summaryrefslogtreecommitdiff
path: root/drivers/cxl
AgeCommit message (Collapse)Author
2024-10-25cxl/port: Prevent out-of-order decoder allocationDan Williams
With the recent change to allow out-of-order decoder de-commit it highlights a need to strengthen the in-order decoder commit guarantees. As it stands match_free_decoder() ensures that if 2 regions are racing decoder allocations the one that wins the race will get the lower id decoder, but that still leaves the race to *commit* the decoder. Rather than have this complicated case of "reserved in-order, but may still commit out-of-order", just arrange for the reservation order to match the commit-order. In other words, prevent subsequent allocations until the last reservation is committed. This precludes overlapping region creation events and requires the previous regionN to either move forward to the decoder commit stage or drop its reservation before regionN+1 can move forward. That is, provided that regionN and regionN+1 decode through the same switch port. As a side effect this allows match_free_decoder() to drop its dependency on needing write access to the device_find_child() @data parameter [1]. Reported-by: Zijun Hu <quic_zijuhu@quicinc.com> Closes: http://lore.kernel.org/20240905-const_dfc_prepare-v4-0-4180e1d5a244@quicinc.com Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://patch.msgid.link/172964783668.81806.14962699553881333486.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2024-10-25cxl/port: Fix use-after-free, permit out-of-order decoder shutdownDan Williams
In support of investigating an initialization failure report [1], cxl_test was updated to register mock memory-devices after the mock root-port/bus device had been registered. That led to cxl_test crashing with a use-after-free bug with the following signature: cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem0:decoder7.0 @ 0 next: cxl_switch_uport.0 nr_eps: 1 nr_targets: 1 cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem4:decoder14.0 @ 1 next: cxl_switch_uport.0 nr_eps: 2 nr_targets: 1 cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[0] = cxl_switch_dport.0 for mem0:decoder7.0 @ 0 1) cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[1] = cxl_switch_dport.4 for mem4:decoder14.0 @ 1 [..] cxld_unregister: cxl decoder14.0: cxl_region_decode_reset: cxl_region region3: mock_decoder_reset: cxl_port port3: decoder3.0 reset 2) mock_decoder_reset: cxl_port port3: decoder3.0: out of order reset, expected decoder3.1 cxl_endpoint_decoder_release: cxl decoder14.0: [..] cxld_unregister: cxl decoder7.0: 3) cxl_region_decode_reset: cxl_region region3: Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bc3: 0000 [#1] PREEMPT SMP PTI [..] RIP: 0010:to_cxl_port+0x8/0x60 [cxl_core] [..] Call Trace: <TASK> cxl_region_decode_reset+0x69/0x190 [cxl_core] cxl_region_detach+0xe8/0x210 [cxl_core] cxl_decoder_kill_region+0x27/0x40 [cxl_core] cxld_unregister+0x5d/0x60 [cxl_core] At 1) a region has been established with 2 endpoint decoders (7.0 and 14.0). Those endpoints share a common switch-decoder in the topology (3.0). At teardown, 2), decoder14.0 is the first to be removed and hits the "out of order reset case" in the switch decoder. The effect though is that region3 cleanup is aborted leaving it in-tact and referencing decoder14.0. At 3) the second attempt to teardown region3 trips over the stale decoder14.0 object which has long since been deleted. The fix here is to recognize that the CXL specification places no mandate on in-order shutdown of switch-decoders, the driver enforces in-order allocation, and hardware enforces in-order commit. So, rather than fail and leave objects dangling, always remove them. In support of making cxl_region_decode_reset() always succeed, cxl_region_invalidate_memregion() failures are turned into warnings. Crashing the kernel is ok there since system integrity is at risk if caches cannot be managed around physical address mutation events like CXL region destruction. A new device_for_each_child_reverse_from() is added to cleanup port->commit_end after all dependent decoders have been disabled. In other words if decoders are allocated 0->1->2 and disabled 1->2->0 then port->commit_end only decrements from 2 after 2 has been disabled, and it decrements all the way to zero since 1 was disabled previously. Link: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net [1] Cc: stable@vger.kernel.org Fixes: 176baefb2eb5 ("cxl/hdm: Commit decoder state to hardware") Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Zijun Hu <quic_zijuhu@quicinc.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://patch.msgid.link/172964782781.81806.17902885593105284330.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2024-10-25cxl/acpi: Ensure ports ready at cxl_acpi_probe() returnDan Williams
In order to ensure root CXL ports are enabled upon cxl_acpi_probe() when the 'cxl_port' driver is built as a module, arrange for the module to be pre-loaded or built-in. The "Fixes:" but no "Cc: stable" on this patch reflects that the issue is merely by inspection since the bug that triggered the discovery of this potential problem [1] is fixed by other means. However, a stable backport should do no harm. Fixes: 8dd2bc0f8e02 ("cxl/mem: Add the cxl_mem driver") Link: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net [1] Signed-off-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Gregory Price <gourry@gourry.net> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://patch.msgid.link/172964781969.81806.17276352414854540808.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2024-10-25cxl/port: Fix cxl_bus_rescan() vs bus_rescan_devices()Dan Williams
It turns out since its original introduction, pre-2.6.12, bus_rescan_devices() has skipped devices that might be in the process of attaching or detaching from their driver. For CXL this behavior is unwanted and expects that cxl_bus_rescan() is a probe barrier. That behavior is simple enough to achieve with bus_for_each_dev() paired with call to device_attach(), and it is unclear why bus_rescan_devices() took the position of lockless consumption of dev->driver which is racy. The "Fixes:" but no "Cc: stable" on this patch reflects that the issue is merely by inspection since the bug that triggered the discovery of this potential problem [1] is fixed by other means. However, a stable backport should do no harm. Fixes: 8dd2bc0f8e02 ("cxl/mem: Add the cxl_mem driver") Link: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net [1] Signed-off-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Gregory Price <gourry@gourry.net> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://patch.msgid.link/172964781104.81806.4277549800082443769.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2024-10-25cxl/port: Fix CXL port initialization order when the subsystem is built-inDan Williams
