arch/parisc/lib/delay.c

File Facts

System

Linux kernel

Corpus path

arch/parisc/lib/delay.c

Extension

.c

Size

1830 bytes

Lines

73

Domain

Architecture Layer

Bucket

arch/parisc

Inferred role

Architecture Layer: exported/initcall integration point

Status

integration implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

• CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
• Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.

Dependency Surface

• linux/module.h
• linux/preempt.h
• linux/init.h
• asm/delay.h
• asm/special_insns.h
• asm/processor.h

Detected Declarations

• function Copyright
• function __udelay
• export __udelay

Annotated Snippet

if (unlikely(cpu != smp_processor_id())) {
			loops -= (now - bclock);
			cpu = smp_processor_id();
			bclock = mfctl(16);
		}
	}
	preempt_enable();
}


void __udelay(unsigned long usecs)
{
	__cr16_delay(usecs * ((unsigned long)boot_cpu_data.cpu_hz / 1000000UL));
}
EXPORT_SYMBOL(__udelay);

Annotation

• Immediate include surface: `linux/module.h`, `linux/preempt.h`, `linux/init.h`, `asm/delay.h`, `asm/special_insns.h`, `asm/processor.h`.
• Detected declarations: `function Copyright`, `function __udelay`, `export __udelay`.
• Atlas domain: Architecture Layer / arch/parisc.
• Implementation status: integration implementation candidate.

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.