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Date: Thu, 14 Mar 2024 21:58:11 +0000 (GMT)
From: "Maciej W. Rozycki" <macro@orcam.me.uk>
To: =?UTF-8?Q?Ilpo_J=C3=A4rvinen?= <ilpo.jarvinen@linux.intel.com>
cc: Bjorn Helgaas <bhelgaas@google.com>, linux-pci@vger.kernel.org, 
    LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/1] PCI: Use the correct bit in Link Training not active
 check
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On Thu, 14 Mar 2024, Ilpo Järvinen wrote:

> One more point to add here, I started to wonder today why that use_lt 
> parameter is needed at all for pcie_retrain_link()?
> 
> Once the Target Speed has been changed to 2.5GT/s which is what the quirk 
> does before calling retraining, LT too should work "normally" after that.

 We don't know if the link is going to become stable with the TLS update 
to 2.5GT/s and we want to ensure that the link has reached the active 
state before claiming victory; LT clear does not mean the link is active, 
it only means what it means, that is that the link isn't being trained at 
the moment.

 Also we don't want to reset the TLS to the maximum before the link has 
become active.

 Does this answer your question?

  Maciej