baytrail: romstage: Add config option to enable RMT

Add config option to enable RMT in the MRC.

BUG=chrome-os-partner:21807
TEST=Manual. Build w/ "USE=rmt", verify RMT print seen on FW console.
Build w/o USE flag, verify no RMT print.
BRANCH=None.
CQ-DEPEND=CL:*148655

Change-Id: Ibd3da87317a3359e797d9b43bc437e7227a85048
Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/178095
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/4982
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>

src/soc/intel/baytrail/Kconfig

@@ -80,6 +80,10 @@ config MRC_BIN_ADDRESS
 	hex
 	default 0xfffa0000
 
+config MRC_RMT
+	bool "Enable MRC RMT training + debug prints"
+	default n
+
 config CACHE_MRC_SETTINGS
 	bool "Save cached MRC settings"
 	default n

src/soc/intel/baytrail/baytrail/mrc_wrapper.h

@@ -28,7 +28,7 @@
 #ifndef _MRC_WRAPPER_H_
 #define _MRC_WRAPPER_H_
 
-#define MRC_PARAMS_VER  1
+#define MRC_PARAMS_VER  2
 
 #define NUM_CHANNELS 2
 
@@ -78,6 +78,7 @@ struct mrc_params {
 	const void *saved_data;
 
 	int txe_size_mb; /* TXE memory size in megabytes. */
+	int rmt_enabled; /* Enable RMT training + prints. */
 
 	/* Outputs */
 	void *txe_base_address;

src/soc/intel/baytrail/romstage/raminit.c

@@ -118,7 +118,9 @@ void raminit(struct mrc_params *mp, int prev_sleep_state)
 	mp->version = MRC_PARAMS_VER;
 	mp->console_out = &send_to_console;
 	mp->prev_sleep_state = prev_sleep_state;
-
+#if CONFIG_MRC_RMT
+	mp->rmt_enabled = 1;
+#endif
 	if (recovery_mode_enabled()) {
 		printk(BIOS_DEBUG, "Recovery mode: not using MRC cache.\n");
 	} else if (!mrc_cache_get_current(&cache)) {