drivers/cpufreq/powernv-cpufreq.c

File Facts

System

Linux kernel

Corpus path

drivers/cpufreq/powernv-cpufreq.c

Extension

.c

Size

31269 bytes

Lines

1161

Domain

Driver Families

Bucket

drivers/cpufreq

Inferred role

Driver Families: exported/initcall integration point

Status

integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

• Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
• Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Allocates kernel memory; connect allocation flags and lifetime to context constraints.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/kernel.h
• linux/sysfs.h
• linux/cpumask.h
• linux/module.h
• linux/cpufreq.h
• linux/smp.h
• linux/of.h
• linux/reboot.h
• linux/slab.h
• linux/string_choices.h
• linux/cpu.h
• linux/hashtable.h
• asm/cputhreads.h
• asm/firmware.h
• asm/reg.h
• asm/smp.h
• asm/opal.h
• linux/timer.h
• powernv-trace.h

Detected Declarations

• struct global_pstate_info
• struct pstate_idx_revmap_data
• struct powernv_smp_call_data
• enum throttle_reason_type
• function extract_pstate
• function idx_to_pstate
• function pstate_to_idx
• function hash_for_each_possible
• function reset_gpstates
• function init_powernv_pstates
• function pstate_id_to_freq
• function cpuinfo_nominal_freq_show
• function get_pmspr
• function set_pmspr
• function powernv_read_cpu_freq
• function powernv_cpufreq_get
• function set_pstate
• function get_nominal_index
• function powernv_cpufreq_throttle_check
• function calc_global_pstate
• function queue_gpstate_timer
• function gpstate_timer_handler
• function powernv_cpufreq_target_index
• function powernv_cpufreq_cpu_init
• function powernv_cpufreq_cpu_exit
• function powernv_cpufreq_reboot_notifier
• function powernv_cpufreq_work_fn
• function powernv_cpufreq_occ_msg
• function powernv_cpufreq_throttle_check
• function powernv_fast_switch
• function init_chip_info
• function for_each_possible_cpu
• function clean_chip_info
• function unregister_all_notifiers
• function powernv_cpufreq_init
• function powernv_cpufreq_exit
• module init powernv_cpufreq_init

Annotated Snippet

module_init(powernv_cpufreq_init);

static void __exit powernv_cpufreq_exit(void)
{
	cpufreq_unregister_driver(&powernv_cpufreq_driver);
	unregister_all_notifiers();
	clean_chip_info();
}
module_exit(powernv_cpufreq_exit);

MODULE_DESCRIPTION("cpufreq driver for IBM/OpenPOWER powernv systems");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Vaidyanathan Srinivasan <svaidy at linux.vnet.ibm.com>");

Annotation

• Immediate include surface: `linux/kernel.h`, `linux/sysfs.h`, `linux/cpumask.h`, `linux/module.h`, `linux/cpufreq.h`, `linux/smp.h`, `linux/of.h`, `linux/reboot.h`.
• Detected declarations: `struct global_pstate_info`, `struct pstate_idx_revmap_data`, `struct powernv_smp_call_data`, `enum throttle_reason_type`, `function extract_pstate`, `function idx_to_pstate`, `function pstate_to_idx`, `function hash_for_each_possible`, `function reset_gpstates`, `function init_powernv_pstates`.
• Atlas domain: Driver Families / drivers/cpufreq.
• Implementation status: integration implementation candidate.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.