cpu/x86/tsc: prepare for CAR_GLOBAL in delay_tsc.c

The current code in delay_tsc.c uses globals and is heavily
guarded by a lot of preprocessor macros.  In order to remove
__PRE_RAM__ constraints one needs to use CAR_GLOBAL for the
global variables.  Therefore, abstract away direct access to
the globals such that CAR_GLOBAL can be easily employed.

Change-Id: I3350d1a762120476926c8d9f5f5a7aba138daf5f
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/14300
Tested-by: build bot (Jenkins)
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Andrey Petrov <andrey.petrov@intel.com>
1 file changed