Re: libata-dev#upstream pdc_adma fails IDENTIFY w/ AC_ERR_HSM

[Tejun Heo <htejun@gmail.com>]

Mark Lord wrote:
> Jeff Garzik wrote:
>> Tejun Heo wrote:
>>> [adma_intr_mmio      ] ata1: protocol 2 (dev_stat 0x58)
>>> [ata_port_flush_task ] ENTER
>>> [ata_port_flush_task ] flush #1
>>> ata1: ata_port_flush_task: flush #2
>>> ata1: ata_port_flush_task: EXIT
>>> ata1.00: failed to IDENTIFY (I/O error, err_mask=0x2)
>>
>>
>> AC_ERR_HSM comes from the call to ac_err_mask().  Given a Status of 
>> 0x58, it would appear that DRQ is asserted.
>>
>> So if I had to guess, I would say that the above interrupt is the 
>> DRQ-is-asserted indication, which would imply perhaps that this driver 
>> should not bother with PIO polling.
> 
> I think this illustrates just how few people (Tejun) actually have
> these chips and use them with Linux.  :)

Thanks to you. :-)  Pretty cards though.

> I don't have a system to test this with today (long story),
> but I'm trying to piece one together for later.
> 
> Is this "IDENTIFY using IRQs rather than polling" a newish feature?
> Because I just don't see how it could work with the the existing
> adma_intr_mmio routine --> that code is only correct for non-data
> commands, and IDENTIFY definitely has data.

IDENTIFY w/ IRQs came with Albert Lee's irq-pio which was merged into 
mainline together with new EH.

-- 
tejun