Support for 1360x768@60Hz resolution/refresh rate

justiceiro

The title explains itself, I think. My tv only support this resolution for 60fps, and when i try to use the 720p option, it doesn't work ( i get  various images like a ghost). The high resolution don't render and i have to use the fit option, what make the screen looks like a SD television. Pls help.

justiceiro

jernej replied at 2016-6-14 02:29
Create patch similar to this: https://github.com/igorpecovnik/lib/blob/master/patch/kernel/sun8i-def ...

Sorry, it had to be done. I will try to work out everything, but i have some questions.

I will need to erase the old image on the card, or i can just update it?
I need a second computer to do it all, ritgh?
Do i need a linux distro to build the image? Or can i use windows?
Wich other tolls i will need? git? gcc?
Thanks in advance, and sorry for the ignorance.
EDIT: Last question: which name convention you are referring too?

jernej

You don't need to erase it, just update with tar file as described in FAQ topic. I don't think it could be build on windows. You can use ubuntu in virtualbox for example. For starters, you need git, make and gcc. Check FAQ topic how to clone and run the build. Build system will check for all required tools and install the missing ones. First build will take very long time, at least 2 hours, but every next build will be in minutes.

I meant that your patch file have to be named something like "linux-0XX-description-of-the-change.patch"

Xer0

same here, this would be very nice!

jernej

Due to unknown reason, Allwinner just hardcoded few standard resolutions instead of making calculations. If someone comes up with required numbers for this resolution, I can add them, but otherwise I will not work on this.

justiceiro

jernej replied at 2016-6-12 18:01
Due to unknown reason, Allwinner just hardcoded few standard resolutions instead of making calculati ...

I think i can do those calculations. I just need some guidance. Point me out the part of the code that i should analyze and i will work on it.

jernej

justiceiro replied at 2016-6-12 18:03
I think i can do those calculations. I just need some guidance. Point me out the part of the code ...

The table is here: https://github.com/jernejsk/linu ... /aw/hdmi_core.c#L26

I'm really not sure how timings are calculated. Linux-sunxi community managed to identify HDMI controller: https://linux-sunxi.org/DWC_HDMI_Controller According to them, you have to download i.MX6 Reference manual and check section 33 which talks about HDMI controller.

justiceiro

jernej replied at 2016-6-13 03:37
The table is here: https://github.com/jernejsk/linu ... /aw/hdmi_core.c#L26

I'm really not sure ho ...

From what i understood, it seem more that the hdmi resolution are limited for the hdmi standard. This is why he hardcoded: he simplied copied from the standard.

Not that there is no way make adjustments to non tradicional resolution, but it's not trivial. Besides, since its not a standard, there is a chance of diferent parameter for different monitor models. Anyway, a  good article in the subject can seen here:
https://software.intel.com/en-us ... -on-intel-graphics/

He explain each parameter, but some "translation" is needed.

he calls the parameters
hActive
hBlank
hSync_offset
hSync_widt
vActive
vBlank
vSync_offset
vSync_width
using the dtd calculator(he mentions in the article), its possible to see the standard values and from there, compare with the ones in the source that you pointed out.

The first, called VIC, is.... whatever, just put 0 on it anyway
the second, PCLK = pixel clock
AVI_PR, only for avi resoltution it seems
X = width
Y=Heigth
now its gets interisting
HT = hActive + hBlank
HBP = hBlank - hSync_offset - hSync_width
HFP = hSync_offset
HST =  hSync_width
VT = vActive + vBlank
VBP = vBlank - vSync_offset - vSync_width
VFP = vSync_offset
VST = vSync_width

v_pol and h_pol= no idea ... but its 1 for almost everything.

int  =intercaleted
vac = some kind of angle for 3D images, i think
trd =  only active on 3D images, also.

I will search about those details in my television(samsung btw) and them provide to you. I have 2 TV from differente models from sansung, wich the 1360 is the maximun, so i will try in the 2 of them , so maybe at least the samsung models will be a given

justiceiro

So, it seems that my televisor doesn't has one modeline lying around. Howerver, at least i found a calculator here:
http://arachnoid.com/modelines/
It gave me the output :

1. # 1360x768 @ 60.00 Hz (GTF) hsync: 47.70 kHz; pclk: 84.72 MHz
   
2. Modeline "1360x768_60.00" 84.72 1360 1424 1568 1776 768 769 772 795 -HSync +Vsync

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But, i got a modeline for the maximum 60 fps resolution of my other monitor

1. Modeline............... "1366x768" 85,500 1366 1436 1579 1792 768 771 774 798 +hsync +vsync

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So, which one is the correct?
...
...
...
Know what? Why don't we just put them both in there and just test for ourselves?

Lets do it so. If my calculations are correct, you should include the following lines:

1. 
   
2. {HDMI1360P_60, 0,84720000, 0, 1360, 768, 1776, 352, 64, 144, 795, 26, 1, 3, 0,  1,  0,  0,  0},
   
3. {HDMI1366P_60, 0,85500000, 0, 1366, 768, 1792, 356, 70, 143, 798, 27, 3, 3, 1, 1, 0, 0, 0},

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it seems also that i overcomplicated the calculation a bit up there. But anyway, now what, how can i test this?

jernej

Create patch similar to this: https://github.com/igorpecovnik/ ... obodis-initia.patch against this linux tree: https://github.com/jernejsk/linux Then clone my OpenELEC repo and put patch in projects/H3/patches/linux and follow same file name convention. Then build the image and change script.bin to new resolution. If all goes well, you will see at least proper OpenELEC splash screen. I think Kodi should work too, but I'm not completely sure.