- device initiated power management (some devices support only this way);
- Automatic Partial to Slumber Transition (more power saving);
- DMA auto-activation (expected to slightly improve performance).
More features could be added later, when hardware supports.
- Unify bus reset/probe sequence. Whenever bus attached at boot or later,
CAM will automatically reset and scan it. It allows to remove duplicate
code from many drivers.
- Any bus, attached before CAM completed it's boot-time initialization,
will equally join to the process, delaying boot if needed.
- New kern.cam.boot_delay loader tunable should help controllers that
are still unable to register their buses in time (such as slow USB/
PCCard/ CardBus devices), by adding one more event to wait on boot.
- To allow synchronization between different CAM levels, concept of
requests priorities was extended. Priorities now split between several
"run levels". Device can be freezed at specified level, allowing higher
priority requests to pass. For example, no payload requests allowed,
until PMP driver enable port. ATA XPT negotiate transfer parameters,
periph driver configure caching and so on.
- Frozen requests are no more counted by request allocation scheduler.
It fixes deadlocks, when frozen low priority payload requests occupying
slots, required by higher levels to manage theit execution.
- Two last changes were holding proper ATA reinitialization and error
recovery implementation. Now it is done: SATA controllers and Port
Multipliers now implement automatic hot-plug and should correctly
recover from timeouts and bus resets.
- Improve SCSI error recovery for devices on buses without automatic sense
reporting, such as ATAPI or USB. For example, it allows CAM to wait, while
CD drive loads disk, instead of immediately return error status.
- Decapitalize diagnostic messages and make them more readable and sensible.
- Teach PMP driver to limit maximum speed on fan-out ports.
- Make boot wait for PMP scan completes, and make rescan more reliable.
- Fix pass driver, to return CCB to user level in case of error.
- Increase number of retries in cd driver, as device may return several UAs.
get required command protocol. But they have no idea about new commands,
such as DATA SET MANAGEMENT (TRIM). As soon as this info any way provided
by CAM, give controller specific instructions.
It makes MSI working there. Later (and cheaper) PCIe chips (3132/3531)
still randomly crashing system in few seconds of high MSI rates, generating
something inaporopriate, like NMI or "Fatal trap 30".
- Extend XPT-SIM transfer settings control API. Now it allows to report to
SATA SIM number of tags supported by each device, implement ATA mode and
SATA revision negotiation for both SATA and PATA SIMs.
- Make ahci(4) and siis(4) to use submitted maximum tag number, when
scheduling requests. It allows to support NCQ on devices with lower tags
count then controller supports.
- Make PMP driver to report attached devices connection speeds.
- Implement ATA mode negotiation between user settings, device and
controller capabilities.
- Move tagged queueing control from ADA to ATA XPT. It allows to control
device command queue length correctly. First step to support < 32 tags.
- Limit queue for non-tagged devices by 2 slots for ahci(4) and siis(4).
- Implement quirk matching for ATA devices.
- Move xpt_schedule_dev_sendq() from header to source file.
- Move delayed queue shrinking to the more expected place - element freeing.
- Remove some SCSIsms in ATA.
- Rework timeout handling, to make it more graceful for devices sharing
controller port (with PMP). Wait for other commands completion/timeout
before initiating recovery.
- Handle timeouts and fatal errors with port hard-reset. The rest of
recovery will be done by XPT on receiving async event. More gracefull
per-device soft-reset recovery can be implemented later.
Driver supports Serial ATA and ATAPI devices, Port Multipliers
(including FIS-based switching), hardware command queues (31 command
per port) and Native Command Queuing. This is probably the second on
popularity, after AHCI, type of SATA2 controllers, that benefits from
using CAM, because of hardware command queuing support.
Approved by: re (kib)
