arch/x86/acpi: Add TPM2 table support

* Distinguish between TPM 1.2 and 2.0
  ACPI table support
* Add TPM2 table support for TIS interface only

Change-Id: I030c7ea744bcfe61ebef8d66d1295273b5dccda5
Signed-off-by: Philipp Deppenwiese <zaolin@das-labor.org>
Reviewed-on: https://review.coreboot.org/29181
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Werner Zeh <werner.zeh@siemens.com>
diff --git a/src/arch/x86/acpi.c b/src/arch/x86/acpi.c
index 1b43004..24db7c0 100644
--- a/src/arch/x86/acpi.c
+++ b/src/arch/x86/acpi.c
@@ -308,6 +308,33 @@
 	header->checksum = acpi_checksum((void *)tcpa, header->length);
 }
 
+static void acpi_create_tpm2(acpi_tpm2_t *tpm2)
+{
+	acpi_header_t *header = &(tpm2->header);
+
+	memset((void *)tpm2, 0, sizeof(acpi_tpm2_t));
+
+	/* Fill out header fields. */
+	memcpy(header->signature, "TPM2", 4);
+	memcpy(header->oem_id, OEM_ID, 6);
+	memcpy(header->oem_table_id, ACPI_TABLE_CREATOR, 8);
+	memcpy(header->asl_compiler_id, ASLC, 4);
+
+	header->length = sizeof(acpi_tpm2_t);
+	header->revision = get_acpi_table_revision(TPM2);
+
+	/* Hard to detect for coreboot. Just set it to 0 */
+	tpm2->platform_class = 0;
+	/* Must be set to 0 for TIS interface support */
+	tpm2->control_area = 0;
+	/* coreboot only supports the TIS interface driver. */
+	tpm2->start_method = 6;
+	memset(tpm2->msp, 0, sizeof(tpm2->msp));
+
+	/* Calculate checksum. */
+	header->checksum = acpi_checksum((void *)tpm2, header->length);
+}
+
 static void acpi_ssdt_write_cbtable(void)
 {
 	const struct cbmem_entry *cbtable;
@@ -1030,6 +1057,7 @@
 	acpi_header_t *dsdt_file, *dsdt;
 	acpi_mcfg_t *mcfg;
 	acpi_tcpa_t *tcpa;
+	acpi_tpm2_t *tpm2;
 	acpi_madt_t *madt;
 	struct device *dev;
 	unsigned long fw;
@@ -1163,13 +1191,26 @@
 		acpi_add_table(rsdp, mcfg);
 	}
 
-	printk(BIOS_DEBUG, "ACPI:    * TCPA\n");
-	tcpa = (acpi_tcpa_t *) current;
-	acpi_create_tcpa(tcpa);
-	if (tcpa->header.length >= sizeof(acpi_tcpa_t)) {
-		current += tcpa->header.length;
-		current = acpi_align_current(current);
-		acpi_add_table(rsdp, tcpa);
+	if (IS_ENABLED(CONFIG_TPM1)) {
+		printk(BIOS_DEBUG, "ACPI:    * TCPA\n");
+		tcpa = (acpi_tcpa_t *) current;
+		acpi_create_tcpa(tcpa);
+		if (tcpa->header.length >= sizeof(acpi_tcpa_t)) {
+			current += tcpa->header.length;
+			current = acpi_align_current(current);
+			acpi_add_table(rsdp, tcpa);
+		}
+	}
+
+	if (IS_ENABLED(CONFIG_TPM2)) {
+		printk(BIOS_DEBUG, "ACPI:    * TPM2\n");
+		tpm2 = (acpi_tpm2_t *) current;
+		acpi_create_tpm2(tpm2);
+		if (tpm2->header.length >= sizeof(acpi_tpm2_t)) {
+			current += tpm2->header.length;
+			current = acpi_align_current(current);
+			acpi_add_table(rsdp, tpm2);
+		}
 	}
 
 	printk(BIOS_DEBUG, "ACPI:    * MADT\n");
@@ -1288,6 +1329,8 @@
 		return 1;
 	case TCPA:
 		return 2;
+	case TPM2:
+		return 4;
 	case SSDT: /* ACPI 1.0/2.0: ?, ACPI 3.0/4.0: 2 */
 		return 2;
 	case SRAT:  /* ACPI 1.0: N/A, 2.0: 1, 3.0: 2, 4.0: 3 */