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Hi,<br>
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<pre wrap="">I am debugging the DMA bug now. and I will send it out when i fix it.
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<pre wrap="">What sort of DMA bug?
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<pre wrap="">The DMA may time-out. :(
The DMA time-out may occur in two situations:
[1] send a command DMA descriptor, see the nfc->send_command() function.
[2] read the non-ecc data from nand, see the nfc->read_data() function.
I don't know why. Maybe caused by the timing, or something else.
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<pre wrap="">I am confused. The send-command DMA timeout prevents any write for me.
You guys surely would have noticed if you have been bitten as well. Does
it depend on the NAND chip?
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<pre wrap="">I think It does not depend on the NAND chip.
My test chip is Samsung K9G8G08U0M.
Sometimes, I can run a long time while there is no DMA timeout occurring;
Sometimes, the bug appears right away.
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For me, the bug always happens right away. So, if you need logs or debug
output or can give me a pointer into some direction, I am glad to
assist.
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Thanks a lot. :)<br>
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I am trying to merge the two DMA descriptors into one in the
send_command().<br>
The original bsp code used only one DMA descriptor.<br>
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Huang Shijie<br>
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