Module chain 

The raw linked-list layer: DMA channel 2 walking a chain of GP0 nodes.

Each node is a tag word, the next node’s address in bits 23..=0 (LIST_END ends the list) and the payload word count in bits 31..=24, followed by that many GP0 words. The DMA controller follows the links on its own, so whatever a tag names is read with no regard for Rust’s borrows: that is why submit_raw and submit_async_raw are unsafe. The safe layers above them prove their contract instead: crate::frame with lifetimes, StaticChain with 'static immutability, and crate::ordered with 'static storage it owns.

Every wait here is bounded. A walk that outlives its budget is aborted and the GPU’s half-read command discarded, so a wedged channel costs a reset instead of a hang; crate::recovery_stats counts the aborts.

Structs

DrawDoneNode

A linked-list DMA node holding only GP0(1Fh), for the end of a chain.

StaticPacket

One immutable linked-list node: W GP0 words, then the end of the list.

Constants

LIST_END

The link value that ends a list.

MAX_NODE_WORDS

Most payload words one linked-list DMA node may carry (the words after its tag), the depth of the GPU’s command FIFO.

Statics

DRAW_DONE_NODE

The shared GP0(1Fh) node: one payload word, then the end of the list.

Traits

StaticChain

A complete, immutable linked list: StaticPacket or DrawDoneNode.

Functions

submit_async_raw^⚠

Kick the chain at head and return while the GPU walks it.

submit_raw^⚠

Kick the chain at head and wait until it has been walked.

wait

Wait until the walk kicked last has finished reading its chain.