tpm: add TPM2_Startup command support

Add support for the TPM2_Startup command.

Change the command file and the help accordingly.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c
index 35dee03..1a81177 100644
--- a/lib/tpm-v2.c
+++ b/lib/tpm-v2.c
@@ -9,3 +9,24 @@
 #include <tpm-common.h>
 #include <tpm-v2.h>
 #include "tpm-utils.h"
+
+u32 tpm2_startup(enum tpm2_startup_types mode)
+{
+	const u8 command_v2[12] = {
+		tpm_u16(TPM2_ST_NO_SESSIONS),
+		tpm_u32(12),
+		tpm_u32(TPM2_CC_STARTUP),
+		tpm_u16(mode),
+	};
+	int ret;
+
+	/*
+	 * Note TPM2_Startup command will return RC_SUCCESS the first time,
+	 * but will return RC_INITIALIZE otherwise.
+	 */
+	ret = tpm_sendrecv_command(command_v2, NULL, NULL);
+	if (ret && ret != TPM2_RC_INITIALIZE)
+		return ret;
+
+	return 0;
+}