When the CXL subsystem is built-in the module init order is determined by Makefile order. That order violates expectations. The expectation is that cxl_acpi and cxl_mem can race to attach. If cxl_acpi wins the race, cxl_mem will find the enabled CXL root ports it needs. If cxl_acpi loses the race it will retrigger cxl_mem to attach via cxl_bus_rescan(). That flow only works if cxl_acpi can assume ports are enabled immediately upon cxl_acpi_probe() return. That in turn can only happen in the CONFIG_CXL_ACPI=y case if the cxl_port driver is registered before cxl_acpi_probe() runs. Fix up the order to prevent initialization failures. Ensure that cxl_port is built-in when cxl_acpi is also built-in, arrange for Makefile order to resolve the subsys_initcall() order of cxl_port and cxl_acpi, and arrange for Makefile order to resolve the device_initcall() (module_init()) order of the remaining objects. As for what contributed to this not being found earlier, the CXL regression environment, cxl_test, builds all CXL functionality as a module to allow to symbol mocking and other dynamic reload tests. As a result there is no regression coverage for the built-in case. Reported-by: Gregory Price <gourry@gourry.net> Closes: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net Tested-by: Gregory Price <gourry@gourry.net> Fixes: 8dd2bc0f8e02 ("cxl/mem: Add the cxl_mem driver") Cc: stable@vger.kernel.org Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Jonathan Cameron <jonathan.cameron@huawei.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Tested-by: Alejandro Lucero <alucerop@amd.com> Reviewed-by: Alejandro Lucero <alucerop@amd.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Link: https://patch.msgid.link/172988474904.476062.7961350937442459266.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2024-10-25cxl/events: Fix Trace DRAM Event RecordShiju Jose
CXL spec rev 3.0 section 8.2.9.2.1.2 defines the DRAM Event Record. Fix decode memory event type field of DRAM Event Record. For e.g. if value is 0x1 it will be reported as an Invalid Address (General Media Event Record - Memory Event Type) instead of Scrub Media ECC Error (DRAM Event Record - Memory Event Type) and so on. Fixes: 2d6c1e6d60ba ("cxl/mem: Trace DRAM Event Record") Signed-off-by: Shiju Jose <shiju.jose@huawei.com> Link: https://patch.msgid.link/20241014143003.1170-1-shiju.jose@huawei.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2024-10-24cxl/core: Return error when cxl_endpoint_gather_bandwidth() handles a ↵Li Zhijian
non-PCI device The function cxl_endpoint_gather_bandwidth() invokes pci_bus_read/write_XXX(), however, not all CXL devices are presently implemented via PCI. It is recognized that the cxl_test has realized a CXL device using a platform device. Calling pci_bus_read/write_XXX() in cxl_test will cause kernel panic: platform cxl_host_bridge.3: host supports CXL (restricted) Oops: general protection fault, probably for non-canonical address 0x3ef17856fcae4fbd: 0000 [#1] PREEMPT SMP PTI Call Trace: <TASK> ? __die_body.cold+0x19/0x27 ? die_addr+0x38/0x60 ? exc_general_protection+0x1f5/0x4b0 ? asm_exc_general_protection+0x22/0x30 ? pci_bus_read_config_word+0x1c/0x60 pcie_capability_read_word+0x93/0xb0 pcie_link_speed_mbps+0x18/0x50 cxl_pci_get_bandwidth+0x18/0x60 [cxl_core] cxl_endpoint_gather_bandwidth.constprop.0+0xf4/0x230 [cxl_core] ? xas_store+0x54/0x660 ? preempt_count_add+0x69/0xa0 ? _raw_spin_lock+0x13/0x40 ? __kmalloc_cache_noprof+0xe7/0x270 cxl_region_shared_upstream_bandwidth_update+0x9c/0x790 [cxl_core] cxl_region_attach+0x520/0x7e0 [cxl_core] store_targetN+0xf2/0x120 [cxl_core] kernfs_fop_write_iter+0x13a/0x1f0 vfs_write+0x23b/0x410 ksys_write+0x53/0xd0 do_syscall_64+0x62/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e And Ying also reported a KASAN error with similar calltrace. Reported-by: Huang, Ying <ying.huang@intel.com> Closes: http://lore.kernel.org/87y12w9vp5.fsf@yhuang6-desk2.ccr.corp.intel.com Fixes: a5ab0de0ebaa ("cxl: Calculate region bandwidth of targets with shared upstream link") Signed-off-by: Li Zhijian <lizhijian@fujitsu.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Huang, Ying <ying.huang@intel.com> Link: https://patch.msgid.link/20241022030054.258942-1-lizhijian@fujitsu.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>
2024-10-02move asm/unaligned.h to linux/unaligned.hAl Viro
asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
2024-09-27Merge tag 'cxl-for-6.12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl Pull compute express link (cxl) updates from Dave Jiang: "Major changes address HDM decoder initialization from DVSEC ranges, refactoring the code related to cxl mailboxes to be independent of the memory devices, and adding support for shared upstream link access_coordinate calculation, as well as a change to remove locking from memory notifier callback. In addition, a number of misc cleanups and refactoring of the code are also included. Address HDM decoder initialization from DVSEC ranges: - Only register non-zero DVSEC ranges - Remove duplicate implementation of waiting for memory_info_valid - Simplify the checking of mem_enabled in cxl_hdm_decode_init() Refactor the code related to cxl mailboxes to be independent of the memory devices: - Move cxl headers in include/linux/ to include/cxl - Move all mailbox related data to 'struct cxl_mailbox' - Refactor mailbox APIs with 'struct cxl_mailbox' as input instead of memory device state Add support for shared upstream link access_coordinate calculation for configurations that have multiple targets under a switch or a root port where the aggregated bandwidth can be greater than the upstream link of the switch/RP upstream link: - Preserve the CDAT access_coordinate from an endpoint - Add the support for shared upstream link access_coordinate calculation - Add documentation to explain how the calculations are done Remove locking from memory notifier callback. Misc cleanups: - Convert devm_cxl_add_root() to return using ERR_CAST() - cxl_test use dev_is_platform() instead of open coding - Remove duplicate include of header core.h in core/cdat.c - use scoped resource management to drop