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 "tpm.h"
  24
  25 /* National definitions */
  26 enum tpm_nsc_addr{
  27         TPM_NSC_IRQ = 0x07,
  28         TPM_NSC_BASE0_HI = 0x60,
  29         TPM_NSC_BASE0_LO = 0x61,
  30         TPM_NSC_BASE1_HI = 0x62,
  31         TPM_NSC_BASE1_LO = 0x63
  32 };
  33
  34 enum tpm_nsc_index {
  35         NSC_LDN_INDEX = 0x07,
  36         NSC_SID_INDEX = 0x20,
  37         NSC_LDC_INDEX = 0x30,
  38         NSC_DIO_INDEX = 0x60,
  39         NSC_CIO_INDEX = 0x62,
  40         NSC_IRQ_INDEX = 0x70,
  41         NSC_ITS_INDEX = 0x71
  42 };
  43
  44 enum tpm_nsc_status_loc {
  45         NSC_STATUS = 0x01,
  46         NSC_COMMAND = 0x01,
  47         NSC_DATA = 0x00
  48 };
  49
  50 /* status bits */
  51 enum tpm_nsc_status {
  52         NSC_STATUS_OBF = 0x01,  /* output buffer full */
  53         NSC_STATUS_IBF = 0x02,  /* input buffer full */
  54         NSC_STATUS_F0 = 0x04,   /* F0 */
  55         NSC_STATUS_A2 = 0x08,   /* A2 */
  56         NSC_STATUS_RDY = 0x10,  /* ready to receive command */
  57         NSC_STATUS_IBR = 0x20   /* ready to receive data */
  58 };
  59
  60 /* command bits */
  61 enum tpm_nsc_cmd_mode {
  62         NSC_COMMAND_NORMAL = 0x01,      /* normal mode */
  63         NSC_COMMAND_EOC = 0x03,
  64         NSC_COMMAND_CANCEL = 0x22
  65 };
  66 /*
  67  * Wait for a certain status to appear
  68  */
  69 static int wait_for_stat(struct tpm_chip *chip, u8 mask, u8 val, u8 * data)
  70 {
  71         unsigned long stop;
  72
  73         /* status immediately available check */
  74         *data = inb(chip->vendor.base + NSC_STATUS);
  75         if ((*data & mask) == val)
  76                 return 0;
  77
  78         /* wait for status */
  79         stop = jiffies + 10 * HZ;
  80         do {
  81                 msleep(TPM_TIMEOUT);
  82                 *data = inb(chip->vendor.base + 1);
  83                 if ((*data & mask) == val)
  84                         return 0;
  85         }
  86         while (time_before(jiffies, stop));
  87
  88         return -EBUSY;
  89 }
  90
  91 static int nsc_wait_for_ready(struct tpm_chip *chip)
  92 {
  93         int status;
  94         unsigned long stop;
  95
  96         /* status immediately available check */
  97         status = inb(chip->vendor.base + NSC_STATUS);
  98         if (status & NSC_STATUS_OBF)
  99                 status = inb(chip->vendor.base + NSC_DATA);
 100         if (status & NSC_STATUS_RDY)
 101                 return 0;
 102
 103         /* wait for status */
 104         stop = jiffies + 100;
 105         do {
 106                 msleep(TPM_TIMEOUT);
 107                 status = inb(chip->vendor.base + NSC_STATUS);
 108                 if (status & NSC_STATUS_OBF)
 109                         status = inb(chip->vendor.base + NSC_DATA);
 110                 if (status & NSC_STATUS_RDY)
 111                         return 0;
 112         }
 113         while (time_before(jiffies, stop));
 114
 115         dev_info(chip->dev, "wait for ready failed\n");
 116         return -EBUSY;
 117 }
 118
 119
 120 static int tpm_nsc_recv(struct tpm_chip *chip, u8 * buf, size_t count)
 121 {
 122         u8 *buffer = buf;
 123         u8 data, *p;
 124         u32 size;
 125         __be32 *native_size;
 126
 127         if (count < 6)
 128                 return -EIO;
 129
 130         if (wait_for_stat(chip, NSC_STATUS_F0, NSC_STATUS_F0, &data) < 0) {
