drivers/char/tpm/tpm_nsc.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2004 IBM Corporation
   4  *
   5  * Authors:
   6  * Leendert van Doorn <leendert@watson.ibm.com>
   7  * Dave Safford <safford@watson.ibm.com>
   8  * Reiner Sailer <sailer@watson.ibm.com>
   9  * Kylene Hall <kjhall@us.ibm.com>
  10  *
  11  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
  12  *
  13  * Device driver for TCG/TCPA TPM (trusted platform module).
  14  * Specifications at www.trustedcomputinggroup.org
  15  */
  16
  17 #include <linux/platform_device.h>
  18 #include <linux/slab.h>
  19 #include "tpm.h"
  20
  21 /* National definitions */
  22 enum tpm_nsc_addr{
  23         TPM_NSC_IRQ = 0x07,
  24         TPM_NSC_BASE0_HI = 0x60,
  25         TPM_NSC_BASE0_LO = 0x61,
  26         TPM_NSC_BASE1_HI = 0x62,
  27         TPM_NSC_BASE1_LO = 0x63
  28 };
  29
  30 enum tpm_nsc_index {
  31         NSC_LDN_INDEX = 0x07,
  32         NSC_SID_INDEX = 0x20,
  33         NSC_LDC_INDEX = 0x30,
  34         NSC_DIO_INDEX = 0x60,
  35         NSC_CIO_INDEX = 0x62,
  36         NSC_IRQ_INDEX = 0x70,
  37         NSC_ITS_INDEX = 0x71
  38 };
  39
  40 enum tpm_nsc_status_loc {
  41         NSC_STATUS = 0x01,
  42         NSC_COMMAND = 0x01,
  43         NSC_DATA = 0x00
  44 };
  45
  46 /* status bits */
  47 enum tpm_nsc_status {
  48         NSC_STATUS_OBF = 0x01,  /* output buffer full */
  49         NSC_STATUS_IBF = 0x02,  /* input buffer full */
  50         NSC_STATUS_F0 = 0x04,   /* F0 */
  51         NSC_STATUS_A2 = 0x08,   /* A2 */
  52         NSC_STATUS_RDY = 0x10,  /* ready to receive command */
  53         NSC_STATUS_IBR = 0x20   /* ready to receive data */
  54 };
  55
  56 /* command bits */
  57 enum tpm_nsc_cmd_mode {
  58         NSC_COMMAND_NORMAL = 0x01,      /* normal mode */
  59         NSC_COMMAND_EOC = 0x03,
  60         NSC_COMMAND_CANCEL = 0x22
  61 };
  62
  63 struct tpm_nsc_priv {
  64         unsigned long base;
  65 };
  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         struct tpm_nsc_priv *priv = dev_get_drvdata(&chip->dev);
  73         unsigned long stop;
  74
  75         /* status immediately available check */
  76         *data = inb(priv->base + NSC_STATUS);
  77         if ((*data & mask) == val)
  78                 return 0;
  79
  80         /* wait for status */
  81         stop = jiffies + 10 * HZ;
  82         do {
  83                 msleep(TPM_TIMEOUT);
  84                 *data = inb(priv->base + 1);
  85                 if ((*data & mask) == val)
  86                         return 0;
  87         }
  88         while (time_before(jiffies, stop));
  89
  90         return -EBUSY;
  91 }
  92
  93 static int nsc_wait_for_ready(struct tpm_chip *chip)
  94 {
  95         struct tpm_nsc_priv *priv = dev_get_drvdata(&chip->dev);
  96         int status;
  97         unsigned long stop;
  98
  99         /* status immediately available check */
 100         status = inb(priv->base + NSC_STATUS);
 101         if (status & NSC_STATUS_OBF)
 102                 status = inb(priv->base + NSC_DATA);
 103         if (status & NSC_STATUS_RDY)
 104                 return 0;
 105
 106         /* wait for status */
 107         stop = jiffies + 100;
 108         do {
 109                 msleep(TPM_TIMEOUT);
 110                 status = inb(priv->base + NSC_STATUS);
 111                 if (status & NSC_STATUS_OBF)
 112                         status = inb(priv->base + NSC_DATA);
 113                 if (status & NSC_STATUS_RDY)
 114                         return 0;
 115         }
 116         while (time_before(jiffies, stop));
