kernel.git/tools/testing/cxl/test, branch linux-5.18.y

tools/testing/cxl: Add a physical_node link

2022-02-09T06:57:33Z

Emulate what ACPI does to link a host bridge platform firmware device to device node on the PCI bus. In this case it's just self referencing link, but it otherwise lets the tooling test out its lookup code. Link: https://lore.kernel.org/r/164298433209.3018233.18101085948127163720.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

tools/testing/cxl: Enumerate mock decoders

2022-02-09T06:57:33Z

Enumerate 2-decoders per switch port and endpoint in the cxl_test topology. Link: https://lore.kernel.org/r/164298432699.3018233.12131068635065601541.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

tools/testing/cxl: Mock one level of switches

2022-02-09T06:57:33Z

The CXL port enumeration process adds intermediate CXL ports that are discovered between "root" CXL ports enumerated by 'cxl_acpi' and endpoints enumerated by 'cxl_pci + cxl_mem'. Test the dynamic discovery of intermediate switch ports in a CXL topology. Link: https://lore.kernel.org/r/164298432189.3018233.13142151550113000967.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

tools/testing/cxl: Fix root port to host bridge assignment

2022-02-09T06:57:33Z

Mocked root-ports are meant to be round-robin assigned to host-bridges. Fixes: 67dcdd4d3b83 ("tools/testing/cxl: Introduce a mocked-up CXL port hierarchy") Link: https://lore.kernel.org/r/164298431629.3018233.14004377108116384485.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

tools/testing/cxl: Mock dvsec_ranges()

2022-02-09T06:57:33Z

For test purposes, pretend that that CXL DVSEC ranges are not in active use and the device is ready CXL.mem operation. Link: https://lore.kernel.org/r/164298431119.3018233.17175518196764977542.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

cxl/memdev: Add numa_node attribute

2022-02-09T06:57:32Z

While CXL memory targets will have their own memory target node, individual memory devices may be affinitized like other PCI devices. Emit that attribute for memdevs. Reviewed-by: Jonathan Cameron Link: https://lore.kernel.org/r/164298428430.3018233.16409089892707993289.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

cxl/pci: Emit device serial number

2022-02-09T06:57:32Z

Per the CXL specification (8.1.12.2 Memory Device PCIe Capabilities and Extended Capabilities) the Device Serial Number capability is mandatory. Emit it for user tooling to identify devices. It is reasonable to ask whether the attribute should be added to the list of PCI sysfs device attributes. The PCI layer can optionally emit it too, but the CXL subsystem is aiming to preserve its independence and the possibility of CXL topologies with non-PCI devices in it. To date that has only proven useful for the 'cxl_test' model, but as can be seen with seen with ACPI0016 devices, sometimes all that is needed is a platform firmware table to point to CXL Component Registers in MMIO space to define a "CXL" device. Reviewed-by: Jonathan Cameron Link: https://lore.kernel.org/r/164366608838.196598.16856227191534267098.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

cxl/pci: Implement wait for media active

2022-02-09T06:57:31Z

CXL 2.0 8.1.3.8.2 states: Memory_Active: When set, indicates that the CXL Range 1 memory is fully initialized and available for software use. Must be set within Range 1. Memory_Active_Timeout of deassertion of reset to CXL device if CXL.mem HwInit Mode=1 Unfortunately, Memory_Active can take quite a long time depending on media size (up to 256s per 2.0 spec). Provide a callback for the eventual establishment of CXL.mem operations via the 'cxl_mem' driver the 'struct cxl_memdev'. The implementation waits for 60s by default for now and can be overridden by the mbox_ready_time module parameter. Signed-off-by: Ben Widawsky [djbw: switch to sleeping wait] Reviewed-by: Jonathan Cameron Link: https://lore.kernel.org/r/164298427373.3018233.9309741847039301834.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

cxl/core/port: Remove @host argument for dport + decoder enumeration

2022-02-09T06:57:30Z

Now that dport and decoder enumeration is centralized in the port driver, the @host argument for these helpers can be made implicit. For the root port the host is the port's uport device (ACPI0017 for cxl_acpi), and for all other descendant ports the devm context is the parent of @port. Reviewed-by: Jonathan Cameron Reviewed-by: Ben Widawsky Link: https://lore.kernel.org/r/164375043390.484143.17617734732003230076.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

cxl/port: Add a driver for 'struct cxl_port' objects

2022-02-09T06:57:30Z

The need for a CXL port driver and a dedicated cxl_bus_type is driven by a need to simultaneously support 2 independent physical memory decode domains (cache coherent CXL.mem and uncached PCI.mmio) that also intersect at a single PCIe device node. A CXL Port is a device that advertises a CXL Component Register block with an "HDM Decoder Capability Structure". >From Documentation/driver-api/cxl/memory-devices.rst: Similar to how a RAID driver takes disk objects and assembles them into a new logical device, the CXL subsystem is tasked to take PCIe and ACPI objects and assemble them into a CXL.mem decode topology. The need for runtime configuration of the CXL.mem topology is also similar to RAID in that different environments with the same hardware configuration may decide to assemble the topology in contrasting ways. One may choose performance (RAID0) striping memory across multiple Host Bridges and endpoints while another may opt for fault tolerance and disable any striping in the CXL.mem topology. The port driver identifies whether an endpoint Memory Expander is connected to a CXL topology. If an active (bound to the 'cxl_port' driver) CXL Port is not found at every PCIe Switch Upstream port and an active "root" CXL Port then the device is just a plain PCIe endpoint only capable of participating in PCI.mmio and DMA cycles, not CXL.mem coherent interleave sets. The 'cxl_port' driver lets the CXL subsystem leverage driver-core infrastructure for setup and teardown of register resources and communicating device activation status to userspace. The cxl_bus_type can rendezvous the async arrival of platform level CXL resources (via the 'cxl_acpi' driver) with the asynchronous enumeration of Memory Expander endpoints, while also implementing a hierarchical locking model independent of the associated 'struct pci_dev' locking model. The locking for dport and decoder enumeration is now handled in the core rather than callers. For now the port driver only enumerates and registers CXL resources (downstream port metadata and decoder resources) later it will be used to take action on its decoders in response to CXL.mem region provisioning requests. Note1: cxlpci.h has long depended on pci.h, but port.c was the first to not include pci.h. Carry that dependency in cxlpci.h. Note2: cxl port enumeration and probing complicates CXL subsystem init to the point that it helps to have centralized debug logging of probe events in cxl_bus_probe(). Reported-by: kernel test robot Signed-off-by: Ben Widawsky Reviewed-by: Jonathan Cameron Co-developed-by: Dan Williams Link: https://lore.kernel.org/r/164374948116.464348.1772618057599155408.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams