diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2022-01-31 16:34:40 -0800 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2022-02-08 22:57:29 -0800 |
| commit | a46cfc0f011ce77d120e1cdbf973f733d18f0105 (patch) | |
| tree | 23e0e0255d7b091d6532c672725d2adc253b61ac /drivers/cxl/cxl.h | |
| parent | 5ff7316f6fea4798c66b1ba953d1ebe6617503e4 (diff) | |
cxl/pmem: Introduce a find_cxl_root() helper
In preparation for switch port enumeration while also preserving the
potential for multi-domain / multi-root CXL topologies. Introduce a
'struct device' generic mechanism for retrieving a root CXL port, if one
is registered. Note that the only known multi-domain CXL configurations
are running the cxl_test unit test on a system that also publishes an
ACPI0017 device.
With this in hand the nvdimm-bridge lookup can be with
device_find_child() instead of bus_find_device() + custom mocked lookup
infrastructure in cxl_test.
The mechanism looks for a 2nd level port since the root level topology
is platform-firmware specific and the 2nd level down follows standard
PCIe topology expectations. The cxl_acpi 2nd level is associated with a
PCIe Root Port.
Reported-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/164367562182.225521.9488555616768096049.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/cxl/cxl.h')
| -rw-r--r-- | drivers/cxl/cxl.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 4d4cc8292137..61b0db526fa2 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -304,6 +304,7 @@ struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport, int cxl_add_dport(struct cxl_port *port, struct device *dport, int port_id, resource_size_t component_reg_phys); +struct cxl_port *find_cxl_root(struct device *dev); struct cxl_decoder *to_cxl_decoder(struct device *dev); bool is_root_decoder(struct device *dev); |