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path: root/drivers/cxl/core/cdat.c
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2024-12-02module: Convert symbol namespace to string literalPeter Zijlstra
Clean up the existing export namespace code along the same lines of commit 33def8498fdd ("treewide: Convert macro and uses of __section(foo) to __section("foo")") and for the same reason, it is not desired for the namespace argument to be a macro expansion itself. Scripted using git grep -l -e MODULE_IMPORT_NS -e EXPORT_SYMBOL_NS | while read file; do awk -i inplace ' /^#define EXPORT_SYMBOL_NS/ { gsub(/__stringify\(ns\)/, "ns"); print; next; } /^#define MODULE_IMPORT_NS/ { gsub(/__stringify\(ns\)/, "ns"); print; next; } /MODULE_IMPORT_NS/ { $0 = gensub(/MODULE_IMPORT_NS\(([^)]*)\)/, "MODULE_IMPORT_NS(\"\\1\")", "g"); } /EXPORT_SYMBOL_NS/ { if ($0 ~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+),/) { if ($0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)\)/ && $0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(\)/ && $0 !~ /^my/) { getline line; gsub(/[[:space:]]*\\$/, ""); gsub(/[[:space:]]/, "", line); $0 = $0 " " line; } $0 = gensub(/(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)\)/, "\\1(\\2, \"\\3\")", "g"); } } { print }' $file; done Requested-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://mail.google.com/mail/u/2/#inbox/FMfcgzQXKWgMmjdFwwdsfgxzKpVHWPlc Acked-by: Greg KH <gregkh@linuxfoundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-11-22Merge tag 'cxl-for-6.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl Pull cxl updates from Dave Jiang: - Constify range_contains() input parameters to prevent changes - Add support for displaying RCD capabilities in sysfs to support lspci for CXL device - Downgrade warning message to debug in cxl_probe_component_regs() - Add support for adding a printf specifier '%pra' to emit 'struct range' content: - Add sanity tests for 'struct resource' - Add documentation for special case - Add %pra for 'struct range' - Add %pra usage in CXL code - Add preparation code for DCD support: - Add range_overlaps() - Add CDAT DSMAS table shared and read only flag in ACPICA - Add documentation to 'struct dev_dax_range' - Delay event buffer allocation in CXL PCI code until needed - Use guard() in cxl_dpa_set_mode() - Refactor create region code to consolidate common code * tag 'cxl-for-6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: cxl/region: Refactor common create region code cxl/hdm: Use guard() in cxl_dpa_set_mode() cxl/pci: Delay event buffer allocation dax: Document struct dev_dax_range ACPI/CDAT: Add CDAT/DSMAS shared and read only flag values range: Add range_overlaps() cxl/cdat: Use %pra for dpa range outputs printf: Add print format (%pra) for struct range Documentation/printf: struct resource add start == end special case test printf: Add very basic struct resource tests cxl: downgrade a warning message to debug level in cxl_probe_component_regs() cxl/pci: Add sysfs attribute for CXL 1.1 device link status cxl/core/regs: Add rcd_pcie_cap initialization kernel/range: Const-ify range_contains parameters
2024-10-28cxl/cdat: Use %pra for dpa range outputsIra Weiny
Now that there is a printf specifier for struct range use it to enhance the debug output of CDAT data. Reviewed-by: Alison Schofield <alison.schofield@intel.com> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Fan Ni <fan.ni@samsung.com> Link: https://patch.msgid.link/20241025-cxl-pra-v2-4-123a825daba2@intel.com Signed-off-by: Dave Jiang <dave.jiang@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>
2024-09-22cxl: 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>
2024-09-03cxl: 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>
2024-04-08cxl: Consolidate dport access_coordinate ->hb_coord and ->sw_coord into ->coordDave Jiang
The driver stores access_coordinate for host bridge in ->hb_coord and switch CDAT access_coordinate in ->sw_coord. Since neither of these access_coordinate clobber each other, the variable name can be consolidated into ->coord to simplify the code. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Link: https://lore.kernel.org/r/20240403154844.3403859-5-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-04-08cxl: Fix incorrect region perf data calculationDave Jiang
Current math in cxl_region_perf_data_calculate divides the latency by 1000 every time the function gets called. This causes the region latency to be divided by 1000 per memory device and the math is incorrect. This is user visible as the latency access_coordinate exposed via sysfs will show incorrect latency data. Normalize values from CDAT to nanoseconds. Adjust sub-nanoseconds latency to at least 1. Remove adjustment of perf numbers from the generic target since hmat handling code has already normalized those numbers. Now all computation and stored numbers should be in nanoseconds. cxl_hb_get_perf_coordinates() is removed and HB coords are calculated in the port access_coordinate calculation path since it no longer need to be treated special. Fixes: 3d9f4a197230 ("cxl/region: Calculate performance data for a region") Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Link: https://lore.kernel.org/r/20240403154844.3403859-4-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-03-13Merge branch 'for-6.9/cxl-fixes' into for-6.9/cxlDan Williams
Pick up a parsing fix for the CDAT SSLBIS structure for v6.9.
