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>

cmd/tpm-v2.c

@@ -11,9 +11,30 @@
 #include <tpm-v2.h>
 #include "tpm-user-utils.h"
 
+static int do_tpm2_startup(cmd_tbl_t *cmdtp, int flag, int argc,
+			   char * const argv[])
+{
+	enum tpm2_startup_types mode;
+
+	if (argc != 2)
+		return CMD_RET_USAGE;
+
+	if (!strcasecmp("TPM2_SU_CLEAR", argv[1])) {
+		mode = TPM2_SU_CLEAR;
+	} else if (!strcasecmp("TPM2_SU_STATE", argv[1])) {
+		mode = TPM2_SU_STATE;
+	} else {
+		printf("Couldn't recognize mode string: %s\n", argv[1]);
+		return CMD_RET_FAILURE;
+	}
+
+	return report_return_code(tpm2_startup(mode));
+}
+
 static cmd_tbl_t tpm2_commands[] = {
 	U_BOOT_CMD_MKENT(info, 0, 1, do_tpm_info, "", ""),
 	U_BOOT_CMD_MKENT(init, 0, 1, do_tpm_init, "", ""),
+	U_BOOT_CMD_MKENT(startup, 0, 1, do_tpm2_startup, "", ""),
 };
 
 cmd_tbl_t *get_tpm_commands(unsigned int *size)
@@ -30,4 +51,9 @@ U_BOOT_CMD(tpm, CONFIG_SYS_MAXARGS, 1, do_tpm, "Issue a TPMv2.x command",
 "    Show information about the TPM.\n"
 "init\n"
 "    Initialize the software stack. Always the first command to issue.\n"
+"startup <mode>\n"
+"    Issue a TPM2_Startup command.\n"
+"    <mode> is one of:\n"
+"        * TPM2_SU_CLEAR (reset state)\n"
+"        * TPM2_SU_STATE (preserved state)\n"
 );

include/tpm-v2.h

@@ -125,4 +125,13 @@ enum tpm2_algorithms {
 	TPM2_ALG_NULL		= 0x10,
 };
 
+/**
+ * Issue a TPM2_Startup command.
+ *
+ * @mode	TPM startup mode
+ *
+ * @return code of the operation
+ */
+u32 tpm2_startup(enum tpm2_startup_types mode);
+
 #endif /* __TPM_V2_H */

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;
+}