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Adventurer
Adventurer
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Registered: ‎06-22-2018

AXI DMA get data size actually transferred

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I'm using the PS side DMA in Zynq 7020. Becuause my PL side may terminate the transfer earlyer by asserting the TLAST signal. So I want to know when the "XAxiDma_SimpleTransfer()" return, how many bytes it has transferred.

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Explorer
Explorer
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Registered: ‎07-17-2014

Oooo - lucky since you're bare metal. Hahah. It's a little weirder in Linux.

Anyway - did you look at the AXI DMA Datasheet?

There's a register that states how many bytes got sent...

Given that you haven't provided a lot of details -- or shown your implementation...

If you look at register 0x28 -> MM2S_LENGTH or 0x58 -> S2MM_LENGTH

I think those might be what you want. I'm looking at PG021 on PDF page 15/16 (but I'm also looking at the v7.1  Ap1 1, 2015 version. Might be on a different page with a newer verion of the guide.)

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Explorer
Explorer
436 Views
Registered: ‎07-17-2014

Oooo - lucky since you're bare metal. Hahah. It's a little weirder in Linux.

Anyway - did you look at the AXI DMA Datasheet?

There's a register that states how many bytes got sent...

Given that you haven't provided a lot of details -- or shown your implementation...

If you look at register 0x28 -> MM2S_LENGTH or 0x58 -> S2MM_LENGTH

I think those might be what you want. I'm looking at PG021 on PDF page 15/16 (but I'm also looking at the v7.1  Ap1 1, 2015 version. Might be on a different page with a newer verion of the guide.)

View solution in original post