On Wednesday 27 June 2007, Sergei Shtylyov wrote: > >>>>Set Transfer Mode subcode of the Set Features command, you're always selecting > >>>>the flow control mode, i.e. using IORDY. So, the last condition in this if > > >> So, what actually would need fixing in *all* the drivers if one was aiming > >>at ATA-1 compatibility is *not* issuing that subcommand to such drives... > > > I was actually thinking about a different way of fixing this: > > > - remove 0x08 bit from XFER_PIO_[0,6] defines and add new XFER_PIO_IORDY > > define (<linux/ata.h>) > > Nah, that wouldn't match to the ATA definition of these values. > > > - check for speed == XFER_PIO_[0,6] in ide-lib.c::ide_config_drive_speed() > > It's in ide-iops.c. ;-) > > > and pmac.c::pmac_ide_do_setfeature(), add XFER_PIO_IORDY if needed > > And what, just pass the mode thru to the Set Features if there's no IORDY > support? That would be bogus since there are just *no* subcodes to set the > specific mode below 0x08 -- the only defined subcodes are 0x00 (set default > mode), and 0x01 (set default mode w/o IORDY). Thinko on my side. Damn, I should have re-check ATA specs before writing this. :) > I was thinking of checking if the drive really supports IORDY before > issuing a command to set PIO mode (and just skipping the command if there's no > IORDY -- well, maybe adding an extra check that the passed mode is acceptable > to the drive, i.e. <= its default one). Should be quite simple to do. Sounds fine. > > This should be done together with fixing these host drivers that don't > > handle IORDY properly. > > Erm, not necessarily... Hmm, yes. I'll just count on you with fixing all this IORDY stuff (as you have much more expertise in this field) and concentrate on other things. > >>>Oh yes, I keep forgetting about it - some nice FIXME comment > >>>in <linux/ata.h> would be of a great help. :-) > > >> Well, some drivers (like pdc202xx_*) don't do the IORDY thing right for > >>PIO modes < 3 as well... > > > Added to the existing IDE TODO at > > > http://kernel.org/pub/linux/kernel/people/bart/pata-2.6/TODO > > > Patches adding/removing items are welcomed. > > > Patches fixing actual issues are welcomed even more. > > Sigh, I'm trying to get some time (more like time slices :-) off to deal > with my own issues... Which reminds me about some HPT IDE patches... 8) Bart - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
