baytrail: add vboot ramstage verification

Add suport for verifying the ramstage with vboot
during romstage execution. Along with this support
select CACHE_RELOCATED_RAMSTAGE_OUTSIDE_CBMEM to
cache the relocated ramstage 1MiB below the
top end of the TSEG region.

BUG=chrome-os-partner:23249
BRANCH=None
TEST=Built and booted with CONFIG_VBOOT_VERIFY_FIRMWARE=y
     selected.

Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Change-Id: I355f62469bdcca62b0a4468100effab0342dc8fc
Reviewed-on: https://chromium-review.googlesource.com/172712
Reviewed-by: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-on: http://review.coreboot.org/4880
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
diff --git a/src/soc/intel/baytrail/romstage/romstage.c b/src/soc/intel/baytrail/romstage/romstage.c
index 4228615..4d74b53 100644
--- a/src/soc/intel/baytrail/romstage/romstage.c
+++ b/src/soc/intel/baytrail/romstage/romstage.c
@@ -25,12 +25,15 @@
 #include <console/console.h>
 #include <cbmem.h>
 #include <cpu/x86/mtrr.h>
+#include <ramstage_cache.h>
 #include <romstage_handoff.h>
 #include <timestamp.h>
+#include <vendorcode/google/chromeos/chromeos.h>
 #include <baytrail/gpio.h>
 #include <baytrail/iomap.h>
 #include <baytrail/lpc.h>
 #include <baytrail/pci_devs.h>
+#include <baytrail/reset.h>
 #include <baytrail/romstage.h>
 
 static inline uint64_t timestamp_get(void)
@@ -169,6 +172,9 @@
 
 	timestamp_add_now(TS_END_ROMSTAGE);
 
+	/* Run vboot verification if configured. */
+	vboot_verify_firmware(romstage_handoff_find_or_add());
+
 	/* Load the ramstage. */
 	copy_and_run();
 	while (1);
@@ -270,3 +276,25 @@
 
 	return slot;
 }
+
+struct ramstage_cache *ramstage_cache_location(long *size)
+{
+	char *smm_base;
+	/* 1MiB cache size */
+	const long cache_size = (1 << 20);
+
+	/* Ramstage cache lives in TSEG region which is the definition of
+	 * cbmem_top(). */
+	smm_base = cbmem_top();
+	*size = cache_size;
+	return (void *)&smm_base[CONFIG_SMM_TSEG_SIZE - cache_size];
+}
+
+void ramstage_cache_invalid(struct ramstage_cache *cache)
+{
+#if CONFIG_RESET_ON_INVALID_RAMSTAGE_CACHE
+	/* Perform cold reset on invalid ramstage cache. */
+	cold_reset();
+#endif
+}
+