put_device() for cxl_port - Use scoped_guard to drop device_lock() for cxl_port - Refactor __devm_cxl_add_port() to drop gotos - Rename cxl_setup_parent_dport to cxl_dport_init_aer and cxl_dport_map_regs() to cxl_dport_map_ras() - Refactor cxl_dport_init_aer() to be more concise - Remove duplicate host_bridge->native_aer checking in cxl_dport_init_ras_reporting() - Fix comment for cxl_query_cmd()" * tag 'cxl-for-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (21 commits) cxl: Add documentation to explain the shared link bandwidth calculation cxl: Calculate region bandwidth of targets with shared upstream link cxl: Preserve the CDAT access_coordinate for an endpoint cxl: Fix comment regarding cxl_query_cmd() return data cxl: Convert cxl_internal_send_cmd() to use 'struct cxl_mailbox' as input cxl: Move mailbox related bits to the same context cxl: move cxl headers to new include/cxl/ directory cxl/region: Remove lock from memory notifier callback cxl/pci: simplify the check of mem_enabled in cxl_hdm_decode_init() cxl/pci: Check Mem_info_valid bit for each applicable DVSEC cxl/pci: Remove duplicated implementation of waiting for memory_info_valid cxl/pci: Fix to record only non-zero ranges cxl/pci: Remove duplicate host_bridge->native_aer checking cxl/pci: cxl_dport_map_rch_aer() cleanup cxl/pci: Rename cxl_setup_parent_dport() and cxl_dport_map_regs() cxl/port: Refactor __devm_cxl_add_port() to drop goto pattern cxl/port: Use scoped_guard()/guard() to drop device_lock() for cxl_port cxl/port: Use __free() to drop put_device() for cxl_port cxl: Remove duplicate included header file core.h tools/testing/cxl: Use dev_is_platform() ...
2024-09-22cxl: Calculate region bandwidth of targets with shared upstream linkDave Jiang
The current bandwidth calculation aggregates all the targets. This simple method does not take into account where multiple targets sharing under a switch or a root port where the aggregated bandwidth can be greater than the upstream link of the switch. To accurately account for the shared upstream uplink cases, a new update function is introduced by walking from the leaves to the root of the hierarchy and clamp the bandwidth in the process as needed. This process is done when all the targets for a region are present but before the final values are send to the HMAT handling code cached access_coordinate targets. The original perf calculation path was kept to calculate the latency performance data that does not require the shared link consideration. The shared upstream link calculation is done as a second pass when all the endpoints have arrived. Testing is done via qemu with CXL hierarchy. run_qemu[1] is modified to support several CXL hierarchy layouts. The following layouts are tested: HB: Host Bridge RP: Root Port SW: Switch EP: End Point 2 HB 2 RP 2 EP: resulting bandwidth: 624 1 HB 2 RP 2 EP: resulting bandwidth: 624 2 HB 2 RP 2 SW 4 EP: resulting bandwidth: 624 Current testing, perf number from SRAT/HMAT is hacked into the kernel code. However with new QEMU support of Generic Target Port that's incoming, the perf data injection is no longer needed. [1]: https://github.com/pmem/run_qemu Suggested-by: Jonathan Cameron <jonathan.cameron@huawei.com> Link: https://lore.kernel.org/linux-cxl/20240501152503.00002e60@Huawei.com/ Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Link: https://patch.msgid.link/20240904001316.1688225-3-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-22cxl: Preserve the CDAT access_coordinate for an endpointDave Jiang
Keep the access_coordinate from the CDAT tables for region perf calculations. The region perf calculation requires all participating endpoints to have arrived in order to determine if there are limitations of bandwidth data due to shared uplink. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Link: https://patch.msgid.link/20240904001316.1688225-2-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-18cxl: Fix comment regarding cxl_query_cmd() return dataDave Jiang
The code indicates that the min of n_commands and total commands is returned. The comment incorrectly says it's the max(). Correct comment to min(). Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://patch.msgid.link/20240913223216.3234173-1-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-12cxl: Convert cxl_internal_send_cmd() to use 'struct cxl_mailbox' as inputDave Jiang
With the CXL mailbox context split out, cxl_internal_send_cmd() can take 'struct cxl_mailbox' as an input parameter rather than 'struct memdev_dev_state'. Change input parameter for cxl_internal_send_cmd() and fixup all impacted call sites. Reviewed-by: Fan Ni <fan.ni@samsung.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://patch.msgid.link/20240905223711.1990186-4-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-12cxl: Move mailbox related bits to the same contextDave Jiang
Create a new 'struct cxl_mailbox' and move all mailbox related bits to it. This allows isolation of all CXL mailbox data in order to export some of the calls to external kernel callers and avoid exporting of CXL driver specific bits such has device states. The allocation of 'struct cxl_mailbox' is also split out with cxl_mailbox_init() so the mailbox can be created independently. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Alejandro Lucero <alucerop@amd.com> Reviewed-by: Fan Ni <fan.ni@samsung.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://patch.msgid.link/20240905223711.1990186-3-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-09cxl: move cxl headers to new include/cxl/ directoryDave Jiang
Group all cxl related kernel headers into include/cxl/ directory. Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://patch.msgid.link/20240905223711.1990186-2-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-09cxl/region: Remove lock from memory notifier callbackIra Weiny
In testing Dynamic Capacity Device (DCD) support, a lockdep splat revealed an ABBA issue between the memory notifiers and the DCD extent processing code.[0] Changing the lock ordering within DCD proved difficult because regions must be stable while searching for the proper region and then the device lock must be held to properly notify the DAX region driver of memory changes. Dan points out in the thread that notifiers should be able to trust that it is safe to access static data. Region data is static once the device is realized and until it's destruction. Thus it is better to manage the notifiers within the region driver. Remove the need for a lock by ensuring the notifiers are active only during the region's lifetime. Furthermore, remove cxl_region_nid() because resource can't be NULL while the region is stable. Link: https://lore.kernel.org/all/66b4cf539a79b_a36e829416@iweiny-mobl.notmuch/ [0] Cc: Ying Huang <ying.huang@intel.com> Suggested-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ying Huang <ying.huang@intel.com> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Link: https://patch.msgid.link/20240904-fix-notifiers-v3-1-576b4e950266@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-09cxl/pci: simplify the check of mem_enabled in cxl_hdm_decode_init()Yanfei Xu
