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tools/testing/cxl: Introduce a mocked-up CXL port hierarchy Create an environment for CXL plumbing unit tests. Especially when it comes to an algorithm for HDM Decoder (Host-managed Device Memory Decoder) programming, the availability of an in-kernel-tree emulation environment for CXL configuration complexity and corner cases speeds development and deters regressions. The approach taken mirrors what was done for tools/testing/nvdimm/. I.e. an external module, cxl_test.ko built out of the tools/testing/cxl/ directory, provides mock implementations of kernel APIs and kernel objects to simulate a real world device hierarchy. One feedback for the tools/testing/nvdimm/ proposal was "why not do this in QEMU?". In fact, the CXL development community has developed a QEMU model for CXL [1]. However, there are a few blocking issues that keep QEMU from being a tight fit for topology + provisioning unit tests: 1/ The QEMU community has yet to show interest in merging any of this support that has had patches on the list since November 2020. So, testing CXL to date involves building custom QEMU with out-of-tree patches. 2/ CXL mechanisms like cross-host-bridge interleave do not have a clear path to be emulated by QEMU without major infrastructure work. This is easier to achieve with the alloc_mock_res() approach taken in this patch to shortcut-define emulated system physical address ranges with interleave behavior. The QEMU enabling has been critical to get the driver off the ground, and may still move forward, but it does not address the ongoing needs of a regression testing environment and test driven development. This patch adds an ACPI CXL Platform definition with emulated CXL multi-ported host-bridges. A follow on patch adds emulated memory expander devices. Acked-by: Ben Widawsky <ben.widawsky@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20210202005948.241655-1-ben.widawsky@intel.com [1] Link: https://lore.kernel.org/r/163164680798.2831381.838684634806668012.stgit@dwillia2-desk3.amr.corp.intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-14 12:14:22 -07:00
cxl/test: Mock acpi_table_parse_cedt() Now that cxl_acpi has been converted to use the core ACPI CEDT sub-table parser, update cxl_test to inject CFMWS and CHBS data directly into cxl_acpi's handlers. Cc: Alison Schofield <alison.schofield@intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/r/163553711363.2509508.17428994087868269952.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-10-29 12:51:53 -07:00
tools/testing/cxl: Introduce a mocked-up CXL port hierarchy Create an environment for CXL plumbing unit tests. Especially when it comes to an algorithm for HDM Decoder (Host-managed Device Memory Decoder) programming, the availability of an in-kernel-tree emulation environment for CXL configuration complexity and corner cases speeds development and deters regressions. The approach taken mirrors what was done for tools/testing/nvdimm/. I.e. an external module, cxl_test.ko built out of the tools/testing/cxl/ directory, provides mock implementations of kernel APIs and kernel objects to simulate a real world device hierarchy. One feedback for the tools/testing/nvdimm/ proposal was "why not do this in QEMU?". In fact, the CXL development community has developed a QEMU model for CXL [1]. However, there are a few blocking issues that keep QEMU from being a tight fit for topology + provisioning unit tests: 1/ The QEMU community has yet to show interest in merging any of this support that has had patches on the list since November 2020. So, testing CXL to date involves building custom QEMU with out-of-tree patches. 2/ CXL mechanisms like cross-host-bridge interleave do not have a clear path to be emulated by QEMU without major infrastructure work. This is easier to achieve with the alloc_mock_res() approach taken in this patch to shortcut-define emulated system physical address ranges with interleave behavior. The QEMU enabling has been critical to get the driver off the ground, and may still move forward, but it does not address the ongoing needs of a regression testing environment and test driven development. This patch adds an ACPI CXL Platform definition with emulated CXL multi-ported host-bridges. A follow on patch adds emulated memory expander devices. Acked-by: Ben Widawsky <ben.widawsky@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20210202005948.241655-1-ben.widawsky@intel.com [1] Link: https://lore.kernel.org/r/163164680798.2831381.838684634806668012.stgit@dwillia2-desk3.amr.corp.intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-14 12:14:22 -07:00
cxl/pci: Move cxl_await_media_ready() to the core Allow cxl_await_media_ready() to be mocked for testing purposes rather than carrying the maintenance burden of an indirect function call in the mainline driver. With the move cxl_await_media_ready() can no longer reuse the mailbox timeout override, so add a media_ready_timeout module parameter to the core to backfill. Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/165291688340.1426646.4755627801983775011.stgit@dwillia2-xfh Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-05-18 16:34:43 -07:00
cxl/acpi: Probe RCRB later during RCH downstream port creation The RCRB is extracted already during ACPI CEDT table parsing while the data of this is needed not earlier than dport creation. This implementation comes with drawbacks: During ACPI table scan there is already MMIO access including mapping and unmapping, but only ACPI data should be collected here. The collected data must be transferred through a couple of interfaces until it is finally consumed when creating the dport. This causes complex data structures and function interfaces. Additionally, RCRB parsing will be extended to also extract AER data, it would be much easier do this at a later point during port and dport creation when the data structures are available to hold that data. To simplify all that, probe the RCRB at a later point during RCH downstream port creation. Change ACPI table parser to only extract the base address of either the component registers or the RCRB. Parse and extract the RCRB in devm_cxl_add_rch_dport(). This is in preparation to centralize all RCRB scanning. Signed-off-by: Robert Richter <rrichter@amd.com> Signed-off-by: Terry Bowman <terry.bowman@amd.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/20230622205523.85375-2-terry.bowman@amd.com Co-developed-by: Dan Williams <dan.j.williams@intel.com> Link: https://lore.kernel.org/r/20230622205523.85375-3-terry.bowman@amd.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-06-25 11:35:20 -07:00
