ipu6epmtl_fw.bin: C-PHY support needed for Meteor Lake (Surface Pro 10 / IMX681)

[djmulder]

Summary

The current ipu6epmtl_fw.bin does not support C-PHY stream sources,
making it impossible to use C-PHY sensors on Meteor Lake under Linux.

Hardware

• Device: Microsoft Surface Pro 10 for Business
• IPU: Intel IPU6EP-MTL (PCI 8086:7d19, Meteor Lake)
• Front camera: Sony IMX681 (ACPI: SONY0681)
• Interface: MIPI CSI-2 C-PHY, 2 trios, 380.8 MHz symbol rate
• CSI port: 4 (PHY_E, CSI2_3PH_PORTA)

Findings

1. Linux firmware (ipu6epmtl_fw.bin, main branch) rejects stream source
   CSI2_3PH_CPHY_PORT0 (src=6) with FW_INTERNAL_CONSISTENCY error
   (error=1, details=18).

2. The Windows driver (iacamera64.sys) successfully uses src=6 for this
   sensor, confirmed via ETW trace analysis.

3. The Windows firmware binary (from the iacamera64 driver package, same
   size 466944 bytes) is a different build that supports C-PHY. The Linux
   firmware does not.

4. All kernel driver infrastructure is complete:

   • C-PHY flag detection and propagation
   • CSI frontend registers correct (FE_MODE=1, PPI_PHY_TYPE=1)
   • DWC PHY powers up to IDLE state
   • IMX681 sensor starts streaming
   • Firmware accepts src=4 stream open, but never sends FRAME_SOF

Request

Please release an updated ipu6epmtl_fw.bin with C-PHY support,
either by supporting CSI2_3PH_CPHY_PORT0 (src=6) or adding C-PHY
processing for CSI2_3PH_PORTA (src=4).

References

• Kernel patches: patches: Add kernel 7.0 support with Surface Pro 10 camera patches linux-surface/linux-surface#2156
• linux-surface PR: patches: Add kernel 7.0 support with Surface Pro 10 camera patches linux-surface/linux-surface#2156