1/*
2 * Copyright (C) 2004 IBM Corporation
3 *
4 * Authors:
5 * Leendert van Doorn <leendert@watson.ibm.com>
6 * Dave Safford <safford@watson.ibm.com>
7 * Reiner Sailer <sailer@watson.ibm.com>
8 * Kylene Hall <kjhall@us.ibm.com>
9 *
10 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
11 *
12 * Device driver for TCG/TCPA TPM (trusted platform module).
13 * Specifications at www.trustedcomputinggroup.org
14 *
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License as
17 * published by the Free Software Foundation, version 2 of the
18 * License.
19 *
20 */
21
22#include <linux/platform_device.h>
23#include <linux/slab.h>
24#include "tpm.h"
25
26/* National definitions */
27enum tpm_nsc_addr{
28	TPM_NSC_IRQ = 0x07,
29	TPM_NSC_BASE0_HI = 0x60,
30	TPM_NSC_BASE0_LO = 0x61,
31	TPM_NSC_BASE1_HI = 0x62,
32	TPM_NSC_BASE1_LO = 0x63
33};
34
35enum tpm_nsc_index {
36	NSC_LDN_INDEX = 0x07,
37	NSC_SID_INDEX = 0x20,
38	NSC_LDC_INDEX = 0x30,
39	NSC_DIO_INDEX = 0x60,
40	NSC_CIO_INDEX = 0x62,
41	NSC_IRQ_INDEX = 0x70,
42	NSC_ITS_INDEX = 0x71
43};
44
45enum tpm_nsc_status_loc {
46	NSC_STATUS = 0x01,
47	NSC_COMMAND = 0x01,
48	NSC_DATA = 0x00
49};
50
51/* status bits */
52enum tpm_nsc_status {
53	NSC_STATUS_OBF = 0x01,	/* output buffer full */
54	NSC_STATUS_IBF = 0x02,	/* input buffer full */
55	NSC_STATUS_F0 = 0x04,	/* F0 */
56	NSC_STATUS_A2 = 0x08,	/* A2 */
57	NSC_STATUS_RDY = 0x10,	/* ready to receive command */
58	NSC_STATUS_IBR = 0x20	/* ready to receive data */
59};
60
61/* command bits */
62enum tpm_nsc_cmd_mode {
63	NSC_COMMAND_NORMAL = 0x01,	/* normal mode */
64	NSC_COMMAND_EOC = 0x03,
65	NSC_COMMAND_CANCEL = 0x22
66};
67/*
68 * Wait for a certain status to appear
69 */
70static int wait_for_stat(struct tpm_chip *chip, u8 mask, u8 val, u8 * data)
71{
72	unsigned long stop;
73
74	/* status immediately available check */
75	*data = inb(chip->vendor.base + NSC_STATUS);
76	if ((*data & mask) == val)
77		return 0;
78
79	/* wait for status */
80	stop = jiffies + 10 * HZ;
81	do {
82		msleep(TPM_TIMEOUT);
83		*data = inb(chip->vendor.base + 1);
84		if ((*data & mask) == val)
85			return 0;
86	}
87	while (time_before(jiffies, stop));
88
89	return -EBUSY;
90}
91
92static int nsc_wait_for_ready(struct tpm_chip *chip)
93{
94	int status;
95	unsigned long stop;
96
97	/* status immediately available check */
98	status = inb(chip->vendor.base + NSC_STATUS);
99	if (status & NSC_STATUS_OBF)
100		status = inb(chip->vendor.base + NSC_DATA);
101	if (status & NSC_STATUS_RDY)
102		return 0;
103
104	/* wait for status */
105	stop = jiffies + 100;
106	do {
107		msleep(TPM_TIMEOUT);
108		status = inb(chip->vendor.base + NSC_STATUS);
109		if (status & NSC_STATUS_OBF)
110			status = inb(chip->vendor.base + NSC_DATA);
111		if (status & NSC_STATUS_RDY)
112			return 0;
113	}
114	while (time_before(jiffies, stop));
115
116	dev_info(chip->pdev, "wait for ready failed\n");
117	return -EBUSY;
118}
119
120
121static int tpm_nsc_recv(struct tpm_chip *chip, u8 * buf, size_t count)
122{
123	u8 *buffer = buf;
124	u8 data, *p;
125	u32 size;
126	__be32 *native_size;
127
128	if (count < 6)
129		return -EIO;
130
131	if (wait_for_stat(chip, NSC_STATUS_F0, NSC_STATUS_F0, &data) < 0) {
132		dev_err(chip->pdev, "F0 timeout\n");
133		return -EIO;
134	}
135	if ((data =
136	     inb(chip->vendor.base + NSC_DATA)) != NSC_COMMAND_NORMAL) {
137		dev_err(chip->pdev, "not in normal mode (0x%x)\n",
138			data);
139		return -EIO;
140	}
141
142	/* read the whole packet */
143	for (p = buffer; p < &buffer[count]; p++) {
144		if (wait_for_stat
145		    (chip, NSC_STATUS_OBF, NSC_STATUS_OBF, &data) < 0) {
146			dev_err(chip->pdev,
147				"OBF timeout (while reading data)\n");
148			return -EIO;
149		}
150		if (data & NSC_STATUS_F0)
151			break;
152		*p = inb(chip->vendor.base + NSC_DATA);
153	}
154
155	if ((data & NSC_STATUS_F0) == 0 &&
156	(wait_for_stat(chip, NSC_STATUS_F0, NSC_STATUS_F0, &data) < 0)) {
157		dev_err(chip->pdev, "F0 not set\n");
158		return -EIO;
159	}
160	if ((data = inb(chip->vendor.base + NSC_DATA)) != NSC_COMMAND_EOC) {
161		dev_err(chip->pdev,
162			"expected end of command(0x%x)\n", data);
163		return -EIO;
164	}
165
166	native_size = (__force __be32 *) (buf + 2);
167	size = be32_to_cpu(*native_size);
168
169	if (count < size)
170		return -EIO;
171
172	return size;
173}
174
175static int tpm_nsc_send(struct tpm_chip *chip, u8 * buf, size_t count)
176{
177	u8 data;
178	int i;
179
180	/*
181	 * If we hit the chip with back to back commands it locks up
182	 * and never set IBF. Hitting it with this "hammer" seems to
183	 * fix it. Not sure why this is needed, we followed the flow
184	 * chart in the manual to the letter.
