[U-Boot] [PATCH v2 5/7] Add Atmel I2C tpm

[Dirk Eibach]

From: Dirk Eibach <eibach at gdsys.de>

Add support for Atmel TPM devices with two wire interface.

Signed-off-by: Dirk Eibach <eibach at gdsys.cc>
Signed-off-by: Reinhard Pfau <pfau at gdsys.cc>
Signed-off-by: Dirk Eibach <dirk.eibach at 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;
+}
-- 
1.7.2.5