> -----Original Message----- > From: Joakim Zhang <qiangqing.zhang@xxxxxxx> > Sent: 2021年3月31日 15:44 > To: Jon Hunter <jonathanh@xxxxxxxxxx> > Cc: netdev@xxxxxxxxxxxxxxx; Linux Kernel Mailing List > <linux-kernel@xxxxxxxxxxxxxxx>; linux-tegra <linux-tegra@xxxxxxxxxxxxxxx>; > Jakub Kicinski <kuba@xxxxxxxxxx> > Subject: RE: Regression v5.12-rc3: net: stmmac: re-init rx buffers when mac > resume back > > > > -----Original Message----- > > From: Jon Hunter <jonathanh@xxxxxxxxxx> > > Sent: 2021年3月30日 20:51 > > To: Joakim Zhang <qiangqing.zhang@xxxxxxx> > > Cc: netdev@xxxxxxxxxxxxxxx; Linux Kernel Mailing List > > <linux-kernel@xxxxxxxxxxxxxxx>; linux-tegra > > <linux-tegra@xxxxxxxxxxxxxxx>; Jakub Kicinski <kuba@xxxxxxxxxx> > > Subject: Re: Regression v5.12-rc3: net: stmmac: re-init rx buffers > > when mac resume back > > > > > > > > On 25/03/2021 08:12, Joakim Zhang wrote: > > > > ... > > > > >>>>> You mean one of your boards? Does other boards with STMMAC can > > >>>>> work > > >>>> fine? > > >>>> > > >>>> We have two devices with the STMMAC and one works OK and the > > >>>> other > > >> fails. > > >>>> They are different generation of device and so there could be > > >>>> some architectural differences which is causing this to only be > > >>>> seen on one > > device. > > >>> It's really strange, but I also don't know what architectural > > >>> differences could > > >> affect this. Sorry. > > > > > > I realised that for the board which fails after this change is made, > > it has the IOMMU enabled. The other board does not at the moment > > (although work is in progress to enable). If I add > > 'iommu.passthrough=1' to cmdline for the failing board, then it works > > again. So in my case, the problem is linked to the IOMMU being enabled. > > > > Does you platform enable the IOMMU? > > Hi Jon, > > There is no IOMMU hardware available on our boards. But why IOMMU would > affect it during suspend/resume, and no problem in normal mode? One more add, I saw drivers/iommu/tegra-gart.c(not sure if is this) support suspend/resume, is it possible iommu resume back after stmmac? Best Regards, Joakim Zhang > Best Regards, > Joakim Zhang > > Thanks > > Jon > > > > -- > > nvpublic
