ra8_cache_store_demo Directory Reference

Directory dependency graph for ra8_cache_store_demo:

Directories
	inc
	src

Detailed Description

Runs the whole ra8_cache_store lifecycle end to end on the target – the persistent key-to-blob cache (#201) that backs compiled .rabook containers, which had no direct example until #257.

One pass covers: format and mount a store over LevelX standalone; put and get several keyed render/glyph blobs whose sizes cross sector boundaries and read each back byte-identical; pin the cover atlas so it can never be evicted, evict a render tile, and confirm the evicted key is now a miss, the survivors still resolve, and evicting the pinned atlas is refused as busy; re-put a new blob to prove the evicted entry's sectors were reclaimed; then checkpoint-close and re-mount over the same media with a fresh zeroed control block, confirming the survivors come back byte-identical, the evicted key stays gone, and the pin survived the checkpoint.

Why a RAM-backed NOR driver

The store's physical-flash bind is an injected callback (ra8_cache_store_nor_init_fn). Production binds the Octo-SPI driver; this demo binds a RAM driver, so the entire persistent-cache path runs in SRAM with no MMIO. That buys two things: it needs no external hardware, and because the path touches no peripheral register there is nothing for an emulator to model differently from the chip – an emulated run executes byte-identical instructions to the on-silicon one.

The RAM backing persists across close and re-init within one boot, which models the property the persistence check needs: control RAM lost, on-media content survives. A real Octo-SPI part persists across an actual power cycle; the RAM model persists across the in-process remount.

The app forces RA8_USE_LEVELX_STANDALONE=ON, which builds the vendored LevelX NOR sources with LX_STANDALONE_ENABLE so no ThreadX is pulled in.

The same core and the same RAM NOR driver are compiled into the host unit test, so just quality::local::test drives byte-identical logic on x86_64.