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This register is sticky and remains set until reset or >> OS clears it by writing 0. >> >> The interface is exposed as: >> /sys/devices/system/cpu/cpuX/cpufreq/perf_limited > What is the intended use of this interface? The performance limited > register has a specific format of status bits with feedback about > performance being limited temporarily and the user can only clear it. > > "Contains a resource descriptor with a single Register() descriptor > that describes the register to read to determine if performance was > limited. A nonzero value indicates performance was limited. This > register is sticky, and will remain set until reset or OSPM clears > it by writing 0. See the section “Performance Limiting” for more > details." Also, "The performance limited register should only be used > to report short term, unpredictable events (e.g., PROCHOT being > asserted)." > > Therefore, I'm not seeing the value of exposing this via sysfs. > > Thanks, > Ionela. > This enables users to detect if platform throttling impacted a workload. Users clear the register before execution, run the workload, then check afterward if set, hardware throttling (thermal/power/current limits) occurred during that time window. The write operation can be restricted to only accept 0 (clearing) to prevent writing arbitrary values. Thank you, Sumit Gupta ....