On 01/29/10 11:34 PM, Cyril Plisko wrote:
> On Sat, Jan 30, 2010 at 2:35 AM, Garrett D'Amore<gdamore at sun.com> wrote:
>
>> Looking around at stale code (I'm weird), I see this sbusmem driver that
>> seems to support a simple read/write function and devmap. No block device
>> support, and most likely of limited value. I can't seem to find any use for
>> it, and the sbus systems I can log into don't seem to actually have one of
>> the necessary devices.
>>
>> I'm wondering if this is another legacy RAM expansion device from the old
>> 32-bit sun4c/4m days that perhaps we can just remove?
>>
> That is not a a RAM driver of any sort. sbusmem allows you to mmap
> your SBus card and to meddle in the cards registers.
> Essentially it let you to have a userland driver for an arbitrary SBus card.
>
Okay, that makes sense.
Anyone know if it is actually *used* by anything? Or is this just one
of those ideas that seemed great at the time but found little use?
If anyone has ever found it useful, I'm inclined to leave it in the tree
until we finally gut sbus itself -- although I *suspect* that it may be
another whole release before we can do that. (Enterprise class systems
which are not yet EOSL have sbus on them. That said, it would appear
that the last of these reaches EOSL at the end of this year.)
- Garrett
>
>
>> Can anyone else enlighten me here? Is there some function that this thing
>> still serves that I'm not aware of.
>>
>> (Yes, "sbus" systems are still in use... Sunfire/Campfire and Starfire
>> systems are all Sbus, and there may be folks with Ultra-2's still using it
>> as well.)
>>
>> - Garrett
>>
>>
>
>
