Linux/AM5728: VIN4A I/O timing modes issue

boycchi

Part Number: AM5728

Tool/software: Linux

Hi all,

We've made a custom board used for dual video capture(vin3a and vin4a).We use the IOSET4 for vin3a and IOSET3 vin4a,however,the quality of the video is different between that two.Vin3a is ok but vin4a is not so good with the green dot(the picture is attached here).After doing some test,I found it may be IO timing's problem.I check the and realized that I should configure the right A_DELAY and G_DELAY value according to the timing mode.I've tried the VIP2_4A_IOSET3_MANUAL1 and VIP2_4A_IOSET3_MANUAL2 but didn't solve my problem.I also tried to move the right iodelay cfg of the vin3a in 7851.mux_data.h,it shows the same question like vin4a.

So,how could i configure the right value of A_DELAY and G_DELAY?Is there anything change i should make according to our own designed board.

Any insight on this will be helpful,sorry for my bad English,if any expression of mine confuse you just let me clarify.

over 7 years ago

0 Biser Gatchev-XID over 7 years ago

TI__Guru**** 393215 points

The factory team have been notified. They will respond here.

0 boycchi over 7 years ago in reply to Biser Gatchev-XID

Expert 1005 points

Hi Biser,
Could u notified the factory tean again?Thanks

0 Yordan Kovachev over 7 years ago

TI__Guru**** 161600 points

Hi,

The A_DELAY and G_DELAY are per IO TIMING mode. For example in the above table, if you click on the VIP1_MANUAL1 link it will take you to Table 7-7. Manual Functions Mapping for VIP1, which lists the corresponding A_DELAY & G_DELAY for VIP1 pins configured in VIP1_MANUAL1 mode. Other values of A_DELAY and G_DELAY are NOT supported.

The Timing values calculations are performed as per the equations given in Section 18.4.6.1.6 Manual IO Timing Modes of AM572x Technical Reference Manual. After calculating the Manual IO Timing Modes values you should write them to the corresponding CFG_x_IN, CFG_x_OUT and CFG_x_OEN registers.

I strongly advise NOT to calculate the IO Timings by yourself. Use the Pinmux tool instead:
www.ti.com/.../pinmuxtool

The values produced from the pinmux tool should be set in the dts file in your Linux SDK.

Best Regards,
Yordan

0 boycchi over 7 years ago in reply to Yordan Kovachev

Expert 1005 points

Hi,
I've tried the value produced from the pinmux tool which is same in the AM572x Sitara™ Processors Silicon Revision 2.0(SPRS953C),and my problem still remain,you said set the value in dts file,I want to know is that mux_data.h file change the I/O timing or other dts file does?

0 Yordan Kovachev over 7 years ago in reply to boycchi

TI__Guru**** 161600 points

Ok, yes you can use the u-boot/board/ti/am57xx/mux_data.h file to set the IO delays in the corresponding iodelay_cfg_entry structure.
You can also use the kernel dts file, located in arch/arm/boot/dts/

Best Regards,
Yordan

0 boycchi over 7 years ago in reply to Yordan Kovachev

Expert 1005 points

Thanks,it seems that the problem is solved

0 Yordan Kovachev over 7 years ago in reply to boycchi

TI__Guru**** 161600 points

Hi,

Can you click the "This resolved my issue button" ?

Best Regards,
Yordan

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Linux/AM5728: VIN4A I/O timing modes issue