pagecache Directory Reference

Directory dependency graph for pagecache:

Directories
	src

Detailed Description

On-silicon exercise of the reflow import-time pagination cache (#117, the #79 cache) against a real microSD volume through ra8_fs – the exact storage path the e-reader uses – so the serialise / persist / load / invalidate logic meets real SD timing and the FAT read and write paths rather than only a host unit test.

From a fixed chapter laid out with an SD-loaded font it checks three things:

1. Round-trip. Lay out live, serialise to a blob, write it to the card, read it back, load it into a fresh engine and re-serialise – the reloaded blob must be byte-for-byte equal to the live one. Since the serialised form is the per-page glyph and page data, equal blobs mean the layout was restored exactly.
2. Invalidation. Load that same blob into an engine initialised at a different font size and require k_ra8_err_invalid_state. The key mismatch has to be caught, or a stale page gets served.
3. Reset survival. A second boot against a persisted card must report a hit and serve from the on-disk cache without a fresh layout.

The gate is a memprobe rather than the console, for the same reason as the sibling SD apps: an SD app drives the SCI0 Simple-SPI bus, and an emulator that folds every SCI channel onto one line interleaves the SCI8 banner with SPI traffic. g_pc_heartbeat advances only after every assertion passes; any failure stamps g_pc_err with the first failing stage and parks in wfi without bumping it.

Needs a PMOD MicroSD in Pmod2 (J25) with a card inserted, and may format the card. The font and cache file self-provision, so a blank FAT card works, and an unseated card is the first thing to rule out when this fails. Rendering the cached pages to pixels is sd_font_render / ereader_ui; this is the serialise/load layer only.