diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2021-06-09 19:01:35 +0300 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2021-06-10 04:02:38 +0300 |
| commit | 4812be97c015bddf12c70155858df43acc35a4eb (patch) | |
| tree | 5a00c36e1983f4b00bf38ef391f3d6d0d3a26b6c /drivers/cxl/cxl.h | |
| parent | 54ada34b4dfdb864ac602e13ff87581abe517ce9 (diff) | |
| download | linux-4812be97c015bddf12c70155858df43acc35a4eb.tar.xz | |
cxl/acpi: Introduce the root of a cxl_port topology
While CXL builds upon the PCI software model for enumeration and
endpoint control, a static platform component is required to bootstrap
the CXL memory layout. Similar to how ACPI identifies root-level PCI
memory resources, ACPI data enumerates the address space and interleave
configuration for CXL Memory.
In addition to identifying host bridges, ACPI is responsible for
enumerating the CXL memory space that can be addressed by downstream
decoders. This is similar to the requirement for ACPI to publish
resources via the _CRS method for PCI host bridges. Specifically, ACPI
publishes a table, CXL Early Discovery Table (CEDT), which includes a
list of CXL Memory resources, CXL Fixed Memory Window Structures
(CFMWS).
For now, introduce the core infrastructure for a cxl_port hierarchy
starting with a root level anchor represented by the ACPI0017 device.
Follow on changes model support for the configurable decode capabilities
of cxl_port instances, i.e. CXL switch support.
Co-developed-by: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/162325449515.2293126.15303270193010154608.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 | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 2c47e9cffd44..5651e5bb8274 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -8,6 +8,14 @@ #include <linux/bitops.h> #include <linux/io.h> +/** + * DOC: cxl objects + * + * The CXL core objects like ports, decoders, and regions are shared + * between the subsystem drivers cxl_acpi, cxl_pci, and core drivers + * (port-driver, region-driver, nvdimm object-drivers... etc). + */ + /* CXL 2.0 8.2.5 CXL.cache and CXL.mem Registers*/ #define CXL_CM_OFFSET 0x1000 #define CXL_CM_CAP_HDR_OFFSET 0x0 @@ -145,5 +153,28 @@ int cxl_map_device_regs(struct pci_dev *pdev, struct cxl_device_regs *regs, struct cxl_register_map *map); +#define CXL_RESOURCE_NONE ((resource_size_t) -1) + +/** + * struct cxl_port - logical collection of upstream port devices and + * downstream port devices to construct a CXL memory + * decode hierarchy. + * @dev: this port's device + * @uport: PCI or platform device implementing the upstream port capability + * @id: id for port device-name + * @component_reg_phys: component register capability base address (optional) + */ +struct cxl_port { + struct device dev; + struct device *uport; + int id; + resource_size_t component_reg_phys; +}; + +struct cxl_port *to_cxl_port(struct device *dev); +struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport, + resource_size_t component_reg_phys, + struct cxl_port *parent_port); + extern struct bus_type cxl_bus_type; #endif /* __CXL_H__ */ |