REF_CLK_MASK      187 drivers/gpu/drm/bridge/analogix/analogix_dp_reg.h #define REF_CLK_MASK				(0x1 << 0)
REF_CLK_MASK     1341 drivers/gpu/drm/gma500/psb_intel_reg.h #define	REF_CLK_MASK		(0x3 << 13)