQUNK &&
417 	    (sc->sc_ih = isa_intr_establish(ia->ia_ic, ia->ia_irq, IST_EDGE,
418 	    IPL_TTY, tpm_intr, sc, sc->sc_dev.dv_xname)) == NULL) {
419 		bus_space_unmap(sc->sc_bt, sc->sc_bh, TPM_SIZE);
420 		printf("%s: cannot establish interrupt\n",
421 		    sc->sc_dev.dv_xname);
422 		return;
423 	}
424 
425 	sc->sc_suspend = PWR_RESUME;
426 	sc->sc_powerhook = powerhook_establish(tpm_powerhook, sc);
427 }
428 #endif
429 
430 /* Probe TPM using TIS 1.2 interface. */
431 int
432 tpm_tis12_probe(bus_space_tag_t bt, bus_space_handle_t bh)
433 {
434 	u_int32_t r;
435 	u_int8_t save, reg;
436 
437 	r = bus_space_read_4(bt, bh, TPM_INTF_CAPABILITIES);
438 	if (r == 0xffffffff)
439 		return 0;
440 
441 #ifdef TPM_DEBUG
442 	printf("tpm: caps=%b\n", r, TPM_CAPBITS);
443 #endif
444 	if ((r & TPM_CAPSREQ) != TPM_CAPSREQ ||
445 	    !(r & (TPM_INTF_INT_EDGE_RISING | TPM_INTF_INT_LEVEL_LOW))) {
446 #ifdef TPM_DEBUG
447 		printf("tpm: caps too low (caps=%b)\n", r, TPM_CAPBITS);
448 #endif
449 		return 0;
450 	}
451 
452 	save = bus_space_read_1(bt, bh, TPM_ACCESS);
453 	bus_space_write_1(bt, bh, TPM_ACCESS, TPM_ACCESS_REQUEST_USE);
454 	reg = bus_space_read_1(bt, bh, TPM_ACCESS);
455 	if ((reg & TPM_ACCESS_VALID) && (reg & TPM_ACCESS_ACTIVE_LOCALITY) &&
456 	    bus_space_read_4(bt, bh, TPM_ID) != 0xffffffff)
457 		return 1;
458 
459 	bus_space_write_1(bt, bh, TPM_ACCESS, save);
460 	return 0;
461 }
462 
463 /*
464  * Setup interrupt vector if one is provided and interrupts are know to
465  * work on that particular chip.
466  */
467 int
468 tpm_tis12_irqinit(struct tpm_softc *sc, int irq, int idx)
469 {
470 	u_int32_t r;
471 
472 	if ((irq == IRQUNK) || (tpm_devs[idx].flags & TPM_DEV_NOINTS)) {
473 		sc->sc_vector = IRQUNK;
474 		return 0;
475 	}
476 
477 	/* Ack and disable all interrupts. */
478 	bus_space_write_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE,
479 	    bus_space_read_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE) &
480 	    ~TPM_GLOBAL_INT_ENABLE);
481 	bus_space_write_4(sc->sc_bt, sc->sc_bh, TPM_INT_STATUS,
482 	    bus_space_read_4(sc->sc_bt, sc->sc_bh, TPM_INT_STATUS));
483 
484 	/* Program interrupt vector. */
485 	bus_space_write_1(sc->sc_bt, sc->sc_bh, TPM_INT_VECTOR, irq);
486 	sc->sc_vector = irq;
487 
488 	/* Program interrupt type. */
489 	if (sc->sc_capabilities & TPM_INTF_INT_EDGE_RISING)
490 		r = TPM_INT_EDGE_RISING;
491 	else if (sc->sc_capabilities & TPM_INTF_INT_LEVEL_HIGH)
492 		r = TPM_INT_LEVEL_HIGH;
493 	else
494 		r = TPM_INT_LEVEL_LOW;
495 	bus_space_write_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE, r);
496 
497 	return 0;
498 }
499 
500 /* Setup TPM using TIS 1.2 interface. */
501 int
502 tpm_tis12_init(struct tpm_softc *sc, int irq, const char *name)
503 {
504 	u_int32_t r;
505 	int i;
506 
507 	r = bus_space_read_4(sc->sc_bt, sc->sc_bh, TPM_INTF_CAPABILITIES);
508 #ifdef TPM_DEBUG
509 	printf(" caps=%b ", r, TPM_CAPBITS);
510 #endif
511 	if ((r & TPM_CAPSREQ) != TPM_CAPSREQ ||
512 	    !(r & (TPM_INTF_INT_EDGE_RISING | TPM_INTF_INT_LEVEL_LOW))) {
513 		printf(": capabilities too low (caps=%b)\n", r, TPM_CAPBITS);
514 		return 1;
515 	}
516 	sc->sc_capabilities = r;
517 
518 	sc->sc_devid = bus_space_read_4(sc->sc_bt, sc->sc_bh, TPM_ID);
519 	sc->sc_rev = bus_space_read_1(sc->sc_bt, sc->sc_bh, TPM_REV);
520 
521 	for (i = 0; tpm_devs[i].devid; i++)
522 		if (tpm_devs[i].devid == sc->sc_devid)
523 			break;
524 
525 	if (tpm_devs[i].devid)
526 		printf(": %s rev 0x%x\n", tpm_devs[i].name, sc->sc_rev);
527 	else
528 		printf(": device 0x%08x rev 0x%x\n", sc->sc_devid, sc->sc_rev);
529 
