linux/drivers/char/tpm/tpm_nsc.c
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   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->dev, "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->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
 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->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
 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        if ( chip ) {
 251                release_region(chip->vendor.base, 2);
 252                tpm_remove_hardware(chip->dev);
 253        }
 254}
 255
 256static SIMPLE_DEV_PM_OPS(tpm_nsc_pm, tpm_pm_suspend, tpm_pm_resume);
 257
 258static struct platform_driver nsc_drv = {
 259        .driver          = {
 260                .name    = "tpm_nsc",
 261                .owner   = THIS_MODULE,
 262                .pm      = &tpm_nsc_pm,
 263        },
 264};
 265
 266static int __init init_nsc(void)
 267{
 268        int rc = 0;
 269        int lo, hi, err;
 270        int nscAddrBase = TPM_ADDR;
 271        struct tpm_chip *chip;
 272        unsigned long base;
 273
 274        /* verify that it is a National part (SID) */
 275        if (tpm_read_index(TPM_ADDR, NSC_SID_INDEX) != 0xEF) {
 276                nscAddrBase = (tpm_read_index(TPM_SUPERIO_ADDR, 0x2C)<<8)|
 277                        (tpm_read_index(TPM_SUPERIO_ADDR, 0x2B)&0xFE);
 278                if (tpm_read_index(nscAddrBase, NSC_SID_INDEX) != 0xF6)
 279                        return -ENODEV;
 280        }
 281
 282        err = platform_driver_register(&nsc_drv);
 283        if (err)
 284                return err;
 285
 286        hi = tpm_read_index(nscAddrBase, TPM_NSC_BASE0_HI);
 287        lo = tpm_read_index(nscAddrBase, TPM_NSC_BASE0_LO);
 288        base = (hi<<8) | lo;
 289
 290        /* enable the DPM module */
 291        tpm_write_index(nscAddrBase, NSC_LDC_INDEX, 0x01);
 292
 293        pdev = platform_device_alloc("tpm_nscl0", -1);
 294        if (!pdev) {
 295                rc = -ENOMEM;
 296                goto err_unreg_drv;
 297        }
 298
 299        pdev->num_resources = 0;
 300        pdev->dev.driver = &nsc_drv.driver;
 301        pdev->dev.release = tpm_nsc_remove;
 302
 303        if ((rc = platform_device_add(pdev)) < 0)
 304                goto err_put_dev;
 305
 306        if (request_region(base, 2, "tpm_nsc0") == NULL ) {
 307                rc = -EBUSY;
 308                goto err_del_dev;
 309        }
 310
 311        if (!(chip = tpm_register_hardware(&pdev->dev, &tpm_nsc))) {
 312                rc = -ENODEV;
 313                goto err_rel_reg;
 314        }
 315
 316        dev_dbg(&pdev->dev, "NSC TPM detected\n");
 317        dev_dbg(&pdev->dev,
 318                "NSC LDN 0x%x, SID 0x%x, SRID 0x%x\n",
 319                tpm_read_index(nscAddrBase,0x07), tpm_read_index(nscAddrBase,0x20),
 320                tpm_read_index(nscAddrBase,0x27));
 321        dev_dbg(&pdev->dev,
 322                "NSC SIOCF1 0x%x SIOCF5 0x%x SIOCF6 0x%x SIOCF8 0x%x\n",
 323                tpm_read_index(nscAddrBase,0x21), tpm_read_index(nscAddrBase,0x25),
 324                tpm_read_index(nscAddrBase,0x26), tpm_read_index(nscAddrBase,0x28));
 325        dev_dbg(&pdev->dev, "NSC IO Base0 0x%x\n",
 326                (tpm_read_index(nscAddrBase,0x60) << 8) | tpm_read_index(nscAddrBase,0x61));
 327        dev_dbg(&pdev->dev, "NSC IO Base1 0x%x\n",
 328                (tpm_read_index(nscAddrBase,0x62) << 8) | tpm_read_index(nscAddrBase,0x63));
 329        dev_dbg(&pdev->dev, "NSC Interrupt number and wakeup 0x%x\n",
 330                tpm_read_index(nscAddrBase,0x70));
 331        dev_dbg(&pdev->dev, "NSC IRQ type select 0x%x\n",
 332                tpm_read_index(nscAddrBase,0x71));
 333        dev_dbg(&pdev->dev,
 334                "NSC DMA channel select0 0x%x, select1 0x%x\n",
 335                tpm_read_index(nscAddrBase,0x74), tpm_read_index(nscAddrBase,0x75));
 336        dev_dbg(&pdev->dev,
 337                "NSC Config "
 338                "0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x\n",
 339                tpm_read_index(nscAddrBase,0xF0), tpm_read_index(nscAddrBase,0xF1),
 340                tpm_read_index(nscAddrBase,0xF2), tpm_read_index(nscAddrBase,0xF3),
 341                tpm_read_index(nscAddrBase,0xF4), tpm_read_index(nscAddrBase,0xF5),
 342                tpm_read_index(nscAddrBase,0xF6), tpm_read_index(nscAddrBase,0xF7),
 343                tpm_read_index(nscAddrBase,0xF8), tpm_read_index(nscAddrBase,0xF9));
 344
 345        dev_info(&pdev->dev,
 346                 "NSC TPM revision %d\n",
 347                 tpm_read_index(nscAddrBase, 0x27) & 0x1F);
 348
 349        chip->vendor.base = base;
 350
 351        return 0;
 352
 353err_rel_reg:
 354        release_region(base, 2);
 355err_del_dev:
 356        platform_device_del(pdev);
 357err_put_dev:
 358        platform_device_put(pdev);
 359err_unreg_drv:
 360        platform_driver_unregister(&nsc_drv);
 361        return rc;
 362}
 363
 364static void __exit cleanup_nsc(void)
 365{
 366        if (pdev) {
 367                tpm_nsc_remove(&pdev->dev);
 368                platform_device_unregister(pdev);
 369        }
 370
 371        platform_driver_unregister(&nsc_drv);
 372}
 373
 374module_init(init_nsc);
 375module_exit(cleanup_nsc);
 376
 377MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
 378MODULE_DESCRIPTION("TPM Driver");
 379MODULE_VERSION("2.0");
 380MODULE_LICENSE("GPL");
 381