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 #define LOG_CATEGORY UCLASS_TPM
8
9 #include <common.h>
10 #include <dm.h>
11 #include <log.h>
12 #include <tpm_api.h>
13 #include <tpm-v1.h>
14 #include <tpm-v2.h>
15 #include <dm/lists.h>
16 #include <linux/delay.h>
17 #include <linux/unaligned/be_byteshift.h>
18 #include "tpm_internal.h"
19
tpm_open(struct udevice * dev)20 int tpm_open(struct udevice *dev)
21 {
22 struct tpm_ops *ops = tpm_get_ops(dev);
23
24 if (!ops->open)
25 return -ENOSYS;
26
27 return ops->open(dev);
28 }
29
tpm_close(struct udevice * dev)30 int tpm_close(struct udevice *dev)
31 {
32 struct tpm_ops *ops = tpm_get_ops(dev);
33
34 if (!ops->close)
35 return -ENOSYS;
36
37 return ops->close(dev);
38 }
39
tpm_get_desc(struct udevice * dev,char * buf,int size)40 int tpm_get_desc(struct udevice *dev, char *buf, int size)
41 {
42 struct tpm_ops *ops = tpm_get_ops(dev);
43
44 if (!ops->get_desc)
45 return -ENOSYS;
46
47 return ops->get_desc(dev, buf, size);
48 }
49
tpm_report_state(struct udevice * dev,char * buf,int size)50 int tpm_report_state(struct udevice *dev, char *buf, int size)
51 {
52 struct tpm_ops *ops = tpm_get_ops(dev);
53
54 if (!ops->report_state)
55 return -ENOSYS;
56
57 return ops->report_state(dev, buf, size);
58 }
59
60 /* Returns max number of milliseconds to wait */
tpm_tis_i2c_calc_ordinal_duration(struct tpm_chip_priv * priv,u32 ordinal)61 static ulong tpm_tis_i2c_calc_ordinal_duration(struct tpm_chip_priv *priv,
62 u32 ordinal)
63 {
64 int duration_idx = TPM_UNDEFINED;
65 int duration = 0;
66
67 if (ordinal < TPM_MAX_ORDINAL) {
68 duration_idx = tpm_ordinal_duration[ordinal];
69 } else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
70 TPM_MAX_PROTECTED_ORDINAL) {
71 duration_idx = tpm_protected_ordinal_duration[
72 ordinal & TPM_PROTECTED_ORDINAL_MASK];
73 }
74
75 if (duration_idx != TPM_UNDEFINED)
76 duration = priv->duration_ms[duration_idx];
77
78 if (duration <= 0)
79 return 2 * 60 * 1000; /* Two minutes timeout */
80 else
81 return duration;
82 }
83
tpm_xfer(struct udevice * dev,const uint8_t * sendbuf,size_t send_size,uint8_t * recvbuf,size_t * recv_size)84 int tpm_xfer(struct udevice *dev, const uint8_t *sendbuf, size_t send_size,
85 uint8_t *recvbuf, size_t *recv_size)
86 {
87 struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
88 struct tpm_ops *ops = tpm_get_ops(dev);
89 ulong start, stop;
90 uint count, ordinal;
91 int ret, ret2 = 0;
92
93 if (ops->xfer)
94 return ops->xfer(dev, sendbuf, send_size, recvbuf, recv_size);
95
96 if (!ops->send || !ops->recv)
97 return -ENOSYS;
98
99 /* switch endianess: big->little */
100 count = get_unaligned_be32(sendbuf + TPM_CMD_COUNT_BYTE);
101 ordinal = get_unaligned_be32(sendbuf + TPM_CMD_ORDINAL_BYTE);
102
103 if (count == 0) {
104 log_debug("no data\n");
105 return -ENODATA;
106 }
107 if (count > send_size) {
108 log_debug("invalid count value %x %zx\n", count, send_size);
109 return -E2BIG;
110 }
111
112 log_debug("%s: Calling send\n", __func__);
113 ret = ops->send(dev, sendbuf, send_size);
114 if (ret < 0)
115 return ret;
116
117 start = get_timer(0);
118 stop = tpm_tis_i2c_calc_ordinal_duration(priv, ordinal);
119 do {
120 ret = ops->recv(dev, priv->buf, sizeof(priv->buf));
121 if (ret >= 0) {
122 if (ret > *recv_size)
123 return -ENOSPC;
124 memcpy(recvbuf, priv->buf, ret);
125 *recv_size = ret;
126 ret = 0;
127 break;
128 } else if (ret != -EAGAIN) {
129 return ret;
130 }
131
132 mdelay(priv->retry_time_ms);
133 if (get_timer(start) > stop) {
134 ret = -ETIMEDOUT;
135 break;
136 }
137 } while (ret);
138
139 if (ret) {
140 if (ops->cleanup) {
141 ret2 = ops->cleanup(dev);
142 if (ret2)
143 return log_msg_ret("cleanup", ret2);
144 }
145 return log_msg_ret("xfer", ret);
146 }
147
148 return 0;
149 }
150
151 UCLASS_DRIVER(tpm) = {
152 .id = UCLASS_TPM,
153 .name = "tpm",
154 .flags = DM_UC_FLAG_SEQ_ALIAS,
155 #if CONFIG_IS_ENABLED(OF_REAL)
156 .post_bind = dm_scan_fdt_dev,
157 #endif
158 .per_device_auto_alloc_size = sizeof(struct tpm_chip_priv),
159 };
160