Re: Hotswap IDE

[Bill Davidsen <davidsen@tmr.com>]

Johannes Stezenbach wrote:
> Mike Black wrote:
> 
>>I use a removable IDE chassis to allow me to mirror my primary drive for offsite storage.
>>I'd like to hotswap the IDE but can't seem to get the drive to allow DMA access after restarting it.
>>A reboot is necessary for DMA access.
>>I'm using idectl from hdparm-5.4 which generates the following hdparm commands:
>>/sbin/hdparm -U 1 /dev/hda
>>/sbin/hdparm -R 0x170 0 0 /dev/hda
> 
> 
> I haven't tried myself, but Alan Cox did:
> 
> Linux 2.4.22-rc2-ac3
>  o       Finish off the core IDE hotplug support         (me)
>          | If your hardware supports it you can now
>          | hdparm -b0 /dev/hdc  change drive hdparm -b1 /dev/hdc
> 
> Maybe that works better than -U/-R ?

I suspect that both might not be a bad thing, set the bus down and 
unregister, then set the bus up and register. Order may be important!

Let me know if you try this, I have been contemplating using a hotswap 
drive for data transfer.

-- 
bill davidsen <davidsen@tmr.com>
   CTO TMR Associates, Inc
   Doing interesting things with small computers since 1979