• Resolved

Not seeing expected frame rate on sensor attatched to CSIA on 4460

We are using a 4460 with an OV5640 sensor attached to CSIA and are not seeing the expected frame rate.  Even when I increase the speed of the MIPI clock I do not see a change in the frame rate.  First,  I would like to verify that we are programming the PLLs in the sensor correctly to achieve the expected frame rate but I'm not sure how to make that calculations.

  I am capturing YUV 422(2 bytes per pixels), VGA data using 2 MIPI data lanes.  If I want to capture 30fps, what is the clock speed should I see if I measure it on the MIPI clock lane?

  Second, can somebody tell me what the DDRCLK is when reference in the TRM in regards to how to program the ths_term and ths_settle fields in the CSI2 Phy REGISTER0 register.  The TRM makes these references

ths_term = ceil(12.5 / DDR clock period) –1
ths_settle = ceil(90 ns / DDR clock period) + 3

thank you,


  • Hi Jeff,

    Can you please tell me which kernel release you are using ? Is it V4L2 based capture ?

    What is the frequency from OV5640 sensor, which you see when you probe the clock lane ?

    What value do you see in ov5640_s_fmt() function for ov5640->pixel_rate->cur.val64 variable ?

    If you are using V4L2 based kernel, can you tell me what is the value of DDR clock frequency ?

    Please refer to omap4iss_csiphy_config function of "drivers/media/video/omap4iss/iss_csiphy.c" for the calculation.


  • In reply to sweta bhatt:


      Yes, doing v4l with a 2.6.30 kernel.  The mipi_pclk is 112000000(this is the value returned by get_pclk) so what I see on the bus is 56000000.  The cur.val64 is 7000000 and the ddr_clk is 28000.  This is for 16bit per pixel VGA using 2 data lanes.


  • In reply to Jeff Hane1:

    which sensor are you using and have you verified that the sensor is outputting at 30fps?

  • In reply to Mayank Mangla:

    OV5640.   We can't access the h/v sync pins on the sensor so cannot verify it on the sensor.  That's why I'm trying to determine if the mipi clock is running fast enough to achieve the data rate I want.  If yes, then I can look at other possibilities. 

  • In reply to Jeff Hane1:

    A rough calculation says you need at least 73MHz MIPI clock for VGA 30, 16bpp. This is assuming no H and V blanking, The clock you have set is too low.

  • In reply to Mayank Mangla:

    I got some feedback from the sensor vendor and have modified the registers settings such that the clock rate is 114MHz.   However, on the OMAP's side it seems to think it is running at 15fps.  We are not dropping any incoming frames in the driver.  When I get back in the office I will connect a scope to a gpio that is being toggled in the CSI's ISR to actually measure what the chip is seeing.   Is there anything that I should be looking at to determine why I am not getting the expected frame rate?

  • In reply to Jeff Hane1:

    Please validate frame rate using the scope. From SW standpoint here is something you can try:

    1. Run camera_test from /system/bin. Usage is camera_test f

    2. Press 'E' to print capabilities. Make sure that 30fps is supported.

    3. If supported, adjust camera fps range to [30, 30] and start preview using camera_test menu options.

    4. Measure the frame rate

  • In reply to Mayank Mangla:

    Just to clarify.  Is camera_test an android/openMAX application? Is the source for this somewhere in android tree?

    thank you,


  • In reply to Jeff Hane1:

    It is a native (C++) app which uses Android CameraService APIs just like an android app will do. It is a little easier to debug and modify than Java code.

    You can find the source in the folder hardware/ti/omap4xxx/test/CameraHal/

  • In reply to Mayank Mangla:

    I am unable to run the camera test:

    /system/bin/camera_test -f                    
    Unable to connect to CameraService
    Giving up!!
    Camera initialization failed
    Application closed after: 1014502 ms

    I'm guessing this is because of these android logs:

    logcat -d |busybox grep -i camera
    I/CameraService(  108): CameraService started (pid=108)
    E/CameraHal(  108): (40079630)   hardware/ti/omap4xxx/camera/OMXCameraAdapter/OMXDCC.cpp:99 initDCC - No DCC files found, switching back to default DCC
    E/CameraHal(  108): (40079630)   hardware/ti/omap4xxx/camera/OMXCameraAdapter/OMXDCC.cpp:44 loadDCC -  Error in DCC Init
    E/CameraHal(  108): (40079630)   hardware/ti/omap4xxx/camera/BaseCameraAdapter.cpp:2682 CameraAdapter_Capabilities - supportedCameras= 0
    E/CameraHal(  108): (40079630)   hardware/ti/omap4xxx/camera/CameraProperties.cpp:108 loadProperties - camera busy. properties not loaded. num_cameras = 0
    E/CameraHal(  108): (40079630)   hardware/ti/omap4xxx/camera/CameraHal_Module.cpp:750 camera_get_number_of_cameras - Unable to create or initialize CameraProperties
    W/PackageManager(  280): Package com.ti.omap4.android.camera desires unavailable shared library com.google.android.media.effects; ignoring!
    E/CameraService(  108): CameraService::connect X (pid 805) rejected (invalid cameraId 0).
    E/CameraService(  108): CameraService::connect X (pid 805) rejected (invalid cameraId 0).
    E/CameraService(  108): CameraService::connect X (pid 818) rejected (invalid cameraId 0).

    And the ducati logs indicate that it is looking for a OV5650:

    [      0.884] [ERR=22] src/sensor_detect_MSP.c:[303]:0>>:OV5650 Socket:0

    and since we are using a 5640 there is no sensor detected.   There is a OV5640 driver in the ducati source so I don't understand why it does not see it.  We are using the pre-built ducati firmware that comes with the 4AJ.2.1 release:

    [      0.000]  ***DUCATI VERSION INFO***
    [      0.000] Compile DATE Sep 27 2012 TIME 16:29:43
    [      0.000] GIT ducati_mmlegacy
    [      0.000]     BRANCH:(no branch) TAG:TI-MM-DUCATI_RLS_2.x.15.2
    [      0.000]     COMMIT-ID:36d0068