drivers/char/tpm/tpm_nsc.c

   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 */
  27 enum 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
  35 enum 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
  45 enum tpm_nsc_status_loc {
  46         NSC_STATUS = 0x01,
  47         NSC_COMMAND = 0x01,
  48         NSC_DATA = 0x00
  49 };
  50
  51 /* status bits */
  52 enum 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 */
  62 enum 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  */
  70 static 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
  92 static 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->dev, "wait for ready failed\n");
 117         return -EBUSY;
 118 }
 119
 120
 121 static 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->dev, "F0 timeout\n");
 133                 return -EIO;
 134         }
 135         if ((data =
 136              inb(chip->vendor.base + NSC_DATA)) != NSC_COMMAND_NORMAL) {
 137                 dev_err(chip->dev, "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->dev,
 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->dev, "F0 not set\n");
 158                 return -EIO;
 159         }
 160         if ((data = inb(chip->vendor.base + NSC_DATA)) != NSC_COMMAND_EOC) {
 161                 dev_err(chip->dev,
 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
 175 static 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->dev, "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->dev, "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->dev,
 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->dev, "IBF timeout\n");
 213                 return -EIO;
 214         }
 215         outb(NSC_COMMAND_EOC, chip->vendor.base + NSC_COMMAND);
 216
 217         return count;
 218 }
 219
 220 static void tpm_nsc_cancel(struct tpm_chip *chip)
 221 {
 222         outb(NSC_COMMAND_CANCEL, chip->vendor.base + NSC_COMMAND);
 223 }
 224
 225 static u8 tpm_nsc_status(struct tpm_chip *chip)
 226 {
 227         return inb(chip->vendor.base + NSC_STATUS);
 228 }
 229
 230 static bool tpm_nsc_req_canceled(struct tpm_chip *chip, u8 status)
 231 {
 232         return (status == NSC_STATUS_RDY);
 233 }
 234
 235 static const struct file_operations nsc_ops = {
 236         .owner = THIS_MODULE,
 237         .llseek = no_llseek,
 238         .open = tpm_open,
 239         .read = tpm_read,
 240         .write = tpm_write,
 241         .release = tpm_release,
 242 };
 243
 244 static DEVICE_ATTR(pubek, S_IRUGO, tpm_show_pubek, NULL);
 245 static DEVICE_ATTR(pcrs, S_IRUGO, tpm_show_pcrs, NULL);
 246 static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps, NULL);
 247 static DEVICE_ATTR(cancel, S_IWUSR|S_IWGRP, NULL, tpm_store_cancel);
 248
 249 static struct attribute * nsc_attrs[] = {
 250         &dev_attr_pubek.attr,
 251         &dev_attr_pcrs.attr,
 252         &dev_attr_caps.attr,
 253         &dev_attr_cancel.attr,
 254         NULL,
 255 };
 256
 257 static struct attribute_group nsc_attr_grp = { .attrs = nsc_attrs };
 258
 259 static const struct tpm_vendor_specific tpm_nsc = {
 260         .recv = tpm_nsc_recv,
 261         .send = tpm_nsc_send,
 262         .cancel = tpm_nsc_cancel,
 263         .status = tpm_nsc_status,
 264         .req_complete_mask = NSC_STATUS_OBF,
 265         .req_complete_val = NSC_STATUS_OBF,
 266         .req_canceled = tpm_nsc_req_canceled,
 267         .attr_group = &nsc_attr_grp,
 268         .miscdev = { .fops = &nsc_ops, },
 269 };
 270
 271 static struct platform_device *pdev = NULL;
 272
 273 static void tpm_nsc_remove(struct device *dev)
 274 {
 275         struct tpm_chip *chip = dev_get_drvdata(dev);
 276         if ( chip ) {
 277                 release_region(chip->vendor.base, 2);
 278                 tpm_remove_hardware(chip->dev);
 279         }
 280 }
 281
 282 static SIMPLE_DEV_PM_OPS(tpm_nsc_pm, tpm_pm_suspend, tpm_pm_resume);
 283
 284 static struct platform_driver nsc_drv = {
 285         .driver          = {
 286                 .name    = "tpm_nsc",
 287                 .owner   = THIS_MODULE,
 288                 .pm      = &tpm_nsc_pm,
 289         },
 290 };
 291
 292 static int __init init_nsc(void)
 293 {
 294         int rc = 0;
 295         int lo, hi, err;
 296         int nscAddrBase = TPM_ADDR;
 297         struct tpm_chip *chip;
 298         unsigned long base;
 299
 300         /* verify that it is a National part (SID) */
