c97006046c
The per-device CDAT data provides performance data that is relevant for mapping which CXL devices can participate in which CXL ranges by QTG (QoS Throttling Group) (per ECN: CXL 2.0 CEDT CFMWS & QTG_DSM) [1]. The QTG association specified in the ECN is advisory. Until the cxl_acpi driver grows support for invoking the QTG _DSM method the CDAT data is only of interest to userspace that may need it for debug purposes. Search the DOE mailboxes available, query CDAT data, cache the data and make it available via a sysfs binary attribute per endpoint at: /sys/bus/cxl/devices/endpointX/CDAT ...similar to other ACPI-structured table data in /sys/firmware/ACPI/tables. The CDAT is relative to 'struct cxl_port' objects since switches in addition to endpoints can host a CDAT instance. Switch CDAT support is not implemented. This does not support table updates at runtime. It will always provide whatever was there when first cached. It is also the case that table updates are not expected outside of explicit DPA address map affecting commands like Set Partition with the immediate flag set. Given that the driver does not support Set Partition with the immediate flag set there is no current need for update support. Link: https://www.computeexpresslink.org/spec-landing [1] Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Co-developed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Ira Weiny <ira.weiny@intel.com> [djbw: drop in-kernel parsing infra for now, and other minor fixups] Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/20220719205249.566684-7-ira.weiny@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> |
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| .. | ||
| core | ||
| acpi.c | ||
| cxl.h | ||
| cxlmem.h | ||
| cxlpci.h | ||
| Kconfig | ||
| Makefile | ||
| mem.c | ||
| pci.c | ||
| pmem.c | ||
| port.c | ||