cxl/test: Add support for qos_class checking Set a fake qos_class to a unique value in order to do simple testing of qos_class for root decoders and mem devs via user cxl_test. A mock function is added to set the fake qos_class values for memory device and overrides cxl_endpoint_parse_cdat() in cxl driver code. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240206190431.1810289-5-dave.jiang@intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-02-06 12:03:40 -07:00
cxl/test: Refactor decoder setup to reduce cxl_test burden Group the decoder setup code in switch and endpoint port probe into a single function for each to reduce the number of functions to be mocked in cxl_test. Introduce devm_cxl_switch_port_decoders_setup() and devm_cxl_endpoint_decoders_setup(). These two functions will be mocked instead with some functions optimized out since the mock version does not do anything. Remove devm_cxl_setup_hdm(), devm_cxl_add_passthrough_decoder(), and devm_cxl_enumerate_decoders() in cxl_test mock code. In turn, mock_cxl_add_passthrough_decoder() can be removed since cxl_test does not setup passthrough decoders. __wrap_cxl_hdm_decode_init() and __wrap_cxl_dvsec_rr_decode() can be removed as well since they only return 0 when called. [dj: drop 'struct cxl_port' forward declaration (Robert)] Suggested-by: Robert Richter <rrichter@amd.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Reviewed-by: Robert Richter <rrichter@amd.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2025-08-29 11:09:23 -07:00
cxl/test: Add support for acpi extended linear cache Add the mock wrappers for hmat_get_extended_linear_cache_size() in order to emulate the ACPI helper function for the regions that are mock'd by cxl_test. Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Tested-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Fabio M. De Francesco <fabio.m.de.francesco@linux.intel.com> Link: https://patch.msgid.link/20251117144611.903692-4-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2025-11-17 07:46:11 -07:00
cxl/port: Move dport probe operations to a driver event In preparation for adding more register setup to the cxl_port_add_dport() path (for RAS register mapping), move the dport creation event to a driver callback. This achieves two goals, it puts driver operations logically where they belong, in a driver, and it obviates the gymnastics of DECLARE_TESTABLE() which just makes a mess of grepping for CXL symbols. In other words, a driver callback is less of an ongoing maintenance burden than this DECLARE_TESTABLE arrangement that does not scale and diminishes the grep-ability of the codebase. cxl_port_add_dport() moves mostly unmodified from drivers/cxl/core/port.c. The only deliberate change is that it now assumes that the device_lock is held on entry and the driver is attached (just like cxl_port_probe()). Reviewed-by: Terry Bowman <terry.bowman@amd.com> Tested-by: Terry Bowman <terry.bowman@amd.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Link: https://patch.msgid.link/20260131000403.2135324-6-dan.j.williams@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-01-30 16:03:59 -08:00
tools/testing/cxl: Introduce a mocked-up CXL port hierarchy Create an environment for CXL plumbing unit tests. Especially when it comes to an algorithm for HDM Decoder (Host-managed Device Memory Decoder) programming, the availability of an in-kernel-tree emulation environment for CXL configuration complexity and corner cases speeds development and deters regressions. The approach taken mirrors what was done for tools/testing/nvdimm/. I.e. an external module, cxl_test.ko built out of the tools/testing/cxl/ directory, provides mock implementations of kernel APIs and kernel objects to simulate a real world device hierarchy. One feedback for the tools/testing/nvdimm/ proposal was "why not do this in QEMU?". In fact, the CXL development community has developed a QEMU model for CXL [1]. However, there are a few blocking issues that keep QEMU from being a tight fit for topology + provisioning unit tests: 1/ The QEMU community has yet to show interest in merging any of this support that has had patches on the list since November 2020. So, testing CXL to date involves building custom QEMU with out-of-tree patches. 2/ CXL mechanisms like cross-host-bridge interleave do not have a clear path to be emulated by QEMU without major infrastructure work. This is easier to achieve with the alloc_mock_res() approach taken in this patch to shortcut-define emulated system physical address ranges with interleave behavior. The QEMU enabling has been critical to get the driver off the ground, and may still move forward, but it does not address the ongoing needs of a regression testing environment and test driven development. This patch adds an ACPI CXL Platform definition with emulated CXL multi-ported host-bridges. A follow on patch adds emulated memory expander devices. Acked-by: Ben Widawsky <ben.widawsky@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20210202005948.241655-1-ben.widawsky@intel.com [1] Link: https://lore.kernel.org/r/163164680798.2831381.838684634806668012.stgit@dwillia2-desk3.amr.corp.intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-14 12:14:22 -07:00
cxl/test: Add mock version of devm_cxl_add_dport_by_dev() devm_cxl_add_dport_by_dev() outside of cxl_test is done through PCI hierarchy. However with cxl_test, it needs to be done through the platform device hierarchy. Add the mock function for devm_cxl_add_dport_by_dev(). When cxl_core calls a cxl_core exported function and that function is mocked by cxl_test, the call chain causes a circular dependency issue. Dan provided a workaround to avoid this issue. Apply the method to changes from the late dport allocation changes in order to enable cxl-test. In cxl_core they are defined with "__" added in front of the function. A macro is used to define the original function names for when non-test version of the kernel is built. A bit of macros and typedefs are used to allow mocking of those functions in cxl_test. Co-developed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Reviewed-by: Li Ming <ming.li@zohomail.com> Tested-by: Alison Schofield <alison.schofield@intel.com> Tested-by: Robert Richter <rrichter@amd.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2025-08-29 11:09:25 -07:00
cxl/pci: Move tracepoint definitions to drivers/cxl/core/ CXL is using tracepoints for reporting RAS capability register payloads for AER events, and has plans to use tracepoints for the output payload of Get Poison List and Get Event Records commands. For organization purposes it would be nice to keep those all under a single + local CXL trace system. This also organization also potentially helps in the future when CXL drivers expand beyond generic memory expanders, however that would also entail a move away from the expander-specific cxl_dev_state context, save that for later. Note that the powerpc-specific drivers/misc/cxl/ also defines a 'cxl' trace system, however, it is unlikely that a single platform will ever load both drivers simultaneously. Cc: Steven Rostedt <rostedt@goodmis.org> Tested-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/167051869176.436579.9728373544811641087.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-12-08 09:02:00 -08:00
