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

tools/testing/cxl: Add a physical_node link

2022-02-09T06:57:33+00:00

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

2022-02-09T06:57:33+00:00

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

2022-02-09T06:57:33+00:00

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

2022-02-09T06:57:33+00:00

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()

2022-02-09T06:57:33+00:00

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/mem: Add the cxl_mem driver

2022-02-09T06:57:32+00:00

At this point the subsystem can enumerate all CXL ports (CXL.mem decode resources in upstream switch ports and host bridges) in a system. The last mile is connecting those ports to endpoints. The cxl_mem driver connects an endpoint device to the platform CXL.mem protoctol decode-topology. At ->probe() time it walks its device-topology-ancestry and adds a CXL Port object at every Upstream Port hop until it gets to CXL root. The CXL root object is only present after a platform firmware driver registers platform CXL resources. For ACPI based platform this is managed by the ACPI0017 device and the cxl_acpi driver. The ports are registered such that disabling a given port automatically unregisters all descendant ports, and the chain can only be registered after the root is established. Given ACPI device scanning may run asynchronously compared to PCI device scanning the root driver is tasked with rescanning the bus after the root successfully probes. Conversely if any ports in a chain between the root and an endpoint becomes disconnected it subsequently triggers the endpoint to unregister. Given lock depenedencies the endpoint unregistration happens in a workqueue asynchronously. If userspace cares about synchronizing delayed work after port events the /sys/bus/cxl/flush attribute is available for that purpose. Reported-by: Randy Dunlap Signed-off-by: Ben Widawsky Reviewed-by: Jonathan Cameron [djbw: clarify changelog, rework hotplug support] Link: https://lore.kernel.org/r/164398782997.903003.9725273241627693186.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

cxl/memdev: Add numa_node attribute

2022-02-09T06:57:32+00:00

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

2022-02-09T06:57:32+00:00

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

2022-02-09T06:57:31+00:00

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

2022-02-09T06:57:30+00:00

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