cpc_read_ffh(9)

💖 cpc_read_ffh(9) 💖

okay so this is from the Kernel API Manual (yes, the kernel one, we're being fancy today) and it's all about reading an FFH register. sit down bestie, this is gonna be a quick little slay 🫶

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✨ NAME ✨

cpc_read_ffh — Read FFH register 📖

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✨ SYNOPSIS ✨

int cpc_read_ffh (int cpunum , struct cpc_reg *reg , u64 *val );

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✨ ARGUMENTS ✨

• cpunum — the CPU number you wanna read from. like, which core's vibe are we checking 💅
• reg — the cppc register info. this is the little description of where the register lives
• val — place holder for the return value 🎀 the answer gets dropped in here so you can go get it later

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✨ DESCRIPTION ✨

Reads bit_width bits starting from a specified address and bit_offset. that's it. that's the whole thing. it goes to the address, it counts out bit_width bits from bit_offset, and it brings them back to you. lowkey iconic behavior honestly 🌸

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✨ RETURN ✨

0 for success 💖 and an error code if things go sideways 😭 (fr fr, always check it)

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✨ SEE ALSO ✨

the kernel file lives at ./drivers/acpi/cppc_acpi.c — go look if you want the full lore iykyk 👑

• acpi_get_psd_map(9)
• cpc_ffh_supported(9)
• cpc_supported_by_cpu(9)
• pcc_data_alloc(9)
• acpi_cppc_processor_probe(9)
• acpi_cppc_processor_exit(9)
• cpc_read_ffh_fb_ctrs(9)
• cpc_write_ffh(9)
• cppc_get_desired_perf(9)
• cppc_get_nominal_perf(9)
• cppc_get_highest_perf(9)
• cppc_get_epp_perf(9)
• cppc_get_perf_caps(9)
• cppc_perf_ctrs_in_pcc_cpu(9)
• cppc_perf_ctrs_in_pcc(9)
• cppc_get_perf_ctrs(9)
• cppc_set_epp(9)
• cppc_get_auto_act_window(9)
• cppc_set_auto_act_window(9)
• cppc_get_auto_sel(9)
• cppc_set_auto_sel(9)
• cppc_set_enable(9)
• cppc_get_perf(9)
• cppc_set_perf(9)
• cppc_get_perf_limited(9)
• cppc_set_perf_limited(9)
• cppc_get_transition_latency(9)

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🎀 that's the whole page bestie, go read your registers responsibly 💜

and that's a wrap!! this one came from the ./drivers/acpi corner of the world, dated October 2026 — so like, future vibes only 🌈✨ mwah 💅