Cases can be divided into two categories which are DVSEC range enabled and not enabled when HDM decoders exist but is not enabled. To avoid checking info->mem_enabled, which indicates the enablement of DVSEC range, every time, we can check !info->mem_enabled once in advance. This simplification can make the code clearer. No functional change intended. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Yanfei Xu <yanfei.xu@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://patch.msgid.link/20240828084231.1378789-5-yanfei.xu@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-09cxl/pci: Check Mem_info_valid bit for each applicable DVSECYanfei Xu
In theory a device might set the mem_info_valid bit for a first range after it is ready but before as second range has reached that state. Therefore, the correct approach is to check the Mem_info_valid bit for each applicable DVSEC range against HDM_COUNT, rather than only for the DVSEC range 1. Consequently, let's move the check into the "for loop" that handles each DVSEC range. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Yanfei Xu <yanfei.xu@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://patch.msgid.link/20240828084231.1378789-4-yanfei.xu@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-09cxl/pci: Remove duplicated implementation of waiting for memory_info_validYanfei Xu
commit ce17ad0d5498 ("cxl: Wait Memory_Info_Valid before access memory related info") added another implementation, which is cxl_dvsec_mem_range_valid(), of waiting for memory_info_valid without realizing it duplicated wait_for_valid(). Remove wait_for_valid() and retain cxl_dvsec_mem_range_valid() as the former is hardcoded to check only the Memory_Info_Valid bit of DVSEC range 1, while the latter allows for selection between DVSEC range 1 or 2 via parameter. Suggested-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Yanfei Xu <yanfei.xu@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://patch.msgid.link/20240828084231.1378789-3-yanfei.xu@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-09cxl/pci: Fix to record only non-zero rangesYanfei Xu
The function cxl_dvsec_rr_decode() retrieves and records DVSEC ranges into info->dvsec_range[], regardless of whether it is non-zero range, and the variable info->ranges indicates the number of non-zero ranges. However, in cxl_hdm_decode_init(), the validation for info->dvsec_range[] occurs in a for loop that iterates based on info->ranges. It may result in zero range to be validated but non-zero range not be validated, in turn, the number of allowed ranges is to be 0. Address it by only record non-zero ranges. This fix is not urgent as it requires a configuration that zeroes out the first dvsec range while populating the second. This has not been observed, but it is theoretically possible. If this gets picked up for -stable, no harm done, but there is no urgency to backport. Fixes: 560f78559006 ("cxl/pci: Retrieve CXL DVSEC memory info") Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Yanfei Xu <yanfei.xu@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://patch.msgid.link/20240828084231.1378789-2-yanfei.xu@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-03mm: make range-to-target_node lookup facility a part of numa_memblksMike Rapoport (Microsoft)
The x86 implementation of range-to-target_node lookup (i.e. phys_to_target_node() and memory_add_physaddr_to_nid()) relies on numa_memblks. Since numa_memblks are now part of the generic code, move these functions from x86 to mm/numa_memblks.c and select CONFIG_NUMA_KEEP_MEMINFO when CONFIG_NUMA_MEMBLKS=y for dax and cxl. [rppt@kernel.org: fix build] Link: https://lkml.kernel.org/r/ZtVfSt_zloPdDqVB@kernel.org Link: https://lkml.kernel.org/r/20240807064110.1003856-26-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: Zi Yan <ziy@nvidia.com> # for x86_64 and arm64 Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> [arm64 + CXL via QEMU] Reviewed-by: Dan Williams <dan.j.williams@intel.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: David S. Miller <davem@davemloft.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Rob Herring (Arm) <robh@kernel.org> Cc: Samuel Holland <samuel.holland@sifive.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-03cxl/pci: Remove duplicate host_bridge->native_aer checkingLi Ming
cxl_dport_init_ras_reporting() already checks host_bridge->native_aer before invoking cxl_disable_rch_root_ints(), so cxl_disable_rch_root_ints() does not need to check it again. Signed-off-by: Li Ming <ming4.li@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/20240830061308.2327065-3-ming4.li@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-03cxl/pci: cxl_dport_map_rch_aer() cleanupLi Ming
cxl_dport_map_ras() is used to map CXL RAS capability, the RCH AER capability should not be mapped in the function but should mapped in cxl_dport_init_ras_reporting(). Moving cxl_dport_map_ras() out of cxl_dport_map_ras() and into cxl_dport_init_ras_reporting(). In cxl_dport_init_ras_reporting(), the AER capability position in RCRB will be located but the position is only used in cxl_dport_map_rch_aer(), getting the position in cxl_dport_map_rch_aer() rather than cxl_dport_init_ras_reporting() is more reasonable and makes the code clearer. Besides, some local variables in cxl_dport_map_rch_aer() are unnecessary, remove them to make the function more concise. Signed-off-by: Li Ming <ming4.li@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/20240830061308.2327065-2-ming4.li@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-03cxl/pci: Rename cxl_setup_parent_dport() and cxl_dport_map_regs()Li Ming
