DM8148 HD_VENC VOUT1 function

Hi,

Following needs to be done

1. You have to setup the pin mux for DVO1. This you can find from pin muxing utility.

2. You dont have to load ti81xxhdmi.ko module.

3. you need to set timings using same sysfs entries as you were using earlier.

Additionally you have to make sure your exteranal DAC is also configured properly.

Regards,

Hardik Shah

Hi HardiShah

I'm working with the dm8168 and trying to do something similar to what was mentioned above.

1. I believe I set my DVO1 pin mux values correct.  I did this inside devices.c under ti81xx_video_mux. 

2. inside the kernel i disabled the hdmi driver.  I believe it's gone since i do a find -name ti81xxhdmi and it's gone.

3. so the timing signals I'm assuming stay the same in the vpss directory since vout1 is the same as hdmi.

Lastly i'm not too sure what these dac values are supposed to be set to.  I think that is the only step missing but maybe something above is incorrect.

Please give me some suggestions i may be able to try to solve this problem.

Thanks,

Rodrigo

Hi,

Which PSP release are you using. Can you please dump output

cat /sys/devices/platform/vpss/display0/output

I think you have configured Venc for embedded sync and your external decoder/LCD is for discrete sync.   Dumping above output will clear out  things.

Regards,

Hardik Shah

Hi,

I have dumped the file and this is what i got.

/ # cat sys/devices/platform/vpss/display0/output
triplediscrete,rgb888,0/0/0/0

Our fpga is expecting ycbcr 4:2:2.  

Rodrigo

Sorry just realized I didn't answer the first part of your question.  We are using psp 04.00.01.13

Rodrigo

Rodrigo,

1. please make sure that pin mux setting do take effect.  M3 firmware may overwrite the DVO1 pinmux.

2. you can change the VENC output to yuv422

echo 0 > /sys/devices/platform/vpss/display0/enabled

echo double/doublediscreted,yuv422spuv > /sys/devices/platform/vpss/display0/enabled

echo 1 > /sys/devices/platform/vpss/display0/enabled

Regards

yihe

Thanks for the reply.  The documentation for the vpss driver explained all about the output format but it took me a while to figure out how to determine what the pin mux values are set to.  Finally figure it out and noticed that they have indeed been overwritten.  I've been trying to find where this m3 firmware is overwriting the values i set but can't seem to locate it.  Can you tell me where I should be looking?

Thanks,

Rodrigo

Rodrigo,

This is a known issue of the M3 firmware, you can not see it since it is black box. but you can workaround this issue by reconfiguring the pin after loading M3 firmware.

We are working on fix this for the future release

Hope this answers your questions.

Regards,

yihe

Thanks Yihe,

I'm not too sure where the M3 firmware gets loaded so I've been trying to set the pin mux values on the kernel command line but in doing so my device won't even boot.  Where would be a good place to set the values?

Thanks,

Rodrigo

Rodrigo,

M3 firmware is something call ti816x_hdvpss.xem3(PSP) or dm816x_hdvpss.xem3(EZSDK). you can search your file system to see where it is loaded.

do you use PSP directly or use EZSDK? if using PSP only, you can move to PSP 04.00.02.14 or newer release, m3 firmware does not configure the pinmux.

if using EZSDK, you can easily add the pin mux codes into your own kernel module(must be dynamitcally) and load this module after M3 firmware is loaded. For example, if you have kernel module to control the external video device connected to VOUT1, please add the pin mux into that driver.

Regards

yihe

Hi,

Small correction,

echo 0 > /sys/devices/platform/vpss/display0/enabled

echo double/doublediscreted,yuv422spuv > /sys/devices/platform/vpss/display0/enabled

echo 1 > /sys/devices/platform/vpss/display0/enabled

d is by mistake in above command.

Regards,

Hardik Shah