Messages in this thread | | | Date | Mon, 13 Feb 2006 21:21:31 +0100 | From | Bartlomiej Zolnierkiewicz <> | Subject | Re: RFC: Compact Flash True IDE Mode Driver |
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On 2/13/06, Kumar Gala <galak@kernel.crashing.org> wrote: > > On Feb 13, 2006, at 10:53 AM, Bartlomiej Zolnierkiewicz wrote: > > > On 2/13/06, Kumar Gala <galak@kernel.crashing.org> wrote: > > > >>>> +static void cfide_outsl(unsigned long port, void *addr, u32 count) > >>>> +{ > >>>> + panic("outsl unsupported"); > >>>> +} > >>> > >>> This will panic as soon as somebody tries to enable 32-bit I/O > >>> using hdparm. Please add ide_hwif_t.no_io_32bit flag and teach > >>> ide-disk.c:ide_disk_setup() about it (separate patch). > >> > >> I'm not sure I follow this, can you expand. > > > > Do "hdparm -c 2 /dev/hdx" first and then read/write to the device > > and you should see it. :) > > > > We need to make "hdparm -c 2" (and "hdparm -c 3") unsupported > > (see how "io_32bit" setting is handled in ide_add_generic_settings() > > and how it can be read-only or read-write setting depending on the > > value of drive->no_io_32bit). > > > > To do this we need to set drive->no_io_32bit to 1 (see how > > ide_disk_setup() handles it). Unfortunately 32-bit I/O capability > > is based on capabilities of both host and device so we have to > > add new flag hwif->no_io_32bit to indicate that host doesn't > > support 32-bit I/O. > > This all make sense, should I check for hwif->no_io_32bit in > idedisk_setup() and set drive->no_io_32bit to 1 if hwif->no_io_32bit > is 1 or do this the test in ide_add_generic_settings()?
Good question. idedisk_setup() seems more logical but in the current model "io_32bit" setting is still accessible without ide-disk driver through /proc/ide/ interface so...
Moreover the current drive->no_io_32bit code in ide-disk is wrong: * it shouldn't be overriding drive->no_io_32bit flag if it is 1 * doing this in ide-disk may be too late w.r.t. ide_add_generic_settings()
Therefore your previous suggestion is the right one - the best place to deal with ->no_io_32bit is ide-probe.c - doing this for all drives at the end of probe_hwif() should fix all above issues.
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