diff options
Diffstat (limited to 'drivers/crypto/atmel-ecc.h')
| -rw-r--r-- | drivers/crypto/atmel-ecc.h | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/drivers/crypto/atmel-ecc.h b/drivers/crypto/atmel-ecc.h new file mode 100644 index 000000000..25232c8ab --- /dev/null +++ b/drivers/crypto/atmel-ecc.h @@ -0,0 +1,128 @@ +/* + * Copyright (c) 2017, Microchip Technology Inc. + * Author: Tudor Ambarus <tudor.ambarus@microchip.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + * + */ + +#ifndef __ATMEL_ECC_H__ +#define __ATMEL_ECC_H__ + +#define ATMEL_ECC_PRIORITY 300 + +#define COMMAND 0x03 /* packet function */ +#define SLEEP_TOKEN 0x01 +#define WAKE_TOKEN_MAX_SIZE 8 + +/* Definitions of Data and Command sizes */ +#define WORD_ADDR_SIZE 1 +#define COUNT_SIZE 1 +#define CRC_SIZE 2 +#define CMD_OVERHEAD_SIZE (COUNT_SIZE + CRC_SIZE) + +/* size in bytes of the n prime */ +#define ATMEL_ECC_NIST_P256_N_SIZE 32 +#define ATMEL_ECC_PUBKEY_SIZE (2 * ATMEL_ECC_NIST_P256_N_SIZE) + +#define STATUS_RSP_SIZE 4 +#define ECDH_RSP_SIZE (32 + CMD_OVERHEAD_SIZE) +#define GENKEY_RSP_SIZE (ATMEL_ECC_PUBKEY_SIZE + \ + CMD_OVERHEAD_SIZE) +#define READ_RSP_SIZE (4 + CMD_OVERHEAD_SIZE) +#define MAX_RSP_SIZE GENKEY_RSP_SIZE + +/** + * atmel_ecc_cmd - structure used for communicating with the device. + * @word_addr: indicates the function of the packet sent to the device. This + * byte should have a value of COMMAND for normal operation. + * @count : number of bytes to be transferred to (or from) the device. + * @opcode : the command code. + * @param1 : the first parameter; always present. + * @param2 : the second parameter; always present. + * @data : optional remaining input data. Includes a 2-byte CRC. + * @rxsize : size of the data received from i2c client. + * @msecs : command execution time in milliseconds + */ +struct atmel_ecc_cmd { + u8 word_addr; + u8 count; + u8 opcode; + u8 param1; + u16 param2; + u8 data[MAX_RSP_SIZE]; + u8 msecs; + u16 rxsize; +} __packed; + +/* Status/Error codes */ +#define STATUS_SIZE 0x04 +#define STATUS_NOERR 0x00 +#define STATUS_WAKE_SUCCESSFUL 0x11 + +static const struct { + u8 value; + const char *error_text; +} error_list[] = { + { 0x01, "CheckMac or Verify miscompare" }, + { 0x03, "Parse Error" }, + { 0x05, "ECC Fault" }, + { 0x0F, "Execution Error" }, + { 0xEE, "Watchdog about to expire" }, + { 0xFF, "CRC or other communication error" }, +}; + +/* Definitions for eeprom organization */ +#define CONFIG_ZONE 0 + +/* Definitions for Indexes common to all commands */ +#define RSP_DATA_IDX 1 /* buffer index of data in response */ +#define DATA_SLOT_2 2 /* used for ECDH private key */ + +/* Definitions for the device lock state */ +#define DEVICE_LOCK_ADDR 0x15 +#define LOCK_VALUE_IDX (RSP_DATA_IDX + 2) +#define LOCK_CONFIG_IDX (RSP_DATA_IDX + 3) + +/* + * Wake High delay to data communication (microseconds). SDA should be stable + * high for this entire duration. + */ +#define TWHI_MIN 1500 +#define TWHI_MAX 1550 + +/* Wake Low duration */ +#define TWLO_USEC 60 + +/* Command execution time (milliseconds) */ +#define MAX_EXEC_TIME_ECDH 58 +#define MAX_EXEC_TIME_GENKEY 115 +#define MAX_EXEC_TIME_READ 1 + +/* Command opcode */ +#define OPCODE_ECDH 0x43 +#define OPCODE_GENKEY 0x40 +#define OPCODE_READ 0x02 + +/* Definitions for the READ Command */ +#define READ_COUNT 7 + +/* Definitions for the GenKey Command */ +#define GENKEY_COUNT 7 +#define GENKEY_MODE_PRIVATE 0x04 + +/* Definitions for the ECDH Command */ +#define ECDH_COUNT 71 +#define ECDH_PREFIX_MODE 0x00 + +#endif /* __ATMEL_ECC_H__ */ |