tools/testing/cxl: Introduce a mocked-up CXL port hierarchy Create an environment for CXL plumbing unit tests. Especially when it comes to an algorithm for HDM Decoder (Host-managed Device Memory Decoder) programming, the availability of an in-kernel-tree emulation environment for CXL configuration complexity and corner cases speeds development and deters regressions. The approach taken mirrors what was done for tools/testing/nvdimm/. I.e. an external module, cxl_test.ko built out of the tools/testing/cxl/ directory, provides mock implementations of kernel APIs and kernel objects to simulate a real world device hierarchy. One feedback for the tools/testing/nvdimm/ proposal was "why not do this in QEMU?". In fact, the CXL development community has developed a QEMU model for CXL [1]. However, there are a few blocking issues that keep QEMU from being a tight fit for topology + provisioning unit tests: 1/ The QEMU community has yet to show interest in merging any of this support that has had patches on the list since November 2020. So, testing CXL to date involves building custom QEMU with out-of-tree patches. 2/ CXL mechanisms like cross-host-bridge interleave do not have a clear path to be emulated by QEMU without major infrastructure work. This is easier to achieve with the alloc_mock_res() approach taken in this patch to shortcut-define emulated system physical address ranges with interleave behavior. The QEMU enabling has been critical to get the driver off the ground, and may still move forward, but it does not address the ongoing needs of a regression testing environment and test driven development. This patch adds an ACPI CXL Platform definition with emulated CXL multi-ported host-bridges. A follow on patch adds emulated memory expander devices. Acked-by: Ben Widawsky <ben.widawsky@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20210202005948.241655-1-ben.widawsky@intel.com [1] Link: https://lore.kernel.org/r/163164680798.2831381.838684634806668012.stgit@dwillia2-desk3.amr.corp.intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-14 12:14:22 -07:00
tools/testing/cxl: Prevent cxl_test from confusing production modules The cxl_test machinery builds modified versions of the modules in drivers/cxl/ and intercepts some of their calls to allow cxl_test to inject mock CXL topologies for test. However, if cxl_test attempts the same with production modules, fireworks ensue as Luis discovered [1]. Prevent that scenario by arranging for cxl_test to check for a "watermark" symbol in each of the modules it expects to be modified before the test can run. This turns undefined runtime behavior or crashes into a safer failure to load the cxl_test module. Link: http://lore.kernel.org/r/20221209062919.1096779-1-mcgrof@kernel.org [1] Reported-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-12-13 08:44:24 -08:00
tools/testing/cxl: Introduce a mocked-up CXL port hierarchy Create an environment for CXL plumbing unit tests. Especially when it comes to an algorithm for HDM Decoder (Host-managed Device Memory Decoder) programming, the availability of an in-kernel-tree emulation environment for CXL configuration complexity and corner cases speeds development and deters regressions. The approach taken mirrors what was done for tools/testing/nvdimm/. I.e. an external module, cxl_test.ko built out of the tools/testing/cxl/ directory, provides mock implementations of kernel APIs and kernel objects to simulate a real world device hierarchy. One feedback for the tools/testing/nvdimm/ proposal was "why not do this in QEMU?". In fact, the CXL development community has developed a QEMU model for CXL [1]. However, there are a few blocking issues that keep QEMU from being a tight fit for topology + provisioning unit tests: 1/ The QEMU community has yet to show interest in merging any of this support that has had patches on the list since November 2020. So, testing CXL to date involves building custom QEMU with out-of-tree patches. 2/ CXL mechanisms like cross-host-bridge interleave do not have a clear path to be emulated by QEMU without major infrastructure work. This is easier to achieve with the alloc_mock_res() approach taken in this patch to shortcut-define emulated system physical address ranges with interleave behavior. The QEMU enabling has been critical to get the driver off the ground, and may still move forward, but it does not address the ongoing needs of a regression testing environment and test driven development. This patch adds an ACPI CXL Platform definition with emulated CXL multi-ported host-bridges. A follow on patch adds emulated memory expander devices. Acked-by: Ben Widawsky <ben.widawsky@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20210202005948.241655-1-ben.widawsky@intel.com [1] Link: https://lore.kernel.org/r/163164680798.2831381.838684634806668012.stgit@dwillia2-desk3.amr.corp.intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-14 12:14:22 -07:00
cxl/pmem: Introduce nvdimm_security_ops with ->get_flags() operation Add nvdimm_security_ops support for CXL memory device with the introduction of the ->get_flags() callback function. This is part of the "Persistent Memory Data-at-rest Security" command set for CXL memory device support. The ->get_flags() function provides the security state of the persistent memory device defined by the CXL 3.0 spec section 8.2.9.8.6.1. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/166983609611.2734609.13231854299523325319.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-11-30 12:21:36 -07:00
tools/testing/cxl: Introduce a mocked-up CXL port hierarchy Create an environment for CXL plumbing unit tests. Especially when it comes to an algorithm for HDM Decoder (Host-managed Device Memory Decoder) programming, the availability of an in-kernel-tree emulation environment for CXL configuration complexity and corner cases speeds development and deters regressions. The approach taken mirrors what was done for tools/testing/nvdimm/. I.e. an external module, cxl_test.ko built out of the tools/testing/cxl/ directory, provides mock implementations of kernel APIs and kernel objects to simulate a real world device hierarchy. One feedback for the tools/testing/nvdimm/ proposal was "why not do this in QEMU?". In fact, the CXL development community has developed a QEMU model for CXL [1]. However, there are a few blocking issues that keep QEMU from being a tight fit for topology + provisioning unit tests: 1/ The QEMU community has yet to show interest in merging any of this support that has had patches on the list since November 2020. So, testing CXL to date involves building custom QEMU with out-of-tree patches. 2/ CXL mechanisms like cross-host-bridge interleave do not have a clear path to be emulated by QEMU without major infrastructure work. This is easier to achieve with the alloc_mock_res() approach taken in this patch to shortcut-define emulated system physical address ranges with interleave behavior. The QEMU enabling has been critical to get the driver off the ground, and may still move forward, but it does not address the ongoing needs of a regression testing environment and test driven development. This patch adds an ACPI CXL Platform definition with emulated CXL multi-ported host-bridges. A follow on patch adds emulated memory expander devices. Acked-by: Ben Widawsky <ben.widawsky@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20210202005948.241655-1-ben.widawsky@intel.com [1] Link: https://lore.kernel.org/r/163164680798.2831381.838684634806668012.stgit@dwillia2-desk3.amr.corp.intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-14 12:14:22 -07:00