 131                 dev_err(chip->dev, "F0 timeout\n");
 132                 return -EIO;
 133         }
 134         if ((data =
 135              inb(chip->vendor.base + NSC_DATA)) != NSC_COMMAND_NORMAL) {
 136                 dev_err(chip->dev, "not in normal mode (0x%x)\n",
 137                         data);
 138                 return -EIO;
 139         }
 140
 141         /* read the whole packet */
 142         for (p = buffer; p < &buffer[count]; p++) {
 143                 if (wait_for_stat
 144                     (chip, NSC_STATUS_OBF, NSC_STATUS_OBF, &data) < 0) {
 145                         dev_err(chip->dev,
 146                                 "OBF timeout (while reading data)\n");
 147                         return -EIO;
 148                 }
 149                 if (data & NSC_STATUS_F0)
 150                         break;
 151                 *p = inb(chip->vendor.base + NSC_DATA);
 152         }
 153
 154         if ((data & NSC_STATUS_F0) == 0 &&
 155         (wait_for_stat(chip, NSC_STATUS_F0, NSC_STATUS_F0, &data) < 0)) {
 156                 dev_err(chip->dev, "F0 not set\n");
 157                 return -EIO;
 158         }
 159         if ((data = inb(chip->vendor.base + NSC_DATA)) != NSC_COMMAND_EOC) {
 160                 dev_err(chip->dev,
 161                         "expected end of command(0x%x)\n", data);
 162                 return -EIO;
 163         }
 164
 165         native_size = (__force __be32 *) (buf + 2);
 166         size = be32_to_cpu(*native_size);
 167
 168         if (count < size)
 169                 return -EIO;
 170
 171         return size;
 172 }
 173
 174 static int tpm_nsc_send(struct tpm_chip *chip, u8 * buf, size_t count)
 175 {
 176         u8 data;
 177         int i;
 178
 179         /*
 180          * If we hit the chip with back to back commands it locks up
 181          * and never set IBF. Hitting it with this "hammer" seems to
 182          * fix it. Not sure why this is needed, we followed the flow
 183          * chart in the manual to the letter.
 184          */
 185         outb(NSC_COMMAND_CANCEL, chip->vendor.base + NSC_COMMAND);
 186
 187         if (nsc_wait_for_ready(chip) != 0)
 188                 return -EIO;
 189
 190         if (wait_for_stat(chip, NSC_STATUS_IBF, 0, &data) < 0) {
 191                 dev_err(chip->dev, "IBF timeout\n");
 192                 return -EIO;
 193         }
 194
 195         outb(NSC_COMMAND_NORMAL, chip->vendor.base + NSC_COMMAND);
 196         if (wait_for_stat(chip, NSC_STATUS_IBR, NSC_STATUS_IBR, &data) < 0) {
 197                 dev_err(chip->dev, "IBR timeout\n");
 198                 return -EIO;
 199         }
 200
 201         for (i = 0; i < count; i++) {
 202                 if (wait_for_stat(chip, NSC_STATUS_IBF, 0, &data) < 0) {
 203                         dev_err(chip->dev,
 204                                 "IBF timeout (while writing data)\n");
 205                         return -EIO;
 206                 }
 207                 outb(buf[i], chip->vendor.base + NSC_DATA);
 208         }
 209
 210         if (wait_for_stat(chip, NSC_STATUS_IBF, 0, &data) < 0) {
 211                 dev_err(chip->dev, "IBF timeout\n");
 212                 return -EIO;
 213         }
 214         outb(NSC_COMMAND_EOC, chip->vendor.base + NSC_COMMAND);
 215
 216         return count;
 217 }
 218
 219 static void tpm_nsc_cancel(struct tpm_chip *chip)
