CH_XY_SRC
cmd[6] = FIELD_PREP(CH_XY_SRC, desc->xsize) | FIELD_PREP(CH_XY_DES, desc->xsize);
cmd[7] = FIELD_PREP(CH_XY_SRC, desc->xsizehi) | FIELD_PREP(CH_XY_DES, desc->xsizehi);
cmd[10] = FIELD_PREP(CH_XY_SRC, 1) | FIELD_PREP(CH_XY_DES, 1);