tools/testing/cxl: Prevent cxl_test from confusing production modules The cxl_test machinery builds modified versions of the modules in drivers/cxl/ and intercepts some of their calls to allow cxl_test to inject mock CXL topologies for test. However, if cxl_test attempts the same with production modules, fireworks ensue as Luis discovered [1]. Prevent that scenario by arranging for cxl_test to check for a "watermark" symbol in each of the modules it expects to be modified before the test can run. This turns undefined runtime behavior or crashes into a safer failure to load the cxl_test module. Link: http://lore.kernel.org/r/20221209062919.1096779-1-mcgrof@kernel.org [1] Reported-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-12-13 08:44:24 -08:00
tools/testing/cxl: Introduce a mocked-up CXL port hierarchy Create an environment for CXL plumbing unit tests. Especially when it comes to an algorithm for HDM Decoder (Host-managed Device Memory Decoder) programming, the availability of an in-kernel-tree emulation environment for CXL configuration complexity and corner cases speeds development and deters regressions. The approach taken mirrors what was done for tools/testing/nvdimm/. I.e. an external module, cxl_test.ko built out of the tools/testing/cxl/ directory, provides mock implementations of kernel APIs and kernel objects to simulate a real world device hierarchy. One feedback for the tools/testing/nvdimm/ proposal was "why not do this in QEMU?". In fact, the CXL development community has developed a QEMU model for CXL [1]. However, there are a few blocking issues that keep QEMU from being a tight fit for topology + provisioning unit tests: 1/ The QEMU community has yet to show interest in merging any of this support that has had patches on the list since November 2020. So, testing CXL to date involves building custom QEMU with out-of-tree patches. 2/ CXL mechanisms like cross-host-bridge interleave do not have a clear path to be emulated by QEMU without major infrastructure work. This is easier to achieve with the alloc_mock_res() approach taken in this patch to shortcut-define emulated system physical address ranges with interleave behavior. The QEMU enabling has been critical to get the driver off the ground, and may still move forward, but it does not address the ongoing needs of a regression testing environment and test driven development. This patch adds an ACPI CXL Platform definition with emulated CXL multi-ported host-bridges. A follow on patch adds emulated memory expander devices. Acked-by: Ben Widawsky <ben.widawsky@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20210202005948.241655-1-ben.widawsky@intel.com [1] Link: https://lore.kernel.org/r/163164680798.2831381.838684634806668012.stgit@dwillia2-desk3.amr.corp.intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-14 12:14:22 -07:00
cxl/port: Add a driver for 'struct cxl_port' objects 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 <lkp@intel.com> Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Co-developed-by: Dan Williams <dan.j.williams@intel.com> Link: https://lore.kernel.org/r/164374948116.464348.1772618057599155408.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-02-01 13:07:51 -08:00
tools/testing/cxl: Prevent cxl_test from confusing production modules The cxl_test machinery builds modified versions of the modules in drivers/cxl/ and intercepts some of their calls to allow cxl_test to inject mock CXL topologies for test. However, if cxl_test attempts the same with production modules, fireworks ensue as Luis discovered [1]. Prevent that scenario by arranging for cxl_test to check for a "watermark" symbol in each of the modules it expects to be modified before the test can run. This turns undefined runtime behavior or crashes into a safer failure to load the cxl_test module. Link: http://lore.kernel.org/r/20221209062919.1096779-1-mcgrof@kernel.org [1] Reported-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-12-13 08:44:24 -08:00
cxl/port: Add a driver for 'struct cxl_port' objects 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 <lkp@intel.com> Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Co-developed-by: Dan Williams <dan.j.williams@intel.com> Link: https://lore.kernel.org/r/164374948116.464348.1772618057599155408.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-02-01 13:07:51 -08:00
cxl/mem: Add the cxl_mem driver 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 <rdunlap@infradead.org> Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> [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 <dan.j.williams@intel.com>
2022-02-04 07:18:31 -08:00
tools/testing/cxl: Prevent cxl_test from confusing production modules The cxl_test machinery builds modified versions of the modules in drivers/cxl/ and intercepts some of their calls to allow cxl_test to inject mock CXL topologies for test. However, if cxl_test attempts the same with production modules, fireworks ensue as Luis discovered [1]. Prevent that scenario by arranging for cxl_test to check for a "watermark" symbol in each of the modules it expects to be modified before the test can run. This turns undefined runtime behavior or crashes into a safer failure to load the cxl_test module. Link: http://lore.kernel.org/r/20221209062919.1096779-1-mcgrof@kernel.org [1] Reported-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-12-13 08:44:24 -08:00
cxl/mem: Add the cxl_mem driver 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 <rdunlap@infradead.org> Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> [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 <dan.j.williams@intel.com>
2022-02-04 07:18:31 -08:00
