1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (c) 2015 Google, Inc
4 * Written by Simon Glass <sjg@chromium.org>
5 */
6
7 #include <common.h>
8 #include <dm.h>
9 #include <linux/unaligned/be_byteshift.h>
10 #if defined(CONFIG_TPM_V1)
11 #include <tpm-v1.h>
12 #elif defined(CONFIG_TPM_V2)
13 #include <tpm-v2.h>
14 #endif
15 #include "tpm_internal.h"
16
tpm_open(struct udevice * dev)17 int tpm_open(struct udevice *dev)
18 {
19 struct tpm_ops *ops = tpm_get_ops(dev);
20
21 if (!ops->open)
22 return -ENOSYS;
23
24 return ops->open(dev);
25 }
26
tpm_close(struct udevice * dev)27 int tpm_close(struct udevice *dev)
28 {
29 struct tpm_ops *ops = tpm_get_ops(dev);
30
31 if (!ops->close)
32 return -ENOSYS;
33
34 return ops->close(dev);
35 }
36
tpm_get_desc(struct udevice * dev,char * buf,int size)37 int tpm_get_desc(struct udevice *dev, char *buf, int size)
38 {
39 struct tpm_ops *ops = tpm_get_ops(dev);
40
41 if (!ops->get_desc)
42 return -ENOSYS;
43
44 return ops->get_desc(dev, buf, size);
45 }
46
47 /* Returns max number of milliseconds to wait */
tpm_tis_i2c_calc_ordinal_duration(struct tpm_chip_priv * priv,u32 ordinal)48 static ulong tpm_tis_i2c_calc_ordinal_duration(struct tpm_chip_priv *priv,
49 u32 ordinal)
50 {
51 int duration_idx = TPM_UNDEFINED;
52 int duration = 0;
53
54 if (ordinal < TPM_MAX_ORDINAL) {
55 duration_idx = tpm_ordinal_duration[ordinal];
56 } else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
57 TPM_MAX_PROTECTED_ORDINAL) {
58 duration_idx = tpm_protected_ordinal_duration[
59 ordinal & TPM_PROTECTED_ORDINAL_MASK];
60 }
61
62 if (duration_idx != TPM_UNDEFINED)
63 duration = priv->duration_ms[duration_idx];
64
65 if (duration <= 0)
66 return 2 * 60 * 1000; /* Two minutes timeout */
67 else
68 return duration;
69 }
70
tpm_xfer(struct udevice * dev,const uint8_t * sendbuf,size_t send_size,uint8_t * recvbuf,size_t * recv_size)71 int tpm_xfer(struct udevice *dev, const uint8_t *sendbuf, size_t send_size,
72 uint8_t *recvbuf, size_t *recv_size)
73 {
74 struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
75 struct tpm_ops *ops = tpm_get_ops(dev);
76 ulong start, stop;
77 uint count, ordinal;
78 int ret, ret2;
79
80 if (ops->xfer)
81 return ops->xfer(dev, sendbuf, send_size, recvbuf, recv_size);
82
83 if (!ops->send || !ops->recv)
84 return -ENOSYS;
85
86 /* switch endianess: big->little */
87 count = get_unaligned_be32(sendbuf + TPM_CMD_COUNT_BYTE);
88 ordinal = get_unaligned_be32(sendbuf + TPM_CMD_ORDINAL_BYTE);
89
90 if (count == 0) {
91 debug("no data\n");
92 return -ENODATA;
93 }
94 if (count > send_size) {
95 debug("invalid count value %x %zx\n", count, send_size);
96 return -E2BIG;
97 }
98
99 debug("%s: Calling send\n", __func__);
100 ret = ops->send(dev, sendbuf, send_size);
101 if (ret < 0)
102 return ret;
103
104 start = get_timer(0);
105 stop = tpm_tis_i2c_calc_ordinal_duration(priv, ordinal);
106 do {
107 ret = ops->recv(dev, priv->buf, sizeof(priv->buf));
108 if (ret >= 0) {
109 if (ret > *recv_size)
110 return -ENOSPC;
111 memcpy(recvbuf, priv->buf, ret);
112 *recv_size = ret;
113 ret = 0;
114 break;
115 } else if (ret != -EAGAIN) {
116 return ret;
117 }
118
119 mdelay(priv->retry_time_ms);
120 if (get_timer(start) > stop) {
121 ret = -ETIMEDOUT;
122 break;
123 }
124 } while (ret);
125
126 ret2 = ops->cleanup ? ops->cleanup(dev) : 0;
127
128 return ret2 ? ret2 : ret;
129 }
130
131 UCLASS_DRIVER(tpm) = {
132 .id = UCLASS_TPM,
133 .name = "tpm",
134 .flags = DM_UC_FLAG_SEQ_ALIAS,
135 .per_device_auto_alloc_size = sizeof(struct tpm_chip_priv),
136 };
137