coreboot-kgpe-d16/payloads/libpayload/arch
Aaron Durbin 152e5a03a1 libpayload: honor TSC information under CONFIG_LP_TIMER_RDTSC
When CONFIG_LP_TIMER_RDTSC is enabled honor the TSC information
exported in the coreboot tables as the cpu_khz frequency. That
allows get_cpu_speed() not to be called which currently relies
on the 8254 PIT. As certain x86 platforms allow that device
to be optional or turned off for power saving reasons, allow
a path where get_cpu_speed() is no longer called. Additionally,
this approach also allows the libpayload to not duplicate logic
that already exists in coreboot.

BUG=chrome-os-partner:50214
BRANCH=glados
TEST=Confirmed in payload TSC frequency is honored instead of
     using get_cpu_speed().

Change-Id: Ib8993afdfb49065d43de705d6dbbdb9174b6f2c4
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/13671
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Andrey Petrov <andrey.petrov@intel.com>
2016-02-19 19:50:25 +01:00
..
arm tree: drop last paragraph of GPL copyright header 2015-10-31 21:37:39 +01:00
arm64 tree: drop last paragraph of GPL copyright header 2015-10-31 21:37:39 +01:00
mips tree: drop last paragraph of GPL copyright header 2015-10-31 21:37:39 +01:00
x86 libpayload: honor TSC information under CONFIG_LP_TIMER_RDTSC 2016-02-19 19:50:25 +01:00