530 	if (tpm_tis12_irqinit(sc, irq, i))
531 		return 1;
532 
533 	if (tpm_request_locality(sc, 0))
534 		return 1;
535 
536 	/* Abort whatever it thought it was doing. */
537 	bus_space_write_1(sc->sc_bt, sc->sc_bh, TPM_STS, TPM_STS_CMD_READY);
538 
539 	return 0;
540 }
541 
542 int
543 tpm_request_locality(struct tpm_softc *sc, int l)
544 {
545 	u_int32_t r;
546 	int to, rv;
547 
548 	if (l != 0)
549 		return EINVAL;
550 
551 	if ((bus_space_read_1(sc->sc_bt, sc->sc_bh, TPM_ACCESS) &
552 	    (TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY)) ==
553 	    (TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY))
554 		return 0;
555 
556 	bus_space_write_1(sc->sc_bt, sc->sc_bh, TPM_ACCESS,
557 	    TPM_ACCESS_REQUEST_USE);
558 
559 	to = tpm_tmotohz(TPM_ACCESS_TMO);
560 
561 	while ((r = bus_space_read_1(sc->sc_bt, sc->sc_bh, TPM_ACCESS) &
562 	    (TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY)) !=
563 	    (TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY) && to--) {
564 		rv = tsleep(sc->sc_init, PRIBIO | PCATCH, "tpm_locality", 1);
565 		if (rv &&  rv != EWOULDBLOCK) {
566 #ifdef TPM_DEBUG
567 			printf("tpm_request_locality: interrupted %d\n", rv);
568 #endif
569 			return rv;
570 		}
571 	}
572 
573 	if ((r & (TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY)) !=
574 	    (TPM_ACCESS_VALID | TPM_ACCESS_ACTIVE_LOCALITY)) {
575 #ifdef TPM_DEBUG
576 		printf("tpm_request_locality: access %b\n", r, TPM_ACCESS_BITS);
577 #endif
578 		return EBUSY;
579 	}
580 
581 	return 0;
582 }
583 
584 int
585 tpm_getburst(struct tpm_softc *sc)
586 {
587 	int burst, to, rv;
588 
589 	to = tpm_tmotohz(TPM_BURST_TMO);
590 
591 	burst = 0;
592 	while (burst == 0 && to--) {
593 		/*
594 		 * Burst count has to be read from bits 8 to 23 without
595 		 * touching any other bits, eg. the actual status bits 0
596 		 * to 7.
597 		 */
598 		burst = bus_space_read_1(sc->sc_bt, sc->sc_bh, TPM_STS + 1);
599 		burst |= bus_space_read_1(sc->sc_bt, sc->sc_bh, TPM_STS + 2)
600 		    << 8;
601 #ifdef TPM_DEBUG
602 		printf("tpm_getburst: read %d\n", burst);
603 #endif
604 		if (burst)
605 			return burst;
606 
607 		rv = tsleep(sc, PRIBIO | PCATCH, "tpm_getburst", 1);
608 		if (rv && rv != EWOULDBLOCK) {
609 			return 0;
610 		}
611 	}
612 
613 	return 0;
614 }
615 
616 u_int8_t
617 tpm_status(struct tpm_softc *sc)
618 {
619 	u_int8_t status;
620 
621 	status = bus_space_read_1(sc->sc_bt, sc->sc_bh, TPM_STS) &
622 	    TPM_STS_MASK;
623 
624 	return status;
625 }
626 
627 int
628 tpm_tmotohz(int tmo)
629 {
630 	struct timeval tv;
631 
632 	tv.tv_sec = tmo / 1000;
633 	tv.tv_usec = 1000 * (tmo % 1000);
634 
635 	return tvtohz(&tv);
636 }
637 
638 /* Save TPM state on suspend. */
639 int
640 #ifdef __FreeBSD__
641 tpm_suspend(device_t dev)
642 #else
643 tpm_suspend(struct tpm_softc *sc, int why)
644 #endif
645 {
646 #ifdef __FreeBSD__
647 	struct tpm_softc *sc = device_get_softc(dev);
648 	int why = 1;
649 #endif
650 	u_int8_t command[] = {
651 	    0, 193,		/* TPM_TAG_RQU_COMMAND */
652 	    0, 0, 0, 10,	/* Length in bytes */
653 	    0, 0, 0, 156	/* TPM_ORD_SaveStates */
654 	};
655 
656 	/*
657 	 * Power down:  We have to issue the SaveStates command.
658 	 */
659 	sc->sc_write(sc, &command, sizeof(command));
660 	sc->sc_read(sc, &command, sizeof(command), NULL, TPM_HDRSIZE);
661 #ifdef TPM_DEBUG
662 	printf("tpm_suspend: power down: %d -> %d\n", sc->sc_suspend, why);
663 #endif
664 	sc->sc_suspend = why;
665 
666 	return 0;
667 }
668 
669 /*
670  * Handle resume event.  Actually nothing to do as the BIOS is supposed
671  * to restore the previously saved state.
