Switch driver to use MSIX mask and unmask instead of the ignore bit.
When ignore bit is cleared, we must issue an MMIO read to ensure writes
have all arrived and check and process any additional completions. The
ignore bit does not queue up any pending MSIX interrupts. The mask bit
however does. Use API call from interrupt subsystem to mask MSIX
interrupt since the hardware does not have convenient mask bit register.
Suggested-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/159319517621.70410.11816465052708900506.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Add wq drain support. When a wq is being released, it needs to wait for
all in-flight operation to complete. A device control function
idxd_wq_drain() has been added to facilitate this. A wq drain call
is added to the char dev on release to make sure all user operations are
complete. A wq drain is also added before the wq is being disabled.
A drain command can take an unpredictable period of time. Interrupt support
for device commands is added to allow waiting on the command to
finish. If a previous command is in progress, the new submitter can block
until the current command is finished before proceeding. The interrupt
based submission will submit the command and then wait until a command
completion interrupt happens to complete. All commands are moved to the
interrupt based command submission except for the device reset during
probe, which will be polled.
Fixes: 42d279f913 ("dmaengine: idxd: add char driver to expose submission portal to userland")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/159319502515.69593.13451647706946040301.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Create a char device region that will allow acquisition of user portals in
order to allow applications to submit DMA operations. A char device will be
created per work queue that gets exposed. The workqueue type "user"
is used to mark a work queue for user char device. For example if the
workqueue 0 of DSA device 0 is marked for char device, then a device node
of /dev/dsa/wq0.0 will be created.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/157965026985.73301.976523230037106742.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The device is left unconfigured when the driver is loaded. Various
components are configured via the driver sysfs attributes. Once
configuration is done, the device can be enabled by writing the device name
to the bind attribute of the device driver sysfs. Disabling can be done
similarly. Also the individual work queues can also be enabled and disabled
through the bind/unbind attributes. A constructed hierarchy is created
through the struct device framework in order to provide appropriate
configuration points and device state and status. This hierarchy is
presented off the virtual DSA bus.
i.e. /sys/bus/dsa/...
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/157965024585.73301.6431413676230150589.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
