From patchwork Mon Jan 24 00:28:38 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 12721213 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C104929CA for ; Mon, 24 Jan 2022 00:28:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1642984119; x=1674520119; h=subject:from:to:cc:date:message-id:mime-version: content-transfer-encoding; bh=O+MpZFnYgrZlyePty/+JLNKv2kOTRvJBvM66K63gDg8=; b=I1GOc6/Q0b2oG4LYqWwaK4gnGFxCwKU8pHGXUC+PCXzhbv1e0jbEcEIC n/JUnlktA7wpiv35FaisZEgj1sw2WGkthyHHCwqFlY7Mmb33BxDnBnI1X uNcWreNwtO+IZTe6qFecv81Z3Rx3frmYmQQdXyGWXhAz9g21tUYjqshiS xyr/PS7ITqQANt6fvgadXJpKLrI0h6hflX01wA9pbt8yI66nzAvN+8g37 sILw0I++b6dWH2Mthr5S9siFtD3uSRzigpHYht6BlZgemmijEAEvJfeCN IKs6fEf4+y6usBpG4mALDHTbSb18J9qxL2eEd9PLbHQC39EK4st1GnV9o Q==; X-IronPort-AV: E=McAfee;i="6200,9189,10236"; a="233292192" X-IronPort-AV: E=Sophos;i="5.88,311,1635231600"; d="scan'208";a="233292192" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Jan 2022 16:28:39 -0800 X-IronPort-AV: E=Sophos;i="5.88,311,1635231600"; d="scan'208";a="476536323" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.25]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Jan 2022 16:28:39 -0800 Subject: [PATCH v3 00/40] CXL.mem Topology Discovery and Hotplug Support From: Dan Williams To: linux-cxl@vger.kernel.org Cc: Ben Widawsky , Jonathan Cameron , Jonathan Cameron , Randy Dunlap , Jonathan Cameron , kernel test robot , linux-pci@vger.kernel.org, nvdimm@lists.linux.dev Date: Sun, 23 Jan 2022 16:28:38 -0800 Message-ID: <164298411792.3018233.7493009997525360044.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-3-g996c Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Changes since v2 [1]: - Rework the series to clarify the role of 'struct cxl_port' objects and fix hotplug bugs. - Drop the cxl_topology_host() concept. - Fix endpoint unregistration relative to port ->remove() and switch-port unregistration relative to to endpoint ->remove(). - Add cxl_test infrastructure to validate switch enumeration and various hotplug scenarios (see upcoming updates to the 'cxl' tool for the userspace side of this testing). - Add lockdep coverage of the CXL subsystem's use of the device_lock(). - Add a "Theory of Operation" section to Documentation/driver-api/cxl/memory-devices.rst describing the behavior and role of the 'struct bus_type cxl_bus_type' instance (see: [PATCH v3 24/40] cxl/port: Add a driver for 'struct cxl_port' objects). - For timeout scenarios like mailbox ready time, memory valid, memory active, use a sleeping wait rather than a spin wait - Add a 'serial' attribute to memory devices since CXL mandates device implement the PCIe Device Serial Number definition. - Rename report_status() / report_cmd_status() cxl_err() / cxl_cmd_err() (Jonathan) [1]: https://lore.kernel.org/r/20211202043750.3501494-1-ben.widawsky@intel.com --- The CXL subsystem enabling story so far has been concerned with enumerating the platform firmware described "root" level of a CXL topology (CXL capable Host Bridges and CXL platform address ranges), and the endpoint level (CXL Memory Expanders identified by PCIe class code). The next phase is connecting endpoints to that root description by an arbitrary number of intervening switch ports. The driver for CXL Memory Expanders, 'cxl_pci', registers a 'struct cxl_memdev' on the CXL bus. To date that device has only served as the entry point for submitting CXL Memory Device control and management commands. Now a new 'cxl_mem' driver takes that device and probes the topology to validate it is capable of CXL.mem operations. As 'cxl_mem' probes the topology it registers 'struct cxl_port' instances at each Upstream Switch Port that it finds on the walk to the CXL root. Each of those port device in turn attempt to attach to a 'cxl_port' driver. The 'cxl_port' probe process enumerates Downstream Ports and CXL HDM Decoder Capability structures. If cxl_port_probe() fails it unwinds all descendent ports that were previously registered and ultimately fails cxl_mem_probe() as result. This design lets CXL Port capabilities be enumerated late, and only in the presence