 117
 118         dev_info(&chip->dev, "wait for ready failed\n");
 119         return -EBUSY;
 120 }
 121
 122
 123 static int tpm_nsc_recv(struct tpm_chip *chip, u8 * buf, size_t count)
 124 {
 125         struct tpm_nsc_priv *priv = dev_get_drvdata(&chip->dev);
 126         u8 *buffer = buf;
 127         u8 data, *p;
 128         u32 size;
 129         __be32 *native_size;
 130
 131         if (count < 6)
 132                 return -EIO;
 133
 134         if (wait_for_stat(chip, NSC_STATUS_F0, NSC_STATUS_F0, &data) < 0) {
 135                 dev_err(&chip->dev, "F0 timeout\n");
 136                 return -EIO;
 137         }
 138
 139         data = inb(priv->base + NSC_DATA);
 140         if (data != NSC_COMMAND_NORMAL) {
 141                 dev_err(&chip->dev, "not in normal mode (0x%x)\n",
 142                         data);
 143                 return -EIO;
 144         }
 145
 146         /* read the whole packet */
 147         for (p = buffer; p < &buffer[count]; p++) {
 148                 if (wait_for_stat
 149                     (chip, NSC_STATUS_OBF, NSC_STATUS_OBF, &data) < 0) {
 150                         dev_err(&chip->dev,
 151                                 "OBF timeout (while reading data)\n");
 152                         return -EIO;
 153                 }
 154                 if (data & NSC_STATUS_F0)
 155                         break;
 156                 *p = inb(priv->base + NSC_DATA);
 157         }
 158
 159         if ((data & NSC_STATUS_F0) == 0 &&
 160         (wait_for_stat(chip, NSC_STATUS_F0, NSC_STATUS_F0, &data) < 0)) {
 161                 dev_err(&chip->dev, "F0 not set\n");
 162                 return -EIO;
 163         }
 164
 165         data = inb(priv->base + NSC_DATA);
 166         if (data != NSC_COMMAND_EOC) {
 167                 dev_err(&chip->dev,
 168                         "expected end of command(0x%x)\n", data);
 169                 return -EIO;
 170         }
 171
 172         native_size = (__force __be32 *) (buf + 2);
 173         size = be32_to_cpu(*native_size);
 174
 175         if (count < size)
 176                 return -EIO;
 177
 178         return size;
 179 }
 180
 181 static int tpm_nsc_send(struct tpm_chip *chip, u8 * buf, size_t count)
 182 {
 183         struct tpm_nsc_priv *priv = dev_get_drvdata(&chip->dev);
 184         u8 data;
 185         int i;
 186
 187         /*
 188          * If we hit the chip with back to back commands it locks up
 189          * and never set IBF. Hitting it with this "hammer" seems to
 190          * fix it. Not sure why this is needed, we followed the flow
 191          * chart in the manual to the letter.
 192          */
 193         outb(NSC_COMMAND_CANCEL, priv->base + NSC_COMMAND);
 194
 195         if (nsc_wait_for_ready(chip) != 0)
 196                 return -EIO;
 197
 198         if (wait_for_stat(chip, NSC_STATUS_IBF, 0, &data) < 0) {
 199                 dev_err(&chip->dev, "IBF timeout\n");
 200                 return -EIO;
 201         }
 202
 203         outb(NSC_COMMAND_NORMAL, priv->base + NSC_COMMAND);
 204         if (wait_for_stat(chip, NSC_STATUS_IBR, NSC_STATUS_IBR, &data) < 0) {
 205                 dev_err(&chip->dev, "IBR timeout\n");
 206                 return -EIO;
 207         }
 208
 209         for (i = 0; i < count; i++) {
 210                 if (wait_for_stat(chip, NSC_STATUS_IBF, 0, &data) < 0) {
 211                         dev_err(&chip->dev,
 212                                 "IBF timeout (while writing data)\n");
 213                         return -EIO;
 214                 }
 215                 outb(buf[i], priv->base + NSC_DATA);
