haswell: use tsc for udelay()

Instead of using the local apic timer for udelay() use the tsc.
That way SMM, romstage, and ramstage all use the same delay
functionality.

Change-Id: I024de5af01eb5de09318e13d0428ee98c132f594
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/3169
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/cpu/intel/haswell/tsc_freq.c

@@ -0,0 +1,31 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2013 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; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+#include <cpu/x86/msr.h>
+#include <cpu/x86/tsc.h>
+#include "cpu/intel/haswell/haswell.h"
+
+unsigned long tsc_freq_mhz(void)
+{
+	msr_t platform_info;
+
+	platform_info = rdmsr(MSR_PLATFORM_INFO);
+	return HASWELL_BCLK * ((platform_info.lo >> 8) & 0xff);
+}