 220 {
 221         outb(NSC_COMMAND_CANCEL, chip->vendor.base + NSC_COMMAND);
 222 }
 223
 224 static u8 tpm_nsc_status(struct tpm_chip *chip)
 225 {
 226         return inb(chip->vendor.base + NSC_STATUS);
 227 }
 228
 229 static struct file_operations nsc_ops = {
 230         .owner = THIS_MODULE,
 231         .llseek = no_llseek,
 232         .open = tpm_open,
 233         .read = tpm_read,
 234         .write = tpm_write,
 235         .release = tpm_release,
 236 };
 237
 238 static DEVICE_ATTR(pubek, S_IRUGO, tpm_show_pubek, NULL);
 239 static DEVICE_ATTR(pcrs, S_IRUGO, tpm_show_pcrs, NULL);
 240 static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps, NULL);
 241 static DEVICE_ATTR(cancel, S_IWUSR|S_IWGRP, NULL, tpm_store_cancel);
 242
 243 static struct attribute * nsc_attrs[] = {
 244         &dev_attr_pubek.attr,
 245         &dev_attr_pcrs.attr,
 246         &dev_attr_caps.attr,
 247         &dev_attr_cancel.attr,
 248         NULL,
 249 };
 250
 251 static struct attribute_group nsc_attr_grp = { .attrs = nsc_attrs };
 252
 253 static const struct tpm_vendor_specific tpm_nsc = {
 254         .recv = tpm_nsc_recv,
 255         .send = tpm_nsc_send,
 256         .cancel = tpm_nsc_cancel,
 257         .status = tpm_nsc_status,
 258         .req_complete_mask = NSC_STATUS_OBF,
 259         .req_complete_val = NSC_STATUS_OBF,
 260         .req_canceled = NSC_STATUS_RDY,
 261         .attr_group = &nsc_attr_grp,
 262         .miscdev = { .fops = &nsc_ops, },
 263 };
 264
 265 static struct platform_device *pdev = NULL;
 266
 267 static void __devexit tpm_nsc_remove(struct device *dev)
 268 {
 269         struct tpm_chip *chip = dev_get_drvdata(dev);
 270         if ( chip ) {
 271                 release_region(chip->vendor.base, 2);
 272                 tpm_remove_hardware(chip->dev);
 273         }
 274 }
 275
 276 static struct device_driver nsc_drv = {
 277         .name = "tpm_nsc",
 278         .bus = &platform_bus_type,
 279         .owner = THIS_MODULE,
 280         .suspend = tpm_pm_suspend,
 281         .resume = tpm_pm_resume,
 282 };
 283
 284 static int __init init_nsc(void)
 285 {
 286         int rc = 0;
 287         int lo, hi;
 288         int nscAddrBase = TPM_ADDR;
 289         struct tpm_chip *chip;
 290         unsigned long base;
 291
 292         /* verify that it is a National part (SID) */
 293         if (tpm_read_index(TPM_ADDR, NSC_SID_INDEX) != 0xEF) {
 294                 nscAddrBase = (tpm_read_index(TPM_SUPERIO_ADDR, 0x2C)<<8)|
 295                         (tpm_read_index(TPM_SUPERIO_ADDR, 0x2B)&0xFE);
 296                 if (tpm_read_index(nscAddrBase, NSC_SID_INDEX) != 0xF6)
 297                         return -ENODEV;
 298         }
 299
 300         driver_register(&nsc_drv);
 301
 302         hi = tpm_read_index(nscAddrBase, TPM_NSC_BASE0_HI);
 303         lo = tpm_read_index(nscAddrBase, TPM_NSC_BASE0_LO);
 304         base = (hi<<8) | lo;
 305
 306         /* enable the DPM module */
 307         tpm_write_index(nscAddrBase, NSC_LDC_INDEX, 0x01);
 308
 309         pdev = kzalloc(sizeof(struct platform_device), GFP_KERNEL);
 310         if (!pdev) {
 311                 rc = -ENOMEM;
 312                 goto err_unreg_drv;
 313         }
 314
 315         pdev->name = "tpm_nscl0";
 316         pdev->id = -1;
 317         pdev->num_resources = 0;
 318         pdev->dev.release = tpm_nsc_remove;
