ucMaxDownSpread  4210 drivers/gpu/drm/amd/include/atombios.h   UCHAR   ucMaxDownSpread;         //Bit0 = 0: No Down spread; Bit0 = 1: 0.5% (Subject to change according to DP spec)
ucMaxDownSpread  3729 drivers/gpu/drm/radeon/atombios.h   UCHAR   ucMaxDownSpread;         //Bit0 = 0: No Down spread; Bit0 = 1: 0.5% (Subject to change according to DP spec)