soc/intel/apollolake: use CAR code coherency for all CAR stages

The flush L1D to L2 operation was only being used when loading
romstage from bootblock. However, when the FSP-M component is
loaded no code coherency actions are taken. I suspect this is
because the FSP-M component is larger than the 24KiB L1D and
the entry point is early in the image. Thus, when loading
the FSP-M component the earlier part of the image is flushed
out to L2 in the process of loading the latter part of the
component. Also, once verstage is introduced the same
code coherency actions need to be taken as well. Therefore,
position the apollolake code to handle all these cases.

Change-Id: Ie71764f1b420a6072c4f149ad3e37278b6cb70e1
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/14210
Tested-by: build bot (Jenkins)
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Andrey Petrov <andrey.petrov@intel.com>
diff --git a/src/soc/intel/apollolake/car.c b/src/soc/intel/apollolake/car.c
new file mode 100644
index 0000000..7646865
--- /dev/null
+++ b/src/soc/intel/apollolake/car.c
@@ -0,0 +1,33 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2016 Intel Corp.
+ * Copyright 2016 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <arch/cpu.h>
+#include <program_loading.h>
+#include <soc/cpu.h>
+
+/*
+ * This file supports the necessary hoops one needs to jump through since
+ * early FSP component and early stages are running from cache-as-ram.
+ */
+
+static void flush_l1d_to_l2(void)
+{
+	msr_t msr = rdmsr(MSR_POWER_MISC);
+	msr.lo |= (1 << 8);
+	wrmsr(MSR_POWER_MISC, msr);
+}
+
+void platform_prog_run(struct prog *prog)
+{
+	/* Flush L1D cache to L2 */
+	flush_l1d_to_l2();
+}