This change adds utility functions which allow to read any GPIO pin,
as well as a vector of GPIO pin values.
As presented, these functions will be available to Sandy Bridge and
Ivy Bridge systems only.
There is no error checking: trying to read GPIO pin number which
exceeds actual number of pins will return zero, trying to read GPIO
which is not actually configured as such will return unpredictable
value.
When reading a GPIO pin vector, the pin numbers are passed in an
array, terminated by -1. For instance, to read GPIO pins 4, 2, 15 as a
three bit number GPIO4 * 4 + GPIO2 * 2 + GPIO15 * 1, one should pass
pointer to array of {4, 2, 15, -1}.
Change-Id: I042c12dbcb3c46d14ed864a48fc37d54355ced7d
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: http://review.coreboot.org/1049
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