 216         }
 217
 218         if (wait_for_stat(chip, NSC_STATUS_IBF, 0, &data) < 0) {
 219                 dev_err(&chip->dev, "IBF timeout\n");
 220                 return -EIO;
 221         }
 222         outb(NSC_COMMAND_EOC, priv->base + NSC_COMMAND);
 223
 224         return 0;
 225 }
 226
 227 static void tpm_nsc_cancel(struct tpm_chip *chip)
 228 {
 229         struct tpm_nsc_priv *priv = dev_get_drvdata(&chip->dev);
 230
 231         outb(NSC_COMMAND_CANCEL, priv->base + NSC_COMMAND);
 232 }
 233
 234 static u8 tpm_nsc_status(struct tpm_chip *chip)
 235 {
 236         struct tpm_nsc_priv *priv = dev_get_drvdata(&chip->dev);
 237
 238         return inb(priv->base + NSC_STATUS);
 239 }
 240
 241 static bool tpm_nsc_req_canceled(struct tpm_chip *chip, u8 status)
 242 {
 243         return (status == NSC_STATUS_RDY);
 244 }
 245
 246 static const struct tpm_class_ops tpm_nsc = {
 247         .recv = tpm_nsc_recv,
 248         .send = tpm_nsc_send,
 249         .cancel = tpm_nsc_cancel,
 250         .status = tpm_nsc_status,
 251         .req_complete_mask = NSC_STATUS_OBF,
 252         .req_complete_val = NSC_STATUS_OBF,
 253         .req_canceled = tpm_nsc_req_canceled,
 254 };
 255
 256 static struct platform_device *pdev = NULL;
 257
 258 static void tpm_nsc_remove(struct device *dev)
 259 {
 260         struct tpm_chip *chip = dev_get_drvdata(dev);
 261         struct tpm_nsc_priv *priv = dev_get_drvdata(&chip->dev);
 262
 263         tpm_chip_unregister(chip);
 264         release_region(priv->base, 2);
 265 }
 266
 267 static SIMPLE_DEV_PM_OPS(tpm_nsc_pm, tpm_pm_suspend, tpm_pm_resume);
 268
 269 static struct platform_driver nsc_drv = {
 270         .driver          = {
 271                 .name    = "tpm_nsc",
 272                 .pm      = &tpm_nsc_pm,
 273         },
 274 };
 275
 276 static inline int tpm_read_index(int base, int index)
 277 {
 278         outb(index, base);
 279         return inb(base+1) & 0xFF;
 280 }
 281
 282 static inline void tpm_write_index(int base, int index, int value)
 283 {
 284         outb(index, base);
 285         outb(value & 0xFF, base+1);
 286 }
 287
 288 static int __init init_nsc(void)
 289 {
 290         int rc = 0;
 291         int lo, hi, err;
 292         int nscAddrBase = TPM_ADDR;
 293         struct tpm_chip *chip;
 294         unsigned long base;
 295         struct tpm_nsc_priv *priv;
 296
 297         /* verify that it is a National part (SID) */
 298         if (tpm_read_index(TPM_ADDR, NSC_SID_INDEX) != 0xEF) {
 299                 nscAddrBase = (tpm_read_index(TPM_SUPERIO_ADDR, 0x2C)<<8)|
 300                         (tpm_read_index(TPM_SUPERIO_ADDR, 0x2B)&0xFE);
 301                 if (tpm_read_index(nscAddrBase, NSC_SID_INDEX) != 0xF6)
 302                         return -ENODEV;
 303         }
 304
 305         err = platform_driver_register(&nsc_drv);
 306         if (err)
 307                 return err;
 308
 309         hi = tpm_read_index(nscAddrBase, TPM_NSC_BASE0_HI);
 310         lo = tpm_read_index(nscAddrBase, TPM_NSC_BASE0_LO);
 311         base = (hi<<8) | lo;
 312
 313         /* enable the DPM module */
 314         tpm_write_index(nscAddrBase, NSC_LDC_INDEX, 0x01);
 315
 316         pdev = platform_device_alloc("tpm_nscl0", -1);
 317         if (!pdev) {
 318                 rc = -ENOMEM;
 319                 goto err_unreg_drv;
 320         }
 321
 322         pdev->num_resources = 0;
 323         pdev->dev.driver = &nsc_drv.driver;
 324         pdev->dev.release = tpm_nsc_remove;
 325
 326         if ((rc = platform_device_add(pdev)) < 0)