2024-03-13Merge branch 'for-6.9/cxl-qos' into for-6.9/cxlDan Williams
Pick up support for CXL "HMEM reporting" for v6.9, i.e. build an HMAT from CXL CDAT and PCIe switch information.
2024-03-13lib/firmware_table: Provide buffer length argument to cdat_table_parse()Robert Richter
There exist card implementations with a CDAT table using a fixed size buffer, but with entries filled in that do not fill the whole table length size. Then, the last entry in the CDAT table may not mark the end of the CDAT table buffer specified by the length field in the CDAT header. It can be shorter with trailing unused (zero'ed) data. The actual table length is determined while reading all CDAT entries of the table with DOE. If the table is greater than expected (containing zero'ed trailing data), the CDAT parser fails with: [ 48.691717] Malformed DSMAS table length: (24:0) [ 48.702084] [CDAT:0x00] Invalid zero length [ 48.711460] cxl_port endpoint1: Failed to parse CDAT: -22 In addition, a check of the table buffer length is missing to prevent an out-of-bound access then parsing the CDAT table. Hardening code against device returning borked table. Fix that by providing an optional buffer length argument to acpi_parse_entries_array() that can be used by cdat_table_parse() to propagate the buffer size down to its users to check the buffer length. This also prevents a possible out-of-bound access mentioned. Add a check to warn about a malformed CDAT table length. Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Len Brown <lenb@kernel.org> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Robert Richter <rrichter@amd.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/ZdEnopFO0Tl3t2O1@rric.localdomain Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-03-12cxl: Fix the incorrect assignment of SSLBIS entry pointer initial locationDave Jiang
The 'entry' pointer in cdat_sslbis_handler() is set to header + sizeof(common header). However, the math missed the addition of the SSLBIS main header. It should be header + sizeof(common header) + sizeof(*sslbis). Use a defined struct for all the SSLBIS parts in order to avoid pointer math errors. The bug causes incorrect parsing of the SSLBIS table and introduces incorrect performance values to the access_coordinates during the CXL access_coordinate calculation path if there are CXL switches present in the topology. The issue was found during testing of new code being added to add additional checks for invalid CDAT values during CXL access_coordinate calculation. The testing was done on qemu with a CXL topology including a CXL switch. Fixes: 80aa780dda20 ("cxl: Add callback to parse the SSLBIS subtable from CDAT") Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Fan Ni <fan.ni@samsung.com> Link: https://lore.kernel.org/r/20240301210948.1298075-1-dave.jiang@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-03-12cxl/region: Deal with numa nodes not enumerated by SRATDave Jiang
For the numa nodes that are not created by SRAT, no memory_target is allocated and is not managed by the HMAT_REPORTING code. Therefore hmat_callback() memory hotplug notifier will exit early on those NUMA nodes. The CXL memory hotplug notifier will need to call node_set_perf_attrs() directly in order to setup the access sysfs attributes. In acpi_numa_init(), the last proximity domain (pxm) id created by SRAT is stored. Add a helper function acpi_node_backed_by_real_pxm() in order to check if a NUMA node id is defined by SRAT or created by CFMWS. node_set_perf_attrs() symbol is exported to allow update of perf attribs for a node. The sysfs path of /sys/devices/system/node/nodeX/access0/initiators/* is created by node_set_perf_attrs() for the various attributes where nodeX is matched to the NUMA node of the CXL region. Cc: Rafael J. Wysocki <rafael@kernel.org> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240308220055.2172956-13-dave.jiang@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-03-12cxl/region: Add memory hotplug notifier for cxl regionDave Jiang
When the CXL region is formed, the driver computes the performance data for the region. However this data is not available at the node data collection that has been populated by the HMAT during kernel initialization. Add a memory hotplug notifier to update the access coordinates to the 'struct memory_target' context kept by the HMAT_REPORTING code. Add CXL_CALLBACK_PRI for a memory hotplug callback priority. Set the priority number to be called before HMAT_CALLBACK_PRI. The CXL update must happen before hmat_callback(). A new HMAT_REPORTING helper hmat_update_target_coordinates() is added in order to allow CXL to update the memory_target access coordinates. A new ext_updated member is added to the memory_target to indicate that the access coordinates within the memory_target has been updated by an external agent such as CXL. This prevents data being overwritten by the hmat_update_target_attrs() triggered by hmat_callback(). Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Rafael J. Wysocki <rafael@kernel.org> Reviewed-by: Huang, Ying <ying.huang@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240308220055.2172956-12-dave.jiang@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-03-12cxl/region: Calculate performance data for a regionDave Jiang
