Messages in this thread | | | From | Kumar Gala <> | Subject | Re: RFC: Compact Flash True IDE Mode Driver | Date | Mon, 13 Feb 2006 16:13:18 -0600 |
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On Feb 13, 2006, at 2:21 PM, Bartlomiej Zolnierkiewicz wrote:
> 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.
Now I'm confused. If I understand the code, what I want is for the "io_32bit" setting to have its RW field set to SETTING_READ, such that drive->no_io_32bit can NOT be changed. Additionally, I want it set to 1 if hwif->no_io_32bit is 1.
Are you saying that at the end of probe_hwif() I should iterate over the drives for that hwif and set drive->no_io_32bit to 1 if hwif- >no_io_32bit is 1? If so, can I do this in the last loop that already exists that iterates over the drives?
Will I not also want to test hwif->no_io_32bit in idedisk_setup() to ensure that it can only set driver->no_io_32bit to 0 if hwif- >no_io32bit is 0?
- kumar
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