Wesley, I'm going to suggest you send patches to me before sending them to the community until you have a better handle of the tools and process. The subject suggests you have 11 other patches in this series so you've mishandled the tools. On 2018-09-26 11:57 p.m., Wesley.Sheng@xxxxxxxxxxxxx wrote: > After submit a Firmware Download (Download sub-command) MRPC > command, Switchtec firmware refuses to response any management > EP's BAR access until current flash programming finished. > During this time, a READ TLP to the gas area in the BAR of the > management EP will complete with significant delay like more than > 10ms. > It's a Switchtec firmware limitation that READ requests cannot get > prompt service during firmware download. > The delayed completion of READ TLP would be a problem on some system > which is sensitive to READ timeout. > Current driver check status immediately after submit a MRPC command, > which triggers READ TLP to the gas area in the BAR of the management EP. > Also, other processes or functions, like NTB, would also trigger READ TLP by > accessing the GAS. > To avoid this, the immediate check of status is removed in this patch, and > driver delays the status check to the occurrence of MSIx or MRPC timeout. > In the meantime, user must not initiate any gas access during a firmware > download. > Also, any process that issues MRPC command will be affected by the delay > in this patch. > However, this is only a software workaround to the READ issue in firmware > download. A complete fix of this should happen in firmware. > > Note: For NTB function, the memory window access is handled by Switchtec > hardware. So it's not affected by this firmware limitation. But the other GAS > access which is handled by Switchtec firmware is are affected by this firmware > limitation. The commit message is poorly formatted/wrapped and with all due respect, I think the grammar needs a lot of work. > --- > drivers/pci/switch/switchtec.c | 4 ---- > 1 file changed, 4 deletions(-) > > diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c index 4591f15..b759228 100644 > --- a/drivers/pci/switch/switchtec.c > +++ b/drivers/pci/switch/switchtec.c > @@ -142,10 +142,6 @@ static void mrpc_cmd_submit(struct switchtec_dev *stdev) > stuser->data, stuser->data_len); > iowrite32(stuser->cmd, &stdev->mmio_mrpc->cmd); > > - stuser->status = ioread32(&stdev->mmio_mrpc->status); > - if (stuser->status != SWITCHTEC_MRPC_STATUS_INPROGRESS) > - mrpc_complete_cmd(stdev); > - > schedule_delayed_work(&stdev->mrpc_timeout, > msecs_to_jiffies(500)); > } The change itself looks good. Logan
