intel: HDMI infoframes + VBT parser (Phase 1 + Phase 3)
Add hdmi.rs — AVI infoframe programming for HDMI monitors.
- program_avi(): computes VIC (Video Identification Code) from
standard mode table (640x480 through 3840x2160), aspect ratio,
scan info, colorimetry, quantization. Programs HSW_TVIDEO_DIP_CTL
(0x61180) and AVI_DATA (0x61184) registers per-pipe
- disable(): clear VIDEO_DIP_ENABLE bit
- checksum(): 256-byte wrap check for infoframe validation
Add vbt.rs — Video BIOS Table parser.
- parse(): validate signature, extract version and BDB offset
- parse_bdb(): walk BDB blocks, parse child device config (block 33)
extracting DVO port, DDC pin, HDMI/DP/eDP support flags
- port_type_for_index(): map port index to PortType using VBT data
- ChildDeviceConfig with aux_channel detection
Linux reference: intel_hdmi.c, intel_bios.c (VBT parsing)
vasilito
89eee72a0f