Hi All,
Hope you are doing well.
Platform Baytrail
Issue: Graphics External Display
VBIOS/VBT data
trying to see the MMIO or VBIOS data when a external display device is plugged/unplugged with DP/HDMI interface, which MMIO register is set or cleared
Any inputs are appreciated, some of the registers tried on Port B/Port C are given below. when Display is connected and when Display is not connected, both these instances
return the same data. Looking for register/bit that sets/clears when external display is connected/disconnected
printk(BIOS_DEBUG, "Intel Gfx BAR GTTMMADR\n");
printk(BIOS_DEBUG, " DP_B %X\n", read32(bar+0x180000+0x64100));
printk(BIOS_DEBUG, " DP_C %X\n", read32(bar+0x180000+0x64200));
printk(BIOS_DEBUG, " HDMIC %X\n", read32(bar+0x180000+0x61160));
printk(BIOS_DEBUG, " HDMIB %X\n", read32(bar+0x180000+0x61140));
printk(BIOS_DEBUG, " Hotplug control %X\n", read32(bar+0x180000+0x61164));
printk(BIOS_DEBUG, " pipeA control %X\n", read32(bar+0x180000+0x61204));
printk(BIOS_DEBUG, " pipeB control %X\n", read32(bar+0x180000+0x61304));
printk(BIOS_DEBUG, " porthot plug stat %X\n", read32(bar+0x180000+0x61114));
Display SPEC
Thanks
Rao