anchor.diff:    ;; LBA bit.
     (setf (ahci-fis ahci port +sata-register-device+) +ata-lba+))
   
  -(defun ahci-setup-buffer (ahci port buffer length write)
  +(defun ahci-setup-buffer (ahci port buffer length write atapi)
     "Configure the DMA buffer for this command."
     (let* ((ct (ahci-port-command-table (ahci-port ahci port)))
            (cl (ahci-port-command-list (ahci-port ahci port))))
  
positive.code:   received-fis
    command-table
    (irq-latch (make-latch "AHCI Port IRQ Notifier"))
    lba48-capable
    sector-size
    sector-count)
  
negative.code:       (setf (ldb (byte 1 +ahci-PxCMD-ST+) cmd) 1)
        (setf (ahci-port-register ahci port +ahci-register-PxCMD+) cmd))
      ;; Flush PxSERR.
      (setf (ahci-port-register ahci port +ahci-register-PxSERR+) #xFFFFFFFF)
      ;; Clear any outstanding interrupts on this port.
      (setf (ahci-port-register ahci port +ahci-register-PxIS+)
            (ahci-port-register ahci port +ahci-register-PxIS+))
  