1/*
2 * Description:
3 * Device Driver for the Infineon Technologies
4 * SLD 9630 TT 1.1 and SLB 9635 TT 1.2 Trusted Platform Module
5 * Specifications at www.trustedcomputinggroup.org
6 *
7 * Copyright (C) 2005, Marcel Selhorst <tpmdd@selhorst.net>
8 * Sirrix AG - security technologies <tpmdd@sirrix.com> and
9 * Applied Data Security Group, Ruhr-University Bochum, Germany
10 * Project-Homepage: http://www.trust.rub.de/projects/linux-device-driver-infineon-tpm/
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License as
14 * published by the Free Software Foundation, version 2 of the
15 * License.
16 */
17
18#include <linux/init.h>
19#include <linux/pnp.h>
20#include "tpm.h"
21
22/* Infineon specific definitions */
23/* maximum number of WTX-packages */
24#define	TPM_MAX_WTX_PACKAGES 	50
25/* msleep-Time for WTX-packages */
26#define	TPM_WTX_MSLEEP_TIME 	20
27/* msleep-Time --> Interval to check status register */
28#define	TPM_MSLEEP_TIME 	3
29/* gives number of max. msleep()-calls before throwing timeout */
30#define	TPM_MAX_TRIES		5000
31#define	TPM_INFINEON_DEV_VEN_VALUE	0x15D1
32
33#define TPM_INF_IO_PORT		0x0
34#define TPM_INF_IO_MEM		0x1
35
36#define TPM_INF_ADDR		0x0
37#define TPM_INF_DATA		0x1
38
39struct tpm_inf_dev {
40	int iotype;
41
42	void __iomem *mem_base;	/* MMIO ioremap'd addr */
43	unsigned long map_base;	/* phys MMIO base */
44	unsigned long map_size;	/* MMIO region size */
45	unsigned int index_off;	/* index register offset */
46
47	unsigned int data_regs;	/* Data registers */
48	unsigned int data_size;
49
50	unsigned int config_port;	/* IO Port config index reg */
51	unsigned int config_size;
52};
53
54static struct tpm_inf_dev tpm_dev;
55
56static inline void tpm_data_out(unsigned char data, unsigned char offset)
57{
58	if (tpm_dev.iotype == TPM_INF_IO_PORT)
59		outb(data, tpm_dev.data_regs + offset);
60	else
61		writeb(data, tpm_dev.mem_base + tpm_dev.data_regs + offset);
62}
63
64static inline unsigned char tpm_data_in(unsigned char offset)
65{
66	if (tpm_dev.iotype == TPM_INF_IO_PORT)
67		return inb(tpm_dev.data_regs + offset);
68	else
69		return readb(tpm_dev.mem_base + tpm_dev.data_regs + offset);
70}
71
72static inline void tpm_config_out(unsigned char data, unsigned char offset)
73{
74	if (tpm_dev.iotype == TPM_INF_IO_PORT)
75		outb(data, tpm_dev.config_port + offset);
76	else
77		writeb(data, tpm_dev.mem_base + tpm_dev.index_off + offset);
78}
79
80static inline unsigned char tpm_config_in(unsigned char offset)
81{
82	if (tpm_dev.iotype == TPM_INF_IO_PORT)
83		return inb(tpm_dev.config_port + offset);
84	else
85		return readb(tpm_dev.mem_base + tpm_dev.index_off + offset);
86}
87
88/* TPM header definitions */
89enum infineon_tpm_header {
90	TPM_VL_VER = 0x01,
91	TPM_VL_CHANNEL_CONTROL = 0x07,
92	TPM_VL_CHANNEL_PERSONALISATION = 0x0A,
93	TPM_VL_CHANNEL_TPM = 0x0B,
94	TPM_VL_CONTROL = 0x00,
95	TPM_INF_NAK = 0x15,
96	TPM_CTRL_WTX = 0x10,
97	TPM_CTRL_WTX_ABORT = 0x18,
98	TPM_CTRL_WTX_ABORT_ACK = 0x18,
99	TPM_CTRL_ERROR = 0x20,
100	TPM_CTRL_CHAININGACK = 0x40,
101	TPM_CTRL_CHAINING = 0x80,
