From: Dirk Eibach eibach@gdsys.de
Add support for Atmel TPM devices with two wire interface.
Signed-off-by: Dirk Eibach eibach@gdsys.cc Signed-off-by: Reinhard Pfau pfau@gdsys.cc Signed-off-by: Dirk Eibach dirk.eibach@gdsys.cc --- Changes in v2: None
README | 6 ++ drivers/tpm/Makefile | 1 + drivers/tpm/atmel_twi_tpm.c | 119 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 126 insertions(+), 0 deletions(-) create mode 100644 drivers/tpm/atmel_twi_tpm.c
diff --git a/README b/README index 58b2ee5..2053931 100644 --- a/README +++ b/README @@ -1201,6 +1201,12 @@ The following options need to be configured: If this option is set, the driver enables cache flush.
- TPM Support: + Only one TPM device per system is supported at this time. + So enable only one of the supported devices. + + CONFIG_ATMEL_TWI_TPM + Support for Atmel TWI TPM device. Requires I2C support. + CONFIG_GENERIC_LPC_TPM Support for generic parallel port TPM devices. Only one device per system is supported at this time. diff --git a/drivers/tpm/Makefile b/drivers/tpm/Makefile index e8c159c..5c8f246 100644 --- a/drivers/tpm/Makefile +++ b/drivers/tpm/Makefile @@ -28,6 +28,7 @@ $(shell mkdir -p $(obj)slb9635_i2c) COBJS-$(CONFIG_GENERIC_LPC_TPM) = generic_lpc_tpm.o COBJS-$(CONFIG_INFINEON_TPM_I2C) += tis_i2c.o slb9635_i2c/tpm.o COBJS-$(CONFIG_INFINEON_TPM_I2C) += slb9635_i2c/tpm_tis_i2c.o +COBJS-$(CONFIG_ATMEL_TWI_TPM) = atmel_twi_tpm.o
COBJS := $(COBJS-y) SRCS := $(COBJS:.o=.c) diff --git a/drivers/tpm/atmel_twi_tpm.c b/drivers/tpm/atmel_twi_tpm.c new file mode 100644 index 0000000..1fa626f --- /dev/null +++ b/drivers/tpm/atmel_twi_tpm.c @@ -0,0 +1,119 @@ +/* + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * 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, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> +#include <tpm.h> +#include <i2c.h> +#include <asm/unaligned.h> + +#undef DEBUG_ATMEL_TWI_TPM +#ifdef DEBUG +#define DEBUG_ATMEL_TWI_TPM +#endif + + +/* + * tis_init() + * + * Initialize the TPM device. Returns 0 on success or -1 on + * failure (in case device probing did not succeed). + */ +int tis_init(void) +{ + return 0; +} + +/* + * tis_open() + * + * Requests access to locality 0 for the caller. After all commands have been + * completed the caller is supposed to call tis_close(). + * + * Returns 0 on success, -1 on failure. + */ +int tis_open(void) +{ + return 0; +} + +/* + * tis_close() + * + * terminate the currect session with the TPM by releasing the locked + * locality. Returns 0 on success of -1 on failure (in case lock + * removal did not succeed). + */ +int tis_close(void) +{ + return 0; +} + +/* + * tis_sendrecv() + * + * Send the requested data to the TPM and then try to get its response + * + * @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 -1 on failure. + */ +int tis_sendrecv(const uint8_t *sendbuf, size_t send_size, uint8_t *recvbuf, + size_t *recv_len) +{ + int res; + +#ifdef DEBUG_ATMEL_TWI_TPM + memset(recvbuf, 0xcc, *recv_len); + printf("send to TPM (%d bytes, recv_len=%d):\n", send_size, *recv_len); + print_buffer(0, (void *)sendbuf, 1, send_size, 0); +#endif + + res = i2c_write(0x29, 0, 0, (uchar *)sendbuf, send_size); + if (res) { + printf("i2c_write returned %d\n", res); + return -1; + } + + mdelay(1); + /* TODO timeout for the loop?! */ + while ((res = i2c_read(0x29, 0, 0, recvbuf, 10))) + udelay(100); + if (!res) { + *recv_len = get_unaligned_be32(recvbuf + 2); + if (*recv_len > 10) + res = i2c_read(0x29, 0, 0, recvbuf, *recv_len); + } + if (res) { + printf("i2c_read returned %d (rlen=%d)\n", res, *recv_len); +#ifdef DEBUG_ATMEL_TWI_TPM + print_buffer(0, recvbuf, 1, *recv_len, 0); +#endif + } + +#ifdef DEBUG_ATMEL_TWI_TPM + if (!res) { + printf("read from TPM (%d bytes):\n", *recv_len); + print_buffer(0, recvbuf, 1, *recv_len, 0); + } +#endif + + return res; +}