On Tue, Apr 23, 2019 at 02:58:13PM +0530, Manikanta Maddireddy wrote: > PCIe link up fails with few legacy endpoints if root port advertises both > Gen-1 and Gen-2 speeds in Tegra. This is because link number negotiation > fails if both Gen1 & Gen2 are advertised. Tegra doesn't retry link up by > advertising only Gen1. Hence, the strategy followed here is to initially > advertise only Gen-1 and after link is up, retrain link to Gen-2 speed. > > Tegra doesn't support HW autonomous speed change. Link comes up in Gen1 > even if Gen2 is advertised, so there is no downside of this change. > > This behavior is observed with following two PCIe devices on Tegra, > - Fusion HDTV 5 Express card > - IOGear SIL - PCIE - SATA card > > Signed-off-by: Manikanta Maddireddy <mmaddireddy@xxxxxxxxxx> > --- > V2: Updated commit log to reflect why this issue is observed on Tegra with > these particular cards > > drivers/pci/controller/pci-tegra.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) Acked-by: Thierry Reding <treding@xxxxxxxxxx>
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