c0410449cb
Also: redox-drm DPCD AUX stub replaced with real implementation. - redox-drm/intel/display.rs: read_dpcd skeleton (hardcoded vec![0x12,0x0A,0x84,0x01]) replaced with real native AUX channel read. aux_read() implements the DP AUX protocol: native read cmd (0x9) + 20-bit address + len-1 written to DP_AUX_CH_DATA, SEND_BUSY + message size + MTL POWER_REQUEST to DP_AUX_CH_CTL, DONE/error polling, ACK reply check, payload extract. Per zero-stub policy. Reference: Linux intel_dp_aux.c + intel_dp_aux_regs.h, VESA DP 1.4. - redox-drm/intel/backlight.rs: remove leftover fake_mmio_size test artifact. - Plan doc: Phase 3.3 marked code-complete (GMBUS EDID real, DPCD AUX real; modeset proof needs host). ACPICA assessment updated with GPE _Lxx/_Exx dispatch and PM timer.