tools/testing/cxl: Introduce a mocked-up CXL port hierarchy Create an environment for CXL plumbing unit tests. Especially when it comes to an algorithm for HDM Decoder (Host-managed Device Memory Decoder) programming, the availability of an in-kernel-tree emulation environment for CXL configuration complexity and corner cases speeds development and deters regressions. The approach taken mirrors what was done for tools/testing/nvdimm/. I.e. an external module, cxl_test.ko built out of the tools/testing/cxl/ directory, provides mock implementations of kernel APIs and kernel objects to simulate a real world device hierarchy. One feedback for the tools/testing/nvdimm/ proposal was "why not do this in QEMU?". In fact, the CXL development community has developed a QEMU model for CXL [1]. However, there are a few blocking issues that keep QEMU from being a tight fit for topology + provisioning unit tests: 1/ The QEMU community has yet to show interest in merging any of this support that has had patches on the list since November 2020. So, testing CXL to date involves building custom QEMU with out-of-tree patches. 2/ CXL mechanisms like cross-host-bridge interleave do not have a clear path to be emulated by QEMU without major infrastructure work. This is easier to achieve with the alloc_mock_res() approach taken in this patch to shortcut-define emulated system physical address ranges with interleave behavior. The QEMU enabling has been critical to get the driver off the ground, and may still move forward, but it does not address the ongoing needs of a regression testing environment and test driven development. This patch adds an ACPI CXL Platform definition with emulated CXL multi-ported host-bridges. A follow on patch adds emulated memory expander devices. Acked-by: Ben Widawsky <ben.widawsky@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20210202005948.241655-1-ben.widawsky@intel.com [1] Link: https://lore.kernel.org/r/163164680798.2831381.838684634806668012.stgit@dwillia2-desk3.amr.corp.intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-14 12:14:22 -07:00
cxl/core/port: Rename bus.c to port.c Given it is dominated by port infrastructure, and will only acquire more, rename bus.c to port.c. Reviewed-by: Ben Widawsky <ben.widawsky@intel.com> Link: https://lore.kernel.org/r/164298416136.3018233.15442880970000855425.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-01-23 16:29:21 -08:00
tools/testing/cxl: Introduce a mocked-up CXL port hierarchy Create an environment for CXL plumbing unit tests. Especially when it comes to an algorithm for HDM Decoder (Host-managed Device Memory Decoder) programming, the availability of an in-kernel-tree emulation environment for CXL configuration complexity and corner cases speeds development and deters regressions. The approach taken mirrors what was done for tools/testing/nvdimm/. I.e. an external module, cxl_test.ko built out of the tools/testing/cxl/ directory, provides mock implementations of kernel APIs and kernel objects to simulate a real world device hierarchy. One feedback for the tools/testing/nvdimm/ proposal was "why not do this in QEMU?". In fact, the CXL development community has developed a QEMU model for CXL [1]. However, there are a few blocking issues that keep QEMU from being a tight fit for topology + provisioning unit tests: 1/ The QEMU community has yet to show interest in merging any of this support that has had patches on the list since November 2020. So, testing CXL to date involves building custom QEMU with out-of-tree patches. 2/ CXL mechanisms like cross-host-bridge interleave do not have a clear path to be emulated by QEMU without major infrastructure work. This is easier to achieve with the alloc_mock_res() approach taken in this patch to shortcut-define emulated system physical address ranges with interleave behavior. The QEMU enabling has been critical to get the driver off the ground, and may still move forward, but it does not address the ongoing needs of a regression testing environment and test driven development. This patch adds an ACPI CXL Platform definition with emulated CXL multi-ported host-bridges. A follow on patch adds emulated memory expander devices. Acked-by: Ben Widawsky <ben.widawsky@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20210202005948.241655-1-ben.widawsky@intel.com [1] Link: https://lore.kernel.org/r/163164680798.2831381.838684634806668012.stgit@dwillia2-desk3.amr.corp.intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-14 12:14:22 -07:00
cxl/core: Generalize dport enumeration in the core The core houses infrastructure for decoder resources. A CXL port's dports are more closely related to decoder infrastructure than topology enumeration. Implement generic PCI based dport enumeration in the core, i.e. arrange for existing root port enumeration from cxl_acpi to share code with switch port enumeration which just amounts to a small difference in a pci_walk_bus() invocation once the appropriate 'struct pci_bus' has been retrieved. Set the convention that decoder objects are registered after all dports are enumerated. This enables userspace to know when the CXL core is finished establishing 'dportX' links underneath the 'portX' object. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/164368114191.354031.5270501846455462665.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-01-31 18:10:04 -08:00
cxl/core/hdm: Add CXL standard decoder enumeration to the core Unlike the decoder enumeration for "root decoders" described by platform firmware, standard decoders can be enumerated from the component registers space once the base address has been identified (via PCI, ACPI, or another mechanism). Add common infrastructure for HDM (Host-managed-Device-Memory) Decoder enumeration and share it between host-bridge, upstream switch port, and cxl_test defined decoders. The locking model for switch level decoders is to hold the port lock over the enumeration. This facilitates moving the dport and decoder enumeration to a 'port' driver. For now, the only enumerator of decoder resources is the cxl_acpi root driver. Co-developed-by: Ben Widawsky <ben.widawsky@intel.com> Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/164374688404.395335.9239248252443123526.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-02-01 12:24:30 -08:00
cxl/pci: Find and register CXL PMU devices CXL PMU devices can be found from entries in the Register Locator DVSEC. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/20230526095824.16336-4-Jonathan.Cameron@huawei.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-05-26 10:58:22 +01:00
cxl: Add callback to parse the DSMAS subtables from CDAT Provide a callback function to the CDAT parser in order to parse the Device Scoped Memory Affinity Structure (DSMAS). Each DSMAS structure contains the DPA range and its associated attributes in each entry. See the CDAT specification for details. The device handle and the DPA range is saved and to be associated with the DSLBIS locality data when the DSLBIS entries are parsed. The xarray is a local variable. When the total path performance data is calculated and storred this xarray can be discarded. Coherent Device Attribute Table 1.03 2.1 Device Scoped memory Affinity Structure (DSMAS) Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/170319619355.2212653.2675953129671561293.stgit@djiang5-mobl3 Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-12-21 15:03:13 -07:00