185	 */
186	outb(NSC_COMMAND_CANCEL, chip->vendor.base + NSC_COMMAND);
187
188	if (nsc_wait_for_ready(chip) != 0)
189		return -EIO;
190
191	if (wait_for_stat(chip, NSC_STATUS_IBF, 0, &data) < 0) {
192		dev_err(chip->pdev, "IBF timeout\n");
193		return -EIO;
194	}
195
196	outb(NSC_COMMAND_NORMAL, chip->vendor.base + NSC_COMMAND);
197	if (wait_for_stat(chip, NSC_STATUS_IBR, NSC_STATUS_IBR, &data) < 0) {
198		dev_err(chip->pdev, "IBR timeout\n");
199		return -EIO;
200	}
201
202	for (i = 0; i < count; i++) {
203		if (wait_for_stat(chip, NSC_STATUS_IBF, 0, &data) < 0) {
204			dev_err(chip->pdev,
205				"IBF timeout (while writing data)\n");
206			return -EIO;
207		}
208		outb(buf[i], chip->vendor.base + NSC_DATA);
209	}
210
211	if (wait_for_stat(chip, NSC_STATUS_IBF, 0, &data) < 0) {
212		dev_err(chip->pdev, "IBF timeout\n");
213		return -EIO;
214	}
215	outb(NSC_COMMAND_EOC, chip->vendor.base + NSC_COMMAND);
216
217	return count;
218}
219
220static void tpm_nsc_cancel(struct tpm_chip *chip)
221{
222	outb(NSC_COMMAND_CANCEL, chip->vendor.base + NSC_COMMAND);
223}
224
225static u8 tpm_nsc_status(struct tpm_chip *chip)
226{
227	return inb(chip->vendor.base + NSC_STATUS);
228}
229
230static bool tpm_nsc_req_canceled(struct tpm_chip *chip, u8 status)
231{
232	return (status == NSC_STATUS_RDY);
233}
234
235static const struct tpm_class_ops tpm_nsc = {
236	.recv = tpm_nsc_recv,
237	.send = tpm_nsc_send,
238	.cancel = tpm_nsc_cancel,
239	.status = tpm_nsc_status,
240	.req_complete_mask = NSC_STATUS_OBF,
241	.req_complete_val = NSC_STATUS_OBF,
242	.req_canceled = tpm_nsc_req_canceled,
243};
244
245static struct platform_device *pdev = NULL;
246
247static void tpm_nsc_remove(struct device *dev)
248{
249	struct tpm_chip *chip = dev_get_drvdata(dev);
250
251	tpm_chip_unregister(chip);
252	release_region(chip->vendor.base, 2);
253}
254
255static SIMPLE_DEV_PM_OPS(tpm_nsc_pm, tpm_pm_suspend, tpm_pm_resume);
256
257static struct platform_driver nsc_drv = {
258	.driver          = {
259		.name    = "tpm_nsc",
260		.pm      = &tpm_nsc_pm,
261	},
262};
263
264static int __init init_nsc(void)
265{
266	int rc = 0;
267	int lo, hi, err;
268	int nscAddrBase = TPM_ADDR;
269	struct tpm_chip *chip;
270	unsigned long base;
271
272	/* verify that it is a National part (SID) */
273	if (tpm_read_index(TPM_ADDR, NSC_SID_INDEX) != 0xEF) {
274		nscAddrBase = (tpm_read_index(TPM_SUPERIO_ADDR, 0x2C)<<8)|
275			(tpm_read_index(TPM_SUPERIO_ADDR, 0x2B)&0xFE);
276		if (tpm_read_index(nscAddrBase, NSC_SID_INDEX) != 0xF6)
277			return -ENODEV;
278	}
279
280	err = platform_driver_register(&nsc_drv);
281	if (err)
282		return err;
283
284	hi = tpm_read_index(nscAddrBase, TPM_NSC_BASE0_HI);
285	lo = tpm_read_index(nscAddrBase, TPM_NSC_BASE0_LO);
286	base = (hi<<8) | lo;
287
288	/* enable the DPM module */
289	tpm_write_index(nscAddrBase, NSC_LDC_INDEX, 0x01);
290
291	pdev = platform_device_alloc("tpm_nscl0", -1);
