CP_RB1_CNTL
tmp = REG_SET_FIELD(0, CP_RB1_CNTL, RB_BUFSZ, rb_bufsz);
tmp = REG_SET_FIELD(tmp, CP_RB1_CNTL, RB_BLKSZ, rb_bufsz - 2);
tmp = REG_SET_FIELD(0, CP_RB1_CNTL, RB_BUFSZ, rb_bufsz);
tmp = REG_SET_FIELD(tmp, CP_RB1_CNTL, RB_BLKSZ, rb_bufsz - 2);
CP_RB1_CNTL,
WREG32(CP_RB1_CNTL, tmp);
WREG32(CP_RB1_CNTL, tmp | RB_RPTR_WR_ENA);
WREG32(CP_RB1_CNTL, tmp);