of attached Memory Expander endpoints. - The first 16 patches are fixes and preparatory cleanups including support for validating usage of device_lock() in the subsystem. - Patches 17-24 centralize Downstream Port and HDM Decoder Capability enumeration in the core and then introduces the cxl_port driver. - Patches 25-33 validates the CXL.mem link came up in endpoints, adds core infrastructure to enumerate Swicht Ports, and adds the cxl_mem driver. - Patches 34 and 35 add endpoint decoder enumeration. - The last 5 patches add cxl_test infrastructure to validate all the mechanics of attaching and detaching cxl_port and cxl_memdev instances. See the Documentation updates in patch 24 for more details. --- Ben Widawsky (17): cxl: Rename CXL_MEM to CXL_PCI cxl/pci: Implement Interface Ready Timeout cxl: Flesh out register names cxl/pci: Add new DVSEC definitions cxl/acpi: Map component registers for Root Ports cxl: Introduce module_cxl_driver cxl/core: Convert decoder range to resource cxl/core/port: Clarify decoder creation cxl/core/port: Make passthrough decoder init implicit cxl/core: Track port depth cxl/port: Add a driver for 'struct cxl_port' objects cxl/pci: Store component register base in cxlds cxl/pci: Cache device DVSEC offset cxl/pci: Retrieve CXL DVSEC memory info cxl/pci: Implement wait for media active cxl/mem: Add the cxl_mem driver cxl/core/port: Add endpoint decoders Dan Williams (23): cxl/pci: Defer mailbox status checks to command timeouts cxl/core/port: Rename bus.c to port.c cxl/decoder: Hide physical address information from non-root cxl/core: Fix cxl_probe_component_regs() error message cxl: Prove CXL locking cxl/core/port: Use dedicated lock for decoder target list cxl/port: Introduce cxl_port_to_pci_bus() cxl/pmem: Introduce a find_cxl_root() helper cxl/port: Up-level cxl_add_dport() locking requirements to the caller cxl/pci: Rename pci.h to cxlpci.h cxl/core: Generalize dport enumeration in the core cxl/core/hdm: Add CXL standard decoder enumeration to the core cxl/core: Emit modalias for CXL devices cxl/core/port: Remove @host argument for dport + decoder enumeration cxl/pci: Emit device serial number cxl/memdev: Add numa_node attribute cxl/core/port: Add switch port enumeration cxl/core: Move target_list out of base decoder attributes tools/testing/cxl: Mock dvsec_ranges() tools/testing/cxl: Fix root port to host bridge assignment tools/testing/cxl: Mock one level of switches tools/testing/cxl: Enumerate mock decoders tools/testing/cxl: Add a physical_node link Documentation/ABI/testing/sysfs-bus-cxl | 36 + Documentation/driver-api/cxl/memory-devices.rst | 315 +++++ drivers/cxl/Kconfig | 44 + drivers/cxl/Makefile | 6 drivers/cxl/acpi.c | 151 -- drivers/cxl/core/Makefile | 4 drivers/cxl/core/bus.c | 675 ---------- drivers/cxl/core/core.h | 3 drivers/cxl/core/hdm.c | 253 ++++ drivers/cxl/core/memdev.c | 46 + drivers/cxl/core/pci.c | 98 ++ drivers/cxl/core/pmem.c | 18 drivers/cxl/core/port.c | 1483 +++++++++++++++++++++++ drivers/cxl/core/regs.c | 63 + drivers/cxl/cxl.h | 184 +++ drivers/cxl/cxlmem.h | 40 + drivers/cxl/cxlpci.h | 75 + drivers/cxl/mem.c | 221 +++ drivers/cxl/pci.c | 373 ++++-- drivers/cxl/pci.h | 34 - drivers/cxl/pmem.c | 12 drivers/cxl/port.c | 76 + drivers/nvdimm/nd-core.h | 2 lib/Kconfig.debug | 23 tools/testing/cxl/Kbuild | 22 tools/testing/cxl/mock_acpi.c | 74 - tools/testing/cxl/mock_mem.c | 10 tools/testing/cxl/mock_pmem.c | 24 tools/testing/cxl/test/cxl.c | 330 ++++- tools/testing/cxl/test/mem.c | 19 tools/testing/cxl/test/mock.c | 91 + tools/testing/cxl/test/mock.h | 8 32 files changed, 3591 insertions(+), 1222 deletions(-) delete mode 100644 drivers/cxl/core/bus.c create mode 100644 drivers/cxl/core/hdm.c create mode 100644 drivers/cxl/core/pci.c create mode 100644 drivers/cxl/core/port.c create mode 100644 drivers/cxl/cxlpci.h create mode 100644 drivers/cxl/mem.c delete mode 100644 drivers/cxl/pci.h create mode 100644 drivers/cxl/port.c create mode 100644 tools/testing/cxl/mock_mem.c delete mode 100644 tools/testing/cxl/mock_pmem.c base-commit: be185c2988b48db65348d94168c793bdbc8d23c3