linux-kernelorg-stable/drivers/cxl
Dan Williams a32320b71f cxl/region: Add region autodiscovery
Region autodiscovery is an asynchronous state machine advanced by
cxl_port_probe(). After the decoders on an endpoint port are enumerated
they are scanned for actively enabled instances. Each active decoder is
flagged for auto-assembly CXL_DECODER_F_AUTO and attached to a region.
If a region does not already exist for the address range setting of the
decoder one is created. That creation process may race with other
decoders of the same region being discovered since cxl_port_probe() is
asynchronous. A new 'struct cxl_root_decoder' lock, @range_lock, is
introduced to mitigate that race.

Once all decoders have arrived, "p->nr_targets == p->interleave_ways",
they are sorted by their relative decode position. The sort algorithm
involves finding the point in the cxl_port topology where one leg of the
decode leads to deviceA and the other deviceB. At that point in the
topology the target order in the 'struct cxl_switch_decoder' indicates
the relative position of those endpoint decoders in the region.

>From that point the region goes through the same setup and validation
steps as user-created regions, but instead of programming the decoders
it validates that driver would have written the same values to the
decoders as were already present.

Tested-by: Fan Ni <fan.ni@samsung.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/167601999958.1924368.9366954455835735048.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-02-10 17:32:55 -08:00
..
core cxl/region: Add region autodiscovery 2023-02-10 17:32:55 -08:00
Kconfig cxl/region: Enable CONFIG_CXL_REGION to be toggled 2023-02-10 17:32:43 -08:00
Makefile cxl/pmem: Introduce nvdimm_security_ops with ->get_flags() operation 2022-11-30 16:30:47 -08:00
acpi.c cxl: update names for interleave ways conversion macros 2022-12-05 18:17:16 -08:00
cxl.h cxl/region: Add region autodiscovery 2023-02-10 17:32:55 -08:00
cxlmem.h cxl/memdev: Fix endpoint port removal 2023-02-10 17:29:09 -08:00
cxlpci.h cxl/pci: Move tracepoint definitions to drivers/cxl/core/ 2023-01-04 17:11:11 -08:00
mem.c cxl/port: Add RCD endpoint port enumeration 2022-12-05 10:32:26 -08:00
pci.c cxl/pci: Show opcode in debug messages when sending a command 2023-01-24 17:52:54 -08:00
pmem.c cxl/mbox: Enable cxl_mbox_send_cmd() users to validate output size 2022-12-06 14:36:02 -08:00
port.c cxl/region: Add region autodiscovery 2023-02-10 17:32:55 -08:00
security.c cxl/mbox: Enable cxl_mbox_send_cmd() users to validate output size 2022-12-06 14:36:02 -08:00