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[Why] DCN 3.6+ hardware supports CRC-32 polynomial in addition to the legacy CRC-16. Enable 32-bit CRC values per color component for improvement of precision in display validation. [How] When userspace sets crc_poly_mode (0=CRC-16, 1=CRC-32) via the debugfs interface, the value is stored in dm_irq_params.crc_poly_mode. When CRC source configuration triggers amdgpu_dm_crtc_configure_crc_source(), crc_poly_mode is retrieved from dm_irq_params and passed to dc_stream_configure_crc(). In the DC layer, dc_stream_configure_crc() sets crc_poly_mode into the crc_params structure and passes it to optc35_configure_crc(). If the hardware supports the OTG_CRC_POLY_SEL register, the register is programmed to select CRC-16 or CRC-32 polynomial. When reading CRC values, optc35_get_crc() checks whether CRC32 register masks are available. If present, it reads 32-bit CRC values from OTG_CRC0/1_DATA_R32/G32/B32 registers; otherwise, it falls back to reading 16-bit CRC values from legacy OTG_CRC0/1_DATA_RG/B registers. Reviewed-by: ChiaHsuan Chung <chiahsuan.chung@amd.com> Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com> Signed-off-by: Wayne Lin <wayne.lin@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>