MC_ARB_RFSH_RATE
arb_registers->mc_arb_rfsh_rate = RREG32(MC_ARB_RFSH_RATE);
WREG32_P(MC_ARB_RFSH_RATE, POWERMODE0(val), ~POWERMODE0_MASK);
WREG32_P(MC_ARB_RFSH_RATE, POWERMODE0(val), ~POWERMODE0_MASK);
arb_refresh_rate = RREG32(MC_ARB_RFSH_RATE) &
WREG32(MC_ARB_RFSH_RATE, arb_refresh_rate);
WREG32(MC_ARB_RFSH_RATE, arb_refresh_rate);