cxl/pci: Move tracepoint definitions to drivers/cxl/core/ CXL is using tracepoints for reporting RAS capability register payloads for AER events, and has plans to use tracepoints for the output payload of Get Poison List and Get Event Records commands. For organization purposes it would be nice to keep those all under a single + local CXL trace system. This also organization also potentially helps in the future when CXL drivers expand beyond generic memory expanders, however that would also entail a move away from the expander-specific cxl_dev_state context, save that for later. Note that the powerpc-specific drivers/misc/cxl/ also defines a 'cxl' trace system, however, it is unlikely that a single platform will ever load both drivers simultaneously. Cc: Steven Rostedt <rostedt@goodmis.org> Tested-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/167051869176.436579.9728373544811641087.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-12-08 09:02:00 -08:00
cxl/region: Add region creation support CXL 2.0 allows for dynamic provisioning of new memory regions (system physical address resources like "System RAM" and "Persistent Memory"). Whereas DDR and PMEM resources are conveyed statically at boot, CXL allows for assembling and instantiating new regions from the available capacity of CXL memory expanders in the system. Sysfs with an "echo $region_name > $create_region_attribute" interface is chosen as the mechanism to initiate the provisioning process. This was chosen over ioctl() and netlink() to keep the configuration interface entirely in a pseudo-fs interface, and it was chosen over configfs since, aside from this one creation event, the interface is read-mostly. I.e. configfs supports cases where an object is designed to be provisioned each boot, like an iSCSI storage target, and CXL region creation is mostly for PMEM regions which are created usually once per-lifetime of a server instance. This is an improvement over nvdimm that pre-created "seed" devices that tended to confuse users looking to determine which devices are active and which are idle. Recall that the major change that CXL brings over previous persistent memory architectures is the ability to dynamically define new regions. Compare that to drivers like 'nfit' where the region configuration is statically defined by platform firmware. Regions are created as a child of a root decoder that encompasses an address space with constraints. When created through sysfs, the root decoder is explicit. When created from an LSA's region structure a root decoder will possibly need to be inferred by the driver. Upon region creation through sysfs, a vacant region is created with a unique name. Regions have a number of attributes that must be configured before the region can be bound to the driver where HDM decoder program is completed. An example of creating a new region: - Allocate a new region name: region=$(cat /sys/bus/cxl/devices/decoder0.0/create_pmem_region) - Create a new region by name: while region=$(cat /sys/bus/cxl/devices/decoder0.0/create_pmem_region) ! echo $region > /sys/bus/cxl/devices/decoder0.0/create_pmem_region do true; done - Region now exists in sysfs: stat -t /sys/bus/cxl/devices/decoder0.0/$region - Delete the region, and name: echo $region > /sys/bus/cxl/devices/decoder0.0/delete_region Signed-off-by: Ben Widawsky <bwidawsk@kernel.org> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/165784333909.1758207.794374602146306032.stgit@dwillia2-xfh.jf.intel.com [djbw: simplify locking, reword changelog] Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-06-08 10:28:34 -07:00
cxl: Add mce notifier to emit aliased address for extended linear cache Below is a setup with extended linear cache configuration with an example layout of memory region shown below presented as a single memory region consists of 256G memory where there's 128G of DRAM and 128G of CXL memory. The kernel sees a region of total 256G of system memory. 128G DRAM 128G CXL memory |-----------------------------------|-------------------------------------| Data resides in either DRAM or far memory (FM) with no replication. Hot data is swapped into DRAM by the hardware behind the scenes. When error is detected in one location, it is possible that error also resides in the aliased location. Therefore when a memory location that is flagged by MCE is part of the special region, the aliased memory location needs to be offlined as well. Add an mce notify callback to identify if the MCE address location is part of an extended linear cache region and handle accordingly. Added symbol export to set_mce_nospec() in x86 code in order to call set_mce_nospec() from the CXL MCE notify callback. Link: https://lore.kernel.org/linux-cxl/668333b17e4b2_5639294fd@dwillia2-xfh.jf.intel.com.notmuch/ Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Li Ming <ming.li@zohomail.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://patch.msgid.link/20250226162224.3633792-5-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2025-02-26 09:21:21 -07:00
cxl: Add Get Supported Features command for kernel usage CXL spec r3.2 8.2.9.6.1 Get Supported Features (Opcode 0500h) The command retrieve the list of supported device-specific features (identified by UUID) and general information about each Feature. The driver will retrieve the Feature entries in order to make checks and provide information for the Get Feature and Set Feature command. One of the main piece of information retrieved are the effects a Set Feature command would have for a particular feature. The retrieved Feature entries are stored in the cxl_mailbox context. The setup of Features is initiated via devm_cxl_setup_features() during the pci probe function before the cxl_memdev is enumerated. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Li Ming <ming.li@zohomail.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Tested-by: Shiju Jose <shiju.jose@huawei.com> Link: https://patch.msgid.link/20250220194438.2281088-3-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2025-02-20 12:42:40 -07:00
