Do the results of the tests confirm the absence of AHCI?
user @ Brooklyn: ~ $ dmesg | grep -i ahci
user @ Brooklyn: ~ $ dmesg | grep -i scsi
[ 0.128381] Initialized SCSI subsystem
[ 0.674506] Version 0.4 of the generic SCSI driver (bsg) of the block layer is loaded (249 main)
[ 0.856764] scsi host0: ata_piix
[ 0.856940] scsi host1: ata_piix
[ 1.012698] scsi host2: ata_piix
[ 1.012877] scsi host3: ata_piix
[ 2.436846] scsi 0: 0: 0: 0: Shortcut ATA ADATA SU655 1b10 PQ: 0 ANSI: 5
[ 2.437197] sd 0: 0: 0: 0: attached scsi generic sg0 type 0
[ 2.439191] sd 0: 0: 0: 0: [sda] Enclosed SCSI disk
[ 2.462147] scsi 1: 0: 0: 0: CD-ROM PLDS DVD-ROM DH-16D6S BD11 PQ: 0 ANSI: 5
[ 2.522761] sr 1: 0: 0: 0: [sr0] scsi3-mmc unit: 48x / 48x cd / rw xa / form2 cdda tray
[ 2.522960] sr 1: 0: 0: 0: scsi CD-ROM attached sr0
[ 2.523133] sr 1: 0: 0: 0: attached scsi generic sg1 type 5