On Thu, Oct 27, 2022 at 11:39:02AM +0200, Lorenzo Pieralisi wrote: > On Thu, Sep 15, 2022 at 09:16:27AM -0500, Rob Herring wrote: > > On Wed, Sep 14, 2022 at 1:24 AM Manivannan Sadhasivam > > <manivannan.sadhasivam@xxxxxxxxxx> wrote: > > > > > > On Tue, Sep 13, 2022 at 03:07:46PM -0500, Bjorn Helgaas wrote: > > > > On Tue, Sep 13, 2022 at 06:00:30PM +0100, Jon Hunter wrote: > > > > > On 13/09/2022 17:51, Manivannan Sadhasivam wrote: > > > > > > On Tue, Sep 13, 2022 at 03:42:37PM +0530, Vidya Sagar wrote: > > > > > > > Some of the platforms (like Tegra194 and Tegra234) have open slots and > > > > > > > not having an endpoint connected to the slot is not an error. > > > > > > > So, changing the macro from dev_err to dev_info to log the event. > > > > > > > > > > > > But the link up not happening is an actual error and -ETIMEDOUT is being > > > > > > returned. So I don't think the log severity should be changed. > > > > > > > > > > Yes it is an error in the sense it is a timeout, but reporting an error > > > > > because nothing is attached to a PCI slot seems a bit noisy. Please note > > > > > that a similar change was made by the following commit and it also seems > > > > > appropriate here ... > > > > > > > > > > commit 4b16a8227907118e011fb396022da671a52b2272 > > > > > Author: Manikanta Maddireddy <mmaddireddy@xxxxxxxxxx> > > > > > Date: Tue Jun 18 23:32:06 2019 +0530 > > > > > > > > > > PCI: tegra: Change link retry log level to debug > > > > > > > > > > > > > > > BTW, we check for error messages in the dmesg output and this is a new error > > > > > seen as of Linux v6.0 and so this was flagged in a test. We can ignore the > > > > > error, but in this case it seem more appropriate to make this a info or > > > > > debug level print. > > > > > > > > Can you tell whether there's a device present, e.g., via Slot Status > > > > Presence Detect? If there's nothing in the slot, I don't know why we > > > > would print anything at all. If a card is present but there's no > > > > link, that's probably worthy of dev_info() or even dev_err(). > > > > > > > > > > I don't think all form factors allow for the PRSNT pin to be wired up, > > > so we cannot know if the device is actually present in the slot or not all > > > the time. Maybe we should do if the form factor supports it? > > > > > > > I guess if you can tell the slot is empty, there's no point in even > > > > trying to start the link, so you could avoid both the message and the > > > > timeout by not even calling dw_pcie_wait_for_link(). > > > > > > Right. There is an overhead of waiting for ~1ms during boot. > > > > Async probe should mitigate that, right? Saravana is working toward > > making that the default instead of opt in, but you could opt in now. > > I read this as "trying to bring the link up is mandatory because > we can't detect an empty slot, therefore ~1ms delay during boot > is unavoidable" and on that Rob's suggestion applies. > Right. Rob's suggestion came as areply to my worry on waiting for link up during boot. > Just to understand where this thread is going. The suggestion > above does not change the aim of this patch, that seems reasonable > to me and it makes sense even if/when what Rob is suggesting is > implemented. > > Is that correct ? > Yes, Rob's suggestion makes sense to me. And it has to be implemented as a separate patch but this patch itself is required to demote the error log to debug. Thanks, Mani > Thanks, > Lorenzo -- மணிவண்ணன் சதாசிவம்
