linux/drivers/cxl
Davidlohr Bueso ccadf1310f cxl/mbox: Add background cmd handling machinery
This adds support for handling background operations, as defined in
the CXL 3.0 spec. Commands that can take too long (over ~2 seconds)
can run in the background asynchronously (to the hardware).

The driver will deal with such commands synchronously, blocking all
other incoming commands for a specified period of time, allowing
time-slicing the command such that the caller can send incremental
requests to avoid monopolizing the driver/device. Any out of sync
(timeout) between the driver and hardware is just disregarded as
an invalid state until the next successful submission. Such timeouts
are considered a rare occurrence, either a real device problem or a
driver issue that needs to reduce the size of the background operation
to fit the timeout.

On devices where mbox interrupts are supported, this will still use
a poller that will wakeup in the specified wait intervals. The irq
handler will simply awake the blocked cmd, which is also safe vs a
task that is either waking (timing out) or already awoken. Similarly
any irq setup error during the probing falls back to polling, thus
avoids unnecessarily erroring out.

Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/20230523170927.20685-5-dave@stgolabs.net
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-05-23 12:55:12 -07:00
..
core cxl/mbox: Add background cmd handling machinery 2023-05-23 12:55:12 -07:00
acpi.c Merge branch 'for-6.3/cxl-ram-region' into cxl/next 2023-02-10 18:11:01 -08:00
cxl.h cxl/mbox: Add background cmd handling machinery 2023-05-23 12:55:12 -07:00
cxlmem.h cxl/mbox: Add background cmd handling machinery 2023-05-23 12:55:12 -07:00
cxlpci.h cxl: Wait Memory_Info_Valid before access memory related info 2023-05-18 16:42:41 -07:00
Kconfig Merge branch 'for-6.3/cxl-ram-region' into cxl/next 2023-02-10 18:11:01 -08:00
Makefile cxl/pmem: Introduce nvdimm_security_ops with ->get_flags() operation 2022-11-30 16:30:47 -08:00
mem.c cxl: Move cxl_await_media_ready() to before capacity info retrieval 2023-05-18 16:43:45 -07:00
pci.c cxl/mbox: Add background cmd handling machinery 2023-05-23 12:55:12 -07:00
pmem.c cxl/pmem: Fix nvdimm registration races 2023-02-13 17:01:05 -08:00
port.c cxl: Move cxl_await_media_ready() to before capacity info retrieval 2023-05-18 16:43:45 -07:00
security.c cxl/mbox: Enable cxl_mbox_send_cmd() users to validate output size 2022-12-06 14:36:02 -08:00