102	TPM_CTRL_DATA = 0x04,
103	TPM_CTRL_DATA_CHA = 0x84,
104	TPM_CTRL_DATA_CHA_ACK = 0xC4
105};
106
107enum infineon_tpm_register {
108	WRFIFO = 0x00,
109	RDFIFO = 0x01,
110	STAT = 0x02,
111	CMD = 0x03
112};
113
114enum infineon_tpm_command_bits {
115	CMD_DIS = 0x00,
116	CMD_LP = 0x01,
117	CMD_RES = 0x02,
118	CMD_IRQC = 0x06
119};
120
121enum infineon_tpm_status_bits {
122	STAT_XFE = 0x00,
123	STAT_LPA = 0x01,
124	STAT_FOK = 0x02,
125	STAT_TOK = 0x03,
126	STAT_IRQA = 0x06,
127	STAT_RDA = 0x07
128};
129
130/* some outgoing values */
131enum infineon_tpm_values {
132	CHIP_ID1 = 0x20,
133	CHIP_ID2 = 0x21,
134	TPM_DAR = 0x30,
135	RESET_LP_IRQC_DISABLE = 0x41,
136	ENABLE_REGISTER_PAIR = 0x55,
137	IOLIMH = 0x60,
138	IOLIML = 0x61,
139	DISABLE_REGISTER_PAIR = 0xAA,
140	IDVENL = 0xF1,
141	IDVENH = 0xF2,
142	IDPDL = 0xF3,
143	IDPDH = 0xF4
144};
145
146static int number_of_wtx;
147
148static int empty_fifo(struct tpm_chip *chip, int clear_wrfifo)
149{
150	int status;
151	int check = 0;
152	int i;
153
154	if (clear_wrfifo) {
155		for (i = 0; i < 4096; i++) {
156			status = tpm_data_in(WRFIFO);
157			if (status == 0xff) {
158				if (check == 5)
159					break;
160				else
161					check++;
162			}
163		}
164	}
165	/* Note: The values which are currently in the FIFO of the TPM
166	   are thrown away since there is no usage for them. Usually,
167	   this has nothing to say, since the TPM will give its answer
168	   immediately or will be aborted anyway, so the data here is
169	   usually garbage and useless.
170	   We have to clean this, because the next communication with
171	   the TPM would be rubbish, if there is still some old data
172	   in the Read FIFO.
173	 */
174	i = 0;
175	do {
176		status = tpm_data_in(RDFIFO);
177		status = tpm_data_in(STAT);
178		i++;
179		if (i == TPM_MAX_TRIES)
180			return -EIO;
181	} while ((status & (1 << STAT_RDA)) != 0);
182	return 0;
183}
184
185static int wait(struct tpm_chip *chip, int wait_for_bit)
186{
187	int status;
188	int i;
189	for (i = 0; i < TPM_MAX_TRIES; i++) {
190		status = tpm_data_in(STAT);
191		/* check the status-register if wait_for_bit is set */
192		if (status & 1 << wait_for_bit)
193			break;
194		msleep(TPM_MSLEEP_TIME);
195	}
196	if (i == TPM_MAX_TRIES) {	/* timeout occurs */
197		if (wait_for_bit == STAT_XFE)
198			dev_err(chip->pdev, "Timeout in wait(STAT_XFE)\n");
199		if (wait_for_bit == STAT_RDA)
200			dev_err(chip->pdev, "Timeout in wait(STAT_RDA)\n");
201		return -EIO;
202	}
203	return 0;
204};
205
206static void wait_and_send(struct tpm_chip *chip, u8 sendbyte)
207{
208	wait(chip, STAT_XFE);
209	tpm_data_out(sendbyte, WRFIFO);
210}
211
212    /* Note: WTX means Waiting-Time-Extension. Whenever the TPM needs more
213       calculation time, it sends a WTX-package, which has to be acknowledged
214       or aborted. This usually occurs if you are hammering the TPM with key
215       creation. Set the maximum number of WTX-packages in the definitions
216       above, if the number is reached, the waiting-time will be denied
217       and the TPM command has to be resend.
