RE: [RFC net-next] net: stmmac: should not modify RX descriptor when STMMAC resume

[Joakim Zhang <qiangqing.zhang@nxp.com>]

Hi Jakub,

> -----Original Message-----
> From: Jon Hunter <jonathanh@nvidia.com>
> Sent: 2021年5月7日 22:22
> To: Joakim Zhang <qiangqing.zhang@nxp.com>; Jakub Kicinski
> <kuba@kernel.org>
> Cc: peppe.cavallaro@st.com; alexandre.torgue@foss.st.com;
> joabreu@synopsys.com; davem@davemloft.net;
> mcoquelin.stm32@gmail.com; andrew@lunn.ch; f.fainelli@gmail.com;
> dl-linux-imx <linux-imx@nxp.com>; treding@nvidia.com;
> netdev@vger.kernel.org
> Subject: Re: [RFC net-next] net: stmmac: should not modify RX descriptor when
> STMMAC resume
> 
> Hi Joakim,
> 
> On 06/05/2021 07:33, Joakim Zhang wrote:
> >
> >> -----Original Message-----
> >> From: Jon Hunter <jonathanh@nvidia.com>
> >> Sent: 2021年4月23日 21:48
> >> To: Jakub Kicinski <kuba@kernel.org>; Joakim Zhang
> >> <qiangqing.zhang@nxp.com>
> >> Cc: peppe.cavallaro@st.com; alexandre.torgue@foss.st.com;
> >> joabreu@synopsys.com; davem@davemloft.net;
> mcoquelin.stm32@gmail.com;
> >> andrew@lunn.ch; f.fainelli@gmail.com; dl-linux-imx
> >> <linux-imx@nxp.com>; treding@nvidia.com; netdev@vger.kernel.org
> >> Subject: Re: [RFC net-next] net: stmmac: should not modify RX
> >> descriptor when STMMAC resume
> >>
> >>
> >> On 22/04/2021 16:56, Jakub Kicinski wrote:
> >>> On Thu, 22 Apr 2021 04:53:08 +0000 Joakim Zhang wrote:
> >>>> Could you please help review this patch? It's really beyond my
> >>>> comprehension, why this patch would affect Tegra186 Jetson TX2 board?
> >>>
> >>> Looks okay, please repost as non-RFC.
> >>
> >>
> >> I still have an issue with a board not being able to resume from
> >> suspend with this patch. Shouldn't we try to resolve that first?
> >
> > Hi Jon,
> >
> > Any updates about this? Could I repost as non-RFC?
> 
> 
> Sorry no updates from my end. Again, I don't see how we can post this as it
> introduces a regression for us. I am sorry that I am not able to help more here,
> but we have done some extensive testing on the current mainline without your
> change and I don't see any issues with regard to suspend/resume. Hence, this
> does not appear to fix any pre-existing issues. It is possible that we are not
> seeing them.
> 
> At this point I think that we really need someone from Synopsys to help us
> understand that exact problem that you are experiencing so that we can
> ensure we have the necessary fix in place and if this is something that is
> applicable to all devices or not.

This patch only removes modification of Rx descriptors when STMMAC resume back, IMHO, it should not affect system suspend/resume function.
Do you have any idea about Joh's issue or any acceptable solution to fix the issue I met? Thanks a lot!

Best Regards,
Joakim Zhang
> Jon
> 
> --
> nvpublic