iMX6Q : Yocto and HDMI support

[milo]

I have a Freescale sabre, for which I have generate core-image-x11 with yocto. Booting and using it with serial port is ok, but I can't use the HDMI display. The HDMI is detected by u-boot (I an see two tux on the hdmi display), but not after. Here are some informations given by u-boot :

U-Boot 2014.10+fslc+g5fd0b60 (Feb 27 2015 - 11:26:20) CPU: Freescale i.MX6Q rev1.2 at 792 MHz Reset cause: POR Board: MX6-SabreSD I2C: ready DRAM: 1 GiB MMC: FSL_SDHC: 0, FSL_SDHC: 1, FSL_SDHC: 2 auto-detected panel HDMI Display: HDMI (1024x768) In: serial Out: serial Err: serial PMIC: PFUZE100 ID=0x10 Net: FEC [PRIME] 

I have tried this in u-boot :

setenv mmcargs 'setenv bootargs console=ttymxc0,115200 root=/dev/mmcblk0p2 rootwait rw video=mxcfb0' 

But it doesn't change anything, even if the modification can be seen in /proc/cmdline after the booting ; and

setenv mmcargs 'setenv bootargs console=ttymxc0,115200 root=/dev/mmcblk0p2 rootwait rw video=mxcfb0:dev=hdmi' 

makes the booting stopping at starting kernel.
Does anyone know how to support hdmi ?

[saurabh206]

Hi

Can you try

video=mxcfb0:dev=hdmi, 1920x1080M@60, if=RGB24

For more information you can refer i.MX6_SABRE_AI_Linux_Release_note.pdf.

[milo]

Well... It was working for core-image-base, but it doesn't work with core-image-x11. It works if we don't add `video=mxcfb0:dev=hdmi, 1920x1080M@60, if=RGB24`. Any idea why ?

Btw, I haven't found i.MX6_SABRE_AI_Linux_Release_note.pdf. Where can I find it ?

[saurabh206]

Hi

https://www.freescale.com/webapp/Download?colCode=L3.10.17_1.0.0_LINUX_DOCS&appType=license&location...

Download L3.10.17_1.0.0_LINUX_DOCS.

[milo]

I use a HDMI to DVI cable, so maybe there is a problem with it. But it was working on core-image-sato.

(Yes, this is an up)

[saurabh206]

Its good that HDMI is working at your end.

[milo]

But it isn't working right now, with core-image-x11. And I don't understand why, given that I have try all what I've found. So if you had any clue, I'd be grateful.

[eugenevolkov]

Hi, i have same problem, in core-image-qt5. i see on HDMI monitor logo, but after start Xserver, i see black screen and blinking cursor.

[milo]

Thanks, it was really instructive. Is it only me, or are these documents difficult to find ?

For my problem, I have tried all the kernel boot parameters given for HDMI.

`video=mxcfb0:dev=hdmi,1920x1080M@60,if=RGB24` and `video=mxcfb0:dev=hdmi,1920x1080M@60,if=RGB24 ldb=sep1` make the boot stopping at `starting kernel`. With `video=mxcfb0:dev=ldb,LDBXGA,if=RGB666 video=mxcfb1:dev=hdmi,1920x1080M@60,if=RGB24` it boots, but the HDMI isn't working. Any suggestion ?

Again, thanks a lot for your patience.

[milo]

Great, thanks.