218     */
219
220static void tpm_wtx(struct tpm_chip *chip)
221{
222	number_of_wtx++;
223	dev_info(chip->pdev, "Granting WTX (%02d / %02d)\n",
224		 number_of_wtx, TPM_MAX_WTX_PACKAGES);
225	wait_and_send(chip, TPM_VL_VER);
226	wait_and_send(chip, TPM_CTRL_WTX);
227	wait_and_send(chip, 0x00);
228	wait_and_send(chip, 0x00);
229	msleep(TPM_WTX_MSLEEP_TIME);
230}
231
232static void tpm_wtx_abort(struct tpm_chip *chip)
233{
234	dev_info(chip->pdev, "Aborting WTX\n");
235	wait_and_send(chip, TPM_VL_VER);
236	wait_and_send(chip, TPM_CTRL_WTX_ABORT);
237	wait_and_send(chip, 0x00);
238	wait_and_send(chip, 0x00);
239	number_of_wtx = 0;
240	msleep(TPM_WTX_MSLEEP_TIME);
241}
242
243static int tpm_inf_recv(struct tpm_chip *chip, u8 * buf, size_t count)
244{
245	int i;
246	int ret;
247	u32 size = 0;
248	number_of_wtx = 0;
249
250recv_begin:
251	/* start receiving header */
252	for (i = 0; i < 4; i++) {
253		ret = wait(chip, STAT_RDA);
254		if (ret)
255			return -EIO;
256		buf[i] = tpm_data_in(RDFIFO);
257	}
258
259	if (buf[0] != TPM_VL_VER) {
260		dev_err(chip->pdev,
261			"Wrong transport protocol implementation!\n");
262		return -EIO;
263	}
264
265	if (buf[1] == TPM_CTRL_DATA) {
266		/* size of the data received */
267		size = ((buf[2] << 8) | buf[3]);
268
269		for (i = 0; i < size; i++) {
270			wait(chip, STAT_RDA);
271			buf[i] = tpm_data_in(RDFIFO);
272		}
273
274		if ((size == 0x6D00) && (buf[1] == 0x80)) {
275			dev_err(chip->pdev, "Error handling on vendor layer!\n");
276			return -EIO;
277		}
278
279		for (i = 0; i < size; i++)
280			buf[i] = buf[i + 6];
281
282		size = size - 6;
283		return size;
284	}
285
286	if (buf[1] == TPM_CTRL_WTX) {
287		dev_info(chip->pdev, "WTX-package received\n");
288		if (number_of_wtx < TPM_MAX_WTX_PACKAGES) {
289			tpm_wtx(chip);
290			goto recv_begin;
291		} else {
292			tpm_wtx_abort(chip);
293			goto recv_begin;
294		}
295	}
296
297	if (buf[1] == TPM_CTRL_WTX_ABORT_ACK) {
298		dev_info(chip->pdev, "WTX-abort acknowledged\n");
299		return size;
300	}
301
302	if (buf[1] == TPM_CTRL_ERROR) {
303		dev_err(chip->pdev, "ERROR-package received:\n");
304		if (buf[4] == TPM_INF_NAK)
305			dev_err(chip->pdev,
306				"-> Negative acknowledgement"
307				" - retransmit command!\n");
308		return -EIO;
309	}
310	return -EIO;
311}
312
313static int tpm_inf_send(struct tpm_chip *chip, u8 * buf, size_t count)
314{
315	int i;
316	int ret;
317	u8 count_high, count_low, count_4, count_3, count_2, count_1;
318
319	/* Disabling Reset, LP and IRQC */
320	tpm_data_out(RESET_LP_IRQC_DISABLE, CMD);
321
322	ret = empty_fifo(chip, 1);
323	if (ret) {
324		dev_err(chip->pdev, "Timeout while clearing FIFO\n");
325		return -EIO;
326	}
327
328	ret = wait(chip, STAT_XFE);
329	if (ret)
330		return -EIO;
331
332	count_4 = (count & 0xff000000) >> 24;
333	count_3 = (count & 0x00ff0000) >> 16;
334	count_2 = (count & 0x0000ff00) >> 8;
335	count_1 = (count & 0x000000ff);
336	count_high = ((count + 6) & 0xffffff00) >> 8;
337	count_low = ((count + 6) & 0x000000ff);
338
339	/* Sending Header */
340	wait_and_send(chip, TPM_VL_VER);
341	wait_and_send(chip, TPM_CTRL_DATA);
342	wait_and_send(chip, count_high);
343	wait_and_send(chip, count_low);
344
345	/* Sending Data Header */
346	wait_and_send(chip, TPM_VL_VER);
347	wait_and_send(chip, TPM_VL_CHANNEL_TPM);
348	wait_and_send(chip, count_4);
349	wait_and_send(chip, count_3);
350	wait_and_send(chip, count_2);
351	wait_and_send(chip, count_1);
352
353	/* Sending Data */
354	for (i = 0; i < count; i++) {
355		wait_and_send(chip, buf[i]);
356	}
357	return count;
358}
359
360static void tpm_inf_cancel(struct tpm_chip *chip)
361{
362	/*
363	   Since we are using the legacy mode to communicate
364	   with the TPM, we have no cancel functions, but have
365	   a workaround for interrupting the TPM through WTX.
