Hi,
According Hyperlink data mannual the throughput of hyperlink should be 40gbps with 4 lanes, each of lane configured 10Gbps.
But when i test this throughput with edma cc1, the result is around 20Gbps instead of 40gbps. the test case as below,
1) serdes reference clock: 250Mhz
2) pll mpy is 10x and full speed is configured, so total pll MPY is 40 and frequecy on each lane is 250*40 = 10Gbps.
3) 4 lanes is actived.
3) EDMA cc1, Acnt = 32KB, Bcnt = 100.
then i use edma move 3200KB data from c6670 to a 6678 buffer , which address is mapped into hyperlink space.+
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On 6678 side there is only one task , which detect the last word of the written buffer. Once the last word is written correctly , as means the hyperlink write is complete.
And then this task send an interrupt to 6670 to inform the completion of hyperlink write.
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on 6670 side, in the isr of this interrupt time is record and total writting cost time is caculated.
I'm confused with the throughput of hyperlink since there's no relevant document on this issue and my test result is far from the reference.
Can anyone tell me does this result of 20Gbps make sense or is there any mistake in my testcase??