[U-Boot] Regarding patch: http://patchwork.ozlabs.org/patch/373593/

[Marek Vasut <marex@denx.de>]

On Tuesday, April 07, 2015 at 04:05:31 PM, Ramneek Mehresh wrote:
> > -----Original Message-----
> > From: Marek Vasut [mailto:marex at denx.de]
> > Sent: Tuesday, April 07, 2015 7:22 PM
> > To: Mehresh Ramneek-B31383
> > Cc: u-boot; sr at denx.de
> > Subject: Re: Regarding patch: http://patchwork.ozlabs.org/patch/373593/
> > 
> > On Tuesday, April 07, 2015 at 08:18:03 AM, Ramneek Mehresh wrote:
> > 
> > [...]
> > 
> > > > Hi,
> > > > 
> > > > Is this similar hardware bug to the one which MX6 PCIe is suffering
> > > > ? On MX6, the bug is that you cannot reset the PCIe and PCIe PHY
> > > > from software, which means that if you start PCIe in U-Boot, you
> > > > cannot reliably use it in Linux. Furthermore, if you reset the MX6
> > > > via WDT, you cannot start PCIe reliably in Linux even if PCIe is not
> > > > used in U-Boot at all.
> > > > 
> > > > Is this the same type of hardware screwup where the design team
> > > > didn't think reset was necessary?
> > > 
> > > I have raised request for this feature in up-coming socs, and they
> > > have agreed to provide phy shut-down in future revs. However, this
> > > support is not available in current revs for which the code is sent.
> > > What do you suggest we should do for current socs?
> > 
> > Hi,
> > 
> > I don't know, but doesn't leaving the USB running cause trouble to Linux?
> > I think you should at least document the reasoning why the USB stop is
> > not implemented for this broken hardware.
> 
> Hi Marek, it's not USB controller stop, it's Phy stop which is not
> supported. Controller stopping is supported.

OK, does it pose a problem for Linux ? If not, then please just document
it and let's stick with what there now.

Best regards,
Marek Vasut