SK-AM62P-LP: How to enable BT656 support on AM62P ?

Dear DRM expert,

   I enabled the BT656 in register level in tidss source code, we can the displace change as below,

    /resized-image/__size/1080x240/__key/communityserver-discussions-components-files/791/evm_5F00_bt656_5F00_enable.jpg

    After disabling it, then display normally. 

   /resized-image/__size/1080x960/__key/communityserver-discussions-components-files/791/evm_5F00_normal.jpg

   Customer has the sync the code accordingly. 

    Below is the customer issue log.

   /cfs-file/__key/communityserver-discussions-components-files/791/Longhorn_5F00_bt656.txt

   We can see the crts state is Null. Currently, the DTS need to update, such as the DPI output change from sii902 to SERDES and enable the VP port CSC module to covert the RGB888 to YUV422 format.  

     Thanks.

Best regards,

Linjun

Hi Linjun,

Can you please share the changes you did in your experiment.

I just add the code as below in bold line.

static void dispc_vp_init(struct dispc_device *dispc)
{
unsigned int i;

dev_dbg(dispc->dev, "%s()\n", __func__);

/* Enable the gamma Shadow bit-field for all VPs*/
for (i = 0; i < dispc->feat->num_vps; i++) {
VP_REG_FLD_MOD(dispc, i, DISPC_VP_CONFIG, 1, 2, 2);
/* Selects BT-656 format on the VP output */
VP_REG_FLD_MOD(dispc, i, DISPC_VP_CONFIG, 1, 20, 20);
}
}

obviously, we need to change the dss bridge of DTS tree for the next step.  Could you please help?

My purpose is the DPI port output BT656 format data directly.  So, the video port needs to enable the csc function.

Hi Divyansh,

  I add the source code I changed here. It doesn't work.

/cfs-file/__key/communityserver-discussions-components-files/791/bt656.patch 

Need team help do further fix.  Thanks.

Linjun

Thanks Linjun,
Summarizing our offline discussion here. Customer has the following setup:
DPI port -> Serdes (MAX96755) -> Duxin Box -> Windows App
Targeted resolution is 720x480.

Please additionally share these details:
1. Targeted fps (frames per second)
2. What kind of frame output is expected? progressive or interlaced?
3. Please share the timing parameters (in a datasheet) that must be used to configure the DPI output.

Dear Divyansh,

      Here are two requirements from customer for two different project.

1. cluster display

        CVBS resolution ： 720*480 NTSC 60fps  Interlaced output

        Timing ：

         19，3

         20，3

          276，1

          FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT 

          FB_VMODE_INTERLACED

          FB_MODE_IS_DETAILED

     2 IVI display

          DPI  BT656 1920*720  30fps

     To the second case of  display resolution  1920*720, as to the clock isn't standared BT656 spec, could you please evaluate it's possible or not.

Linjun