672  */
673 int
674 #ifdef __FreeBSD__
675 tpm_resume(device_t dev)
676 #else
677 tpm_resume(struct tpm_softc *sc, int why)
678 #endif
679 {
680 #ifdef __FreeBSD__
681 	struct tpm_softc *sc = device_get_softc(dev);
682 	int why = 0;
683 #endif
684 #ifdef TPM_DEBUG
685 	printf("tpm_resume: resume: %d -> %d\n", sc->sc_suspend, why);
686 #endif
687 	sc->sc_suspend = why;
688 
689 	return 0;
690 }
691 
692 /* Dispatch suspend and resume events. */
693 #ifndef __FreeBSD__
694 void
695 tpm_powerhook(int why, void *self)
696 {
697 	struct tpm_softc *sc = (struct tpm_softc *)self;
698 
699 	if (why != PWR_RESUME)
700 		tpm_suspend(sc, why);
701 	else
702 		tpm_resume(sc, why);
703 }
704 #endif	/* !__FreeBSD__ */
705 
706 /* Wait for given status bits using polling. */
707 int
708 tpm_waitfor_poll(struct tpm_softc *sc, u_int8_t mask, int tmo, void *c)
709 {
710 	int rv;
711 
712 	/*
713 	 * Poll until either the requested condition or a time out is
714 	 * met.
715 	 */
716 	while (((sc->sc_stat = tpm_status(sc)) & mask) != mask && tmo--) {
717 		rv = tsleep(c, PRIBIO | PCATCH, "tpm_poll", 1);
718 		if (rv && rv != EWOULDBLOCK) {
719 #ifdef TPM_DEBUG
720 			printf("tpm_waitfor_poll: interrupted %d\n", rv);
721 #endif
722 			return rv;
723 		}
724 	}
725 
726 	return 0;
727 }
728 
729 /* Wait for given status bits using interrupts. */
730 int
731 tpm_waitfor_int(struct tpm_softc *sc, u_int8_t mask, int tmo, void *c,
732     int inttype)
733 {
734 	int rv, to;
735 
736 	/* Poll and return when condition is already met. */
737 	sc->sc_stat = tpm_status(sc);
738 	if ((sc->sc_stat & mask) == mask)
739 		return 0;
740 
741 	/*
742 	 * Enable interrupt on tpm chip.  Note that interrupts on our
743 	 * level (SPL_TTY) are disabled (see tpm{read,write} et al) and
744 	 * will not be delivered to the cpu until we call tsleep(9) below.
745 	 */
746 	bus_space_write_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE,
747 	    bus_space_read_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE) |
748 	    inttype);
749 	bus_space_write_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE,
750 	    bus_space_read_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE) |
751 	    TPM_GLOBAL_INT_ENABLE);
752 
753 	/*
754 	 * Poll once more to remedy the race between previous polling
755 	 * and enabling interrupts on the tpm chip.
756 	 */
757 	sc->sc_stat = tpm_status(sc);
758 	if ((sc->sc_stat & mask) == mask) {
759 		rv = 0;
760 		goto out;
761 	}
762 
763 	to = tpm_tmotohz(tmo);
764 #ifdef TPM_DEBUG
765 	printf("tpm_waitfor_int: sleeping for %d ticks on %p\n", to, c);
766 #endif
767 	/*
768 	 * tsleep(9) enables interrupts on the cpu and returns after
769 	 * wake up with interrupts disabled again.  Note that interrupts
770 	 * generated by the tpm chip while being at SPL_TTY are not lost
771 	 * but held and delivered as soon as the cpu goes below SPL_TTY.
772 	 */
773 	rv = tsleep(c, PRIBIO | PCATCH, "tpm_intr", to);
774 
775 	sc->sc_stat = tpm_status(sc);
776 #ifdef TPM_DEBUG
777 	printf("tpm_waitfor_int: woke up with rv %d stat %b\n", rv,
778 	    sc->sc_stat, TPM_STS_BITS);
779 #endif
780 	if ((sc->sc_stat & mask) == mask)
781 		rv = 0;
782 
783 	/* Disable interrupts on tpm chip again. */
784 out:	bus_space_write_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE,
785 	    bus_space_read_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE) &
786 	    ~TPM_GLOBAL_INT_ENABLE);
787 	bus_space_write_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE,
788 	    bus_space_read_4(sc->sc_bt, sc->sc_bh, TPM_INTERRUPT_ENABLE) &
789 	    ~inttype);
790 
791 	return rv;
792 }
793 
794 /*
795  * Wait on given status bits, uses interrupts where possible, otherwise polls.
796  */
797 int
798 tpm_waitfor(struct tpm_softc *sc, u_int8_t b0, int tmo, void *c)
799 {
800 	u_int8_t b;
801 	int re, to, rv;
802 
803 #ifdef TPM_DEBUG
804 	printf("tpm_waitfor: b0 %b\n", b0, TPM_STS_BITS);
805 #endif
806 
807 	/*
808 	 * If possible, use interrupts, otherwise poll.
809 	 *
810 	 * We use interrupts for TPM_STS_VALID and TPM_STS_DATA_AVAIL (if
811 	 * the tpm chips supports them) as waiting for those can take
812 	 * really long.  The other TPM_STS* are not needed very often
813 	 * so we do not support them.
