[coreboot] [PATCH 2/4] Enable TSC calibration with timer2 by default.

Kevin O'Connor kevin at koconnor.net
Tue Sep 7 01:23:56 CEST 2010

Enable TSC_X86RDTSC_CALIBRATE_WITH_TIMER2 by default.  Without this
set, almost all boards use the inb(0x80) method.  Unfortunately, that
method takes over a second to calibrate, and it's results are not as

There is a chance that some boards may not work well with the timer2
method.  This is likely rare, because both libpayload and seabios use
the timer2 method unconditionally and there has not been reports of an
issue.  Should a board not support the more accurate timer2 mechanism,
it will need to be updated to actively disable it.

Signed-off-by: Kevin O'Connor <kevin at koconnor.net>
 src/cpu/x86/Kconfig |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/src/cpu/x86/Kconfig b/src/cpu/x86/Kconfig
index 325991e..8cd999e 100644
--- a/src/cpu/x86/Kconfig
+++ b/src/cpu/x86/Kconfig
@@ -21,7 +21,7 @@ config UDELAY_TSC
-	default n
+	default y
 config XIP_ROM_BASE

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