Robert Allan JamesandClaude Sonnet 5
dc9445abec
FABRIC-3.md §IV.3 item 7's code audit found GICD_BASE_PA/GICC_BASE_PA hardcoded to QEMU virt-machine constants (0x08000000/0x08010000), self-documented as a deliberate exception because QEMU's aarch64 UEFI firmware never forwards a DTB. That premise doesn't hold on the native Pi 5 boot path (rpi5_native_boot.c), which does have a real DTB and calls this same, unmodified apic_init() -- which ignored boot_info entirely and always programmed the QEMU addresses. Real BCM2712 GIC-400 is at 0x10_7fff9000 (confirmed against bcm2712.dtsi's axi/gicv2 nodes), a completely different region of the address space. Fixed per direct instruction, naming this finding specifically. apic_init() now calls gic_bases_from_dtb() first: fdt_valid(dtb) -> fdt_find_node_by_compatible(dtb, "arm,gic-400") -> fdt_find_prop_in_node(..., "reg", ...), reading the first two 2-address-cell/2-size-cell entries (GICD, then GICC -- the standard arm,gic-400 binding order). Falls back to the QEMU constants on any failure (no DTB, no matching node), so the existing QEMU/UEFI path is unchanged. GICD_BASE_PA/GICC_BASE_PA became s_gicd_base/s_gicc_base (module-static uintptr_t, no longer compile-time constants on this path) -- every MMIO call site (apic_init, apic_spi_enable, apic_read_iar, apic_eoi_intid) now reads through them. Three-arch QEMU acceptance run exercised the guard itself, not just compiled it: the aarch64 boot log shows "GICv2: no DTB GIC node -- using QEMU virt-machine defaults" followed by the unchanged "distributor+CPU interface enabled, PPI 30" line, then boots clean to zuse)ok>. The success branch (a real DTB with a matching node) stays unverified until real Pi 5 hardware -- this build never has a devicetree to exercise it against. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_019YcT3H2PQeyujrzjqS3Var
capsules/
FORTH personality files loaded by the VM at boot. A capsule is an immutable, content-addressed payload; its XXHash64 hash is its identity. Any mutation changes the hash and the birth protocol rejects the image.
Key files
| File | Type | Purpose |
|---|---|---|
init.4th |
(m) MAMA_INIT |
Default Mama VM personality — loaded at LBN 2048 |
ACL.4th |
user | Word-level ACL system; self-activating at boot |
zuse.4th |
user | Bootstrap superuser; loaded by ACL.4th |
doe.4th |
user | DoE workload words (EXEC-DOE) — opt-in |
init-0.4th … init-9.4th |
(p) |
Numbered personality variants |
init-l8-*.4th |
(p) |
L8 Jacquard mode variants (stable/volatile/diverse/temporal/transition/omni) |
hermes/init.4th |
(p) |
Hermes baby VM personality |
artemis/init.4th |
(p) |
Artemis baby VM personality |
Block namespace
Block ranges are shared across all loaded capsules — collisions cause silent word-definition overwrites.
| Range | Owner |
|---|---|
| 2048–2099 | init.4th |
| 2100–2199 | doe.4th |
| 3000–3999 | workload capsules |
| 4000+ | user-defined (ACL.4th, zuse.4th, …) |
Each block is limited to 1024 bytes. Verify with wc -c before committing.
See also
experiments/bare_metal/README.md— DoE protocols and block namespace rulesdocs/03-architecture/word-acl/DESIGN.md— ACL system designtools/mkcapsule.c— assembles capsules intocapsule_generated.c- Project root