292	if (!pdev) {
293		rc = -ENOMEM;
294		goto err_unreg_drv;
295	}
296
297	pdev->num_resources = 0;
298	pdev->dev.driver = &nsc_drv.driver;
299	pdev->dev.release = tpm_nsc_remove;
300
301	if ((rc = platform_device_add(pdev)) < 0)
302		goto err_put_dev;
303
304	if (request_region(base, 2, "tpm_nsc0") == NULL ) {
305		rc = -EBUSY;
306		goto err_del_dev;
307	}
308
309	chip = tpmm_chip_alloc(&pdev->dev, &tpm_nsc);
310	if (IS_ERR(chip)) {
311		rc = -ENODEV;
312		goto err_rel_reg;
313	}
314
315	rc = tpm_chip_register(chip);
316	if (rc)
317		goto err_rel_reg;
318
319	dev_dbg(&pdev->dev, "NSC TPM detected\n");
320	dev_dbg(&pdev->dev,
321		"NSC LDN 0x%x, SID 0x%x, SRID 0x%x\n",
322		tpm_read_index(nscAddrBase,0x07), tpm_read_index(nscAddrBase,0x20),
323		tpm_read_index(nscAddrBase,0x27));
324	dev_dbg(&pdev->dev,
325		"NSC SIOCF1 0x%x SIOCF5 0x%x SIOCF6 0x%x SIOCF8 0x%x\n",
326		tpm_read_index(nscAddrBase,0x21), tpm_read_index(nscAddrBase,0x25),
327		tpm_read_index(nscAddrBase,0x26), tpm_read_index(nscAddrBase,0x28));
328	dev_dbg(&pdev->dev, "NSC IO Base0 0x%x\n",
329		(tpm_read_index(nscAddrBase,0x60) << 8) | tpm_read_index(nscAddrBase,0x61));
330	dev_dbg(&pdev->dev, "NSC IO Base1 0x%x\n",
331		(tpm_read_index(nscAddrBase,0x62) << 8) | tpm_read_index(nscAddrBase,0x63));
332	dev_dbg(&pdev->dev, "NSC Interrupt number and wakeup 0x%x\n",
333		tpm_read_index(nscAddrBase,0x70));
334	dev_dbg(&pdev->dev, "NSC IRQ type select 0x%x\n",
335		tpm_read_index(nscAddrBase,0x71));
336	dev_dbg(&pdev->dev,
337		"NSC DMA channel select0 0x%x, select1 0x%x\n",
338		tpm_read_index(nscAddrBase,0x74), tpm_read_index(nscAddrBase,0x75));
339	dev_dbg(&pdev->dev,
340		"NSC Config "
341		"0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x\n",
342		tpm_read_index(nscAddrBase,0xF0), tpm_read_index(nscAddrBase,0xF1),
343		tpm_read_index(nscAddrBase,0xF2), tpm_read_index(nscAddrBase,0xF3),
344		tpm_read_index(nscAddrBase,0xF4), tpm_read_index(nscAddrBase,0xF5),
345		tpm_read_index(nscAddrBase,0xF6), tpm_read_index(nscAddrBase,0xF7),
346		tpm_read_index(nscAddrBase,0xF8), tpm_read_index(nscAddrBase,0xF9));
347
348	dev_info(&pdev->dev,
349		 "NSC TPM revision %d\n",
350		 tpm_read_index(nscAddrBase, 0x27) & 0x1F);
351
352	chip->vendor.base = base;
353
354	return 0;
355
356err_rel_reg:
357	release_region(base, 2);
358err_del_dev:
359	platform_device_del(pdev);
360err_put_dev:
361	platform_device_put(pdev);
362err_unreg_drv:
363	platform_driver_unregister(&nsc_drv);
364	return rc;
365}
366
367static void __exit cleanup_nsc(void)
368{
369	if (pdev) {
370		tpm_nsc_remove(&pdev->dev);
371		platform_device_unregister(pdev);
372	}
373
374	platform_driver_unregister(&nsc_drv);
375}
376
377module_init(init_nsc);
378module_exit(cleanup_nsc);
379
380MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
381MODULE_DESCRIPTION("TPM Driver");
382MODULE_VERSION("2.0");
383MODULE_LICENSE("GPL");
384