Re: [PATCH] ide: motherboard-info based blacklist for ide-dma

[Sergei Shtylyov <sshtylyov@ru.mvista.com>]

Hello.

Dmitry Gryazin wrote:

>>>>>>>>>>True.  However it should be possible to handle it correctly by
>>>>>>>>>>adding
>>>>>>>>>>the
>>>>>>>>>>DMA quirk to the respective host drivers (seems to be
>>>>>>>>>>via82cxxx.c in
>>>>>>>>>>case of
>>>>>>>>>>IEI PCISA-C3/EDEN).

>>>>>>>>> Yeah, this seems a viable approach...

>>>>>>>>>>Kirill, could you please look into adding such quirk to via82cxxx
>>>>>>>>>>instead?

>>>>>>>>>>[ It seems the best place to add it would be via_init_one() as we
>>>>>>>>>>could just

>>>>>>>>> No, not really -- the issue is not at all as simple as this patch
>>>>>>>>>tried to present it. Looking at its "Quick Startup Reference"
>>>>>>>>>(http://f.ipc2u.ru/files/add/doc/496/M_PCISA-C800EV_ENG.pdf), the
>>>>>>>>>EPIC
>>>>>>>>>board has *two* normal IDE connectors in addition to the CF slot
>>>>>>>>>(connected to the secondary port -- and it seems possible that a
>>>>>>>>>hard
>>>>>>>>>drive can be connected to the same port as CF), so the right place
>>>>>>>>>seems to rather be in [mu]dma_filter() methods -- and the decision
>>>>>>>>>should be strictly based on the drive type indicating CF, i.e. by
>>>>>>>>>calling ata_id_is_cfa().

>>>>>I have tried my old Trancend 64Mb, RamStar 521Mb and NCP 64Mb cards.
>>>>>My old cards returned right id[ATA_ID_CONFIG] = 0x848A.

>>>>>But I have to use Kingston CF Card 1Gb 2008.
>>>>>ata_id_is_cfa() returns 0 for it and
>>>>>id[ATA_ID_MAJOR_VER]    = 0

    Ah, so it doesn't bother to report the ATA/PI support... haven't noticed 
that at first. Too many lists ot watch and things to do. :-]

>>>>>id[ATA_ID_CONFIG]        = 0x044A

>>>>   That seems non-standard CF as ATA specifies that it must have
>>>>0x848A there.

    No, it mustn't.
    What does it have in id[ATA_ID_COMMAND_SET_2]?

>>>>>I have only CF+ specification revision 2.0,  but I've found in wiki:

>>>>   Try googling for cfspc_41.pdf (and other versions), you'll be
>>>>surprised in a good way. ;-)

>>>>>(http://en.wikipedia.org/wiki/CompactFlash#CF.2B_specification_revisions)

>>>>>"... While the current revision 4.1 from 2004 works only in ATA mode,
>>>>>..."

>>>>>So I have reached an impasse. How to identify modern CF cards?

>>>>   Hm, I should consult the specs...

>>>   ATA/PI-7 rev. 4b has this in 4.10:

>>>Devices reporting the value 848Ah in IDENTIFY DEVICE data word 0 or
>>>devices having bit 2 of IDENTIFY DEVICE data word 83 set to one shall
>>>support the CFA feature Set. If the CFA feature set is implemented, all
>>>five commands shall be implemented.

>>>   Alan, looks like the libata's CF criterion needs to be enhanced.

>>    Oops, my bad -- I should've looked first. :-<
>>    Dmitry, just use the modern version of ata_id_is_cfa().

> Sergei, I use the latest kernel from git repository
> (http://www.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git), if 
> you are talking about this patch:
> 37014c64079748c47fd109ef2d91ecd785a8c764

    No, about this:

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=b352e57dc3bb5033996adaa67c2f69b795eddd39

    (Please in the future post the direct link to commit instead -- will save 
everybody's time.)

> Regards, Dmitry

MBR, Sergei