cxl/edac: Add CXL memory device patrol scrub control feature CXL spec 3.2 section 8.2.10.9.11.1 describes the device patrol scrub control feature. The device patrol scrub proactively locates and makes corrections to errors in regular cycle. Allow specifying the number of hours within which the patrol scrub must be completed, subject to minimum and maximum limits reported by the device. Also allow disabling scrub allowing trade-off error rates against performance. Add support for patrol scrub control on CXL memory devices. Register with the EDAC device driver, which retrieves the scrub attribute descriptors from EDAC scrub and exposes the sysfs scrub control attributes to userspace. For example, scrub control for the CXL memory device "cxl_mem0" is exposed in /sys/bus/edac/devices/cxl_mem0/scrubX/. Additionally, add support for region-based CXL memory patrol scrub control. CXL memory regions may be interleaved across one or more CXL memory devices. For example, region-based scrub control for "cxl_region1" is exposed in /sys/bus/edac/devices/cxl_region1/scrubX/. [dj: A few formatting fixes from Jonathan] Reviewed-by: Dave Jiang <dave.jiang@intel.com> Co-developed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Shiju Jose <shiju.jose@huawei.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Link: https://patch.msgid.link/20250521124749.817-4-shiju.jose@huawei.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2025-05-21 13:47:41 +01:00
cxl/pci: Remove CXL VH handling in CONFIG_PCIEAER_CXL conditional blocks from core/pci.c Create new config CONFIG_CXL_RAS and put all CXL RAS items behind the config. The config will depend on CPER and PCIE AER to build. Move the related VH RAS code from core/pci.c to core/ras.c. Restricted CXL host (RCH) RAS functions will be moved in a future patch. Cc: Robert Richter <rrichter@amd.com> Reviewed-by: Joshua Hahn <joshua.hahnjy@gmail.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Co-developed-by: Terry Bowman <terry.bowman@amd.com> Signed-off-by: Terry Bowman <terry.bowman@amd.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Link: https://patch.msgid.link/20260114182055.46029-8-terry.bowman@amd.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-01-14 12:20:28 -06:00
cxl/pci: Move CXL driver's RCH error handling into core/ras_rch.c Restricted CXL Host (RCH) protocol error handling uses a procedure distinct from the CXL Virtual Hierarchy (VH) handling. This is because of the differences in the RCH and VH topologies. Improve the maintainability and add ability to enable/disable RCH handling. Move and combine the RCH handling code into a single block conditionally compiled with the CONFIG_CXL_RCH_RAS kernel config. Signed-off-by: Terry Bowman <terry.bowman@amd.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://patch.msgid.link/20260114182055.46029-9-terry.bowman@amd.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-01-14 12:20:29 -06:00
cxl: Enable AMD Zen5 address translation using ACPI PRMT Add AMD Zen5 support for address translation. Zen5 systems may be configured to use 'Normalized addresses'. Then, host physical addresses (HPA) are different from their system physical addresses (SPA). The endpoint has its own physical address space and an incoming HPA is already converted to the device's physical address (DPA). Thus it has interleaving disabled and CXL endpoints are programmed passthrough (DPA == HPA). Host Physical Addresses (HPAs) need to be translated from the endpoint to its CXL host bridge, esp. to identify the endpoint's root decoder and region's address range. ACPI Platform Runtime Mechanism (PRM) provides a handler to translate the DPA to its SPA. This is documented in: AMD Family 1Ah Models 00h–0Fh and Models 10h–1Fh ACPI v6.5 Porting Guide, Publication # 58088 https://www.amd.com/en/search/documentation/hub.html With Normalized Addressing this PRM handler must be used to translate an HPA of an endpoint to its SPA. Do the following to implement AMD Zen5 address translation: Introduce a new file core/atl.c to handle ACPI PRM specific address translation code. Naming is loosely related to the kernel's AMD Address Translation Library (CONFIG_AMD_ATL) but implementation does not depend on it, nor it is vendor specific. Use Kbuild and Kconfig options respectively to enable the code depending on architecture and platform options. AMD Zen5 systems support the ACPI PRM CXL Address Translation firmware call (see ACPI v6.5 Porting Guide, Address Translation - CXL DPA to System Physical Address). Firmware enables the PRM handler if the platform has address translation implemented. Check firmware and kernel support of ACPI PRM using the specific GUID. On success enable address translation by setting up the earlier introduced root port callback, see function cxl_prm_setup_translation(). Setup is done in cxl_setup_prm_address_translation(), it is the only function that needs to be exported. For low level PRM firmware calls, use the ACPI framework. Identify the region's interleaving ways by inspecting the address ranges. Also determine the interleaving granularity using the address translation callback. Note that the position of the chunk from one interleaving block to the next may vary and thus cannot be considered constant. Address offsets larger than the interleaving block size cannot be used to calculate the granularity. Thus, probe the granularity using address translation for various HPAs in the same interleaving block. [ dj: Add atl.o build to cxl_test ] Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Tested-by: Gregory Price <gourry@gourry.net> Signed-off-by: Robert Richter <rrichter@amd.com> Link: https://patch.msgid.link/20260114164837.1076338-11-rrichter@amd.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-01-27 11:12:31 -07:00
tools/testing/cxl: Introduce a mocked-up CXL port hierarchy Create an environment for CXL plumbing unit tests. Especially when it comes to an algorithm for HDM Decoder (Host-managed Device Memory Decoder) programming, the availability of an in-kernel-tree emulation environment for CXL configuration complexity and corner cases speeds development and deters regressions. The approach taken mirrors what was done for tools/testing/nvdimm/. I.e. an external module, cxl_test.ko built out of the tools/testing/cxl/ directory, provides mock implementations of kernel APIs and kernel objects to simulate a real world device hierarchy. One feedback for the tools/testing/nvdimm/ proposal was "why not do this in QEMU?". In fact, the CXL development community has developed a QEMU model for CXL [1]. However, there are a few blocking issues that keep QEMU from being a tight fit for topology + provisioning unit tests: 1/ The QEMU community has yet to show interest in merging any of this support that has had patches on the list since November 2020. So, testing CXL to date involves building custom QEMU with out-of-tree patches. 2/ CXL mechanisms like cross-host-bridge interleave do not have a clear path to be emulated by QEMU without major infrastructure work. This is easier to achieve with the alloc_mock_res() approach taken in this patch to shortcut-define emulated system physical address ranges with interleave behavior. The QEMU enabling has been critical to get the driver off the ground, and may still move forward, but it does not address the ongoing needs of a regression testing environment and test driven development. This patch adds an ACPI CXL Platform definition with emulated CXL multi-ported host-bridges. A follow on patch adds emulated memory expander devices. Acked-by: Ben Widawsky <ben.widawsky@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20210202005948.241655-1-ben.widawsky@intel.com [1] Link: https://lore.kernel.org/r/163164680798.2831381.838684634806668012.stgit@dwillia2-desk3.amr.corp.intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-14 12:14:22 -07:00
