STRUCT ISST_PERF_FEATURE_CONTROL(9)

💅 struct isst_perf_feature_control(9) — like, the Kernel API Manual bestie ✨

okay so this is a page from the Kernel API Manual and honestly? she's small but she's mighty. we're talking about struct isst_perf_feature_control, no cap.

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🌸 NAME 🌸

struct isst_perf_feature_control — the literal structure you use to activate SST-BF/SST-TF. that's it, that's her whole job, and she does it flawlessly 💖

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✨ SYNOPSIS ✨

here's the whole vibe, copy it exactly pls, character for character:

struct isst_perf_feature_control {
    __u8 socket_id;
    __u8 power_domain_id;
    __u8 feature;
 };

three little __u8 fields and she's ready to go 🎀

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🫶 Members 🫶

let me introduce you to the squad, one field at a time:

• socket_id — the Socket/package id. which socket/package we're talking about, iykyk 🔥
• power_domain_id — the Power Domain id. yes bestie, this power domain specifically 💅
• feature — the flag bits, and listen carefully: bit 0 = SST-BF state, bit 1 = SST-TF state. two little bits doing the absolute most ⭐

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👑 Description 👑

so here's the tea: this structure is used to enable SST-BF/SST-TF using IOCTL ISST_IF_PERF_SET_FEATURE. that's the whole flex. you fill her in, you hand her to that ioctl, and she slays 🌈

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🦋 SEE ALSO 🦋

the whole extended friend group lives in the kernel file ./include/uapi/linux/isst_if.h, and honestly you should go say hi to all of them:

• struct isst_if_platform_info(9)
• struct isst_if_cpu_map(9)
• struct isst_if_cpu_maps(9)
• struct isst_if_io_reg(9)
• struct isst_if_io_regs(9)
• struct isst_if_mbox_cmd(9)
• struct isst_if_mbox_cmds(9)
• struct isst_if_msr_cmd(9)
• struct isst_if_msr_cmds(9)
• struct isst_core_power(9)
• struct isst_clos_param(9)
• struct isst_if_clos_assoc(9)
• struct isst_if_clos_assoc_cmds(9)
• struct isst_tpmi_instance_count(9)
• struct isst_perf_level_info(9)
• struct isst_perf_level_control(9)
• struct isst_perf_level_data_info(9)
• struct isst_perf_level_fabric_info(9)
• struct isst_perf_level_cpu_mask(9)
• struct isst_base_freq_info(9)
• struct isst_turbo_freq_info(9)

like, that's twenty-one structs, we're literally so blessed 😭💜

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ok quick sign-off bc I love you: this page comes from ./include/uapi/linux and it's dated October 2026, filed under struct isst_...ture_control(9). mwah, go enable some features bestie 💅🎀🌸