366	 */
367}
368
369static u8 tpm_inf_status(struct tpm_chip *chip)
370{
371	return tpm_data_in(STAT);
372}
373
374static const struct tpm_class_ops tpm_inf = {
375	.recv = tpm_inf_recv,
376	.send = tpm_inf_send,
377	.cancel = tpm_inf_cancel,
378	.status = tpm_inf_status,
379	.req_complete_mask = 0,
380	.req_complete_val = 0,
381};
382
383static const struct pnp_device_id tpm_inf_pnp_tbl[] = {
384	/* Infineon TPMs */
385	{"IFX0101", 0},
386	{"IFX0102", 0},
387	{"", 0}
388};
389
390MODULE_DEVICE_TABLE(pnp, tpm_inf_pnp_tbl);
391
392static int tpm_inf_pnp_probe(struct pnp_dev *dev,
393				       const struct pnp_device_id *dev_id)
394{
395	int rc = 0;
396	u8 iol, ioh;
397	int vendorid[2];
398	int version[2];
399	int productid[2];
400	char chipname[20];
401	struct tpm_chip *chip;
402
403	/* read IO-ports through PnP */
404	if (pnp_port_valid(dev, 0) && pnp_port_valid(dev, 1) &&
405	    !(pnp_port_flags(dev, 0) & IORESOURCE_DISABLED)) {
406
407		tpm_dev.iotype = TPM_INF_IO_PORT;
408
409		tpm_dev.config_port = pnp_port_start(dev, 0);
410		tpm_dev.config_size = pnp_port_len(dev, 0);
411		tpm_dev.data_regs = pnp_port_start(dev, 1);
412		tpm_dev.data_size = pnp_port_len(dev, 1);
413		if ((tpm_dev.data_size < 4) || (tpm_dev.config_size < 2)) {
414			rc = -EINVAL;
415			goto err_last;
416		}
417		dev_info(&dev->dev, "Found %s with ID %s\n",
418			 dev->name, dev_id->id);
419		if (!((tpm_dev.data_regs >> 8) & 0xff)) {
420			rc = -EINVAL;
421			goto err_last;
422		}
423		/* publish my base address and request region */
424		if (request_region(tpm_dev.data_regs, tpm_dev.data_size,
425				   "tpm_infineon0") == NULL) {
426			rc = -EINVAL;
427			goto err_last;
428		}
429		if (request_region(tpm_dev.config_port, tpm_dev.config_size,
430				   "tpm_infineon0") == NULL) {
431			release_region(tpm_dev.data_regs, tpm_dev.data_size);
432			rc = -EINVAL;
433			goto err_last;
434		}
435	} else if (pnp_mem_valid(dev, 0) &&
436		   !(pnp_mem_flags(dev, 0) & IORESOURCE_DISABLED)) {
437
438		tpm_dev.iotype = TPM_INF_IO_MEM;
439
440		tpm_dev.map_base = pnp_mem_start(dev, 0);
441		tpm_dev.map_size = pnp_mem_len(dev, 0);
442
443		dev_info(&dev->dev, "Found %s with ID %s\n",
444			 dev->name, dev_id->id);
445
446		/* publish my base address and request region */
447		if (request_mem_region(tpm_dev.map_base, tpm_dev.map_size,
448				       "tpm_infineon0") == NULL) {
449			rc = -EINVAL;
450			goto err_last;
451		}
452
453		tpm_dev.mem_base = ioremap(tpm_dev.map_base, tpm_dev.map_size);
454		if (tpm_dev.mem_base == NULL) {
455			release_mem_region(tpm_dev.map_base, tpm_dev.map_size);
456			rc = -EINVAL;
457			goto err_last;
458		}
459
460		/*
461		 * The only known MMIO based Infineon TPM system provides
462		 * a single large mem region with the device config
463		 * registers at the default TPM_ADDR.  The data registers
464		 * seem like they could be placed anywhere within the MMIO
465		 * region, but lets just put them at zero offset.
