1 files changed, 39 insertions, 0 deletions
diff --git a/src/security/tpm/tss/tss.c b/src/security/tpm/tss/tss.c
new file mode 100644
index 0000000000..bd0e98582b
--- /dev/null
+++ b/src/security/tpm/tss/tss.c
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#include <console/console.h>
+#include <security/tpm/tis.h>
+#include <security/tpm/tss.h>
+
+/*
+ * This unit is meant to dispatch to either TPM1.2 or TPM2.0 TSS implementation
+ * based on TPM family determined on probing during initialization.
+ */
+
+enum tpm_family tlcl_tpm_family = TPM_UNKNOWN;
+
+tis_sendrecv_fn tlcl_tis_sendrecv;
+
+/* Probe for TPM device and choose implementation based on the returned TPM family. */
+tpm_result_t tlcl_lib_init(void)
+{
+	/* Don't probe for TPM more than once per stage. */
+	static bool init_done;
+	if (init_done)
+		return tlcl_tpm_family == TPM_UNKNOWN ? TPM_CB_NO_DEVICE : TPM_SUCCESS;
+
+	/* Set right away to make recursion impossible. */
+	init_done = true;
+
+	tlcl_tis_sendrecv = tis_probe(&tlcl_tpm_family);
+
+	if (tlcl_tis_sendrecv == NULL) {
+		printk(BIOS_ERR, "%s: tis_probe failed\n", __func__);
+		tlcl_tpm_family = TPM_UNKNOWN;
+	} else if (tlcl_tpm_family != TPM_1 && tlcl_tpm_family != TPM_2) {
+		printk(BIOS_ERR, "%s: tis_probe returned incorrect TPM family: %d\n", __func__,
+		       tlcl_tpm_family);
+		tlcl_tpm_family = TPM_UNKNOWN;
+	}
+
+	return tlcl_tpm_family == TPM_UNKNOWN ? TPM_CB_NO_DEVICE : TPM_SUCCESS;
+}