OMAPL-137 boot up quite slowly from nand-flash

Zhang,

     When you say 'boot time' are you referring to the time it takes for the AIS Image to upload to the device? Or are you referring to the time after the image is uploaded until the program starts execution?

    Also - what does quite slow mean? 10 seconds? 1 minute?

   You may wish to make use of the Debug GEL file to make sure your setting are correct.

Hi Drew

The booting time is the time it takes for the AIS image to be loaded to the device.

For a 60k bytes size image file it takes 12 seconds or so

For a 180k bytes size image file it takes 36 seconds or so.

I  am sure the GEL file setting is correct.

BTW I am using two boards to test these. One board is with OMAPL-137 revision 1.0 and the other board is with OMAPL-137 revision 2.0.

Both the two boards are from the same design. But the board with OMAPL-137 1.0 boot pretty prompt.  

Now I suspect the NAND flash on that board is something wrong..... Am I right?

Thank you for your kind help!

Zhang

Zhang,

The difference between the 1.0 Rev and the 2.0 Rev are specified in the OMAP-L137 Errata.

Hi Drew

I have read that errata but that does not help. :(

The errata said the design exceptions are only exist when the EXTENDED_WAIT_MODE is ON for NAND FLASH

I have checked that during the booting time the EXTENDED_WAIT_MODE is OFF.

Thank you very much.

Zhang

jc said:

If you are concerned with the boot times from your NAND flash, you can enable the PLL and optimize the EMIFA timings using the AISgen tool. That should greatly speed things up for you.

Jeff

Hi Jeff thanks for your suggestion.

The question is why do the two boards with different OMAPL137 have quite different booting time?

The boards with 1.0 OMAPL137 works pretty fine while the 2.0 OMAPL137 boots quite slow. 

For the same AIS image file, one needs 1 second but the other needs 36 seconds.

and they are all use the same default setting for the PLL and EMIFA setting.

Another question is how to setup PLL and EMIFA settting correctly?

Could you give me more detailed suggestion regarding this issue?

Thank you again.

I really appreciate your help

Zhang

jc said:

Changes were made to the WAIT_FOR_READY function in the boot loader. Can you check the WAIT pin on your NAND to make sure it is toggling and not active the entire time?

....

I did check the EMIFA_WAIT0 pin of OMAPL-137 several days ago. It is always keeping high voltage level which is 3.3V.

but I did not check the WAIT pin of the NAND. Aren't they connected together?

I will check it today anyway. thanks

Zhang

I am really happy as the problem has been fixed.

thanks for your kind help

Zhang

Great news. Can you describe what the issue was and how you fixed it, for future reference?

Jeff

jc said:

Great news. Can you describe what the issue was and how you fixed it, for future reference?

Jeff

According to my experience, the OMAPL137 of 1.0 Rev and 2.0 Rev have different default EMIFA settings.

So, when you generate ais image using AISGen, if you choose to not configure the PLL and EMIFA, then the default settings will be applied to the ais image.

This make the uploading procedure quite slow for 2.0 Rev while the procedure is normal for 1.0 Rev.

I by setting the correct PLL and EMIFA parameters successfully make the uploading procedure quick and normal :)

that's all

best regards

zhang