Calculate and store the performance data for a CXL region. Find the worst read and write latency for all the included ranges from each of the devices that attributes to the region and designate that as the latency data. Sum all the read and write bandwidth data for each of the device region and that is the total bandwidth for the region. The perf list is expected to be constructed before the endpoint decoders are registered and thus there should be no early reading of the entries from the region assemble action. The calling of the region qos calculate function is under the protection of cxl_dpa_rwsem and will ensure that all DPA associated work has completed. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240308220055.2172956-10-dave.jiang@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-03-12cxl: Move QoS class to be calculated from the nearest CPUDave Jiang
Retrieve the qos_class (QTG ID) using the access coordinates from the nearest CPU rather than the nearst initiator that may not be a CPU. This may be the more appropriate number that applications care about. For most cases, access0 and access1 have the same values. Link: https://lore.kernel.org/linux-cxl/20240112113023.00006c50@Huawei.com/ Suggested-by: Jonathan Cameron <jonathan.cameron@huawei.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240308220055.2172956-8-dave.jiang@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-03-12cxl: Split out host bridge access coordinatesDave Jiang
The difference between access class 0 and access class 1 for 'struct access_coordinate', if any, is that class 0 is for the distance from the target to the closest initiator and that class 1 is for the distance from the target to the closest CPU. For CXL memory, the nearest initiator may not necessarily be a CPU node. The performance path from the CXL endpoint to the host bridge should remain the same. However, the numbers extracted and stored from HMAT is the difference for the two access classes. Split out the performance numbers for the host bridge (generic target) from the calculation of the entire path in order to allow calculation of both access classes for a CXL region. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240308220055.2172956-7-dave.jiang@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-03-12cxl: Split out combine_coordinates() for common shared usageDave Jiang
Refactor the common code of combining coordinates in order to reduce code. Create a new function cxl_cooordinates_combine() it combine two 'struct access_coordinate'. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240308220055.2172956-6-dave.jiang@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-02-16cxl: Fix sysfs export of qos_class for memdevDave Jiang
Current implementation exports only to /sys/bus/cxl/devices/.../memN/qos_class. With both ram and pmem exposed, the second registered sysfs attribute is rejected as duplicate. It's not possible to create qos_class under the dev_groups via the driver due to the ram and pmem sysfs sub-directories already created by the device sysfs groups. Move the ram and pmem qos_class to the device sysfs groups and add a call to sysfs_update() after the perf data are validated so the qos_class can be visible. The end results should be /sys/bus/cxl/devices/.../memN/ram/qos_class and /sys/bus/cxl/devices/.../memN/pmem/qos_class. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240206190431.1810289-4-dave.jiang@intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-02-16cxl: Remove unnecessary type cast in cxl_qos_class_verify()Dave Jiang
The passed in host bridge parameter for device_for_each_child() has unnecessary void * type cast. Remove the type cast. Suggested-by: Jonathan Cameron <Jonathan.Cameron@Huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240206190431.1810289-3-dave.jiang@intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-02-16cxl: Change 'struct cxl_memdev_state' *_perf_list to single 'struct ↵Dave Jiang
cxl_dpa_perf' In order to address the issue with being able to expose qos_class sysfs attributes under 'ram' and 'pmem' sub-directories, the attributes must be defined as static attributes rather than under driver->dev_groups. To avoid implementing locking for accessing the 'struct cxl_dpa_perf` lists, convert the list to a single 'struct cxl_dpa_perf' entry in preparation to move the attributes to statically defined. While theoretically a partition may have multiple qos_class via CDAT, this has not been encountered with testing on available hardware. The code is simplified for now to not support the complex case until a use case is needed to support that. Link: https://lore.kernel.org/linux-cxl/65b200ba228f_2d43c29468@dwillia2-mobl3.amr.corp.intel.com.notmuch/ Suggested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240206190431.1810289-2-dave.jiang@intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-01-05Merge branch 'for-6.7/cxl' into for-6.8/cxlDan Williams
Pick up a late locking change + fixup that is better as merge window material than rc material.
