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PCIe already >>> has 2x lanes as a standard feature, so this naming is a bit confusing. >>> It's not like dual-LVDS display in which LVDS is only a single lane. >> >> I suggested the "2-lane" and "x2" terminology because I assumed the >> result is what the PCIe spec would describe as a "x2 Link" consisting >> of two Lanes. >> >> If that's not the case, maybe "cross-controller lane-bonding mode" or >> "lane stealing" would be more accurate, but I don't know what those >> mean, so if we use them I would also like to know what the result >> looks like in standard PCIe terms. >> > > Mhhh I don't really like the term lane stealing. Also cross-controller > lane-bonding > might be a first. Even if correct it would complicate identification > of the feature > that at the end of the day configures the HW to provide a 2 lanes PCIe. > > Consider that in such mode, the other PCIe controller gets disabled (this is > handled in DT) so it's effectively enabling the standard PCIe 2x lanes > and apply the HW configuration for it. > >>>> SoC. This is needed for correctly functionality of Eagle WiFi Card >>>> normally attached to this SoC that require a 2-line PCIe card to >>>> correctly work (and give the proper performance) >>>> >>>> The first 2 patch address a limitation of the PCIe implementation >>>> where the PERSTOUT reset were indirectly asserted and deasserted >>>> all at the same time (for all the 3 PCIe card) with PCIe >>>> enable and disable. >>>> The 2 patch address this and introduce correct reset to control >>>> reset line for the relevant PCIe line. >>>> >>>> The last 2 patch add additional logic and support to assert >>>> and deassert the PERSTOUT and also apply the required configuration >>>> for 2-lanes mode. >>>> >>>> 2-lanes mode is implemented in DT by adding the required property >>>> and by defining the "num-lanes" to 2. > Hi. Isnt this just pcie bifurcation? Logically bifurcation would need to be disabled when using 2 lanes in one slot and enabled when 2 lanes are split between 2 pcie slots. But I'm not really sure what value a bifurcation property would add. Isnt the current schema enough? The mt7987 will need the same logic as it can also bifurcate one pcie slot. MvH Benjamin Larsson