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 */ 27 static 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 */ 39 static 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 */ 52 static 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 */ 70 static 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 } 142 143 static int tpm_atmel_twi_probe(struct udevice *dev) 144 { 145 return 0; 146 } 147 148 static const struct udevice_id tpm_atmel_twi_ids[] = { 149 { .compatible = "atmel,at97sc3204t"}, 150 { } 151 }; 152 153 static 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 }; 159 160 U_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