2024-01-05cxl: Fix device reference leak in cxl_port_perf_data_calculate()Dave Jiang
cxl_port_perf_data_calculate() calls find_cxl_root() and does not dereference the 'struct device' in the cxl_root->port. find_cxl_root() calls get_device() and takes a reference on the port 'struct device' member. Use the __free() macro to ensure the dereference happens. Fixes: 7a4f148dd8d5 ("cxl: Compute the entire CXL path latency and bandwidth data") Reviewed-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/170449246681.3779673.2288926019977963333.stgit@djiang5-mobl3 Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-01-05cxl: Convert find_cxl_root() to return a 'struct cxl_root *'Dave Jiang
Commit 790815902ec6 ("cxl: Add support for _DSM Function for retrieving QTG ID") introduced 'struct cxl_root', however all usages have been worked indirectly through cxl_port. Refactor code such as find_cxl_root() function to use 'struct cxl_root' directly. Suggested-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/170449246044.3779673.13035770941393418591.stgit@djiang5-mobl3 Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-12-22cxl: Check qos_class validity on memdev probeDave Jiang
Add a check to make sure the qos_class for the device will match one of the root decoders qos_class. If no match is found, then the qos_class for the device is set to invalid. Also add a check to ensure that the device's host bridge matches to one of the root decoder's downstream targets. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/170319626313.2212653.9021004640856081917.stgit@djiang5-mobl3 Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-12-22cxl: Store QTG IDs and related info to the CXL memory device contextDave Jiang
Once the QTG ID _DSM is executed successfully, the QTG ID is retrieved from the return package. Create a list of entries in the cxl_memdev context and store the QTG ID as qos_class token and the associated DPA range. This information can be exposed to user space via sysfs in order to help region setup for hot-plugged CXL memory devices. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/170319625109.2212653.11872111896220384056.stgit@djiang5-mobl3 Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-12-22cxl: Compute the entire CXL path latency and bandwidth dataDave Jiang
CXL Memory Device SW Guide [1] rev1.0 2.11.2 provides instruction on how to calculate latency and bandwidth for CXL memory device. Calculate minimum bandwidth and total latency for the path from the CXL device to the root port. The QTG id is retrieved by providing the performance data as input and calling the root port callback ->get_qos_class(). The retrieved id is stored with the cxl_port of the CXL device. For example for a device that is directly attached to a host bus: Total Latency = Device Latency (from CDAT) + Dev to Host Bus (HB) Link Latency + Generic Port Latency Min Bandwidth = Min bandwidth for link bandwidth between HB and CXL device, device CDAT bandwidth, and Generic Port Bandwidth For a device that has a switch in between host bus and CXL device: Total Latency = Device (CDAT) Latency + Dev to Switch Link Latency + Switch (CDAT) Latency + Switch to HB Link Latency + Generic Port Latency Min Bandwidth = Min bandwidth for link bandwidth between CXL device to CXL switch, CXL device CDAT bandwidth, CXL switch CDAT bandwidth, CXL switch to HB bandwidth, and Generic Port Bandwidth. [1]: https://cdrdv2-public.intel.com/643805/643805_CXL%20Memory%20Device%20SW%20Guide_Rev1p0.pdf Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/170319624458.2212653.13252496567443656371.stgit@djiang5-mobl3 Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-12-22cxl: Add callback to parse the SSLBIS subtable from CDATDave Jiang
Provide a callback to parse the Switched Scoped Latency and Bandwidth Information Structure (SSLBIS) in the CDAT structures. The SSLBIS contains the bandwidth and latency information that's tied to the CXL switch that the data table has been read from. The extracted values are stored to the cxl_dport correlated by the port_id depending on the SSLBIS entry. Coherent Device Attribute Table 1.03 2.1 Switched Scoped Latency and Bandwidth Information Structure (DSLBIS) Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/170319620635.2212653.5194389158785365150.stgit@djiang5-mobl3 Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-12-22cxl: Add callback to parse the DSLBIS subtable from CDATDave Jiang
Provide a callback to parse the Device Scoped Latency and Bandwidth Information Structure (DSLBIS) in the CDAT structures. The DSLBIS contains the bandwidth and latency information that's tied to a DSMAS handle. The driver will retrieve the read and write latency and bandwidth associated with the DSMAS which is tied to a DPA range. Coherent Device Attribute Table 1.03 2.1 Device Scoped Latency and Bandwidth Information Structure (DSLBIS) Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/170319620005.2212653.7475488478229720542.stgit@djiang5-mobl3 Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-12-22cxl: Add callback to parse the DSMAS subtables from CDATDave Jiang
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>