On Mon, 23 Jul 2018 17:40:02 -0700 Sinan Kaya <okaya@xxxxxxxxxx> wrote: > On 7/23/2018 5:13 PM, Alex Williamson wrote: > > + * The NVMe specification requires that controllers support PCIe FLR, but > > + * but some Samsung SM961/PM961 controllers fail to recover after FLR (-1 > > + * config space) unless the device is quiesced prior to FLR. > > Does disabling the memory bit in PCI config space as part of the FLR > reset function help? (like the very first thing) No, it does not. I modified this to only clear PCI_COMMAND_MEMORY and call pcie_flr(), the Samsung controller dies just as it did previously. > Can we do that in the pcie_flr() function to cover other endpoint types > that might be pushing traffic while code is trying to do a reset? Do you mean PCI_COMMAND_MASTER rather than PCI_COMMAND_MEMORY? I tried that too, it doesn't work either. I'm not really sure the theory behind clearing memory, clearing busmaster to stop DMA seems like a sane thing to do, but doesn't help here. Thanks, Alex
