On Tue, 13 Mar 2018 17:27:21 +0200
Mathias Nyman <mathias.ny...@linux.intel.com> wrote:
> Example for clarification:
> Gen 1x1 = 5Gbps, SuperSpeed, one lane, same as USB3.0, and USB 3.1 Gen1
> Gen 2x1 = 10Gbps, SuperSpeedPlus, one lane, same as USB 3.1 Gen2
> Gen 1x2 = 10Gbps, SuperSpeed, Dual-lane (2 x 5Gbps)
> Gen 2x2 = 20Gbps, SuperSpeedPlus, Dual-lane (2 x 10Gbps)
> 4. Should the "speed" sysfs entry be more accurate? USB 3.1 and later
> can list different supported lane speeds other than the 5Gbps or 10Gbps.
> actual port speed would be lane count * current lane speed in use.
> Or do we just keep it simple and show the maximum signaling
> rate * lane count, i.e. 5000, 10000 or 20000?
> and show "SSIC" instead of "Gen XxY" for asymetric lane SSIC devices,
> skipping details on rx and tx lane counts.
Please do not compute "signaling rate * count", because it is very misleading
and that value cannot be used to verify whether the hardware works at its
maximum available speed or not.
Gen 1x2 is not 5 * 2 = 10 Gbps, but only 8 Gbps (like Gb Ethernet is 1 Gbps,
not 1.25 Gbps), while Gen 2x1 is very close to 10 Gbps, i.e. significantly
faster (due to a different encoding), so it would be wrong to display them as
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