The name of cxl_setup_parent_dport() function is not clear, the function is used to initialize AER and RAS capabilities on a dport, therefore, rename the function to cxl_dport_init_ras_reporting(), it is easier for user to understand what the function does. Besides, adjust the order of the function parameters, the subject of cxl_dport_init_ras_reporting() is a cxl dport, so a struct cxl_dport as the first parameter of the function should be better. cxl_dport_map_regs() is used to map CXL RAS capability on a cxl dport, using cxl_dport_map_ras() as the function name. Signed-off-by: Li Ming <ming4.li@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/20240830061308.2327065-1-ming4.li@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-03cxl/port: Refactor __devm_cxl_add_port() to drop goto patternLi Ming
In __devm_cxl_add_port(), there is a 'goto' to call put_device() for the error cases between device_initialize() and device_add() to dereference the 'struct device' of a new cxl_port. The 'goto' pattern in the case can be removed by refactoring. Introducing a new function called cxl_port_add() which is used to add the 'struct device' of a new cxl_port to device hierarchy, moving the functions needing the help of the 'goto' into cxl_port_add(), and using a scoped-based resource management __free() to drop the open coded put_device() and the 'goto' for the error cases. Suggested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Li Ming <ming4.li@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huwaei.com> Link: https://patch.msgid.link/20240830013138.2256244-3-ming4.li@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-03cxl/port: Use scoped_guard()/guard() to drop device_lock() for cxl_portLi Ming
A device_lock() and device_unlock() pair can be replaced by a cleanup helper scoped_guard() or guard(), that can enhance code readability. In CXL subsystem, still use device_lock() and device_unlock() pairs for cxl port resource protection, most of them can be replaced by a scoped_guard() or a guard() simply. Suggested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Li Ming <ming4.li@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/20240830013138.2256244-2-ming4.li@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-03cxl/port: Use __free() to drop put_device() for cxl_portLi Ming
Using scope-based resource management __free() marco with a new helper called put_cxl_port() to drop open coded the put_device() used to dereference the 'struct device' in cxl_port. Suggested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Li Ming <ming4.li@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/20240830013138.2256244-1-ming4.li@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-03cxl: Remove duplicate included header file core.hHongbo Li
The header file core.h is included twice. Remove the last one. The compilation test has passed. Signed-off-by: Hongbo Li <lihongbo22@huawei.com> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://patch.msgid.link/20240830080016.3542184-1-lihongbo22@huawei.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-03cxl/port: Convert to use ERR_CAST()Yuesong Li
Use ERR_CAST() as it is designed for casting an error pointer to another type. This macro utilizes the __force and __must_check modifiers, which instruct the compiler to verify for errors at the locations where it is employed. Signed-off-by: Yuesong Li <liyuesong@vivo.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://patch.msgid.link/20240829125235.3266865-1-liyuesong@vivo.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-08-09cxl/pci: Get AER capability address from RCRB only for RCH dportLi Ming
cxl_setup_parent_dport() needs to get RCH dport AER capability address from RCRB to disable AER interrupt. The function does not check if dport is RCH dport, it will get a wrong pci_host_bridge structure by dport_dev in VH case because dport_dev points to a pci device(RP or switch DSP) rather than a pci host bridge device. Fixes: f05fd10d138d ("cxl/pci: Add RCH downstream port AER register discovery") Signed-off-by: Li Ming <ming4.li@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Tested-by: Ira Weiny <ira.weiny@intel.com> Tested-by: Alison Schofield <alison.schofield@intel.com> Link: https://patch.msgid.link/20240809082750.3015641-2-ming4.li@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-07-28Merge tag 'cxl-for-6.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl Pull CXL updates from Dave Jiang: "Core: - A CXL maturity map has been added to the documentation to detail the current state of CXL enabling. It provides the status of the current state of various CXL features to inform current and future contributors of where things are and which areas need contribution. - A notifier handler has been added in order for a newly created CXL memory region to trigger the abstract distance metrics calculation. This should bring parity for CXL memory to the same level vs hotplugged DRAM for NUMA abstract distance calculation. The abstract distance reflects relative performance used for memory tiering handling. - An addition for XOR math has been added to address the CXL DPA to SPA translation. CXL address translation did not support address interleave math with XOR prior to this change. Fixes: - Fix to address race condition in the CXL memory hotplug notifier - Add missing MODULE_DESCRIPTION() for CXL modules - Fix incorrect vendor debug UUID define Misc: - A warning has been added to inform users of an unsupported configuration when mixing CXL VH and RCH/RCD hierarchies - The ENXIO error code has been replaced with EBUSY for inject poison limit reached via debugfs and cxl-test support - Moving the PCI config read in cxl_dvsec_rr_decode() to avoid unnecessary PCI config reads - A refactor to a common struct for DRAM and general media CXL events" * tag 'cxl-for-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: cxl/core/pci: Move reading of control register to immediately before usage cxl: Remove defunct code calculating host bridge target positions cxl/region: Verify target positions using the ordered target list cxl: Restore XOR'd position bits during address translation cxl/core: Fold cxl_trace_hpa() into cxl_dpa_to_hpa() cxl/test: Replace ENXIO with EBUSY for inject poison limit reached cxl/memdev: Replace ENXIO with EBUSY for inject poison limit reached cxl/acpi: Warn on mixed CXL VH and RCH/RCD Hierarchy cxl/core: Fix incorrect vendor debug UUID define Documentation: CXL Maturity Map cxl/region: Simplify cxl_region_nid() cxl/region: Support to calculate memory tier abstract distance cxl/region: Fix a race condition in memory hotplug notifier cxl: add missing MODULE_DESCRIPTION() macros cxl/events: Use a common struct for DRAM and General Media events
