On Fri, Jun 21, 2024, Greg KH wrote:
> On Fri, Jun 21, 2024 at 06:20:38AM +0000, Thinh Nguyen wrote:
> > On Fri, Jun 21, 2024, Greg KH wrote:
> > > On Fri, Jun 21, 2024 at 05:42:42AM +0000, Thinh Nguyen wrote:
> > > > On Fri, Jun 21, 2024, Greg KH wrote:
> > > > > On Fri, Jun 21, 2024 at 09:40:10AM +0800, joswang wrote:
> > > > > > On Fri, Jun 21, 2024 at 1:16 AM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > > > > > >
> > > > > > > On Wed, Jun 19, 2024 at 07:45:29PM +0800, joswang wrote:
> > > > > > > > From: Jos Wang <joswang@xxxxxxxxxx>
> > > > > > > >
> > > > > > > > This is a workaround for STAR 4846132, which only affects
> > > > > > > > DWC_usb31 version2.00a operating in host mode.
> > > > > > > >
> > > > > > > > There is a problem in DWC_usb31 version 2.00a operating
> > > > > > > > in host mode that would cause a CSR read timeout When CSR
> > > > > > > > read coincides with RAM Clock Gating Entry. By disable
> > > > > > > > Clock Gating, sacrificing power consumption for normal
> > > > > > > > operation.
> > > > > > > >
> > > > > > > > Cc: stable@xxxxxxxxxxxxxxx
> > > > > > > > Signed-off-by: Jos Wang <joswang@xxxxxxxxxx>
> > > > > > >
> > > > > > > What commit id does this fix? How far back should it be backported in
> > > > > > > the stable releases?
> > > > > > >
> > > > > > > thanks,
> > > > > > >
> > > > > > > greg k-h
> > > > > >
> > > > > > Hello Greg Thinh
> > > > > >
> > > > > > It seems first begin from the commit 1e43c86d84fb ("usb: dwc3: core:
> > > > > > Add DWC31 version 2.00a controller")
> > > > > > in 6.8.0-rc6 branch ?
> > > > >
> > > > > That commit showed up in 6.9, not 6.8. And if so, please resend with a
> > > > > proper "Fixes:" tag.
> > > > >
> > > >
> > > > This patch workarounds the controller's issue.
> > >
> > > So it fixes a bug? Or does not fix a bug? I'm confused.
> >
> > The bug is not a driver's bug. The fix applies to a hardware bug and not
> > any particular commit that can be referenced with a "Fixes" tag.
>
> So it's a bug that the kernel needs to work around, that's fine. But
> that implies it should go to "all" stable kernels that it can, right?
Yes. That's right.
>
> > > > It doesn't resolve any
> > > > particular commit that requires a "Fixes" tag. So, this should go on
> > > > "next". It can be backported as needed.
> > >
> > > Who would do the backporting and when?
> >
> > For anyone who doesn't use mainline kernel that needs this patch
> > backported to their kernel version.
>
> I can not poarse this, sorry. We can't do anything about people who
> don't use our kernel trees, so what does this mean?
Sorry, I wasn't being clear. What I meant is that it needs some work to
backport to stable version prior to v6.9. Anyone who needs to backport
this prior to this will need to resolve these dependencies.
>
> > > > If it's to be backported, it can
> > > > probably go back to as far as v4.3, to commit 690fb3718a70 ("usb: dwc3:
> > > > Support Synopsys USB 3.1 IP"). But you'd need to collect all the
> > > > dependencies including the commit mention above.
> > >
> > > I don't understand, sorry. Is this just a normal "evolve the driver to
> > > work better" change, or is it a "fix broken code" change, or is it
> > > something else?
> > >
> > > In other words, what do you want to see happen to this? What tree(s)
> > > would you want it applied to?
> > >
> >
> > It's up to you, but it seems to fit "usb-testing" branch more since it
> > doesn't have a "Fixes" tag. The severity of this fix is debatable since
> > it doesn't apply to every DWC_usb31 configuration or every scenario.
>
> As it is "cc: stable" that implies that it should get to Linus for
> 6.10-final, not wait for 6.11-rc1 as the 6.11 release is months away,
> and anyone who has this issue would want it fixed sooner.
>
> still confused,
>
Ok. I may have misunderstood what can go into rc2 and beyond then. If we
don't have to wait for the next rc1 for it to be picked up for stable,
then can we add it to "usb-linus" branch?
There won't be a Fixes tag, but we can backport it up to 5.10.x:
Cc: <stable@xxxxxxxxxxxxxxx> # 5.10.x: 1e43c86d: usb: dwc3: core: Add DWC31 version 2.00a controller
Cc: <stable@xxxxxxxxxxxxxxx> # 5.10.x
This can go after the versioning scheme in dwc3 in the 5.10.x lts. I did
not check what other dependencies are needed in addition to the change
above.
Thanks,
Thinh
