Mark Lord wrote:
Tejun Heo wrote:
I've been studying things for last two days and discovered a number of
things. I'll soon post patch series. Thanks a lot for digging into
PMP stuff. It's great to have someone else's eyes on this stuff.
..
Yeah. It really does help when two or more people totally independently
implement a driver on top of something like that. For the most part,
this stuff seems to be working rather well, though. Good job!
Gwendal has been complaining to me about undetected drives on PMP
with sata_mv. My patchset to fix much of that will be posted here shortly.
But apparently, even with those fixes, he *still* has troubles,
though not as bad as before. I'm trying to get a nice annotated trace
from him so we can debug that further -- could be due to some of the
stuff you are looking at too, I suppose.
Issues I've found are...
* PMP r/w timeout is too short. It's currently 250ms. This is from
SIMG PMPs and was mainly to avoid longish sequential multiple timeouts
when access PMP regs via polled commands which is not the case
anymore and mv 4140 needs more time occasionally.
* SDB Notify is not masked during fan-out port resets if PMP hasn't been
reset in that pass. This causes PMP register access failure because
SDB Notify is received while PMP register write is in progress for
fan-out reset. I missed this because most of my testing was before
PMP register access was converted to IRQ driven.
* With the above two fixed, this is peripheral but this is what
triggered the above two on initial probes. ata_lpm_schedule() is
called during probe right after SCSI scan is complete which schedules
EH immediately, reliably triggering above two on certain hardware
combinations.
* sil3124/32 and mv4140 combination for some reason can't do NCQ
reliably. I don't know why. I'll blacklist it for the time being
and contact both companies about this.
* recovered errors shouldn't trigger resets. (this is peripheral too
with the first two issues fixed).
I have 8 patches to address the above issues && obscure hotplug
problems. I'll send the patches once after more testing.
Thanks.
--
tejun
--
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
