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<P><FONT SIZE=2>Hi,</FONT>
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<P><FONT SIZE=2>I have couple of questions regarding static rate implementation.</FONT>
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<P><FONT SIZE=2>- In struct ib_ah_attr, static_rate is defined as u8. What are the </FONT>
<BR><FONT SIZE=2> expected values that static_rate is supposed to take ? Is it </FONT>
<BR><FONT SIZE=2> absolute Gb/s ? Gb/s in 2.5Gb/s units ? or relative rate to</FONT>
<BR><FONT SIZE=2> port speed ?</FONT>
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<P><FONT SIZE=2> Looking at ipoib_main I understand that the static_rate is supposed</FONT>
<BR><FONT SIZE=2> to be the relative rate to port speed. In other words, a divider for the </FONT>
<BR><FONT SIZE=2> current port speed.</FONT>
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<P><FONT SIZE=2>- For some reason I don't static_rate initialization for SDP. This should</FONT>
<BR><FONT SIZE=2> either be in SDP code or in the CM (cm_init_qp_rtr_attr()).</FONT>
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<P><FONT SIZE=2>- In mthca, there are two places setting up the static_rate. One</FONT>
<BR><FONT SIZE=2> for AH which looks fine. The other one for QP which I believe has</FONT>
<BR><FONT SIZE=2> a bug.</FONT>
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<P><FONT SIZE=2> mthca_qp.c:</FONT>
<BR> <FONT SIZE=2>qp_context->pri_path.static_rate = (!!attr->ah_attr.static_rate) << 3;</FONT>
<BR><FONT SIZE=2> Should be </FONT>
<BR> <FONT SIZE=2>qp_context->pri_path.static_rate = (!!attr->ah_attr.static_rate);</FONT>
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<P><FONT SIZE=2> Because max_stat_rate is bits 10:3 at offset 8h of Address Path.</FONT>
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<BR><FONT SIZE=2>- A question for next generation HW. Would you find it more useful that the </FONT>
<BR><FONT SIZE=2> HCA supports static rate as an absolute speed (Gb/s) or as a relative ratio to</FONT>
<BR><FONT SIZE=2> the current port speed ?</FONT>
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<P><FONT SIZE=2>Thanks</FONT>
<BR><FONT SIZE=2>Dror</FONT>
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