soc/intel/quark: Add monotonic timer support

Add the Kconfig value HAVE_MONOTONIC_TIMER and the routine to read the
TSC for the monotonic timer.  Simplify the routine to get the TSC
frequency.

TEST=Build and run on Galileo Gen2

Change-Id: I806fb864b01e39277bf2d6276254b0543930c2f6
Signed-off-by: Lee Leahy <leroy.p.leahy@intel.com>
Reviewed-on: https://review.coreboot.org/18002
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Martin Roth <martinroth@google.com>

2 files changed, 8 insertions, 9 deletions

diff --git a/src/soc/intel/quark/Kconfig b/src/soc/intel/quark/Kconfig
index c5efd4a2968b..8182caa51cbf 100644
--- a/src/soc/intel/quark/Kconfig
+++ b/src/soc/intel/quark/Kconfig
@@ -29,6 +29,7 @@ config CPU_SPECIFIC_OPTIONS
 	select BOOTBLOCK_SAVE_BIST_AND_TIMESTAMP
 	select C_ENVIRONMENT_BOOTBLOCK
 	select HAVE_HARD_RESET
+	select HAVE_MONOTONIC_TIMER
 	select NO_MMCONF_SUPPORT
 	select REG_SCRIPT
 	select RELOCATABLE_RAMSTAGE
diff --git a/src/soc/intel/quark/tsc_freq.c b/src/soc/intel/quark/tsc_freq.c
index eb8c46ecf271..e6d0369eff5c 100644
--- a/src/soc/intel/quark/tsc_freq.c
+++ b/src/soc/intel/quark/tsc_freq.c
@@ -17,20 +17,18 @@
 #include <stdint.h>
 #include <cpu/x86/msr.h>
 #include <cpu/x86/tsc.h>
+#include <timer.h>
 
-static unsigned long bus_freq_khz(void)
+unsigned long tsc_freq_mhz(void)
 {
 	/* CPU freq = 400 MHz */
-	return 400 * 1000;
+	return 400;
 }
 
-unsigned long tsc_freq_mhz(void)
+void timer_monotonic_get(struct mono_time *mt)
 {
-	/* assume ratio=1 */
-	unsigned bclk_khz = bus_freq_khz();
-
-	if (!bclk_khz)
-		return 0;
+	uint64_t tsc_value;
 
-	return (bclk_khz * 1) / 1000;
+	tsc_value = rdtscll();
+	mt->microseconds = tsc_value / tsc_freq_mhz();
 }