(SEMB) is unable to communicate to Storage Enclosure Processor (SEP), in
response to hard and soft resets it should among other things return value
0x7F in Status register. The weird side is that it means DRQ bit set, which
tells that reset request is not completed. It would be fine if SEMB was the
only device on port. But if SEMB connected to PMP or built into it, it may
block access to other devices sharing same SATA port.
Make some tunings/fixes to soft-reset handling to workaround the issue:
- ahci(4): request CLO on the port after soft reset to ignore DRQ bit;
- siis(4): gracefully reinitialize port after soft reset timeout (hardware
doesn't detect reset request completion in this case);
- mvs(4): if PMP is used, send dummy soft-reset to the PMP port to make it
clear DRQ bit for us.
For now this makes quirks in ata_pmp.c, hiding SEMB ports of SiI3726/SiI4726
PMPs, less important. Further, if hardware permit, I hope to implement real
SEMB support.
Instead of spinning in a tight loop for up to 15 seconds, polling for device
readiness while it spins up, return reset completion just after PHY reports
"connect well" or 100ms connection timeout. If device was found, use callout
for checking device readiness with 100ms period up to full 31 second timeout.
This fixes system freeze for 5-10 seconds on drives hot plug-in.
- make SATA SIMs announce capabilities to handle SDB with Notification bit;
- make PMP driver honor this SIMs capability;
- make SATA XPT to negotiate and enable this feature for ATAPI devices.
This feature allows supporting SATA ATAPI devices to inform system about
some events happened, that may require attention. In my case this allows
LG GH22LS50 SATA DVR-RW drive to report tray open/close events. Events
reported to CAM in form of AC_SCSI_AEN async. Further they could be used
as a hints for checking device status and reporting media change to upper
layers, for example, via spoiling mechanism of GEOM.
of proper value. It caused bunch of "EMPTY CRPB" messages and potentially
may cause premature requests completion, which could cause data corruption.
For most cases it seems enough to just reread register to get proper value.
To protect against worse cases - erase processed queue entries with
impossible values and ignore them if problem still happen.
driver for CAM ATA subsystem. This driver supports same hardware as
atamarvell, ataadaptec and atamvsata drivers from ata(4), but provides
many additional features, such as NCQ, PMP, etc.
