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Diffstat (limited to 'drivers/cxl/Kconfig')
| -rw-r--r-- | drivers/cxl/Kconfig | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig new file mode 100644 index 000000000..8ea1d340e --- /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 |