2024-07-25Merge tag 'driver-core-6.11-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the big set of driver core changes for 6.11-rc1. Lots of stuff in here, with not a huge diffstat, but apis are evolving which required lots of files to be touched. Highlights of the changes in here are: - platform remove callback api final fixups (Uwe took many releases to get here, finally!) - Rust bindings for basic firmware apis and initial driver-core interactions. It's not all that useful for a "write a whole driver in rust" type of thing, but the firmware bindings do help out the phy rust drivers, and the driver core bindings give a solid base on which others can start their work. There is still a long way to go here before we have a multitude of rust drivers being added, but it's a great first step. - driver core const api changes. This reached across all bus types, and there are some fix-ups for some not-common bus types that linux-next and 0-day testing shook out. This work is being done to help make the rust bindings more safe, as well as the C code, moving toward the end-goal of allowing us to put driver structures into read-only memory. We aren't there yet, but are getting closer. - minor devres cleanups and fixes found by code inspection - arch_topology minor changes - other minor driver core cleanups All of these have been in linux-next for a very long time with no reported problems" * tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits) ARM: sa1100: make match function take a const pointer sysfs/cpu: Make crash_hotplug attribute world-readable dio: Have dio_bus_match() callback take a const * zorro: make match function take a const pointer driver core: module: make module_[add|remove]_driver take a const * driver core: make driver_find_device() take a const * driver core: make driver_[create|remove]_file take a const * firmware_loader: fix soundness issue in `request_internal` firmware_loader: annotate doctests as `no_run` devres: Correct code style for functions that return a pointer type devres: Initialize an uninitialized struct member devres: Fix memory leakage caused by driver API devm_free_percpu() devres: Fix devm_krealloc() wasting memory driver core: platform: Switch to use kmemdup_array() driver core: have match() callback in struct bus_type take a const * MAINTAINERS: add Rust device abstractions to DRIVER CORE device: rust: improve safety comments MAINTAINERS: add Danilo as FIRMWARE LOADER maintainer MAINTAINERS: add Rust FW abstractions to FIRMWARE LOADER firmware: rust: improve safety comments ...
2024-07-17cxl/core/pci: Move reading of control register to immediately before usageForyun Ma
Relocate the reading of the DVSEC control register to immediately before usage and avoid unnecessary PCI config access from the read if DVSEC capability check, hdm_count check, or device validity check results in failure. Signed-off-by: Foryun Ma <foryun.ma@jaguarmicro.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://patch.msgid.link/20240604032151.655-1-foryun.ma@jaguarmicro.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-07-11Merge branch 'for-6.11/xor_fixes' into cxl-for-nextDave Jiang
Series to fix XOR math for DPA to SPA translation - Refactor and fold cxl_trace_hpa() into cxl_dpa_to_hpa() - Complete DPA->HPA->SPA translation and correct XOR translation issue - Add new method to verify a CXL target position - Remove old method of CXL target position verifiation
2024-07-11cxl: Remove defunct code calculating host bridge target positionsAlison Schofield
The CXL Spec 3.1 Table 9-22 requires that the BIOS populate the CFMWS target list in interleave target order. This means the calculations the CXL driver added to determine positions when XOR math is in use, along with the entire XOR vs Modulo call back setup is not needed. A prior patch added a common method to verify positions. Remove the now unused code related to the cxl_calc_hb_fn. Signed-off-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/2e2c32a2d0f1007e920b58712d15edad2e48d857.1719980933.git.alison.schofield@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-07-11cxl/region: Verify target positions using the ordered target listAlison Schofield
When a root decoder is configured the interleave target list is read from the BIOS populated CFMWS structure. Per the CXL spec 3.1 Table 9-22 the target list is in interleave order. The CXL driver populates its decoder target list in the same order and stores it in 'struct cxl_switch_decoder' field "@target: active ordered target list in current decoder configuration" Given the promise of an ordered list, the driver can stop duplicating the work of BIOS and simply check target positions against the ordered list during region configuration. The simplified check against the ordered list is presented here. A follow-on patch will remove the unused code. For Modulo arithmetic this is not a fix, only a simplification. For XOR arithmetic this is a fix for HB IW of 3,6,12. Fixes: f9db85bfec0d ("cxl/acpi: Support CXL XOR Interleave Math (CXIMS)") Signed-off-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/35d08d3aba08fee0f9b86ab1cef0c25116ca8a55.1719980933.git.alison.schofield@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-07-11cxl: Restore XOR'd position bits during address translationAlison Schofield
When a device reports a DPA in events like poison, general_media, and dram, the driver translates that DPA back to an HPA. Presently, the CXL driver translation only considers the Modulo position and will report the wrong HPA for XOR configured root decoders. Add a helper function that restores the XOR'd bits during DPA->HPA address translation. Plumb a root decoder callback to the new helper when XOR interleave arithmetic is in use. For Modulo arithmetic, just let the callback be NULL - as in no extra work required. Upon completion of a DPA->HPA translation a couple of checks are performed on the result. One simply confirms that the calculated HPA is within the address range of the region. That test is useful for both Modulo and XOR interleave arithmetic decodes. A second check confirms that the HPA is within an expected chunk based on the endpoints position in the region and the region granularity. An XOR decode disrupts the Modulo pattern making the chunk check useless. To align the checks with the proper decode, pull the region range check inline and use the helper to do the chunk check for Modulo decodes only. A cxl-test unit test is posted for upstream review here: https://lore.kernel.org/20240624210644.495563-1-alison.schofield@intel.com/ Fixes: 28a3ae4ff66c ("cxl/trace: Add an HPA to cxl_poison trace events") Signed-off-by: Alison Schofield <alison.schofield@intel.com> Tested-by: Diego Garcia Rodriguez <diego.garcia.rodriguez@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Link: https://patch.msgid.link/1a1ac880d9f889bd6384e657e810431b9a0a72e5.1719980933.git.alison.schofield@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-07-11cxl/core: Fold cxl_trace_hpa() into cxl_dpa_to_hpa()Alison Schofield