 301         if (tpm_read_index(TPM_ADDR, NSC_SID_INDEX) != 0xEF) {
 302                 nscAddrBase = (tpm_read_index(TPM_SUPERIO_ADDR, 0x2C)<<8)|
 303                         (tpm_read_index(TPM_SUPERIO_ADDR, 0x2B)&0xFE);
 304                 if (tpm_read_index(nscAddrBase, NSC_SID_INDEX) != 0xF6)
 305                         return -ENODEV;
 306         }
 307
 308         err = platform_driver_register(&nsc_drv);
 309         if (err)
 310                 return err;
 311
 312         hi = tpm_read_index(nscAddrBase, TPM_NSC_BASE0_HI);
 313         lo = tpm_read_index(nscAddrBase, TPM_NSC_BASE0_LO);
 314         base = (hi<<8) | lo;
 315
 316         /* enable the DPM module */
 317         tpm_write_index(nscAddrBase, NSC_LDC_INDEX, 0x01);
 318
 319         pdev = platform_device_alloc("tpm_nscl0", -1);
 320         if (!pdev) {
 321                 rc = -ENOMEM;
 322                 goto err_unreg_drv;
 323         }
 324
 325         pdev->num_resources = 0;
 326         pdev->dev.driver = &nsc_drv.driver;
 327         pdev->dev.release = tpm_nsc_remove;
 328
 329         if ((rc = platform_device_add(pdev)) < 0)
 330                 goto err_put_dev;
 331
 332         if (request_region(base, 2, "tpm_nsc0") == NULL ) {
 333                 rc = -EBUSY;
 334                 goto err_del_dev;
 335         }
 336
 337         if (!(chip = tpm_register_hardware(&pdev->dev, &tpm_nsc))) {
 338                 rc = -ENODEV;
 339                 goto err_rel_reg;
 340         }
 341
 342         dev_dbg(&pdev->dev, "NSC TPM detected\n");
 343         dev_dbg(&pdev->dev,
 344                 "NSC LDN 0x%x, SID 0x%x, SRID 0x%x\n",
 345                 tpm_read_index(nscAddrBase,0x07), tpm_read_index(nscAddrBase,0x20),
 346                 tpm_read_index(nscAddrBase,0x27));
 347         dev_dbg(&pdev->dev,
 348                 "NSC SIOCF1 0x%x SIOCF5 0x%x SIOCF6 0x%x SIOCF8 0x%x\n",
 349                 tpm_read_index(nscAddrBase,0x21), tpm_read_index(nscAddrBase,0x25),
 350                 tpm_read_index(nscAddrBase,0x26), tpm_read_index(nscAddrBase,0x28));
 351         dev_dbg(&pdev->dev, "NSC IO Base0 0x%x\n",
 352                 (tpm_read_index(nscAddrBase,0x60) << 8) | tpm_read_index(nscAddrBase,0x61));
 353         dev_dbg(&pdev->dev, "NSC IO Base1 0x%x\n",
 354                 (tpm_read_index(nscAddrBase,0x62) << 8) | tpm_read_index(nscAddrBase,0x63));
 355         dev_dbg(&pdev->dev, "NSC Interrupt number and wakeup 0x%x\n",
 356                 tpm_read_index(nscAddrBase,0x70));
 357         dev_dbg(&pdev->dev, "NSC IRQ type select 0x%x\n",
 358                 tpm_read_index(nscAddrBase,0x71));
 359         dev_dbg(&pdev->dev,
 360                 "NSC DMA channel select0 0x%x, select1 0x%x\n",
 361                 tpm_read_index(nscAddrBase,0x74), tpm_read_index(nscAddrBase,0x75));
 362         dev_dbg(&pdev->dev,
 363                 "NSC Config "
 364                 "0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x\n",
 365                 tpm_read_index(nscAddrBase,0xF0), tpm_read_index(nscAddrBase,0xF1),
 366                 tpm_read_index(nscAddrBase,0xF2), tpm_read_index(nscAddrBase,0xF3),
 367                 tpm_read_index(nscAddrBase,0xF4), tpm_read_index(nscAddrBase,0xF5),
 368                 tpm_read_index(nscAddrBase,0xF6), tpm_read_index(nscAddrBase,0xF7),
 369                 tpm_read_index(nscAddrBase,0xF8), tpm_read_index(nscAddrBase,0xF9));
 370
 371         dev_info(&pdev->dev,
 372                  "NSC TPM revision %d\n",
 373                  tpm_read_index(nscAddrBase, 0x27) & 0x1F);
 374
 375         chip->vendor.base = base;
 376
 377         return 0;
 378
 379 err_rel_reg:
 380         release_region(base, 2);
 381 err_del_dev:
 382         platform_device_del(pdev);
 383 err_put_dev:
 384         platform_device_put(pdev);
 385 err_unreg_drv:
 386         platform_driver_unregister(&nsc_drv);
 387         return rc;
 388 }
 389
 390 static void __exit cleanup_nsc(void)
 391 {
 392         if (pdev) {
 393                 tpm_nsc_remove(&pdev->dev);
 394                 platform_device_unregister(pdev);
 395         }
 396
 397         platform_driver_unregister(&nsc_drv);
 398 }
 399
 400 module_init(init_nsc);
 401 module_exit(cleanup_nsc);
 402
 403 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
 404 MODULE_DESCRIPTION("TPM Driver");
 405 MODULE_VERSION("2.0");
 406 MODULE_LICENSE("GPL");