You need to show us the full dmesg. We cannot see which controller is
applying limits here.
You need to look at the controller's maximum, as that controls the drive
maximum (pasted from my personal workstation):
scsi0 : ahci
scsi1 : ahci
scsi2 : ahci
scsi3 : ahci
ata1: SATA max UDMA/133 abar m1024@0x90404000 port 0x90404100 irq 507
ata2: SATA max UDMA/133 abar m1024@0x90404000 port 0x90404180 irq 507
ata3: SATA max UDMA/133 abar m1024@0x90404000 port 0x90404200 irq 507
ata4: SATA max UDMA/133 abar m1024@0x90404000 port 0x90404280 irq 507
scsi4 : sata_sil
scsi5 : sata_sil
scsi6 : sata_sil
scsi7 : sata_sil
ata5: SATA max UDMA/100 mmio m1024@0x9000c800 tf 0x9000c880 irq 17
ata6: SATA max UDMA/100 mmio m1024@0x9000c800 tf 0x9000c8c0 irq 17
ata7: SATA max UDMA/100 mmio m1024@0x9000c800 tf 0x9000ca80 irq 17
ata8: SATA max UDMA/100 mmio m1024@0x9000c800 tf 0x9000cac0 irq 17
See the UDMA difference?
Jeff
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