[coreboot-gerrit] Change in coreboot[master]: security/tpm/tss: Add ClearControl Function

[Christian Walter (Code Review)]

Christian Walter has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/38617 )

Change subject: security/tpm/tss: Add ClearControl Function
......................................................................

security/tpm/tss: Add ClearControl Function

Add ClearControl Function which is needed for a follow-up patch.

Change-Id: Ia19185528fd821e420b0bdb424760c93b79523a4
Signed-off-by: Christian Walter 
---
M src/security/tpm/tss.h
M src/security/tpm/tss/tcg-2.0/tss.c
M src/security/tpm/tss/tcg-2.0/tss_structures.h
3 files changed, 27 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/17/38617/1

diff --git a/src/security/tpm/tss.h b/src/security/tpm/tss.h
index 336935d..5237387 100644
--- a/src/security/tpm/tss.h
+++ b/src/security/tpm/tss.h
@@ -171,6 +171,11 @@
 uint32_t tlcl_force_clear(void);

/**
+ * Set Clear Control. The TPM error code is returned.
+ */
+uint32_t tlcl_clear_control(bool disable);
+
+/**
  * Set the bGlobalLock flag, which only a reboot can clear.  The TPM error
  * code is returned.
  */
diff --git a/src/security/tpm/tss/tcg-2.0/tss.c b/src/security/tpm/tss/tcg-2.0/tss.c
index 6bc3096..49a6cea 100644
--- a/src/security/tpm/tss/tcg-2.0/tss.c
+++ b/src/security/tpm/tss/tcg-2.0/tss.c
@@ -170,6 +170,23 @@
    return TPM_SUCCESS;
 }

+uint32_t tlcl_clear_control(bool disable)
+{
+	struct tpm2_response *response;
+	struct tpm2_clear_control_cmd cc = {
+		.disable = 0,
+	};
+
+	response = tpm_process_command(TPM2_ClearControl, &cc);
+	printk(BIOS_INFO, "%s: response is %x\n",
+		__func__, response ? response->hdr.tpm_code : -1);
+
+	if (!response || response->hdr.tpm_code)
+		return TPM_E_IOERROR;
+
+	return TPM_SUCCESS;
+}
+
 static uint8_t tlcl_init_done;

/* This function is called directly by vboot, uses vboot return types. */
diff --git a/src/security/tpm/tss/tcg-2.0/tss_structures.h b/src/security/tpm/tss/tcg-2.0/tss_structures.h
index 1530613..ade9b27 100644
--- a/src/security/tpm/tss/tcg-2.0/tss_structures.h
+++ b/src/security/tpm/tss/tcg-2.0/tss_structures.h
@@ -84,6 +84,7 @@
 /* TPM command codes. */
 #define TPM2_Hierarchy_Control ((TPM_CC)0x00000121)
 #define TPM2_Clear             ((TPM_CC)0x00000126)
+#define TPM2_ClearControl      ((TPM_CC)0x00000127)
 #define TPM2_NV_DefineSpace    ((TPM_CC)0x0000012A)
 #define TPM2_NV_Write          ((TPM_CC)0x00000137)
 #define TPM2_NV_WriteLock      ((TPM_CC)0x00000138)
@@ -417,6 +418,10 @@
    TPML_DIGEST_VALUES digests;
 };

+struct tpm2_clear_control_cmd {
+	TPMI_YES_NO disable;
+};
+
 struct tpm2_hierarchy_control_cmd {
    TPMI_RH_ENABLES enable;
    TPMI_YES_NO state;