drivers/tpm/tpm-uclass.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (c) 2015 Google, Inc
   4  * Written by Simon Glass <[email protected]>
   5  */
   6
   7 #define LOG_CATEGORY UCLASS_TPM
   8
   9 #include <common.h>
  10 #include <dm.h>
  11 #include <log.h>
  12 #include <linux/delay.h>
  13 #include <linux/unaligned/be_byteshift.h>
  14 #include <tpm-v1.h>
  15 #include <tpm-v2.h>
  16 #include "tpm_internal.h"
  17
  18 int tpm_open(struct udevice *dev)
  19 {
  20         struct tpm_ops *ops = tpm_get_ops(dev);
  21
  22         if (!ops->open)
  23                 return -ENOSYS;
  24
  25         return ops->open(dev);
  26 }
  27
  28 int tpm_close(struct udevice *dev)
  29 {
  30         struct tpm_ops *ops = tpm_get_ops(dev);
  31
  32         if (!ops->close)
  33                 return -ENOSYS;
  34
  35         return ops->close(dev);
  36 }
  37
  38 int tpm_get_desc(struct udevice *dev, char *buf, int size)
  39 {
  40         struct tpm_ops *ops = tpm_get_ops(dev);
  41
  42         if (!ops->get_desc)
  43                 return -ENOSYS;
  44
  45         return ops->get_desc(dev, buf, size);
  46 }
  47
  48 /* Returns max number of milliseconds to wait */
  49 static ulong tpm_tis_i2c_calc_ordinal_duration(struct tpm_chip_priv *priv,
  50                                                u32 ordinal)
  51 {
  52         int duration_idx = TPM_UNDEFINED;
  53         int duration = 0;
  54
  55         if (ordinal < TPM_MAX_ORDINAL) {
  56                 duration_idx = tpm_ordinal_duration[ordinal];
  57         } else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
  58                         TPM_MAX_PROTECTED_ORDINAL) {
  59                 duration_idx = tpm_protected_ordinal_duration[
  60                                 ordinal & TPM_PROTECTED_ORDINAL_MASK];
  61         }
  62
  63         if (duration_idx != TPM_UNDEFINED)
  64                 duration = priv->duration_ms[duration_idx];
  65
  66         if (duration <= 0)
  67                 return 2 * 60 * 1000; /* Two minutes timeout */
  68         else
  69                 return duration;
  70 }
  71
  72 int tpm_xfer(struct udevice *dev, const uint8_t *sendbuf, size_t send_size,
  73         uint8_t *recvbuf, size_t *recv_size)
  74 {
  75         struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
  76         struct tpm_ops *ops = tpm_get_ops(dev);
  77         ulong start, stop;
  78         uint count, ordinal;
  79         int ret, ret2 = 0;
  80
  81         if (ops->xfer)
  82                 return ops->xfer(dev, sendbuf, send_size, recvbuf, recv_size);
  83
  84         if (!ops->send || !ops->recv)
  85                 return -ENOSYS;
  86
  87         /* switch endianess: big->little */
  88         count = get_unaligned_be32(sendbuf + TPM_CMD_COUNT_BYTE);
  89         ordinal = get_unaligned_be32(sendbuf + TPM_CMD_ORDINAL_BYTE);
  90
  91         if (count == 0) {
  92                 log_debug("no data\n");
  93                 return -ENODATA;
  94         }
  95         if (count > send_size) {
  96                 log_debug("invalid count value %x %zx\n", count, send_size);
  97                 return -E2BIG;
  98         }
  99
 100         log_debug("%s: Calling send\n", __func__);
 101         ret = ops->send(dev, sendbuf, send_size);
 102         if (ret < 0)
 103                 return ret;
 104
 105         start = get_timer(0);
 106         stop = tpm_tis_i2c_calc_ordinal_duration(priv, ordinal);
 107         do {
 108                 ret = ops->recv(dev, priv->buf, sizeof(priv->buf));
 109                 if (ret >= 0) {
 110                         if (ret > *recv_size)
 111                                 return -ENOSPC;
 112                         memcpy(recvbuf, priv->buf, ret);
 113                         *recv_size = ret;
 114                         ret = 0;
 115                         break;
 116                 } else if (ret != -EAGAIN) {
 117                         return ret;
 118                 }
 119
 120                 mdelay(priv->retry_time_ms);
 121                 if (get_timer(start) > stop) {
 122                         ret = -ETIMEDOUT;
 123                         break;
 124                 }
 125         } while (ret);
 126
 127         if (ret) {
 128                 if (ops->cleanup) {
 129                         ret2 = ops->cleanup(dev);
 130                         if (ret2)
 131                                 return log_msg_ret("cleanup", ret2);
 132                 }
 133                 return log_msg_ret("xfer", ret);
 134         }
 135
 136         return 0;
 137 }
 138
 139 UCLASS_DRIVER(tpm) = {
 140         .id             = UCLASS_TPM,
 141         .name           = "tpm",
 142         .flags          = DM_UC_FLAG_SEQ_ALIAS,
 143 #if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
 144         .post_bind      = dm_scan_fdt_dev,
 145 #endif
 146         .per_device_auto        = sizeof(struct tpm_chip_priv),
 147 };