cr50: add TPM vendor-specific commands to support EC-EFS2

Based on the design in go/ec-efs2, this patch adds two TPM
vendor-specific commands:
- VENDOR_CC_GET_BOOT_MODE
- VENDOR_CC_RESET_EC

BUG=b:141578322
BRANCH=cr50
TEST=tested with EC-EFS supporting EC/AP firmware.
With CR50 dev image, tested with gsctool on Octopus and Helios
by sending each of new vendor commands.
Checked flash_ec working on Scarlet in bitbang mode.

Change-Id: Ia8f38a7b9cc45b172a1a1ef7e216034e520b79c7
Signed-off-by: Namyoon Woo <namyoon@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1956409
Reviewed-by: Mary Ruthven <mruthven@chromium.org>

3 files changed, 49 insertions, 0 deletions

diff --git a/board/cr50/ec_efs.c b/board/cr50/ec_efs.c
index 677fb7d7f9..d7919e105c 100644
--- a/board/cr50/ec_efs.c
+++ b/board/cr50/ec_efs.c
@@ -9,6 +9,7 @@
 #include "ec_comm.h"
 #include "crc8.h"
 #include "ec_commands.h"
+#include "extension.h"
 #include "hooks.h"
 #include "registers.h"
 #include "system.h"
@@ -115,6 +116,48 @@ static void ec_efs_init_(void)
 }
 DECLARE_HOOK(HOOK_INIT, ec_efs_init_, HOOK_PRIO_DEFAULT);
 
+/**
+ * TPM vendor command handler to respond with EC Boot Mode.
+ *
+ * @return VENDOR_RC_SUCCESS
+ *
+ */
+static enum vendor_cmd_rc vc_get_boot_mode_(struct vendor_cmd_params *p)
+{
+	uint8_t *buffer;
+
+	if (!board_has_ec_cr50_comm_support())
+		return VENDOR_RC_NO_SUCH_SUBCOMMAND;
+
+	buffer = (uint8_t *)p->buffer;
+	buffer[0] = (uint8_t)ec_efs_ctx.boot_mode;
+
+	p->out_size = 1;
+
+	return VENDOR_RC_SUCCESS;
+}
+DECLARE_VENDOR_COMMAND_P(VENDOR_CC_GET_BOOT_MODE, vc_get_boot_mode_);
+
+/**
+ * TPM vendor command handler to reset EC.
+ *
+ * @return VEDOR_RC_SUCCESS
+ */
+static enum vendor_cmd_rc vc_reset_ec_(struct vendor_cmd_params *p)
+{
+	if (!board_has_ec_cr50_comm_support())
+		return VENDOR_RC_NO_SUCH_SUBCOMMAND;
+
+	/*
+	 * Let's reset EC a little later so that CR50 can send a TPM command
+	 * to AP.
+	 */
+	board_reboot_ec_deferred(50 * MSEC);
+
+	return VENDOR_RC_SUCCESS;
+}
+DECLARE_VENDOR_COMMAND_P(VENDOR_CC_RESET_EC, vc_reset_ec_);
+
 void ec_efs_reset(void)
 {
 	set_boot_mode_(EC_EFS_BOOT_MODE_NORMAL);
diff --git a/common/extension.c b/common/extension.c
index d2a26a6cd2..5a8daf6210 100644
--- a/common/extension.c
+++ b/common/extension.c
@@ -34,10 +34,12 @@ uint32_t extension_route_command(struct vendor_cmd_params *p)
 		case VENDOR_CC_SN_SET_HASH:
 		case VENDOR_CC_SN_INC_RMA:
 		case VENDOR_CC_ENDORSEMENT_SEED:
+		case VENDOR_CC_RESET_EC:
 #endif /* defined(CR50_DEV) */
 		case EXTENSION_POST_RESET: /* Always need to reset. */
 		case VENDOR_CC_CCD:
 		case VENDOR_CC_GET_BOARD_ID:
+		case VENDOR_CC_GET_BOOT_MODE:
 		case VENDOR_CC_RMA_CHALLENGE_RESPONSE:
 		case VENDOR_CC_SPI_HASH:   /* Requires physical presence. */
 		case VENDOR_CC_TURN_UPDATE_ON:
diff --git a/include/tpm_vendor_cmds.h b/include/tpm_vendor_cmds.h
index 5afd1fc84b..9f37e1a33c 100644
--- a/include/tpm_vendor_cmds.h
+++ b/include/tpm_vendor_cmds.h
@@ -143,6 +143,10 @@ enum vendor_cmd_cc {
 
 	VENDOR_CC_TRNG_TEST = 51,
 
+	/* EC EFS(Early Firmware Selection) commands */
+	VENDOR_CC_GET_BOOT_MODE = 52,
+	VENDOR_CC_RESET_EC = 53,
+
 	LAST_VENDOR_COMMAND = 65535,
 };