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KERNEL · 0.6.0

Apple Silicon HAL Batch 11: UltraFusion, USB-C Mux, Secboot Chain, ProRes + PPC Grackle, Heathrow, MACE, CUDA PMU

June 22, 2026 · sigil-kernel · Sigil-Docs
kernel hal apple-silicon powerpc hardware 0.6.0

sigil-kernel's eleventh HAL batch adds 8 more seams — four Apple Silicon and four PowerPC. Apple side: UltraFusion die-to-die interconnect (M1 Ultra, 2 dies, 32GB per die, cross-die transactions, E+P cluster affinity), USB-C mux alt-mode arbiter (4 ports, USB3/DP-Alt/TB4/USB4 priority select, partner capability → best mode), secure boot chain of trust (5-stage BootROM→LLB→iBoot→Kernel→User, PCR-style measurement extension, boot policy SIP/SSV/kext/debug), ProRes media engine (2-engine enc+dec, 4-deep frame queue, proxy/LT/normal/HQ quality tiers, byte estimator). PowerPC side: Grackle MPC106 PCI host bridge (4 slots, ATI Rage128 + Apple-USB + SMC-Ethernet, 66MHz bus), Heathrow Mac I/O (64-IRQ controller, 12-line GPIO, feature-ctrl), MACE Am79C940 Ethernet (MACCC promisc/TX/RX/loopback, 64-bit multicast, loopback TX→RX), CUDA PMU (battery/AC/lid, RTC Mac epoch, scheduled wake, thermal shutdown 80°C). All QEMU PASS. (sigil-kernel 2acd370, 7a7ca6c, 7853e76, 4535635)

Apple Silicon HAL QEMU batch verification
Apple Silicon HAL QEMU batch verification

apple_nvlink.sg — M1 Ultra UltraFusion Die-to-Die Interconnect (2acd370)

apple_nvlink.sg models the UltraFusion die-to-die interconnect used in the M1 Ultra — Apple's solution for doubling M1 Max dies into a single logical package. The seam tracks 2 dies, each with 32 GB of DRAM, along with per-die active status, credit availability, and accumulated bandwidth.


apple_usbc_mux.sg — 4-Port USB-C Alt-Mode Multiplexer (7a7ca6c)

apple_usbc_mux.sg models the USB-C alt-mode mux arbiter that decides which protocol a given USB-C port carries at any moment — USB3, DisplayPort Alt, Thunderbolt 4, or USB4.


apple_secboot_chain.sg — 5-Stage Chain of Trust (7853e76)

apple_secboot_chain.sg models the OS-level chain-of-trust policy that Apple's Secure Enclave and SecureBoot.efi enforce at runtime — PCR-style measurements, SIP/SSV state, and kext policy.

Relationship to apple_secboot: apple_secboot (the HARD STOP fix, 6dfc207) models the iBoot-level FNV hash chain for the boot stages themselves. apple_secboot_chain models the OS-level chain-of-trust policy that SecureBoot.efi / Apple's Secure Enclave enforces at runtime — PCR measurements, SIP/SSV state, kext policy. Together they cover the full secure boot surface from hardware fuses to runtime kernel trust.


apple_prores.sg — M1 Pro/Max/M2 ProRes Hardware Media Engine (4535635)

apple_prores.sg models Apple's dedicated ProRes hardware acceleration engine present in M1 Pro, M1 Max, and M2. ProRes encoding and decoding bypass the GPU entirely, running on a fixed-function media engine.


ppc_grackle.sg — G3 Grackle MPC106 PCI Host Bridge (2acd370)

ppc_grackle.sg models the Motorola MPC106 "Grackle" PCI host bridge used in the Power Macintosh G3 (Beige). The Grackle sits at the top of the PCI bus and exposes four downstream device slots.

Slot 0x00
MPC106 itself (self-identification). Vendor 0x1057, class 0x06 (bridge).
Slot 0x01
ATI Rage128 GPU — the primary display adapter in Beige G3 systems.
Slot 0x02
Apple USB controller — providing the G3's original USB 1.1 ports.
Slot 0x03
SMC Ethernet — the integrated 10/100 Ethernet adapter.

Per-device state tracks vendor/device ID, class, and BAR0. A present-count field tracks how many slots are populated. 66 MHz PCI bus. Base address 0x469000. PASS: GK init=1 pop=1 cls=1


ppc_heathrow.sg — G3 Heathrow Mac I/O Hub (7a7ca6c)

ppc_heathrow.sg models the Apple Heathrow Mac I/O ASIC, the peripheral hub that connects the G3's CPU to its I/O devices via a single chip — much as Apple's later southbridge designs would do for the G4.


ppc_mace.sg — G3 MACE Am79C940 Ethernet (7853e76)

ppc_mace.sg models the AMD Am79C940 MACE (Media Access Controller for Ethernet) used in the original Macintosh G3. This is a classic 10BASE-T/AUI integrated Ethernet controller.


ppc_pmu.sg — G3/G4 CUDA PMU Power Management Unit (4535635)

ppc_pmu.sg models the CUDA PMU (Power Management Unit) embedded in G3 and G4 Power Macintosh systems. CUDA handles battery/AC state, RTC, scheduled wake, keyboard backlight, and thermal shutdown — the full system power surface below the OS.


HAL seam summary — batch 11

Seam fileCommitPlatformAddressPASS
apple_nvlink.sg2acd370Apple Silicon (M1 Ultra)0x468000NVL init=1 up=1 xact=1
ppc_grackle.sg2acd370PowerPC G30x469000GK init=1 pop=1 cls=1
apple_usbc_mux.sg7a7ca6cApple Silicon0x46A000UCMX init=1 dp=1 tb=1
ppc_heathrow.sg7a7ca6cPowerPC G30x46B000HW init=1 irq=1 gpio=1
apple_secboot_chain.sg7853e76Apple Silicon0x46C000SBC init=1 cot=1 flt=1
ppc_mace.sg7853e76PowerPC G30x46D000MACE init=1 lb=1 mac=1
apple_prores.sg4535635Apple Silicon (M1 Pro/Max/M2)0x46E000PR init=1 enc=1 byt=1
ppc_pmu.sg4535635PowerPC G3/G40x46F000PMU init=1 slp=1 thm=1