TP2850 de-interlace driver for iMX8MP boards

[FredTsai]

Hi @qiang_li-mpu_se  and @joanxie ,

After referring to the website you provided, there will be a problem that mx8_v4l2_cap_drm_64 cannot be recorded, please help analyze this issue, thank you.

Here is my environment:

HW platform: IMX8MP

Video-In: TP2850

Linux Version: 5.10.52

Android Version: 11

Refer to your previous article on de-interlace:

https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/ISL79987-and-adv7180-de-interlace-driver...

1. Refer to the Patch provided by your article (L5.4.0_2.3.0_ISL7998x_Patch.7z)

2. After unzip, I refer to 0001-ISI-Add-de-interlace-support.patch to Patch to my BSP

3. DTS isi_0 settings are as follows (NTSC weave mode):

4. After applying PATCH, use mx8_v4l2_cap_drm_64 to verify, the result cannot be recorded, it will always stop at (v4l2_device_streamon:1478): channel[0] v4l_dev=0x4 start capturing.

(command: mx8_v4l2_cap_drm_64 -cam 1 -d "/dev/video1" -fmt YUYV -ow 1280 -oh 720 –of)

5. The attached file is the LOG of the video recorded by mx8_v4l2_cap_drm_64, and the ISI0 register has been dumped.

Please help to analyze this issue, thank you.

Thanks

Fred

[qiang_li-mpu_se]

Can you capture the stream to file and attach here?

[FredTsai]

Hi @qiang_li-mpu_se ,

The attached file is the captured stream.

Thanks
Fred

[qiang_li-mpu_se]

I think you can check is there any other interrupt happens in ISI_CHNL_STS register. 

And in isi_capture driver code, is there any code skip some frames. This is BSP version related.

[FredTsai]

Hi @qiang_li-mpu_se ,

As attached file LOG.

CHNL_STS is 0x100.
[ 64.904867][ T1793] mxc-isi 32e00000.isi: CHNL_STS[0x14]: 100

imx8-isi-cap.c: only skip frame once
[ 89.369850][ C0] isi-capture 32e00000.isi:cap_device: Skip frame when buffer number is not match ISI trigger buffer

Do you have any suggestions for DEBUG?

Thanks
Fred

[qiang_li-mpu_se]

These codes should be removed, for de-interlace mode, each buffer will generate two interrupts, so it will not align with buffer buffer number.

[FredTsai]

Hi @qiang_li-mpu_se ,

I have removed these codes, but the output still does not improve.

Remove code: (imx8-isi-cap.c -> mxc_isi_cap_frame_write_done)

output:

Thanks
Fred

[qiang_li-mpu_se]

Please print out the CHNL_STS register value for each interrupt in function mxc_isi_irq_handler():

status = mxc_isi_get_irq_status(mxc_isi);

+ printk("STS = 0x%x.\n", status);

And in mxc_isi_enable_irq() function, you can just enable RCVD interrupt to try:

void mxc_isi_enable_irq(struct mxc_isi_dev *mxc_isi)
{
    u32 val;

    val = CHNL_IER_FRM_RCVD_EN_MASK;
    writel(val, mxc_isi->regs + CHNL_IER);
}

[FredTsai]

Hi @qiang_li-mpu_se ,

The code has been modified as you suggested,

imx8-isi-hw.c

imx8-isi-core.c

Thanks
Fred

[qiang_li-mpu_se]

Bit 17 EARLY_VSYNC_ERR appears in each interrupt, that means before ISI received 720 lines of video, VSYNC appears. So the TP2850 output field data is not 1280*720, you need identify the correct resolution for TP2850, and set it into ISI.

For example, if the TP2850's output is 720*240 field size, and you set 1280*720 in ISI, then you will get current issue, EARLY_VSYNC_ERR appears, and in capture buffer, there is only video data at the start of the buffers.

[FredTsai]

Hi @qiang_li-mpu_se ,

The output of TP2850 is NTSC signal with a resolution of 720x480.
I modified camera_metadata(720X480), but the result is still the same, is there anything else that needs to be confirmed??

The attached file is the camera metadata and the test LOG after modifying the camera metadata.

Thanks
Fred

[qiang_li-mpu_se]

From register "CHNL_IMG_CFG[0x0c]: 2d00500", it is still 1280*720.

[FredTsai]

Hi @qiang_li-mpu_se ,

I use the following command instead, setting the output to 720x480:
mx8_v4l2_cap_drm_64 -cam 1 -d "/dev/video1" -fmt YUYV -ow 720 -oh 480 -of

At this time, the CHNL_IMG_CFG register in the LOG is: 1e002d0 (720x480)

However, this setting will cause the screen to not be recorded. From the LOG, it can be found that it has been stuck in "start capturing".

Thanks
Fred