814 	 */
815 	if (sc->sc_vector != IRQUNK) {
816 		b = b0;
817 
818 		/*
819 		 * Wait for data ready.  This interrupt only occurs
820 		 * when both TPM_STS_VALID and TPM_STS_DATA_AVAIL are asserted.
821 		 * Thus we don't have to bother with TPM_STS_VALID
822 		 * separately and can just return.
823 		 *
824 		 * This only holds for interrupts!  When using polling
825 		 * both flags have to be waited for, see below.
826 		 */
827 		if ((b & TPM_STS_DATA_AVAIL) && (sc->sc_capabilities &
828 		    TPM_INTF_DATA_AVAIL_INT))
829 			return tpm_waitfor_int(sc, b, tmo, c,
830 			    TPM_DATA_AVAIL_INT);
831 
832 		/* Wait for status valid bit. */
833 		if ((b & TPM_STS_VALID) && (sc->sc_capabilities &
834 		    TPM_INTF_STS_VALID_INT)) {
835 			rv = tpm_waitfor_int(sc, b, tmo, c, TPM_STS_VALID_INT);
836 			if (rv != 0)
837 				return rv;
838 			else
839 				b = b0 & ~TPM_STS_VALID;
840 		}
841 
842 		/*
843 		 * When all flags are taken care of, return.  Otherwise
844 		 * use polling for eg. TPM_STS_CMD_READY.
845 		 */
846 		if (b == 0)
847 			return 0;
848 	}
849 
850 	re = 3;
851 restart:
852 	/*
853 	 * If requested wait for TPM_STS_VALID before dealing with
854 	 * any other flag.  Eg. when both TPM_STS_DATA_AVAIL and TPM_STS_VALID
855 	 * are requested, wait for the latter first.
856 	 */
857 	b = b0;
858 	if (b0 & TPM_STS_VALID)
859 		b = TPM_STS_VALID;
860 
861 	to = tpm_tmotohz(tmo);
862 again:
863 	if ((rv = tpm_waitfor_poll(sc, b, to, c)) != 0)
864 		return rv;
865 
866 	if ((b & sc->sc_stat) == TPM_STS_VALID) {
867 		/* Now wait for other flags. */
868 		b = b0 & ~TPM_STS_VALID;
869 		to++;
870 		goto again;
871 	}
872 
873 	if ((sc->sc_stat & b) != b) {
874 #ifdef TPM_DEBUG
875 		printf("tpm_waitfor: timeout: stat=%b b=%b\n",
876 		    sc->sc_stat, TPM_STS_BITS, b, TPM_STS_BITS);
877 #endif
878 		if (re-- && (b0 & TPM_STS_VALID)) {
879 			bus_space_write_1(sc->sc_bt, sc->sc_bh, TPM_STS,
880 			    TPM_STS_RESP_RETRY);
881 			goto restart;
882 		}
883 		return EIO;
884 	}
885 
886 	return 0;
887 }
888 
889 /* Start transaction. */
890 int
891 tpm_tis12_start(struct tpm_softc *sc, int flag)
892 {
893 	int rv;
894 
895 	if (flag == UIO_READ) {
896 		rv = tpm_waitfor(sc, TPM_STS_DATA_AVAIL | TPM_STS_VALID,
897 		    TPM_READ_TMO, sc->sc_read);
898 		return rv;
899 	}
900 
901 	/* Own our (0th) locality. */
902 	if ((rv = tpm_request_locality(sc, 0)) != 0)
903 		return rv;
904 
905 	sc->sc_stat = tpm_status(sc);
906 	if (sc->sc_stat & TPM_STS_CMD_READY) {
907 #ifdef TPM_DEBUG
908 		printf("tpm_tis12_start: UIO_WRITE status %b\n", sc->sc_stat,
909 		   TPM_STS_BITS);
910 #endif
911 		return 0;
912 	}
913 
914 #ifdef TPM_DEBUG
915 	printf("tpm_tis12_start: UIO_WRITE readying chip\n");
916 #endif
917 
918 	/* Abort previous and restart. */
919 	bus_space_write_1(sc->sc_bt, sc->sc_bh, TPM_STS, TPM_STS_CMD_READY);
920 	if ((rv = tpm_waitfor(sc, TPM_STS_CMD_READY, TPM_READY_TMO,
921 	    sc->sc_write))) {
922 #ifdef TPM_DEBUG
923 		printf("tpm_tis12_start: UIO_WRITE readying failed %d\n", rv);
924 #endif
925 		return rv;
926 	}
927 
928 #ifdef TPM_DEBUG
929 	printf("tpm_tis12_start: UIO_WRITE readying done\n");
930 #endif