466		 */
467		tpm_dev.index_off = TPM_ADDR;
468		tpm_dev.data_regs = 0x0;
469	} else {
470		rc = -EINVAL;
471		goto err_last;
472	}
473
474	/* query chip for its vendor, its version number a.s.o. */
475	tpm_config_out(ENABLE_REGISTER_PAIR, TPM_INF_ADDR);
476	tpm_config_out(IDVENL, TPM_INF_ADDR);
477	vendorid[1] = tpm_config_in(TPM_INF_DATA);
478	tpm_config_out(IDVENH, TPM_INF_ADDR);
479	vendorid[0] = tpm_config_in(TPM_INF_DATA);
480	tpm_config_out(IDPDL, TPM_INF_ADDR);
481	productid[1] = tpm_config_in(TPM_INF_DATA);
482	tpm_config_out(IDPDH, TPM_INF_ADDR);
483	productid[0] = tpm_config_in(TPM_INF_DATA);
484	tpm_config_out(CHIP_ID1, TPM_INF_ADDR);
485	version[1] = tpm_config_in(TPM_INF_DATA);
486	tpm_config_out(CHIP_ID2, TPM_INF_ADDR);
487	version[0] = tpm_config_in(TPM_INF_DATA);
488
489	switch ((productid[0] << 8) | productid[1]) {
490	case 6:
491		snprintf(chipname, sizeof(chipname), " (SLD 9630 TT 1.1)");
492		break;
493	case 11:
494		snprintf(chipname, sizeof(chipname), " (SLB 9635 TT 1.2)");
495		break;
496	default:
497		snprintf(chipname, sizeof(chipname), " (unknown chip)");
498		break;
499	}
500
501	if ((vendorid[0] << 8 | vendorid[1]) == (TPM_INFINEON_DEV_VEN_VALUE)) {
502
503		/* configure TPM with IO-ports */
504		tpm_config_out(IOLIMH, TPM_INF_ADDR);
505		tpm_config_out((tpm_dev.data_regs >> 8) & 0xff, TPM_INF_DATA);
506		tpm_config_out(IOLIML, TPM_INF_ADDR);
507		tpm_config_out((tpm_dev.data_regs & 0xff), TPM_INF_DATA);
508
509		/* control if IO-ports are set correctly */
510		tpm_config_out(IOLIMH, TPM_INF_ADDR);
511		ioh = tpm_config_in(TPM_INF_DATA);
512		tpm_config_out(IOLIML, TPM_INF_ADDR);
513		iol = tpm_config_in(TPM_INF_DATA);
514
515		if ((ioh << 8 | iol) != tpm_dev.data_regs) {
516			dev_err(&dev->dev,
517				"Could not set IO-data registers to 0x%x\n",
518				tpm_dev.data_regs);
519			rc = -EIO;
520			goto err_release_region;
521		}
522
523		/* activate register */
524		tpm_config_out(TPM_DAR, TPM_INF_ADDR);
525		tpm_config_out(0x01, TPM_INF_DATA);
526		tpm_config_out(DISABLE_REGISTER_PAIR, TPM_INF_ADDR);
527
528		/* disable RESET, LP and IRQC */
529		tpm_data_out(RESET_LP_IRQC_DISABLE, CMD);
530
531		/* Finally, we're done, print some infos */
532		dev_info(&dev->dev, "TPM found: "
533			 "config base 0x%lx, "
534			 "data base 0x%lx, "
535			 "chip version 0x%02x%02x, "
536			 "vendor id 0x%x%x (Infineon), "
537			 "product id 0x%02x%02x"
538			 "%s\n",
539			 tpm_dev.iotype == TPM_INF_IO_PORT ?