 327                 goto err_put_dev;
 328
 329         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 330         if (!priv) {
 331                 rc = -ENOMEM;
 332                 goto err_del_dev;
 333         }
 334
 335         priv->base = base;
 336
 337         if (request_region(base, 2, "tpm_nsc0") == NULL ) {
 338                 rc = -EBUSY;
 339                 goto err_del_dev;
 340         }
 341
 342         chip = tpmm_chip_alloc(&pdev->dev, &tpm_nsc);
 343         if (IS_ERR(chip)) {
 344                 rc = -ENODEV;
 345                 goto err_rel_reg;
 346         }
 347
 348         dev_set_drvdata(&chip->dev, priv);
 349
 350         rc = tpm_chip_register(chip);
 351         if (rc)
 352                 goto err_rel_reg;
 353
 354         dev_dbg(&pdev->dev, "NSC TPM detected\n");
 355         dev_dbg(&pdev->dev,
 356                 "NSC LDN 0x%x, SID 0x%x, SRID 0x%x\n",
 357                 tpm_read_index(nscAddrBase,0x07), tpm_read_index(nscAddrBase,0x20),
 358                 tpm_read_index(nscAddrBase,0x27));
 359         dev_dbg(&pdev->dev,
 360                 "NSC SIOCF1 0x%x SIOCF5 0x%x SIOCF6 0x%x SIOCF8 0x%x\n",
 361                 tpm_read_index(nscAddrBase,0x21), tpm_read_index(nscAddrBase,0x25),
 362                 tpm_read_index(nscAddrBase,0x26), tpm_read_index(nscAddrBase,0x28));
 363         dev_dbg(&pdev->dev, "NSC IO Base0 0x%x\n",
 364                 (tpm_read_index(nscAddrBase,0x60) << 8) | tpm_read_index(nscAddrBase,0x61));
 365         dev_dbg(&pdev->dev, "NSC IO Base1 0x%x\n",
 366                 (tpm_read_index(nscAddrBase,0x62) << 8) | tpm_read_index(nscAddrBase,0x63));
 367         dev_dbg(&pdev->dev, "NSC Interrupt number and wakeup 0x%x\n",
 368                 tpm_read_index(nscAddrBase,0x70));
 369         dev_dbg(&pdev->dev, "NSC IRQ type select 0x%x\n",
 370                 tpm_read_index(nscAddrBase,0x71));
 371         dev_dbg(&pdev->dev,
 372                 "NSC DMA channel select0 0x%x, select1 0x%x\n",
 373                 tpm_read_index(nscAddrBase,0x74), tpm_read_index(nscAddrBase,0x75));
 374         dev_dbg(&pdev->dev,
 375                 "NSC Config "
 376                 "0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x\n",
 377                 tpm_read_index(nscAddrBase,0xF0), tpm_read_index(nscAddrBase,0xF1),
 378                 tpm_read_index(nscAddrBase,0xF2), tpm_read_index(nscAddrBase,0xF3),
 379                 tpm_read_index(nscAddrBase,0xF4), tpm_read_index(nscAddrBase,0xF5),
 380                 tpm_read_index(nscAddrBase,0xF6), tpm_read_index(nscAddrBase,0xF7),
 381                 tpm_read_index(nscAddrBase,0xF8), tpm_read_index(nscAddrBase,0xF9));
 382
 383         dev_info(&pdev->dev,
 384                  "NSC TPM revision %d\n",
 385                  tpm_read_index(nscAddrBase, 0x27) & 0x1F);
 386
 387         return 0;
 388
 389 err_rel_reg:
 390         release_region(base, 2);
 391 err_del_dev:
 392         platform_device_del(pdev);
 393 err_put_dev:
 394         platform_device_put(pdev);
 395 err_unreg_drv:
 396         platform_driver_unregister(&nsc_drv);
 397         return rc;
 398 }
 399
 400 static void __exit cleanup_nsc(void)
 401 {
 402         if (pdev) {
 403                 tpm_nsc_remove(&pdev->dev);
 404                 platform_device_unregister(pdev);
 405         }
 406
 407         platform_driver_unregister(&nsc_drv);
 408 }
 409
 410 module_init(init_nsc);
 411 module_exit(cleanup_nsc);
 412
 413 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
 414 MODULE_DESCRIPTION("TPM Driver");
 415 MODULE_VERSION("2.0");
 416 MODULE_LICENSE("GPL");