931 
932 	return 0;
933 }
934 
935 int
936 tpm_tis12_read(struct tpm_softc *sc, void *buf, int len, size_t *count,
937     int flags)
938 {
939 	u_int8_t *p = buf;
940 	size_t cnt;
941 	int rv, n, bcnt;
942 
943 #ifdef TPM_DEBUG
944 	printf("tpm_tis12_read: len %d\n", len);
945 #endif
946 	cnt = 0;
947 	while (len > 0) {
948 		if ((rv = tpm_waitfor(sc, TPM_STS_DATA_AVAIL | TPM_STS_VALID,
949 		    TPM_READ_TMO, sc->sc_read)))
950 			return rv;
951 
952 		bcnt = tpm_getburst(sc);
953 		n = MIN(len, bcnt);
954 #ifdef TPM_DEBUG
955 		printf("tpm_tis12_read: fetching %d, burst is %d\n", n, bcnt);
956 #endif
957 		for (; n--; len--) {
958 			*p++ = bus_space_read_1(sc->sc_bt, sc->sc_bh, TPM_DATA);
959 			cnt++;
960 		}
961 
962 		if ((flags & TPM_PARAM_SIZE) == 0 && cnt >= 6)
963 			break;
964 	}
965 #ifdef TPM_DEBUG
966 	printf("tpm_tis12_read: read %zd bytes, len %d\n", cnt, len);
967 #endif
968 
969 	if (count)
970 		*count = cnt;
971 
972 	return 0;
973 }
974 
975 int
976 tpm_tis12_write(struct tpm_softc *sc, void *buf, int len)
977 {
978 	u_int8_t *p = buf;
979 	size_t cnt;
980 	int rv, r;
981 
982 #ifdef TPM_DEBUG
983 	printf("tpm_tis12_write: sc %p buf %p len %d\n", sc, buf, len);
984 #endif
985 
986 	if ((rv = tpm_request_locality(sc, 0)) != 0)
987 		return rv;
988 
989 	cnt = 0;
990 	while (cnt < len - 1) {
991 		for (r = tpm_getburst(sc); r > 0 && cnt < len - 1; r--) {
992 			bus_space_write_1(sc->sc_bt, sc->sc_bh, TPM_DATA, *p++);
993 			cnt++;
994 		}
995 		if ((rv = tpm_waitfor(sc, TPM_STS_VALID, TPM_READ_TMO, sc))) {
996 #ifdef TPM_DEBUG
997 			printf("tpm_tis12_write: failed burst rv %d\n", rv);
998 #endif
999 			return rv;
1000 		}
1001 		sc->sc_stat = tpm_status(sc);
1002 		if (!(sc->sc_stat & TPM_STS_DATA_EXPECT)) {
1003 #ifdef TPM_DEBUG
1004 			printf("tpm_tis12_write: failed rv %d stat=%b\n", rv,
1005 			    sc->sc_stat, TPM_STS_BITS);
1006 #endif
1007 			return EIO;
1008 		}
1009 	}
1010 
1011 	bus_space_write_1(sc->sc_bt, sc->sc_bh, TPM_DATA, *p++);
1012 	cnt++;
1013 
1014 	if ((rv = tpm_waitfor(sc, TPM_STS_VALID, TPM_READ_TMO, sc))) {
1015 #ifdef TPM_DEBUG
1016 		printf("tpm_tis12_write: failed last byte rv %d\n", rv);
1017 #endif
1018 		return rv;
1019 	}
1020 	if ((sc->sc_stat & TPM_STS_DATA_EXPECT) != 0) {
1021 #ifdef TPM_DEBUG
1022 		printf("tpm_tis12_write: failed rv %d stat=%b\n", rv,
1023 		    sc->sc_stat, TPM_STS_BITS);
1024 #endif
1025 		return EIO;
1026 	}
1027 
1028 #ifdef TPM_DEBUG
1029 	printf("tpm_tis12_write: wrote %d byte\n", cnt);
1030 #endif
1031 
1032 	return 0;
1033 }
1034 
1035 /* Finish transaction. */
1036 int
1037 tpm_tis12_end(struct tpm_softc *sc, int flag, int err)
1038 {
1039 	int rv = 0;
1040 
1041 	if (flag == UIO_READ) {
1042 		if ((rv = tpm_waitfor(sc, TPM_STS_VALID, TPM_READ_TMO,
1043 		    sc->sc_read)))
1044 			return rv;
1045 
1046 		/* Still more data? */
1047 		sc->sc_stat = tpm_status(sc);
1048 		if (!err && ((sc->sc_stat & TPM_STS_DATA_AVAIL) == TPM_STS_DATA_AVAIL)) {
1049 #ifdef TPM_DEBUG
1050 			printf("tpm_tis12_end: read failed stat=%b\n",
1051 			    sc->sc_stat, TPM_STS_BITS);
1052 #endif
1053 			rv = EIO;
1054 		}
1055 
1056 		bus_space_write_1(sc->sc_bt, sc->sc_bh, TPM_STS,