Although cxl_trace_hpa() is used to populate TRACE EVENTs with HPA addresses the work it performs is a DPA to HPA translation not a trace. Tidy up this naming by moving the minimal work done in cxl_trace_hpa() into cxl_dpa_to_hpa() and use cxl_dpa_to_hpa() for trace event callbacks. Suggested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Robert Richter <rrichter@amd.com> Link: https://patch.msgid.link/452a9b0c525b774c72d9d5851515ffa928750132.1719980933.git.alison.schofield@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-07-10cxl/memdev: Replace ENXIO with EBUSY for inject poison limit reachedAlison Schofield
The CXL driver provides a debugfs interface offering users the ability to inject and clear poison to a memdev. Once a user has injected up to the devices limit further injection requests fail with ENXIO until a clear poison is issued. Users may not have device specs in hand or may want to intentionally hit the limit and then clear. Replace the usual ENXIO return status with EBUSY so users can recognize this failure. Signed-off-by: Alison Schofield <alison.schofield@intel.com> Tested-by: Xingtao Yao <yaoxt.fnst@fujitsu.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Link: https://patch.msgid.link/825bd4c67fb55a4373c4182d999ad49d4e6b4fe7.1720316188.git.alison.schofield@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-07-10cxl/acpi: Warn on mixed CXL VH and RCH/RCD HierarchyFabio M. De Francesco
Each Host Bridge instance has a corresponding CXL Host Bridge Structure (CHBS) ACPI table that identifies its capabilities. CHBS tables can be two types (CXL 3.1 Table 9-21): The PCIe Root Complex Register Block (RCRB) and CXL Host Bridge Component Registers (CHBCR). If a Host Bridge is attached to a device that is operating in Restricted CXL Device Mode (RCD), BIOS publishes an RCRB with the base address of registers that describe its capabilities (CXL 3.1 sec. 9.11). Instead, the new (CXL 2.0+) Component registers can only be accessed by means of a base address published with a CHBCR (CXL 3.1 sec. 9.12). If an eRCD (a device that forces the host-bridge into CXL 1.1 Restricted CXL Host mode) is attached to a CXL 2.0+ Host-Bridge, the current CXL specification does not define a mechanism for finding CXL-2.0-only root-port component registers like HDM decoders and Extended Security capability. An algorithm to locate a CHBCR associated with an RCRB, would be too invasive to land without some concrete motivation. Therefore, just print a message to inform of unsupported config. Count how many different CHBS "Version" types are detected by cxl_get_chbs_iter(). Then make cxl_get_chbs() print a warning if that sum is greater than 1. Tested-by: Alison Schofield <alison.schofield@intel.com> Signed-off-by: Fabio M. De Francesco <fabio.m.de.francesco@linux.intel.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://patch.msgid.link/20240628175535.272472-1-fabio.m.de.francesco@linux.intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-07-10cxl/core: Fix incorrect vendor debug UUID definepeng guo
When user send a mbox command whose opcode is CXL_MBOX_OP_CLEAR_LOG and the in_payload is normal vendor debug log UUID according to the CXL specification cxl_payload_from_user_allowed() will return false unexpectedly, Sending mbox cmd operation fails and the kernel log will print: Clear Log: input payload not allowed. All CXL devices that support a debug log shall support the Vendor Debug Log to allow the log to be accessed through a common host driver, for any device, all versions of the CXL specification define the same value with Log Identifier of: 5e1819d9-11a9-400c-811f-d60719403d86 Refer to CXL spec r3.1 Table 8-71 Fix the definition value of DEFINE_CXL_VENDOR_DEBUG_UUID to match the CXL specification. Fixes: 472b1ce6e9d6 ("cxl/mem: Enable commands via CEL") Signed-off-by: peng guo <engguopeng@buaa.edu.cn> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://patch.msgid.link/20240710023112.8063-1-engguopeng@buaa.edu.cn Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-07-03driver core: have match() callback in struct bus_type take a const *Greg Kroah-Hartman
In the match() callback, the struct device_driver * should not be changed, so change the function callback to be a const *. This is one step of many towards making the driver core safe to have struct device_driver in read-only memory. Because the match() callback is in all busses, all busses are modified to handle this properly. This does entail switching some container_of() calls to container_of_const() to properly handle the constant *. For some busses, like PCI and USB and HV, the const * is cast away in the match callback as those busses do want to modify those structures at this point in time (they have a local lock in the driver structure.) That will have to be changed in the future if they wish to have their struct device * in read-only-memory. Cc: Rafael J. Wysocki <rafael@kernel.org> Reviewed-by: Alex Elder <elder@kernel.org> Acked-by: Sumit Garg <sumit.garg@linaro.org> Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-02cxl/region: Simplify cxl_region_nid()Huang Ying
The node ID of the region can be gotten via resource start address directly. This simplifies the implementation of cxl_region_nid(). Signed-off-by: Huang Ying <ying.huang@intel.com> Suggested-by: Alison Schofield <alison.schofield@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Bharata B Rao <bharata@amd.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/20240618084639.1419629-4-ying.huang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-07-02cxl/region: Support to calculate memory tier abstract distanceHuang Ying
