xref: /aosp_15_r20/external/coreboot/src/security/tpm/tss/tss.c (revision b9411a12aaaa7e1e6a6fb7c5e057f44ee179a49c)
1 /* SPDX-License-Identifier: BSD-3-Clause */
2 
3 #include <console/console.h>
4 #include <drivers/crb/tpm.h>
5 #include <drivers/i2c/tpm/tpm.h>
6 #include <drivers/pc80/tpm/tpm.h>
7 #include <drivers/spi/tpm/tpm.h>
8 #include <security/tpm/tis.h>
9 #include <security/tpm/tss.h>
10 
11 /*
12  * This unit is meant to dispatch to either TPM1.2 or TPM2.0 TSS implementation
13  * based on TPM family determined on probing during initialization.
14  */
15 
16 enum tpm_family tlcl_tpm_family = TPM_UNKNOWN;
17 
18 tis_sendrecv_fn tlcl_tis_sendrecv;
19 
20 /* Probe for TPM device and choose implementation based on the returned TPM family. */
tlcl_lib_init(void)21 tpm_result_t tlcl_lib_init(void)
22 {
23 	/* Don't probe for TPM more than once per stage. */
24 	static bool init_done;
25 	if (init_done)
26 		return tlcl_tpm_family == TPM_UNKNOWN ? TPM_CB_NO_DEVICE : TPM_SUCCESS;
27 
28 	/* Set right away to make recursion impossible. */
29 	init_done = true;
30 
31 	tlcl_tis_sendrecv = NULL;
32 	if (CONFIG(CRB_TPM))
33 		tlcl_tis_sendrecv = crb_tis_probe(&tlcl_tpm_family);
34 	if (CONFIG(MEMORY_MAPPED_TPM) && tlcl_tis_sendrecv == NULL)
35 		tlcl_tis_sendrecv = pc80_tis_probe(&tlcl_tpm_family);
36 	if (CONFIG(I2C_TPM) && tlcl_tis_sendrecv == NULL)
37 		tlcl_tis_sendrecv = i2c_tis_probe(&tlcl_tpm_family);
38 	if (CONFIG(SPI_TPM) && tlcl_tis_sendrecv == NULL)
39 		tlcl_tis_sendrecv = spi_tis_probe(&tlcl_tpm_family);
40 
41 	if (tlcl_tis_sendrecv == NULL) {
42 		printk(BIOS_ERR, "%s: TIS probe failed\n", __func__);
43 		tlcl_tpm_family = TPM_UNKNOWN;
44 	} else if (tlcl_tpm_family != TPM_1 && tlcl_tpm_family != TPM_2) {
45 		printk(BIOS_ERR, "%s: TIS probe returned incorrect TPM family: %d\n", __func__,
46 		       tlcl_tpm_family);
47 		tlcl_tpm_family = TPM_UNKNOWN;
48 	}
49 
50 	return tlcl_tpm_family == TPM_UNKNOWN ? TPM_CB_NO_DEVICE : TPM_SUCCESS;
51 }
52