1057 		    TPM_STS_CMD_READY);
1058 
1059 		/* Release our (0th) locality. */
1060 		bus_space_write_1(sc->sc_bt, sc->sc_bh,TPM_ACCESS,
1061 		    TPM_ACCESS_ACTIVE_LOCALITY);
1062 	} else {
1063 		/* Hungry for more? */
1064 		sc->sc_stat = tpm_status(sc);
1065 		if (!err && (sc->sc_stat & TPM_STS_DATA_EXPECT)) {
1066 #ifdef TPM_DEBUG
1067 			printf("tpm_tis12_end: write failed stat=%b\n",
1068 			    sc->sc_stat, TPM_STS_BITS);
1069 #endif
1070 			rv = EIO;
1071 		}
1072 
1073 		bus_space_write_1(sc->sc_bt, sc->sc_bh, TPM_STS,
1074 		    err ? TPM_STS_CMD_READY : TPM_STS_GO);
1075 	}
1076 
1077 	return rv;
1078 }
1079 
1080 #ifdef __FreeBSD__
1081 void
1082 #else
1083 int
1084 #endif
1085 tpm_intr(void *v)
1086 {
1087 	struct tpm_softc *sc = v;
1088 	u_int32_t r;
1089 #ifdef TPM_DEBUG
1090 	static int cnt = 0;
1091 #endif
1092 
1093 	r = bus_space_read_4(sc->sc_bt, sc->sc_bh, TPM_INT_STATUS);
1094 #ifdef TPM_DEBUG
1095 	if (r != 0)
1096 		printf("tpm_intr: int=%b (%d)\n", r, TPM_INTERRUPT_ENABLE_BITS,
1097 		    cnt);
1098 	else
1099 		cnt++;
1100 #endif
1101 	if (!(r & (TPM_CMD_READY_INT | TPM_LOCALITY_CHANGE_INT |
1102 	    TPM_STS_VALID_INT | TPM_DATA_AVAIL_INT)))
1103 #ifdef __FreeBSD__
1104 		return;
1105 #else
1106 		return 0;
1107 #endif
1108 	if (r & TPM_STS_VALID_INT)
1109 		wakeup(sc);
1110 
1111 	if (r & TPM_CMD_READY_INT)
1112 		wakeup(sc->sc_write);
1113 
1114 	if (r & TPM_DATA_AVAIL_INT)
1115 		wakeup(sc->sc_read);
1116 
1117 	if (r & TPM_LOCALITY_CHANGE_INT)
1118 		wakeup(sc->sc_init);
1119 
1120 	bus_space_write_4(sc->sc_bt, sc->sc_bh, TPM_INT_STATUS, r);
1121 
1122 #ifdef __FreeBSD__
1123 	return;
1124 #else
1125 	return 1;
1126 #endif
1127 }
1128 
1129 /* Read single byte using legacy interface. */
1130 static inline u_int8_t
1131 tpm_legacy_in(bus_space_tag_t iot, bus_space_handle_t ioh, int reg)
1132 {
1133 	bus_space_write_1(iot, ioh, 0, reg);
1134 	return bus_space_read_1(iot, ioh, 1);
1135 }
1136 
1137 #if 0
1138 /* Write single byte using legacy interface. */
1139 static inline void
1140 tpm_legacy_out(bus_space_tag_t iot, bus_space_handle_t ioh, int reg, u_int8_t v)
1141 {
1142 	bus_space_write_1(iot, ioh, 0, reg);
1143 	bus_space_write_1(iot, ioh, 1, v);
1144 }
1145 #endif
1146 
1147 /* Probe for TPM using legacy interface. */
1148 int
1149 tpm_legacy_probe(bus_space_tag_t iot, bus_addr_t iobase)
1150 {
1151 	bus_space_handle_t ioh;
1152 	u_int8_t r, v;
1153 	int i, rv = 0;
1154 	char id[8];
1155 
1156 	if (!tpm_enabled || iobase == -1)
1157 		return 0;
1158 
1159 	if (bus_space_map(iot, iobase, 2, 0, &ioh))
1160 		return 0;
1161 
1162 	v = bus_space_read_1(iot, ioh, 0);
1163 	if (v == 0xff) {
1164 		bus_space_unmap(iot, ioh, 2);
1165 		return 0;
1166 	}
1167 	r = bus_space_read_1(iot, ioh, 1);
1168 
1169 	for (i = sizeof(id); i--; )
1170 		id[i] = tpm_legacy_in(iot, ioh, TPM_ID + i);
1171 
1172 #ifdef TPM_DEBUG
1173 	printf("tpm_legacy_probe %.4s %d.%d.%d.%d\n",
1174 	    &id[4], id[0], id[1], id[2], id[3]);
1175 #endif
1176 	/*
1177 	 * The only chips using the legacy interface we are aware of are
1178 	 * by Atmel.  For other chips more signature would have to be added.
