#define IS_GEN_IIE(hpriv) ((hpriv)->hp_flags & MV_HP_GEN_IIE)
 
 enum {
-       MV_DMA_BOUNDARY         = 0xffffffffU,
+       /* DMA boundary 0xffff is required by the s/g splitting
+        * we need on /length/ in mv_fill-sg().
+        */
+       MV_DMA_BOUNDARY         = 0xffffU,
 
        /* mask of register bits containing lower 32 bits
         * of EDMA request queue DMA address
        .queuecommand           = ata_scsi_queuecmd,
        .can_queue              = ATA_DEF_QUEUE,
        .this_id                = ATA_SHT_THIS_ID,
-       .sg_tablesize           = MV_MAX_SG_CT,
+       .sg_tablesize           = MV_MAX_SG_CT / 2,
        .cmd_per_lun            = ATA_SHT_CMD_PER_LUN,
        .emulated               = ATA_SHT_EMULATED,
        .use_clustering         = 1,
        .queuecommand           = ata_scsi_queuecmd,
        .can_queue              = ATA_DEF_QUEUE,
        .this_id                = ATA_SHT_THIS_ID,
-       .sg_tablesize           = MV_MAX_SG_CT,
+       .sg_tablesize           = MV_MAX_SG_CT / 2,
        .cmd_per_lun            = ATA_SHT_CMD_PER_LUN,
        .emulated               = ATA_SHT_EMULATED,
        .use_clustering         = 1,