Hi  Michael,
I am pulling-down the interrupt output from CPLD to blackfin. It seems you are 
connecting interrupt input from IDE to CPLD? Is it? Then I will make a try.
Thanks
Barry

-----Original Message-----
From: Hennerich, Michael 
Sent: Tuesday, July 21, 2009 4:53 PM
To: Song, Barry; 'Mike Frysinger'
Cc: '[email protected]'; '[email protected]'
Subject: RE: [Linux-kernel-commits] [6960] trunk/drivers/ata/libata-core.c: 1.

Hi Barry,

I don't understand.
Why do you think CPLD Interrupt Output Tristate (Blackfin GPIO INT) would help 
here?
The GPIO interrupt would be floating, when not driven active!
And I'm not aware of dedicated Pull/Ups/Downs on the STAMP board itself.

Did you add the resistor to the IDE_INTRQ on the IDE connector?
For me this workaround works perfectly.
See attached picture.

For the CF-Card slot this won't work - since when used in TRUE IDE MODE we need 
a Pull Down - and otherwise a Pull Up.

Answering your question -
The CPLD logic schematic sheets are also available on GFORGE.

The Logic Relationship between
IDE_INTRQ and BFIN_GPIO2 (PF5) is simple 

IDE_INTRQ = BFIN_GPIO2 


-Michael



________________________________________
From: Song, Barry
Sent: Tuesday, July 21, 2009 9:22 AM
To: Hennerich, Michael; Mike Frysinger
Cc: [email protected]; [email protected]
Subject: RE: [Linux-kernel-commits] [6960] trunk/drivers/ata/libata-core.c: 1.

Hi Michael,
What's the logic relationship between the CF/ATA signals and signals to 
blackfin you set in the CPLD? Even after we connect a 1000Ohm res to ground, 
the interrupt output to blackfin is still high. It seems the CPLD is outputing 
high but not keep tristate in default status. So we have to keep the 
probe-polling patch until the CPLD logic is fixed.
Thanks
Barry

-----Original Message-----
From: Hennerich, Michael [mailto:[email protected]]
Sent: Friday, July 10, 2009 11:18 PM
To: Mike Frysinger
Cc: [email protected]; [email protected]
Subject: RE: [Linux-kernel-commits] [6960] trunk/drivers/ata/libata-core.c: 1.


>it sounds like we just have to pop off a resistor ?

Well not that easy - I used a 0603 type 10k Resistor Pack including 4 resistors.

One trick could be to leave the PULL-Ups as is and add a stronger Pull-Down to 
the INTRQ - lets say something between 500 Ohm and 1kOhm .

-Michael

>-----Original Message-----
>From: Mike Frysinger [mailto:[email protected]]
>Sent: Friday, July 10, 2009 5:07 PM
>To: Hennerich, Michael
>Cc: [email protected];
[email protected]
>Subject: Re: [Linux-kernel-commits] [6960]
trunk/drivers/ata/libata-core.c: 1.
>
>On Fri, Jul 10, 2009 at 11:00, Hennerich, Michael wrote:
>> I think this issue is caused by a Pull-Up resistor on the INTRQ line
on
>> the CF-IDE-NAND Card.
>>
>> Read this:
>> http://www.mail-archive.com/[email protected]/msg00418.html
>>
>> On the CF Card socket we also have that pull-up - but there we had no 
>> choice since in PC-Card IO mode the Interrupt is asserted Low. So
this
>> was a tradeoff, and at the time doing the card - it worked without 
>> errors.
>>
>> The problem here is that the INTRQ signal output line has a high 
>> impedance when no devices are selected or interruption is disabled.
>>
>> Like you noticed, recent Linux libata assumes the INTRQ staying
inactive
>> the time between the IRQ is requested and the device is configured.
>>
>> If this fix isn't acceptable to mainline we should revert - and fix
the
>> HW.
>
>can the simple instructions of how to patch the card be added to the 
>wiki ?  it sounds like we just have to pop off a resistor ?
>-mike

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