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CXL Reset is device scoped, requires affected memory to be idle, invalidates CPU caches, restores cached HDM decoder state, and does not request Memory Clear. Signed-off-by: Srirangan Madhavan --- Documentation/ABI/testing/sysfs-bus-pci | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index b767db2c52cb..5ab46a4340ae 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -153,6 +153,20 @@ Description: "default" enables all supported reset methods in the default ordering. + If present, "cxl_reset" selects CXL Reset for CXL Type 2 + devices that advertise CXL Reset support and whose reset scope is + limited to the selected PCI function. The method is not listed + when CXL Reset would affect another CXL.cache or CXL.mem function. + + Before issuing CXL Reset, the kernel quiesces the PCI function, + rejects the operation if cached HDM state is unavailable or + affected CXL memory is busy, invalidates CPU caches for enabled + HDM ranges, disables CXL.cache, and initiates cache write-back + where supported. After reset, the kernel restores PCI config + state needed to access HDM MMIO, restores cached HDM decoder + state, and completes PCI reset recovery. "cxl_reset" does not + request CXL Reset Memory Clear. + What: /sys/bus/pci/devices/.../reset Date: July 2009 Contact: Michael S. Tsirkin -- 2.43.0