How to know if CX3 recongizes MIPI CSI-2 clock?

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Anonymous
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I'm working with a custom camera frontend that does not follow MIPI-DPHY spec exacty on the clock lane.

   

The clock lane of this camera does not have HS-ZERO in its LP-HS transition.

   

The clock is continuous clock mode: LP-HS transition only happen once, clock does not switch back to LP between lines or frames.

   

Questions:

   

1) Can CX3 recognize this non-standard clock lane? (NXP IMX6Q SoC can recognize it)

   

2) How do I check the status of clock lane? (How do I know whether the clock is recognized by CX3 or not?)

   

    Currently I can get the camera frontend to transimit MIPI data, but I don't get the DMA callback on the CX3 side. I don't get any MIPI errors from CyU3PMipicsiGetErrors(). I'm suspecting the clock lane is not recognized by CX3. I want to confirm this. Is there a register that reports this?

   

3) It it possible to always run the clock lane always in HS mode?

   

    For NXP IMX6Q SoC, I must reset the MIPI DPHY when the clock lane is LP, then do LP-HS transition, then the SoC will recognize MIPI clock. If I reset MIPI DPHY with the clock already in HS mode, then it won't see the clock at all.

   

    Is it also the case for CX3?

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1 Solution
Keerthy_V
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Hello,

   

 

   

CX3 support both gated clock mode and continuous clock mode. For supporting the continuous clock mode you have to make some modifications in the CX3 firmware which is documented in the kba91295.

   

http://www.cypress.com/knowledge-base-article/cx3-hardware-frequently-asked-questions-kba91295

   

Please refer question no:13.

   

 

   

Regards,

   

Keerthy

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3 Replies
Keerthy_V
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First like given 250 sign-ins 50 solutions authored

Hello,

   

 

   

CX3 support both gated clock mode and continuous clock mode. For supporting the continuous clock mode you have to make some modifications in the CX3 firmware which is documented in the kba91295.

   

http://www.cypress.com/knowledge-base-article/cx3-hardware-frequently-asked-questions-kba91295

   

Please refer question no:13.

   

 

   

Regards,

   

Keerthy

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Anonymous
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I know CX3 support continuous mode, but like I asked in my 3rd question, I'm wondering if CX3 need the initial LP-HS transition to activate the clock receiver.

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Dehuan Xin,

if the clock is in continuous clock mode, LP-HS transition only happen once, clock does not switch back to LP between lines or frames.

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