drivers/dma/owl-dma.c

File Facts

System

Linux kernel

Corpus path

drivers/dma/owl-dma.c

Extension

.c

Size

32425 bytes

Lines

1278

Domain

Driver Families

Bucket

drivers/dma

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.
• Touches IRQ or DMA behavior; this matters for the representative real-device path.
• 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/bitops.h
• linux/clk.h
• linux/delay.h
• linux/dmaengine.h
• linux/dma-mapping.h
• linux/dmapool.h
• linux/err.h
• linux/init.h
• linux/interrupt.h
• linux/io.h
• linux/mm.h
• linux/module.h
• linux/of.h
• linux/of_dma.h
• linux/platform_device.h
• linux/slab.h
• virt-dma.h

Detected Declarations

• struct owl_dma_lli
• struct owl_dma_txd
• struct owl_dma_pchan
• struct owl_dma_vchan
• struct owl_dma
• enum owl_dmadesc_offsets
• enum owl_dma_id
• function pchan_update
• function pchan_writel
• function pchan_readl
• function dma_update
• function dma_writel
• function dma_readl
• function llc_hw_ctrla
• function llc_hw_ctrlb
• function llc_hw_flen
• function owl_dma_free_lli
• function owl_dma_cfg_lli
• function owl_dma_pchan_busy
• function owl_dma_terminate_pchan
• function owl_dma_pause_pchan
• function owl_dma_resume_pchan
• function owl_dma_start_next_txd
• function owl_dma_phy_free
• function owl_dma_interrupt
• function for_each_set_bit
• function owl_dma_free_txd
• function owl_dma_desc_free
• function owl_dma_terminate_all
• function owl_dma_config
• function owl_dma_pause
• function owl_dma_resume
• function owl_dma_getbytes_chan
• function list_for_each_entry
• function owl_dma_tx_status
• function owl_dma_phy_alloc_and_start
• function owl_dma_issue_pending
• function for_each_sg
• function owl_dma_free_chan_resources
• function owl_dma_free
• function list_for_each_entry_safe
• function owl_dma_probe
• function owl_dma_remove
• function owl_dma_init
• function owl_dma_exit
• module init owl_dma_init

Annotated Snippet

subsys_initcall(owl_dma_init);

static void __exit owl_dma_exit(void)
{
	platform_driver_unregister(&owl_dma_driver);
}
module_exit(owl_dma_exit);

MODULE_AUTHOR("David Liu <liuwei@actions-semi.com>");
MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
MODULE_DESCRIPTION("Actions Semi Owl SoCs DMA driver");
MODULE_LICENSE("GPL");

Annotation

• Immediate include surface: `linux/bitops.h`, `linux/clk.h`, `linux/delay.h`, `linux/dmaengine.h`, `linux/dma-mapping.h`, `linux/dmapool.h`, `linux/err.h`, `linux/init.h`.
• Detected declarations: `struct owl_dma_lli`, `struct owl_dma_txd`, `struct owl_dma_pchan`, `struct owl_dma_vchan`, `struct owl_dma`, `enum owl_dmadesc_offsets`, `enum owl_dma_id`, `function pchan_update`, `function pchan_writel`, `function pchan_readl`.
• Atlas domain: Driver Families / drivers/dma.
• Implementation status: integration implementation candidate.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
• IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.

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.