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>

5 files changed, 36 insertions, 65 deletions

diff --git a/src/cpu/intel/haswell/Kconfig b/src/cpu/intel/haswell/Kconfig
index 13861f9..152059f 100644
--- a/src/cpu/intel/haswell/Kconfig
+++ b/src/cpu/intel/haswell/Kconfig
@@ -8,7 +8,8 @@ config CPU_SPECIFIC_OPTIONS
 	def_bool y
 	select SMP
 	select SSE2
-	select UDELAY_LAPIC
+	select UDELAY_TSC
+	select TSC_CONSTANT_RATE
 	select SMM_TSEG
 	select SMM_MODULES
 	select RELOCATABLE_MODULES
diff --git a/src/cpu/intel/haswell/Makefile.inc b/src/cpu/intel/haswell/Makefile.inc
index 90ffd66..60c061d 100644
--- a/src/cpu/intel/haswell/Makefile.inc
+++ b/src/cpu/intel/haswell/Makefile.inc
@@ -1,7 +1,9 @@
 ramstage-y += haswell_init.c
 subdirs-y += ../../x86/name
 ramstage-y += mp_init.c
+ramstage-y += tsc_freq.c
 romstage-y += romstage.c
+romstage-y += tsc_freq.c
 
 ramstage-$(CONFIG_GENERATE_ACPI_TABLES) += acpi.c
 ramstage-$(CONFIG_HAVE_SMI_HANDLER) += smmrelocate.c
@@ -10,6 +12,7 @@ ramstage-$(CONFIG_MONOTONIC_TIMER_MSR) += monotonic_timer.c
 cpu_microcode-$(CONFIG_CPU_MICROCODE_CBFS_GENERATE)  += microcode_blob.c
 
 smm-$(CONFIG_HAVE_SMI_HANDLER) += finalize.c
+smm-$(CONFIG_HAVE_SMI_HANDLER) += tsc_freq.c
 
 cpu_incs += $(src)/cpu/intel/haswell/cache_as_ram.inc
 
diff --git a/src/cpu/intel/haswell/tsc_freq.c b/src/cpu/intel/haswell/tsc_freq.c
new file mode 100644
index 0000000..0a78053
--- /dev/null
+++ b/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);
+}
diff --git a/src/northbridge/intel/haswell/Makefile.inc b/src/northbridge/intel/haswell/Makefile.inc
index 896360d..b2ac85e 100644
--- a/src/northbridge/intel/haswell/Makefile.inc
+++ b/src/northbridge/intel/haswell/Makefile.inc
@@ -29,7 +29,6 @@ romstage-y += early_init.c
 romstage-y += report_platform.c
 romstage-y += ../../../arch/x86/lib/walkcbfs.S
 
-smm-$(CONFIG_HAVE_SMI_HANDLER) += udelay.c
 smm-$(CONFIG_HAVE_SMI_HANDLER) += finalize.c
 
 # We don't ship that, but booting without it is bound to fail
diff --git a/src/northbridge/intel/haswell/udelay.c b/src/northbridge/intel/haswell/udelay.c
deleted file mode 100644
index f5d541e..0000000
--- a/src/northbridge/intel/haswell/udelay.c
+++ /dev/null
@@ -1,63 +0,0 @@
-/*
- * This file is part of the coreboot project.
- *
- * Copyright (C) 2007-2008 coresystems GmbH
- *
- * 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 <delay.h>
-#include <stdint.h>
-#include <cpu/x86/tsc.h>
-#include <cpu/x86/msr.h>
-#include "cpu/intel/haswell/haswell.h"
-
-/* Simple 32- to 64-bit multiplication. Uses 16-bit words to avoid overflow. */
-static inline void multiply_to_tsc(tsc_t *const tsc, const u32 a, const u32 b)
-{
-	tsc->lo = (a & 0xffff) * (b & 0xffff);
-	tsc->hi = ((tsc->lo >> 16)
-		+ ((a & 0xffff) * (b >> 16))
-		+ ((b & 0xffff) * (a >> 16)));
-	tsc->lo = ((tsc->hi & 0xffff) << 16) | (tsc->lo & 0xffff);
-	tsc->hi = ((a >> 16) * (b >> 16)) + (tsc->hi >> 16);
-}
-
-void udelay(u32 us)
-{
-	u32 dword;
-	tsc_t tsc, tsc1, tscd;
-	msr_t msr;
-	u32 divisor;
-	u32 d;			/* ticks per us */
-
-	msr = rdmsr(MSR_PLATFORM_INFO);
-	divisor = (msr.lo >> 8) & 0xff;
-
-	d = HASWELL_BCLK * divisor;
-	multiply_to_tsc(&tscd, us, d);
-
-	tsc1 = rdtsc();
-	dword = tsc1.lo + tscd.lo;
-	if ((dword < tsc1.lo) || (dword < tscd.lo)) {
-		tsc1.hi++;
-	}
-	tsc1.lo = dword;
-	tsc1.hi += tscd.hi;
-
-	do {
-		tsc = rdtsc();
-	} while ((tsc.hi < tsc1.hi)
-		 || ((tsc.hi == tsc1.hi) && (tsc.lo <= tsc1.lo)));
-}