An abstract distance value must be assigned by the driver that makes the memory available to the system. It reflects relative performance and is used to place memory nodes backed by CXL regions in the appropriate memory tiers allowing promotion/demotion within the existing memory tiering mechanism. The abstract distance is calculated based on the memory access latency and bandwidth of CXL regions. Signed-off-by: Huang, Ying <ying.huang@intel.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Bharata B Rao <bharata@amd.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/20240618084639.1419629-3-ying.huang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-07-02cxl/region: Fix a race condition in memory hotplug notifierHuang Ying
In the memory hotplug notifier function of the CXL region, cxl_region_perf_attrs_callback(), the node ID is obtained by checking the host address range of the region. However, the address range information is not available when the region is registered in devm_cxl_add_region(). Additionally, this information may be removed or added under the protection of cxl_region_rwsem during runtime. If the memory notifier is called for nodes other than that backed by the region, a race condition may occur, potentially leading to a NULL dereference or an invalid address range. The race condition is addressed by checking the availability of the address range information under the protection of cxl_region_rwsem. To enhance code readability and use guard(), the relevant code has been moved into a newly added function: cxl_region_nid(). Fixes: 067353a46d8c ("cxl/region: Add memory hotplug notifier for cxl region") Signed-off-by: Huang, Ying <ying.huang@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Bharata B Rao <bharata@amd.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/20240618084639.1419629-2-ying.huang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-07-02cxl: add missing MODULE_DESCRIPTION() macrosJeff Johnson
make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/cxl/core/cxl_core.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/cxl/cxl_pci.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/cxl/cxl_mem.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/cxl/cxl_acpi.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/cxl/cxl_pmem.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/cxl/cxl_port.o Add the missing invocations of the MODULE_DESCRIPTION() macro. Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/20240607-md-drivers-cxl-v2-1-0c61d95ee7a7@quicinc.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-07-02cxl/events: Use a common struct for DRAM and General Media eventsFabio M. De Francesco
cxl_event_common was an unfortunate naming choice and caused confusion with the existing Common Event Record. Furthermore, its fields didn't map all the common information between DRAM and General Media Events. Remove cxl_event_common and introduce cxl_event_media_hdr to record common information between DRAM and General Media events. cxl_event_media_hdr, which is embedded in both cxl_event_gen_media and cxl_event_dram, leverages the commonalities between the two events to simplify their respective handling. Suggested-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Fabio M. De Francesco <fabio.m.de.francesco@linux.intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/20240607144423.48681-1-fabio.m.de.francesco@linux.intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-06-25cxl: documentation: add missing files to cxl driver-apiYao Xingtao
Add the missing files into cxl driver api and fix the compile warning. Suggested-by: Dan Williams <dan.j.williams@intel.com> Suggested-by: Alison Schofield <alison.schofield@intel.com> Signed-off-by: Yao Xingtao <yaoxt.fnst@fujitsu.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/20240614084755.59503-3-yaoxt.fnst@fujitsu.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-06-25cxl/region: check interleave capabilityYao Xingtao
Since interleave capability is not verified, if the interleave capability of a target does not match the region need, committing decoder should have failed at the device end. In order to checkout this error as quickly as possible, driver needs to check the interleave capability of target during attaching it to region. Per CXL specification r3.1(8.2.4.20.1 CXL HDM Decoder Capability Register), bits 11 and 12 indicate the capability to establish interleaving in 3, 6, 12 and 16 ways. If these bits are not set, the target cannot be attached to a region utilizing such interleave ways. Additionally, bits 8 and 9 represent the capability of the bits used for interleaving in the address, Linux tracks this in the cxl_port interleave_mask. Per CXL specification r3.1(8.2.4.20.13 Decoder Protection): eIW means encoded Interleave Ways. eIG means encoded Interleave Granularity. in HPA: if eIW is 0 or 8 (interleave ways: 1, 3), all the bits of HPA are used, the interleave bits are none, the following check is ignored. if eIW is less than 8 (interleave ways: 2, 4, 8, 16), the interleave bits start at bit position eIG + 8 and end at eIG + eIW + 8 - 1. if eIW is greater than 8 (interleave ways: 6, 12), the interleave bits start at bit position eIG + 8 and end at eIG + eIW - 1. if the interleave mask is insufficient to cover the required interleave bits, the target cannot be attached to the region. Fixes: 384e624bb211 ("cxl/region: Attach endpoint decoders") Signed-off-by: Yao Xingtao <yaoxt.fnst@fujitsu.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/20240614084755.59503-2-yaoxt.fnst@fujitsu.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-06-25cxl/region: Avoid null pointer dereference in region lookupAlison Schofield
cxl_dpa_to_region() looks up a region based on a memdev and DPA. It wrongly assumes an endpoint found mapping the DPA is also of a fully assembled region. When not true it leads to a null pointer dereference looking up the region name. This appears during testing of region lookup after a failure to assemble a BIOS defined region or if the lookup raced with the assembly of the BIOS defined region. Failure to clean up BIOS defined regions that fail assembly is an issue in itself and a fix to that problem will alleviate some of the impact. It will not alleviate the race condition so let's harden this path. The behavior change is that the kernel oops due to a null pointer dereference is replaced with a dev_dbg() message noting that an endpoint was mapped. Additional comments are added so that future users of this function can more clearly understand what it provides. Fixes: 0a105ab28a4d ("cxl/memdev: Warn of poison inject or clear to a mapped region") Signed-off-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://patch.msgid.link/20240604003609.202682-1-alison.schofield@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>