1179 	 */
1180 	if (!bcmp(&id[4], "ATML", 4))
1181 		rv = 1;
1182 
1183 	if (!rv) {
1184 		bus_space_write_1(iot, ioh, r, 1);
1185 		bus_space_write_1(iot, ioh, v, 0);
1186 	}
1187 	bus_space_unmap(iot, ioh, 2);
1188 
1189 	return rv;
1190 }
1191 
1192 /* Setup TPM using legacy interface. */
1193 int
1194 tpm_legacy_init(struct tpm_softc *sc, int irq, const char *name)
1195 {
1196 	char id[8];
1197 	u_int8_t ioh, iol;
1198 	int i;
1199 
1200 	if ((i = bus_space_map(sc->sc_batm, tpm_enabled, 2, 0, &sc->sc_bahm))) {
1201 		printf(": cannot map tpm registers (%d)\n", i);
1202 		tpm_enabled = 0;
1203 		return 1;
1204 	}
1205 
1206 	for (i = sizeof(id); i--; )
1207 		id[i] = tpm_legacy_in(sc->sc_bt, sc->sc_bh, TPM_ID + i);
1208 
1209 	printf(": %.4s %d.%d @0x%x\n", &id[4], id[0], id[1], tpm_enabled);
1210 	iol = tpm_enabled & 0xff;
1211 	ioh = tpm_enabled >> 16;
1212 	tpm_enabled = 0;
1213 
1214 	return 0;
1215 }
1216 
1217 /* Start transaction. */
1218 int
1219 tpm_legacy_start(struct tpm_softc *sc, int flag)
1220 {
1221 	struct timeval tv;
1222 	u_int8_t bits, r;
1223 	int to, rv;
1224 
1225 	bits = flag == UIO_READ ? TPM_LEGACY_DA : 0;
1226 	tv.tv_sec = TPM_LEGACY_TMO;
1227 	tv.tv_usec = 0;
1228 	to = tvtohz(&tv) / TPM_LEGACY_SLEEP;
1229 	while (((r = bus_space_read_1(sc->sc_batm, sc->sc_bahm, 1)) &
1230 	    (TPM_LEGACY_BUSY|bits)) != bits && to--) {
1231 		rv = tsleep(sc, PRIBIO | PCATCH, "legacy_tpm_start",
1232 		    TPM_LEGACY_SLEEP);
1233 		if (rv && rv != EWOULDBLOCK)
1234 			return rv;
1235 	}
1236 
1237 #if defined(TPM_DEBUG) && !defined(__FreeBSD__)
1238 	printf("%s: bits %b\n", sc->sc_dev.dv_xname, r, TPM_LEGACY_BITS);
1239 #endif
1240 	if ((r & (TPM_LEGACY_BUSY|bits)) != bits)
1241 		return EIO;
1242 
1243 	return 0;
1244 }
1245 
1246 int
1247 tpm_legacy_read(struct tpm_softc *sc, void *buf, int len, size_t *count,
1248     int flags)
1249 {
1250 	u_int8_t *p;
1251 	size_t cnt;
1252 	int to, rv;
1253 
1254 	cnt = rv = 0;
1255 	for (p = buf; !rv && len > 0; len--) {
1256 		for (to = 1000;
1257 		    !(bus_space_read_1(sc->sc_batm, sc->sc_bahm, 1) &
1258 		    TPM_LEGACY_DA); DELAY(1))
1259 			if (!to--)
1260 				return EIO;
1261 
1262 		DELAY(TPM_LEGACY_DELAY);
1263 		*p++ = bus_space_read_1(sc->sc_batm, sc->sc_bahm, 0);
1264 		cnt++;
1265 	}
1266 
1267 	*count = cnt;
1268 	return 0;
1269 }
1270 
1271 int
1272 tpm_legacy_write(struct tpm_softc *sc, void *buf, int len)
1273 {
1274 	u_int8_t *p;
1275 	int n;
1276 
1277 	for (p = buf, n = len; n--; DELAY(TPM_LEGACY_DELAY)) {
1278 		if (!n && len != TPM_BUFSIZ) {
1279 			bus_space_write_1(sc->sc_batm, sc->sc_bahm, 1,
1280 			    TPM_LEGACY_LAST);
1281 			DELAY(TPM_LEGACY_DELAY);
1282 		}
1283 		bus_space_write_1(sc->sc_batm, sc->sc_bahm, 0, *p++);
1284 	}
1285 
1286 	return 0;
1287 }
1288 
1289 /* Finish transaction. */
1290 int
1291 tpm_legacy_end(struct tpm_softc *sc, int flag, int rv)
1292 {
1293 	struct timeval tv;
1294 	u_int8_t r;
1295 	int to;
1296 
1297 	if (rv || flag == UIO_READ)
1298 		bus_space_write_1(sc->sc_batm, sc->sc_bahm, 1, TPM_LEGACY_ABRT);
1299 	else {
1300 		tv.tv_sec = TPM_LEGACY_TMO;
1301 		tv.tv_usec = 0;
1302 		to = tvtohz(&tv) / TPM_LEGACY_SLEEP;
1303 		while(((r = bus_space_read_1(sc->sc_batm, sc->sc_bahm, 1)) &
1304 		    TPM_LEGACY_BUSY) && to--) {
1305 			rv = tsleep(sc, PRIBIO | PCATCH, "legacy_tpm_end",
1306 			    TPM_LEGACY_SLEEP);
1307 			if (rv && rv != EWOULDBLOCK)
1308 				return rv;
1309 		}
1310 
1311 #if defined(TPM_DEBUG) && !defined(__FreeBSD__)
1312 		printf("%s: bits %b\n", sc->sc_dev.dv_xname, r, TPM_LEGACY_BITS);
1313 #endif
1314 		if (r & TPM_LEGACY_BUSY)
1315 			return EIO;
1316 
1317 		if (r & TPM_LEGACY_RE)
1318 			return EIO;	/* XXX Retry the loop? */
1319 	}
1320 
1321 	return rv;
1322 }
1323 
1324 int
1325 #ifdef __FreeBSD__
1326 tpmopen(struct cdev *dev, int flag, int mode, struct thread *td)
