diff options
Diffstat (limited to 'include/tpm.h')
| -rw-r--r-- | include/tpm.h | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/include/tpm.h b/include/tpm.h index 88aeba2..e4472d3 100644 --- a/include/tpm.h +++ b/include/tpm.h @@ -15,6 +15,17 @@ * Specification for definitions of TPM commands. */ +#define TPM_HEADER_SIZE 10 + +enum tpm_duration { + TPM_SHORT = 0, + TPM_MEDIUM = 1, + TPM_LONG = 2, + TPM_UNDEFINED, + + TPM_DURATION_COUNT, +}; + enum tpm_startup_type { TPM_ST_CLEAR = 0x0001, TPM_ST_STATE = 0x0002, @@ -152,6 +163,187 @@ enum tpm_return_code { TPM_DEFEND_LOCK_RUNNING = TPM_BASE + TPM_NON_FATAL + 3, }; +#ifdef CONFIG_DM_TPM + +/* Max buffer size supported by our tpm */ +#define TPM_DEV_BUFSIZE 1260 + +/** + * struct tpm_chip_priv - Information about a TPM, stored by the uclass + * + * These values must be set up by the device's probe() method before + * communcation is attempted. If the device has an xfer() method, this is + * not needed. There is no need to set up @buf. + * + * @duration_ms: Length of each duration type in milliseconds + * @retry_time_ms: Time to wait before retrying receive + */ +struct tpm_chip_priv { + uint duration_ms[TPM_DURATION_COUNT]; + uint retry_time_ms; + u8 buf[TPM_DEV_BUFSIZE + sizeof(u8)]; /* Max buffer size + addr */ +}; + +/** + * struct tpm_ops - low-level TPM operations + * + * These are designed to avoid loops and delays in the driver itself. These + * should be handled in the uclass. + * + * In gneral you should implement everything except xfer(). Where you need + * complete control of the transfer, then xfer() can be provided and will + * override the other methods. + * + * This interface is for low-level TPM access. It does not understand the + * concept of localities or the various TPM messages. That interface is + * defined in the functions later on in this file, but they all translate + * to bytes which are sent and received. + */ +struct tpm_ops { + /** + * open() - Request access to locality 0 for the caller + * + * After all commands have been completed the caller should call + * close(). + * + * @dev: Device to close + * @return 0 ok OK, -ve on error + */ + int (*open)(struct udevice *dev); + + /** + * close() - Close the current session + * + * Releasing the locked locality. Returns 0 on success, -ve 1 on + * failure (in case lock removal did not succeed). + * + * @dev: Device to close + * @return 0 ok OK, -ve on error + */ + int (*close)(struct udevice *dev); + + /** + * get_desc() - Get a text description of the TPM + * + * @dev: Device to check + * @buf: Buffer to put the string + * @size: Maximum size of buffer + * @return length of string, or -ENOSPC it no space + */ + int (*get_desc)(struct udevice *dev, char *buf, int size); + + /** + * send() - send data to the TPM + * + * @dev: Device to talk to + * @sendbuf: Buffer of the data to send + * @send_size: Size of the data to send + * + * Returns 0 on success or -ve on failure. + */ + int (*send)(struct udevice *dev, const uint8_t *sendbuf, + size_t send_size); + + /** + * recv() - receive a response from the TPM + * + * @dev: Device to talk to + * @recvbuf: Buffer to save the response to + * @max_size: Maximum number of bytes to receive + * + * Returns number of bytes received on success, -EAGAIN if the TPM + * response is not ready, -EINTR if cancelled, or other -ve value on + * failure. + */ + int (*recv)(struct udevice *dev, uint8_t *recvbuf, size_t max_size); + + /** + * cleanup() - clean up after an operation in progress + * + * This is called if receiving times out. The TPM may need to abort + * the current transaction if it did not complete, and make itself + * ready for another. + * + * @dev: Device to talk to + */ + int (*cleanup)(struct udevice *dev); + + /** + * xfer() - send data to the TPM and get response + * + * This method is optional. If it exists it is used in preference + * to send(), recv() and cleanup(). It should handle all aspects of + * TPM communication for a single transfer. + * + * @dev: Device to talk to + * @sendbuf: Buffer of the data to send + * @send_size: Size of the data to send + * @recvbuf: Buffer to save the response to + * @recv_size: Pointer to the size of the response buffer + * + * Returns 0 on success (and places the number of response bytes at + * recv_size) or -ve on failure. + */ + int (*xfer)(struct udevice *dev, const uint8_t *sendbuf, + size_t send_size, uint8_t *recvbuf, size_t *recv_size); +}; + +#define tpm_get_ops(dev) ((struct tpm_ops *)device_get_ops(dev)) + +/** + * tpm_open() - Request access to locality 0 for the caller + * + * After all commands have been completed the caller is supposed to + * call tpm_close(). + * + * Returns 0 on success, -ve on failure. + */ +int tpm_open(struct udevice *dev); + +/** + * tpm_close() - Close the current session + * + * Releasing the locked locality. Returns 0 on success, -ve 1 on + * failure (in case lock removal did not succeed). + */ +int tpm_close(struct udevice *dev); + +/** + * tpm_get_desc() - Get a text description of the TPM + * + * @dev: Device to check + * @buf: Buffer to put the string + * @size: Maximum size of buffer + * @return length of string, or -ENOSPC it no space + */ +int tpm_get_desc(struct udevice *dev, char *buf, int size); + +/** + * tpm_xfer() - send data to the TPM and get response + * + * This first uses the device's send() method to send the bytes. Then it calls + * recv() to get the reply. If recv() returns -EAGAIN then it will delay a + * short time and then call recv() again. + * + * Regardless of whether recv() completes successfully, it will then call + * cleanup() to finish the transaction. + * + * Note that the outgoing data is inspected to determine command type + * (ordinal) and a timeout is used for that command type. + * + * @sendbuf - buffer of the data to send + * @send_size size of the data to send + * @recvbuf - memory to save the response to + * @recv_len - pointer to the size of the response buffer + * + * Returns 0 on success (and places the number of response bytes at + * recv_len) or -ve on failure. + */ +int tpm_xfer(struct udevice *dev, const uint8_t *sendbuf, size_t send_size, + uint8_t *recvbuf, size_t *recv_size); + +#endif /* CONFIG_DM_TPM */ + /** * Initialize TPM device. It must be called before any TPM commands. * |