tools/testing/cxl: Prevent cxl_test from confusing production modules The cxl_test machinery builds modified versions of the modules in drivers/cxl/ and intercepts some of their calls to allow cxl_test to inject mock CXL topologies for test. However, if cxl_test attempts the same with production modules, fireworks ensue as Luis discovered [1]. Prevent that scenario by arranging for cxl_test to check for a "watermark" symbol in each of the modules it expects to be modified before the test can run. This turns undefined runtime behavior or crashes into a safer failure to load the cxl_test module. Link: http://lore.kernel.org/r/20221209062919.1096779-1-mcgrof@kernel.org [1] Reported-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-12-13 08:44:24 -08:00
cxl: Add cxl_num_decoders_committed() usage to cxl_test Commit 458ba8189cb4 ("cxl: Add cxl_decoders_committed() helper") missed the conversion for cxl_test. Add usage of cxl_num_decoders_committed() to replace the open coding. Suggested-by: Alison Schofield <alison.schofield@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fan Ni <fan.ni@samsung.com> Link: https://lore.kernel.org/r/169929160525.824083.11813222229025394254.stgit@djiang5-mobl3 Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-11-06 10:26:45 -07:00
tools/testing/cxl: Introduce a mocked-up CXL port hierarchy Create an environment for CXL plumbing unit tests. Especially when it comes to an algorithm for HDM Decoder (Host-managed Device Memory Decoder) programming, the availability of an in-kernel-tree emulation environment for CXL configuration complexity and corner cases speeds development and deters regressions. The approach taken mirrors what was done for tools/testing/nvdimm/. I.e. an external module, cxl_test.ko built out of the tools/testing/cxl/ directory, provides mock implementations of kernel APIs and kernel objects to simulate a real world device hierarchy. One feedback for the tools/testing/nvdimm/ proposal was "why not do this in QEMU?". In fact, the CXL development community has developed a QEMU model for CXL [1]. However, there are a few blocking issues that keep QEMU from being a tight fit for topology + provisioning unit tests: 1/ The QEMU community has yet to show interest in merging any of this support that has had patches on the list since November 2020. So, testing CXL to date involves building custom QEMU with out-of-tree patches. 2/ CXL mechanisms like cross-host-bridge interleave do not have a clear path to be emulated by QEMU without major infrastructure work. This is easier to achieve with the alloc_mock_res() approach taken in this patch to shortcut-define emulated system physical address ranges with interleave behavior. The QEMU enabling has been critical to get the driver off the ground, and may still move forward, but it does not address the ongoing needs of a regression testing environment and test driven development. This patch adds an ACPI CXL Platform definition with emulated CXL multi-ported host-bridges. A follow on patch adds emulated memory expander devices. Acked-by: Ben Widawsky <ben.widawsky@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20210202005948.241655-1-ben.widawsky@intel.com [1] Link: https://lore.kernel.org/r/163164680798.2831381.838684634806668012.stgit@dwillia2-desk3.amr.corp.intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-14 12:14:22 -07:00
tools/testing/cxl: Disable "missing prototypes / declarations" warnings Prevent warnings of the form: tools/testing/cxl/test/mock.c:44:6: error: no previous prototype for ‘__wrap_is_acpi_device_node’ [-Werror=missing-prototypes] tools/testing/cxl/test/mock.c:63:5: error: no previous prototype for ‘__wrap_acpi_table_parse_cedt’ [-Werror=missing-prototypes] tools/testing/cxl/test/mock.c:81:13: error: no previous prototype for ‘__wrap_acpi_evaluate_integer’ [-Werror=missing-prototypes] ...by locally disabling some warnings. It turns out that: Commit 0fcb70851fbf ("Makefile.extrawarn: turn on missing-prototypes globally") ...in addition to expanding in-tree coverage, also impacts out-of-tree module builds like those in tools/testing/cxl/. Filter out the warning options on unit test code that does not effect mainline builds. Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://lore.kernel.org/r/170543983780.460832.10920261849128601697.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-01-16 13:17:17 -08:00
tools/testing/cxl: Introduce a mocked-up CXL port hierarchy Create an environment for CXL plumbing unit tests. Especially when it comes to an algorithm for HDM Decoder (Host-managed Device Memory Decoder) programming, the availability of an in-kernel-tree emulation environment for CXL configuration complexity and corner cases speeds development and deters regressions. The approach taken mirrors what was done for tools/testing/nvdimm/. I.e. an external module, cxl_test.ko built out of the tools/testing/cxl/ directory, provides mock implementations of kernel APIs and kernel objects to simulate a real world device hierarchy. One feedback for the tools/testing/nvdimm/ proposal was "why not do this in QEMU?". In fact, the CXL development community has developed a QEMU model for CXL [1]. However, there are a few blocking issues that keep QEMU from being a tight fit for topology + provisioning unit tests: 1/ The QEMU community has yet to show interest in merging any of this support that has had patches on the list since November 2020. So, testing CXL to date involves building custom QEMU with out-of-tree patches. 2/ CXL mechanisms like cross-host-bridge interleave do not have a clear path to be emulated by QEMU without major infrastructure work. This is easier to achieve with the alloc_mock_res() approach taken in this patch to shortcut-define emulated system physical address ranges with interleave behavior. The QEMU enabling has been critical to get the driver off the ground, and may still move forward, but it does not address the ongoing needs of a regression testing environment and test driven development. This patch adds an ACPI CXL Platform definition with emulated CXL multi-ported host-bridges. A follow on patch adds emulated memory expander devices. Acked-by: Ben Widawsky <ben.widawsky@intel.com> Reported-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20210202005948.241655-1-ben.widawsky@intel.com [1] Link: https://lore.kernel.org/r/163164680798.2831381.838684634806668012.stgit@dwillia2-desk3.amr.corp.intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-14 12:14:22 -07:00