540			 tpm_dev.config_port :
541			 tpm_dev.map_base + tpm_dev.index_off,
542			 tpm_dev.iotype == TPM_INF_IO_PORT ?
543			 tpm_dev.data_regs :
544			 tpm_dev.map_base + tpm_dev.data_regs,
545			 version[0], version[1],
546			 vendorid[0], vendorid[1],
547			 productid[0], productid[1], chipname);
548
549		chip = tpmm_chip_alloc(&dev->dev, &tpm_inf);
550		if (IS_ERR(chip)) {
551			rc = PTR_ERR(chip);
552			goto err_release_region;
553		}
554
555		rc = tpm_chip_register(chip);
556		if (rc)
557			goto err_release_region;
558
559		return 0;
560	} else {
561		rc = -ENODEV;
562		goto err_release_region;
563	}
564
565err_release_region:
566	if (tpm_dev.iotype == TPM_INF_IO_PORT) {
567		release_region(tpm_dev.data_regs, tpm_dev.data_size);
568		release_region(tpm_dev.config_port, tpm_dev.config_size);
569	} else {
570		iounmap(tpm_dev.mem_base);
571		release_mem_region(tpm_dev.map_base, tpm_dev.map_size);
572	}
573
574err_last:
575	return rc;
576}
577
578static void tpm_inf_pnp_remove(struct pnp_dev *dev)
579{
580	struct tpm_chip *chip = pnp_get_drvdata(dev);
581
582	tpm_chip_unregister(chip);
583
584	if (tpm_dev.iotype == TPM_INF_IO_PORT) {
585		release_region(tpm_dev.data_regs, tpm_dev.data_size);
586		release_region(tpm_dev.config_port,
587			       tpm_dev.config_size);
588	} else {
589		iounmap(tpm_dev.mem_base);
590		release_mem_region(tpm_dev.map_base, tpm_dev.map_size);
591	}
592}
593
594#ifdef CONFIG_PM_SLEEP
595static int tpm_inf_resume(struct device *dev)
596{
597	/* Re-configure TPM after suspending */
598	tpm_config_out(ENABLE_REGISTER_PAIR, TPM_INF_ADDR);
599	tpm_config_out(IOLIMH, TPM_INF_ADDR);
600	tpm_config_out((tpm_dev.data_regs >> 8) & 0xff, TPM_INF_DATA);
601	tpm_config_out(IOLIML, TPM_INF_ADDR);
602	tpm_config_out((tpm_dev.data_regs & 0xff), TPM_INF_DATA);
603	/* activate register */
604	tpm_config_out(TPM_DAR, TPM_INF_ADDR);
605	tpm_config_out(0x01, TPM_INF_DATA);
606	tpm_config_out(DISABLE_REGISTER_PAIR, TPM_INF_ADDR);
607	/* disable RESET, LP and IRQC */
608	tpm_data_out(RESET_LP_IRQC_DISABLE, CMD);
609	return tpm_pm_resume(dev);
610}
611#endif
612static SIMPLE_DEV_PM_OPS(tpm_inf_pm, tpm_pm_suspend, tpm_inf_resume);
613
614static struct pnp_driver tpm_inf_pnp_driver = {
615	.name = "tpm_inf_pnp",
616	.id_table = tpm_inf_pnp_tbl,
617	.probe = tpm_inf_pnp_probe,
618	.remove = tpm_inf_pnp_remove,
619	.driver = {
620		.pm = &tpm_inf_pm,
621	}
622};
623
624module_pnp_driver(tpm_inf_pnp_driver);
625
626MODULE_AUTHOR("Marcel Selhorst <tpmdd@sirrix.com>");
627MODULE_DESCRIPTION("Driver for Infineon TPM SLD 9630 TT 1.1 / SLB 9635 TT 1.2");
628MODULE_VERSION("1.9.2");
629MODULE_LICENSE("GPL");
630