1327 #else
1328 tpmopen(dev_t dev, int flag, int mode, struct proc *p)
1329 #endif
1330 {
1331 	struct tpm_softc *sc = TPMSOFTC(dev);
1332 
1333 	if (!sc)
1334 		return ENXIO;
1335 
1336 	if (sc->sc_flags & TPM_OPEN)
1337 		return EBUSY;
1338 
1339 	sc->sc_flags |= TPM_OPEN;
1340 
1341 	return 0;
1342 }
1343 
1344 int
1345 #ifdef __FreeBSD__
1346 tpmclose(struct cdev *dev, int flag, int mode, struct thread *td)
1347 #else
1348 tpmclose(dev_t dev, int flag, int mode, struct proc *p)
1349 #endif
1350 {
1351 	struct tpm_softc *sc = TPMSOFTC(dev);
1352 
1353 	if (!sc)
1354 		return ENXIO;
1355 
1356 	if (!(sc->sc_flags & TPM_OPEN))
1357 		return EINVAL;
1358 
1359 	sc->sc_flags &= ~TPM_OPEN;
1360 
1361 	return 0;
1362 }
1363 
1364 int
1365 #ifdef __FreeBSD__
1366 tpmread(struct cdev *dev, struct uio *uio, int flags)
1367 #else
1368 tpmread(dev_t dev, struct uio *uio, int flags)
1369 #endif
1370 {
1371 	struct tpm_softc *sc = TPMSOFTC(dev);
1372 	u_int8_t buf[TPM_BUFSIZ], *p;
1373 	size_t cnt;
1374 	int n, len, rv, s;
1375 
1376 	if (!sc)
1377 		return ENXIO;
1378 
1379 	s = spltty();
1380 	if ((rv = (sc->sc_start)(sc, UIO_READ))) {
1381 		splx(s);
1382 		return rv;
1383 	}
1384 
1385 #ifdef TPM_DEBUG
1386 	printf("tpmread: getting header\n");
1387 #endif
1388 	if ((rv = (sc->sc_read)(sc, buf, TPM_HDRSIZE, &cnt, 0))) {
1389 		(sc->sc_end)(sc, UIO_READ, rv);
1390 		splx(s);
1391 		return rv;
1392 	}
1393 
1394 	len = (buf[2] << 24) | (buf[3] << 16) | (buf[4] << 8) | buf[5];
1395 #ifdef TPM_DEBUG
1396 	printf("tpmread: len %d, io count %d\n", len, uio->uio_resid);
1397 #endif
1398 	if (len > uio->uio_resid) {
1399 		rv = EIO;
1400 		(sc->sc_end)(sc, UIO_READ, rv);
1401 #ifdef TPM_DEBUG
1402 		printf("tpmread: bad residual io count 0x%x\n", uio->uio_resid);
1403 #endif
1404 		splx(s);
1405 		return rv;
1406 	}
1407 
1408 	/* Copy out header. */
1409 	if ((rv = uiomove((caddr_t)buf, cnt, uio))) {
1410 		(sc->sc_end)(sc, UIO_READ, rv);
1411 		splx(s);
1412 		return rv;
1413 	}
1414 
1415 	/* Get remaining part of the answer (if anything is left). */
1416 	for (len -= cnt, p = buf, n = sizeof(buf); len > 0; p = buf, len -= n,
1417 	    n = sizeof(buf)) {
1418 		n = MIN(n, len);
1419 #ifdef TPM_DEBUG
1420 		printf("tpmread: n %d len %d\n", n, len);
1421 #endif
1422 		if ((rv = (sc->sc_read)(sc, p, n, NULL, TPM_PARAM_SIZE))) {
1423 			(sc->sc_end)(sc, UIO_READ, rv);
1424 			splx(s);
1425 			return rv;
1426 		}
1427 		p += n;
1428 		if ((rv = uiomove((caddr_t)buf, p - buf, uio))) {
1429 			(sc->sc_end)(sc, UIO_READ, rv);
1430 			splx(s);
1431 			return rv;
1432 		}
1433 	}
1434 
1435 	rv = (sc->sc_end)(sc, UIO_READ, rv);
1436 	splx(s);
1437 	return rv;
1438 }
1439 
1440 int
1441 #ifdef __FreeBSD__
1442 tpmwrite(struct cdev *dev, struct uio *uio, int flags)
1443 #else
1444 tpmwrite(dev_t dev, struct uio *uio, int flags)
1445 #endif
1446 {
1447 	struct tpm_softc *sc = TPMSOFTC(dev);
1448 	u_int8_t buf[TPM_BUFSIZ];
1449 	int n, rv, s;
1450 
1451 	if (!sc)
1452 		return ENXIO;
1453 
1454 	s = spltty();
1455 
1456 #ifdef TPM_DEBUG
1457 	printf("tpmwrite: io count %d\n", uio->uio_resid);
1458 #endif
1459 
1460 	n = MIN(sizeof(buf), uio->uio_resid);
1461 	if ((rv = uiomove((caddr_t)buf, n, uio))) {
1462 		splx(s);
1463 		return rv;
1464 	}
1465 
1466 	if ((rv = (sc->sc_start)(sc, UIO_WRITE))) {
1467 		splx(s);
1468 		return rv;
1469 	}
1470 
1471 	if ((rv = (sc->sc_write(sc, buf, n)))) {
1472 		splx(s);
1473 		return rv;
1474 	}
1475 
1476 	rv = (sc->sc_end)(sc, UIO_WRITE, rv);
1477 	splx(s);
1478 	return rv;
1479 }
1480 
1481 int
1482 #ifdef __FreeBSD__
1483 tpmioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags,
1484     struct thread *td)
1485 #else
1486 tpmioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct proc *p)
1487 #endif
1488 {
1489 	return ENOTTY;
1490 }
1491