Re: Compact flash disk and slave drives in 2.4.2

[Padraig Brady]

How do you activate the walk around you describe
to allow the detection of the slave? hda=ataflash?
Is this sort of stuff documented anywhere?

For those interested you also mention it here:
http://lists.sourceforge.net/archives//linux-usb-devel/2000-August/000929.html

This describes the other combination that causes
a problem where you have a normal disk as master
and the CF as slave:
http://boudicca.tux.org/hypermail/linux-kernel/2000week25/0973.html

Again the problem unresolved:
http://boudicca.tux.org/hypermail/linux-kernel/2000week26/0174.html

cheers,
Padraig.

Andre Hedrick wrote:

> Because 'real' ATA devices use a signature map the detects presense of
> master slave during execute diagnostics.  This is done in the BIOS.
> CFA does no report this correctly and waiting for a 31 second time out is
> not acceptable.  If you have a complain take it to CFA commitee and have
> them fix it.
> 
> I put in a walk around for having 2 CFA's to allow detection.
> This will work also if you call it for a CFA+Disk pair.
> 
> On Tue, 27 Mar 2001, Padraig Brady wrote:
> 
>> OK the following assumes CF never have slaves which is just wrong.
>> The CF should be logically treated as an IDE harddisk. So the fix is
>> probably have a kernel parameter that causes the following check to
>> be skipped?
> 
> Logically treated, is true, but again CFA does not follow the rules of
> what the ATA committee gives them, and I refuse to break rules as the
> standard model.  Rule breaking are exceptions.
> 
> Also show me a case where a laptop will do master/slave in CFA.
> 
>> /*
>>    * Prevent long system lockup probing later for non-existant
>>    * slave drive if the hwif is actually a flash memory card of some 
>> variety:
>>    */
>>   if (drive_is_flashcard(drive)) {
>>           ide_drive_t *mate = &HWIF(drive)->drives[1^drive->select.b.unit];
>>           if (!mate->ata_flash) {
>>                 mate->present = 0;
>>                 ide_drive_t *mate = 
>> &HWIF(drive)->drives[1^drive->select.b.unit]
>>                 mate->noprobe = 1;
>>           }
>>   }
>> 
>> But do we need this check? Is it just for speed. If you have an "ordinary"
>> harddrive as master with no slave, will the check for slave cause the same
>> "long system lockup", and if not, why.
>> 
>> Padraig.
>> 
>> Andre Hedrick wrote:
>> 
>> 
>>> Because in laptops, the primary use of CFA.
>>> Laptops using CFA do not have slaves.
>> 
> 
> Andre Hedrick
> Linux ATA Development
> ASL Kernel Development
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