There is a condition whereby TCs (task contexts) can jump to the head of
the round robin queue causing indefinite starvation of pending tasks.
Posting a TC to a suspended RNC (remote node context) causes the
hardware to select that task first, but since the RNC is suspended the
scheduler proceeds to the next task in the expected round robin fashion,
restoring TC arbitration fairness.
Signed-off-by: Tomasz Chudy <tomasz.chudy@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Prepare the timer api for the arrival of dynamic creation and
destruction events from the core. It pretended to do this previously
but the core to date only used it in a static init-time only fashion.
This is an interim fix until a cleaner event queue can be developed.
1/ make all locking external to the api (add WARN_ONCE to verify)
2/ add a timer_destroy interface (to be used by the core)
3/ use del_timer_sync() prior to deallocating timer data
4/ delete the "timer_list" indirection, we only have timers allocated
for the isci_host
5/ fix detection of timer list allocation errors
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Undo the open coded and incorrect translation of the oem parameter sas
address to its libsas expected format.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Moved the firmware loading from per adapter to per PCI device. This should
prevent firmware from being loaded twice becuase of 2 SCU controller per
PCI device. We do have to do it per PCI device because request_firmware()
requires a struct device passed in.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Polling the event queue during scan is an unneeded holdover from the
original driver.
Signed-off-by: Edmund Nadolski <edmund.nadolski@intel.com>
[djbw: ensure we flush all port events and domain discovery]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The lldd actively disallows requests in the "starting" state. Retrying
or holding off commands in this state is sub-optimal:
1/ it adds another state check to the fast path
2/ retrying can cause libsas to give up
However, isci's ->lldd_dev_found() routine already waits for controller
start to complete before allowing further progress. Checking the
"starting" state in isci_task_execute_task and the isr is redundant and
misleading. Clean this up and introduce a controller-wide event queue
to start reeling in "completion" proliferation in the driver.
The "stopping" state cleanups are in a similar vein, rely on the the isr
and other paths being precluded from occurring rather than implementing
state checking logic.
Reported-by: Christoph Hellwig <hch@infradead.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Edmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The indirection is unecessary and broken in the current case that assigns the
handlers based on a not up-to-date pdev->msix_enabled value.
Route the handlers directly to the requisite core routines.
Todo: hook up error interrupt handling
Reported-by: Jeff Garzik <jeff@garzik.org>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Edmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Support for the up to 2x4-port 6Gb/s SAS controllers embedded in the
chipset.
This is a snapshot of the first publicly available version of the driver,
commit 4c1db2d0 in the 'historical' branch.
git://git.kernel.org/pub/scm/linux/kernel/git/djbw/isci.git historical
Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Edmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>