[PATCH v2 1/6] tpm: add TPM2_Shutdown command

[Raymond Mao]

TPM2_shutdown command is sharing same structure and logics with
TPM2_startup, thus this patch extends the existing startup APIs and
cmd functions to support shutdown instead of created new ones.

Signed-off-by: Raymond Mao <raymond.mao at linaro.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>
---
changes in v2
- None.

 cmd/tpm-v2.c     | 14 +++++++++++---
 include/tpm-v2.h |  3 ++-
 lib/tpm-v2.c     |  9 +++++----
 lib/tpm_api.c    |  4 ++--
 4 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/cmd/tpm-v2.c b/cmd/tpm-v2.c
index 8517833f86..a6d57ee7c4 100644
--- a/cmd/tpm-v2.c
+++ b/cmd/tpm-v2.c
@@ -18,11 +18,14 @@ static int do_tpm2_startup(struct cmd_tbl *cmdtp, int flag, int argc,
 	enum tpm2_startup_types mode;
 	struct udevice *dev;
 	int ret;
+	bool bon = true;
 
 	ret = get_tpm(&dev);
 	if (ret)
 		return ret;
-	if (argc != 2)
+
+	/* argv[2] is optional to perform a TPM2_CC_SHUTDOWN */
+	if (argc > 3 || (argc == 3 && strcasecmp("off", argv[2])))
 		return CMD_RET_USAGE;
 
 	if (!strcasecmp("TPM2_SU_CLEAR", argv[1])) {
@@ -34,7 +37,10 @@ static int do_tpm2_startup(struct cmd_tbl *cmdtp, int flag, int argc,
 		return CMD_RET_FAILURE;
 	}
 
-	return report_return_code(tpm2_startup(dev, mode));
+	if (argv[2])
+		bon = false;
+
+	return report_return_code(tpm2_startup(dev, bon, mode));
 }
 
 static int do_tpm2_self_test(struct cmd_tbl *cmdtp, int flag, int argc,
@@ -420,11 +426,13 @@ U_BOOT_CMD(tpm2, CONFIG_SYS_MAXARGS, 1, do_tpm, "Issue a TPMv2.x command",
 "    Initialize the software stack. Always the first command to issue.\n"
 "    'tpm startup' is the only acceptable command after a 'tpm init' has been\n"
 "    issued\n"
-"startup <mode>\n"
+"startup <mode> [<op>]\n"
 "    Issue a TPM2_Startup command.\n"
 "    <mode> is one of:\n"
 "        * TPM2_SU_CLEAR (reset state)\n"
 "        * TPM2_SU_STATE (preserved state)\n"
+"    <op>:\n"
+"        * off - To shutdown the TPM\n"
 "self_test <type>\n"
 "    Test the TPM capabilities.\n"
 "    <type> is one of:\n"
diff --git a/include/tpm-v2.h b/include/tpm-v2.h
index 65681464b3..f66a8e1bf4 100644
--- a/include/tpm-v2.h
+++ b/include/tpm-v2.h
@@ -230,6 +230,7 @@ enum tpm2_command_codes {
 	TPM2_CC_PCR_READ	= 0x017E,
 	TPM2_CC_PCR_EXTEND	= 0x0182,
 	TPM2_CC_PCR_SETAUTHVAL	= 0x0183,
+	TPM2_CC_SHUTDOWN	= 0x0145,
 };
 
 /**
@@ -430,7 +431,7 @@ enum {
  *
  * Return: code of the operation
  */
-u32 tpm2_startup(struct udevice *dev, enum tpm2_startup_types mode);
+u32 tpm2_startup(struct udevice *dev, bool onoff, enum tpm2_startup_types mode);
 
 /**
  * Issue a TPM2_SelfTest command.
diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c
index bc750b7ca1..3946ac2dbb 100644
--- a/lib/tpm-v2.c
+++ b/lib/tpm-v2.c
@@ -44,12 +44,13 @@ static int tpm2_update_active_banks(struct udevice *dev)
 	return 0;
 }
 
-u32 tpm2_startup(struct udevice *dev, enum tpm2_startup_types mode)
+u32 tpm2_startup(struct udevice *dev, bool bon, enum tpm2_startup_types mode)
 {
+	int op = bon ? TPM2_CC_STARTUP : TPM2_CC_SHUTDOWN;
 	const u8 command_v2[12] = {
 		tpm_u16(TPM2_ST_NO_SESSIONS),
 		tpm_u32(12),
-		tpm_u32(TPM2_CC_STARTUP),
+		tpm_u32(op),
 		tpm_u16(mode),
 	};
 	int ret;
@@ -59,7 +60,7 @@ u32 tpm2_startup(struct udevice *dev, enum tpm2_startup_types mode)
 	 * but will return RC_INITIALIZE otherwise.
 	 */
 	ret = tpm_sendrecv_command(dev, command_v2, NULL, NULL);
-	if (ret && ret != TPM2_RC_INITIALIZE)
+	if ((ret && ret != TPM2_RC_INITIALIZE) || !bon)
 		return ret;
 
 	return tpm2_update_active_banks(dev);
@@ -84,7 +85,7 @@ u32 tpm2_auto_start(struct udevice *dev)
 	rc = tpm2_self_test(dev, TPMI_YES);
 
 	if (rc == TPM2_RC_INITIALIZE) {
-		rc = tpm2_startup(dev, TPM2_SU_CLEAR);
+		rc = tpm2_startup(dev, true, TPM2_SU_CLEAR);
 		if (rc)
 			return rc;
 
diff --git a/lib/tpm_api.c b/lib/tpm_api.c
index 39a5121e30..576d601e5f 100644
--- a/lib/tpm_api.c
+++ b/lib/tpm_api.c
@@ -28,7 +28,7 @@ u32 tpm_startup(struct udevice *dev, enum tpm_startup_type mode)
 		case TPM_ST_DEACTIVATED:
 			return -EINVAL;
 		}
-		return tpm2_startup(dev, type);
+		return tpm2_startup(dev, true, type);
 	} else {
 		return -ENOSYS;
 	}
@@ -60,7 +60,7 @@ u32 tpm_resume(struct udevice *dev)
 	if (tpm_is_v1(dev))
 		return tpm1_startup(dev, TPM_ST_STATE);
 	else if (tpm_is_v2(dev))
-		return tpm2_startup(dev, TPM2_SU_STATE);
+		return tpm2_startup(dev, true, TPM2_SU_STATE);
 	else
 		return -ENOSYS;
 }
-- 
2.25.1