[coreboot-gerrit] Change in coreboot[master]: soc/intel/apl: Add panel power and backlight configuration

[Wolfgang Kamp (Code Review)]

Wolfgang Kamp has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/40694 )

Change subject: soc/intel/apl: Add panel power and backlight configuration
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Patch Set 4:

I have tested the patch with real hardware on Apollo Lake SMARC modul with baseboard and LVDS TFT display. I used the following devicetree entries:
# IGD Displays
    register "gpu_pp[0].up_delay_ms"		= "100"
    register "gpu_pp[0].down_delay_ms"		= "500"
    register "gpu_pp[0].cycle_delay_ms"		= "500"
    register "gpu_pp[0].backlight_on_delay_ms"	= "  1"
    register "gpu_pp[0].backlight_off_delay_ms"	= "200"
    register "gpu_blc[0].pwm_hz"	  		= "192"
    register "gpu_blc[0].polarity"	  		= "GPU_BACKLIGHT_POLARITY_HIGH"

Software configuration: coreboot using libgfxinit and UEFI payload.
It works fine! No problems encountered.