Am I using IDE or AHCI?

dmesg | grep -i ahci

[    1.971970] ahci 0000:00:1f.2: version 3.0
[    1.972034] ahci 0000:00:1f.2: irq 41 for MSI/MSI-X
[    1.972071] ahci: SSS flag set, parallel bus scan disabled
[    1.986971] ahci 0000:00:1f.2: AHCI 0001.0300 32 slots 6 ports 6 Gbps 0x7 impl SATA mode
[    1.986974] ahci 0000:00:1f.2: flags: 64bit ncq sntf stag pm led clo pio slum part ems apst 
[    1.986980] ahci 0000:00:1f.2: setting latency timer to 64
[    2.003333] scsi0 : ahci
[    2.003408] scsi1 : ahci
[    2.003473] scsi2 : ahci
[    2.003536] scsi3 : ahci
[    2.003596] scsi4 : ahci
[    2.003658] scsi5 : ahci

You can also look at this place by the command:

lspci -v

00:1f.2 SATA controller: ... SATA Controller [AHCI mode] (rev 04) (prog-if 01 [AHCI 1.0])
    Subsystem: blabla...
    ...
    Kernel driver in use: ahci
    Kernel modules: ahci