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Hyperlink test with "hyplnk_K2KC66BiosExampleProject" in pdk_keystone

Hi,

We have a problem about hyplnk_C66BiosExampleProject working.

Firstly we tried this example with LOOPBACK mode single dsp.
We think "dataBuffer" is the adress of remote side and "bufferThroughHypLnk" is hyperlink databuffer(00 4000 0000 - 00 4FFF FFFF). Is it ture ?
When we write a value to dataBuffer, immediately same value is written to hyperlink databuffer(00 4000 0000 address). Is it loopback value(at 4000 0000 address ) that
return from remote device or prepared value for send to remote device ? We cant understand loopback is done succesfully?


Also

When we try this example for two dsps, we think there is no data exchange. Our work flows written in below;

1. connect two dsps
2. we change data that will be sent by hyperlink at two core for understand incoming data from where.
3. Close LOOPBACK mode
4. Load example to dsps

When we control the Hyperlink data buffer with emulator, there is no exchange between two cores. Also we cant see any differance between LOOPBACK is open or close cases.
Are there any different configuration for data exchange between two cores ?

Secondly if we load same example to dsps, how can we understand which one is master and which one is slave?

Lastly, There are some variable that we cant understand completely. Could you explain that variable?

local->srcLoc2Rem
local->srcRem2Loc
local->dstLoc2Rem
local->dstRem2Loc

remote->srcLoc2Rem
remote->srcRem2Loc
remote->dstLoc2Rem
remote->dstRem2Loc

Thanks

  • Hi,

    Yes, your understanding is correct. Take a look at "hyplnkExampleIOCycle" function for understanding read/write operation for local/remode side.

    HyperLink has internal state machines to automatically manage the flow control and power saving based on the sideband signals without any software intervention. Flow control is managed independently on a per-direction basis. The RX side sends the throttle signals to the TX side.

    These variables are used for remode/local source and destination translation.

    Thanks,

  • Hi 

    Thanks for your reply 

    I have another question about hyperlink througput performance.

    I am using Hyperlink at 6.25Gbpsx4 lanes and I use EDMA for data transfer.

    I have read HyperLink_Programming_and_Performance_consideration.pdf document. Hyperlink is tested at 10Gbps with 4 lane. In this document, at test with EDMA, thorougput is 3584MB/s.

    So, because of that I use Hyperlink at 6.25Gbpsx4lanes, my througput should be nearly 1600-1700Gbps. But my througput is nearly 1200Gbps.

    Do you have any suggestion about this problem?

    Thanks

  • Hi,

    Hyperlink throughput will be effect, If the trace length is too long.

    How long is the hyperlink cable.Hyperlink shows max throughput when the trace is < 4 inches.

    Thanks,