summaryrefslogtreecommitdiffstats
path: root/drivers/cxl/Kconfig
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/cxl/Kconfig')
-rw-r--r--drivers/cxl/Kconfig157
1 files changed, 157 insertions, 0 deletions
diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig
new file mode 100644
index 0000000000..8ea1d340e4
--- /dev/null
+++ b/drivers/cxl/Kconfig
@@ -0,0 +1,157 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menuconfig CXL_BUS
+ tristate "CXL (Compute Express Link) Devices Support"
+ depends on PCI
+ select FW_LOADER
+ select FW_UPLOAD
+ select PCI_DOE
+ help
+ CXL is a bus that is electrically compatible with PCI Express, but
+ layers three protocols on that signalling (CXL.io, CXL.cache, and
+ CXL.mem). The CXL.cache protocol allows devices to hold cachelines
+ locally, the CXL.mem protocol allows devices to be fully coherent
+ memory targets, the CXL.io protocol is equivalent to PCI Express.
+ Say 'y' to enable support for the configuration and management of
+ devices supporting these protocols.
+
+if CXL_BUS
+
+config CXL_PCI
+ tristate "PCI manageability"
+ default CXL_BUS
+ help
+ The CXL specification defines a "CXL memory device" sub-class in the
+ PCI "memory controller" base class of devices. Device's identified by
+ this class code provide support for volatile and / or persistent
+ memory to be mapped into the system address map (Host-managed Device
+ Memory (HDM)).
+
+ Say 'y/m' to enable a driver that will attach to CXL memory expander
+ devices enumerated by the memory device class code for configuration
+ and management primarily via the mailbox interface. See Chapter 2.3
+ Type 3 CXL Device in the CXL 2.0 specification for more details.
+
+ If unsure say 'm'.
+
+config CXL_MEM_RAW_COMMANDS
+ bool "RAW Command Interface for Memory Devices"
+ depends on CXL_PCI
+ help
+ Enable CXL RAW command interface.
+
+ The CXL driver ioctl interface may assign a kernel ioctl command
+ number for each specification defined opcode. At any given point in
+ time the number of opcodes that the specification defines and a device
+ may implement may exceed the kernel's set of associated ioctl function
+ numbers. The mismatch is either by omission, specification is too new,
+ or by design. When prototyping new hardware, or developing / debugging
+ the driver it is useful to be able to submit any possible command to
+ the hardware, even commands that may crash the kernel due to their
+ potential impact to memory currently in use by the kernel.
+
+ If developing CXL hardware or the driver say Y, otherwise say N.
+
+config CXL_ACPI
+ tristate "CXL ACPI: Platform Support"
+ depends on ACPI
+ default CXL_BUS
+ select ACPI_TABLE_LIB
+ help
+ Enable support for host managed device memory (HDM) resources
+ published by a platform's ACPI CXL memory layout description. See
+ Chapter 9.14.1 CXL Early Discovery Table (CEDT) in the CXL 2.0
+ specification, and CXL Fixed Memory Window Structures (CEDT.CFMWS)
+ (https://www.computeexpresslink.org/spec-landing). The CXL core
+ consumes these resource to publish the root of a cxl_port decode
+ hierarchy to map regions that represent System RAM, or Persistent
+ Memory regions to be managed by LIBNVDIMM.
+
+ If unsure say 'm'.
+
+config CXL_PMEM
+ tristate "CXL PMEM: Persistent Memory Support"
+ depends on LIBNVDIMM
+ default CXL_BUS
+ help
+ In addition to typical memory resources a platform may also advertise
+ support for persistent memory attached via CXL. This support is
+ managed via a bridge driver from CXL to the LIBNVDIMM system
+ subsystem. Say 'y/m' to enable support for enumerating and
+ provisioning the persistent memory capacity of CXL memory expanders.
+
+ If unsure say 'm'.
+
+config CXL_MEM
+ tristate "CXL: Memory Expansion"
+ depends on CXL_PCI
+ default CXL_BUS
+ help
+ The CXL.mem protocol allows a device to act as a provider of "System
+ RAM" and/or "Persistent Memory" that is fully coherent as if the
+ memory were attached to the typical CPU memory controller. This is
+ known as HDM "Host-managed Device Memory".
+
+ Say 'y/m' to enable a driver that will attach to CXL.mem devices for
+ memory expansion and control of HDM. See Chapter 9.13 in the CXL 2.0
+ specification for a detailed description of HDM.
+
+ If unsure say 'm'.
+
+config CXL_PORT
+ default CXL_BUS
+ tristate
+
+config CXL_SUSPEND
+ def_bool y
+ depends on SUSPEND && CXL_MEM
+
+config CXL_REGION
+ bool "CXL: Region Support"
+ default CXL_BUS
+ # For MAX_PHYSMEM_BITS
+ depends on SPARSEMEM
+ select MEMREGION
+ select GET_FREE_REGION
+ help
+ Enable the CXL core to enumerate and provision CXL regions. A CXL
+ region is defined by one or more CXL expanders that decode a given
+ system-physical address range. For CXL regions established by
+ platform-firmware this option enables memory error handling to
+ identify the devices participating in a given interleaved memory
+ range. Otherwise, platform-firmware managed CXL is enabled by being
+ placed in the system address map and does not need a driver.
+
+ If unsure say 'y'
+
+config CXL_REGION_INVALIDATION_TEST
+ bool "CXL: Region Cache Management Bypass (TEST)"
+ depends on CXL_REGION
+ help
+ CXL Region management and security operations potentially invalidate
+ the content of CPU caches without notifying those caches to
+ invalidate the affected cachelines. The CXL Region driver attempts
+ to invalidate caches when those events occur. If that invalidation
+ fails the region will fail to enable. Reasons for cache
+ invalidation failure are due to the CPU not providing a cache
+ invalidation mechanism. For example usage of wbinvd is restricted to
+ bare metal x86. However, for testing purposes toggling this option
+ can disable that data integrity safety and proceed with enabling
+ regions when there might be conflicting contents in the CPU cache.
+
+ If unsure, or if this kernel is meant for production environments,
+ say N.
+
+config CXL_PMU
+ tristate "CXL Performance Monitoring Unit"
+ default CXL_BUS
+ depends on PERF_EVENTS
+ help
+ Support performance monitoring as defined in CXL rev 3.0
+ section 13.2: Performance Monitoring. CXL components may have
+ one or more CXL Performance Monitoring Units (CPMUs).
+
+ Say 'y/m' to enable a driver that will attach to performance
+ monitoring units and provide standard perf based interfaces.
+
+ If unsure say 'm'.
+endif