LXR uboot/drivers/tpm/tpm_atmel

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Copyright (C) 2013 Guntermann & Drunck, GmbH
   4 *
   5 * Written by Dirk Eibach <dirk.eibach@gdsys.cc>
   6 */
   7
   8#include <common.h>
   9#include <dm.h>
  10#include <tpm-v1.h>
  11#include <i2c.h>
  12#include <asm/unaligned.h>
  13
  14#include "tpm_internal.h"
  15
  16#define ATMEL_TPM_TIMEOUT_MS 5000 /* sufficient for anything but
  17                                     generating/exporting keys */
  18
  19/*
  20 * tpm_atmel_twi_open()
  21 *
  22 * Requests access to locality 0 for the caller. After all commands have been
  23 * completed the caller is supposed to call tis_close().
  24 *
  25 * Returns 0 on success, -1 on failure.
  26 */
  27static int tpm_atmel_twi_open(struct udevice *dev)
  28{
  29        return 0;
  30}
  31
  32/*
  33 * tpm_atmel_twi_close()
  34 *
  35 * terminate the currect session with the TPM by releasing the locked
  36 * locality. Returns 0 on success of -1 on failure (in case lock
  37 * removal did not succeed).
  38 */
  39static int tpm_atmel_twi_close(struct udevice *dev)
  40{
  41        return 0;
  42}
  43
  44/*
  45 * tpm_atmel_twi_get_desc()
  46 *
  47 * @dev:        Device to check
  48 * @buf:        Buffer to put the string
  49 * @size:       Maximum size of buffer
  50 * @return length of string, or -ENOSPC it no space
  51 */
  52static int tpm_atmel_twi_get_desc(struct udevice *dev, char *buf, int size)
  53{
  54        return 0;
  55}
  56
  57/*
  58 * tpm_atmel_twi_xfer()
  59 *
  60 * Send the requested data to the TPM and then try to get its response
  61 *
  62 * @sendbuf - buffer of the data to send
  63 * @send_size size of the data to send
  64 * @recvbuf - memory to save the response to
  65 * @recv_len - pointer to the size of the response buffer
  66 *
  67 * Returns 0 on success (and places the number of response bytes at recv_len)
  68 * or -1 on failure.
  69 */
  70static int tpm_atmel_twi_xfer(struct udevice *dev,
  71                              const uint8_t *sendbuf, size_t send_size,
  72                              uint8_t *recvbuf, size_t *recv_len)
  73{
  74        int res;
  75        unsigned long start;
  76
  77#ifdef DEBUG
  78        memset(recvbuf, 0xcc, *recv_len);
  79        printf("send to TPM (%d bytes, recv_len=%d):\n", send_size, *recv_len);
  80        print_buffer(0, (void *)sendbuf, 1, send_size, 0);
  81#endif
  82
  83#ifndef CONFIG_DM_I2C
  84        res = i2c_write(0x29, 0, 0, (uchar *)sendbuf, send_size);
  85#else
  86        res = dm_i2c_write(dev, 0, sendbuf, send_size);
  87#endif
  88        if (res) {
  89                printf("i2c_write returned %d\n", res);
  90                return -1;
  91        }
  92
  93        start = get_timer(0);
  94#ifndef CONFIG_DM_I2C
  95        while ((res = i2c_read(0x29, 0, 0, recvbuf, 10)))
  96#else
  97        while ((res = dm_i2c_read(dev, 0, recvbuf, 10)))
  98#endif
  99        {
 100                /* TODO Use TIS_TIMEOUT from tpm_tis_infineon.h */
 101                if (get_timer(start) > ATMEL_TPM_TIMEOUT_MS) {
 102                        puts("tpm timed out\n");
 103                        return -1;
 104                }
 105                udelay(100);
 106        }
 107        if (!res) {
 108                unsigned int hdr_recv_len;
 109                hdr_recv_len = get_unaligned_be32(recvbuf + 2);
 110                if (hdr_recv_len < 10) {
 111                        puts("tpm response header too small\n");
 112                        return -1;
 113                } else if (hdr_recv_len > *recv_len) {
 114                        puts("tpm response length is bigger than receive buffer\n");
 115                        return -1;
 116                } else {
 117                        *recv_len = hdr_recv_len;
 118#ifndef CONFIG_DM_I2C
 119                        res = i2c_read(0x29, 0, 0, recvbuf, *recv_len);
 120#else
 121                        res = dm_i2c_read(dev, 0, recvbuf, *recv_len);
 122#endif
 123
 124                }
 125        }
 126        if (res) {
 127                printf("i2c_read returned %d (rlen=%d)\n", res, *recv_len);
 128#ifdef DEBUG
 129                print_buffer(0, recvbuf, 1, *recv_len, 0);
 130#endif
 131        }
 132
 133#ifdef DEBUG
 134        if (!res) {
 135                printf("read from TPM (%d bytes):\n", *recv_len);
 136                print_buffer(0, recvbuf, 1, *recv_len, 0);
 137        }
 138#endif
 139
 140        return res;
 141}
 142
 143static int tpm_atmel_twi_probe(struct udevice *dev)
 144{
 145        return 0;
 146}
 147
 148static const struct udevice_id tpm_atmel_twi_ids[] = {
 149        { .compatible = "atmel,at97sc3204t"},
 150        { }
 151};
 152
 153static const struct tpm_ops tpm_atmel_twi_ops = {
 154        .open = tpm_atmel_twi_open,
 155        .close = tpm_atmel_twi_close,
 156        .xfer = tpm_atmel_twi_xfer,
 157        .get_desc = tpm_atmel_twi_get_desc,
 158};
 159
 160U_BOOT_DRIVER(tpm_atmel_twi) = {
 161        .name = "tpm_atmel_twi",
 162        .id = UCLASS_TPM,
 163        .of_match = tpm_atmel_twi_ids,
 164        .ops = &tpm_atmel_twi_ops,
 165        .probe = tpm_atmel_twi_probe,
 166};
 167