 319         pdev->dev.driver = &nsc_drv;
 320
 321         if ((rc = platform_device_register(pdev)) < 0)
 322                 goto err_free_dev;
 323
 324         if (request_region(base, 2, "tpm_nsc0") == NULL ) {
 325                 rc = -EBUSY;
 326                 goto err_unreg_dev;
 327         }
 328
 329         if (!(chip = tpm_register_hardware(&pdev->dev, &tpm_nsc))) {
 330                 rc = -ENODEV;
 331                 goto err_rel_reg;
 332         }
 333
 334         dev_dbg(&pdev->dev, "NSC TPM detected\n");
 335         dev_dbg(&pdev->dev,
 336                 "NSC LDN 0x%x, SID 0x%x, SRID 0x%x\n",
 337                 tpm_read_index(nscAddrBase,0x07), tpm_read_index(nscAddrBase,0x20),
 338                 tpm_read_index(nscAddrBase,0x27));
 339         dev_dbg(&pdev->dev,
 340                 "NSC SIOCF1 0x%x SIOCF5 0x%x SIOCF6 0x%x SIOCF8 0x%x\n",
 341                 tpm_read_index(nscAddrBase,0x21), tpm_read_index(nscAddrBase,0x25),
 342                 tpm_read_index(nscAddrBase,0x26), tpm_read_index(nscAddrBase,0x28));
 343         dev_dbg(&pdev->dev, "NSC IO Base0 0x%x\n",
 344                 (tpm_read_index(nscAddrBase,0x60) << 8) | tpm_read_index(nscAddrBase,0x61));
 345         dev_dbg(&pdev->dev, "NSC IO Base1 0x%x\n",
 346                 (tpm_read_index(nscAddrBase,0x62) << 8) | tpm_read_index(nscAddrBase,0x63));
 347         dev_dbg(&pdev->dev, "NSC Interrupt number and wakeup 0x%x\n",
 348                 tpm_read_index(nscAddrBase,0x70));
 349         dev_dbg(&pdev->dev, "NSC IRQ type select 0x%x\n",
 350                 tpm_read_index(nscAddrBase,0x71));
 351         dev_dbg(&pdev->dev,
 352                 "NSC DMA channel select0 0x%x, select1 0x%x\n",
 353                 tpm_read_index(nscAddrBase,0x74), tpm_read_index(nscAddrBase,0x75));
 354         dev_dbg(&pdev->dev,
 355                 "NSC Config "
 356                 "0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x\n",
 357                 tpm_read_index(nscAddrBase,0xF0), tpm_read_index(nscAddrBase,0xF1),
 358                 tpm_read_index(nscAddrBase,0xF2), tpm_read_index(nscAddrBase,0xF3),
 359                 tpm_read_index(nscAddrBase,0xF4), tpm_read_index(nscAddrBase,0xF5),
 360                 tpm_read_index(nscAddrBase,0xF6), tpm_read_index(nscAddrBase,0xF7),
 361                 tpm_read_index(nscAddrBase,0xF8), tpm_read_index(nscAddrBase,0xF9));
 362
 363         dev_info(&pdev->dev,
 364                  "NSC TPM revision %d\n",
 365                  tpm_read_index(nscAddrBase, 0x27) & 0x1F);
 366
 367         chip->vendor.base = base;
 368
 369         return 0;
 370
 371 err_rel_reg:
 372         release_region(base, 2);
 373 err_unreg_dev:
 374         platform_device_unregister(pdev);
 375 err_free_dev:
 376         kfree(pdev);
 377 err_unreg_drv:
 378         driver_unregister(&nsc_drv);
 379         return rc;
 380 }
 381
 382 static void __exit cleanup_nsc(void)
 383 {
 384         if (pdev) {
 385                 tpm_nsc_remove(&pdev->dev);
 386                 platform_device_unregister(pdev);
 387                 kfree(pdev);
 388                 pdev = NULL;
 389         }
 390
 391         driver_unregister(&nsc_drv);
 392 }
 393
 394 module_init(init_nsc);
 395 module_exit(cleanup_nsc);
 396
 397 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
 398 MODULE_DESCRIPTION("TPM Driver");
 399 MODULE_VERSION("2.0");
 400 MODULE_LICENSE("GPL");