Display pixclk on imx53

[christophe]

Hi,

with a imx53qsb board, DISP0_DCLK,signal present on expansion header at pin 43 doesn't contain pixclk clock signal from display. Other signals like DISP0_VSYNC, DISP0_HSYNC or DISP0_DRDY are however ok.

I plan to connect parallel display port di0 to a lcd and i need DISP_DCLK signal.

Is there any bootargs command or other to activate it ?

Thanks,

Christophe.

[weidong_sun]

Hi,Christophe,

     Connect HDMI daughter board and connect HDMI cable to monitor with HDMI, The

Try the following setting for u-boot environment:

u-boot > setenv console=ttymxc0 init=/init androidboot.console=ttymxc0 video=mxcdi0fb:RGB24,1280x720M@60,bpp=32 hdmi di0_primarypmem=64M,64M fbmem=16M gpu_memory=64M

u-boot > save

Regards,

Weidong

[weidong_sun]

Hi,Christophe,

      Did the above u-boot environment help you resolve your issue ? if it is OK, please press correct answer button !

Regards,

Weidong

[christophe]

Hi Weidong,

It's not really a hdmi problem. But it seems that suppressing ldb extension is enough like below:

set bootargs console=ttymxc0,115200 video=mxcdi0fb:RGB24,720P60 di0_primary.

Netherveless, i take note of your response for further applications.

Rgds,

Christophe

[weidong_sun]

Hello,Christophe

     DISP0_DCLK signal is pixclk of DISP0, you should see it on J11. Did you find it ?

weidong

[christophe]

Hi Weidong,

I can see pixclk now. Things are clear on that.

Now, i've tried your bootargs line and imx crashes when booting. Here's the last lines just before the crash:

vmap allocation for size 469766144 failed: use vmalloc=<size> to increase size.

fbcvt: 1280x720@60: CVT Name - .921M9

mxc_ipu mxc_ipu: Channel already disabled 9

mxc_ipu mxc_ipu: Channel already uninitialized 9

IPU DMFC DP HIGH RESOLUTION: 1(0,1), 5B(2~5), 5F(6,7)

The fact is i usually don't reserve memory at boot stage. Is it better ? Can you explain please.

Christophe

[weidong_sun · Accepted solution]

Hello,Christophe,

      The following setting is also OK:

u-boot >setenv bootargs console=ttymxc0 init=/init androidboot.console=ttymxc0 video=mxcdi0fb:RGB24,1280x720M@60 di0_primary hdmi

       system will assign memory automatically.

Weidong

[christophe]

Hi Weidong,

Indeed, it works.

Thanks.

Christophe