[coreboot-gerrit] Patch set updated for coreboot: sandybridge: provide monotonic timer function
Patrick Georgi (pgeorgi@google.com)
gerrit at coreboot.org
Mon Jul 6 21:48:29 CEST 2015
Patrick Georgi (pgeorgi at google.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/10813
-gerrit
commit 8d4b38e8b3c4b732046742331c3b92d418384193
Author: Patrick Georgi <pgeorgi at chromium.org>
Date: Mon Jul 6 20:50:33 2015 +0200
sandybridge: provide monotonic timer function
This fixes building the ELOG_GSMI feature by using the TSC as time source for
the flash drivers.
It's not the most precise clock, but should be good enough for the purpose.
Change-Id: I2d416c34268236228300a9e868628c35e22bf40c
Signed-off-by: Patrick Georgi <pgeorgi at chromium.org>
---
src/northbridge/intel/sandybridge/udelay.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/src/northbridge/intel/sandybridge/udelay.c b/src/northbridge/intel/sandybridge/udelay.c
index b150253..7c98380 100644
--- a/src/northbridge/intel/sandybridge/udelay.c
+++ b/src/northbridge/intel/sandybridge/udelay.c
@@ -53,3 +53,23 @@ void udelay(u32 us)
} while ((tsc.hi < tsc1.hi)
|| ((tsc.hi == tsc1.hi) && (tsc.lo < tsc1.lo)));
}
+
+#if CONFIG_LAPIC_MONOTONIC_TIMER && !defined(__PRE_RAM__)
+#include <timer.h>
+
+void timer_monotonic_get(struct mono_time *mt)
+{
+ tsc_t tsc;
+ msr_t msr;
+ u32 fsb = 100, divisor;
+ u32 d; /* ticks per us */
+
+ msr = rdmsr(0xce);
+ divisor = (msr.lo >> 8) & 0xff;
+ d = fsb * divisor; /* On Core/Core2 this is divided by 4 */
+
+ tsc = rdtsc();
+
+ mt->microseconds = (long)((((uint64_t)tsc.hi << 32) | tsc.lo) / d);
+}
+#endif
More information about the coreboot-gerrit
mailing list