arch/mips/loongson2ef/lemote-2f/dma.c

File Facts

System

Linux kernel

Corpus path

arch/mips/loongson2ef/lemote-2f/dma.c

Extension

.c

Size

309 bytes

Lines

15

Domain

Architecture Layer

Bucket

arch/mips

Inferred role

Architecture Layer: implementation source

Status

source 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.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/dma-direct.h

Detected Declarations

• function phys_to_dma
• function dma_to_phys

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
#include <linux/dma-direct.h>

dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
{
	return paddr | 0x80000000;
}

phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dma_addr)
{
	if (dma_addr > 0x8fffffff)
		return dma_addr;
	return dma_addr & 0x0fffffff;
}

Annotation

• Immediate include surface: `linux/dma-direct.h`.
• Detected declarations: `function phys_to_dma`, `function dma_to_phys`.
• Atlas domain: Architecture Layer / arch/mips.
• Implementation status: source 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.