On Thu, Feb 06, 2025 at 07:16:25PM -0800, Yidong Zhang wrote: > > > On 2/6/25 18:19, Xu Yilun wrote: > > Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding. > > > > > > > > No need to detach a specific driver, remove all devices in the > > > > fpga-region. I imagine this could also be a generic flow for all PCI/e > > > > based FPGA cards. > > > > > > I see your point. Is there an existing example in current fpga driver for > > > PCI/e based cards? > > > > No. The fpga-region re-enumeration arch is still WIP, so no existing > > implementation. > > Got you. I can also help to test or provide feedback. > Actually, I had sent Nava my protype of using configfs for the non-OF > driver. He should have the updated patch soon. > > > > > > > > > We will need to talk to our management team and re-design our driver. > > > I think we have 2 approaches: > > > 1) Align with linux fpga, having one driver for both userPF and mgmtPF; or > > > > Don't get you. Linux FPGA doesn't require one driver for both PFs. > > I assume when you said "generic flow for removing all devices in > fpga-region" means that there is a single driver which use the fpga-region > callbacks to remove all devices and then re-progream the FPGA. > > On AMD V70 hardware, the userPF has different deviceid than the mgmtPF. > Thus, our current design is having 2 separate pcie drivers for each > different deviceid. > > Thus, in our current design, the fpga-region should be in the userPF driver > which has callbacks to remove all devices. But in mgmtPF, it is more like a A question, if the FPGA logic is cleared, does the userPF still exist on PCIe bus? > utility which only handles request from the userPF but it has the management > privilege. Usually, cloud vendors require the mgmtPF deployed in their > secured domain (can be a separate physical machine). I though mgmtPF & userPF are just 2 functions on one PCIe card, they are not? Then how the mgmtPF writes data to another physical machine and influence the userPF? Thanks, Yilun > > We can keep 2 drivers, one for userPF, one for mgmtPF. The userPF and mgmtPF > communicate each other via the communication channel because they can be > physically on different machine. > > Are you looking for us to upstream both of them together? > If yes, I still think that the fpga-region should be in the userPF driver. > The mgmtPF driver is still a utility driver. > > Please correct me if I am wrong.:) > > > > > > 2) find a different location (maybe driver/misc) for the version-pci driver, > > > because it is an utility driver, not need to be tied with fpga framework. > > > > I'm not the misc maintainer, but I assume in-tree utility driver + > > out-of-tree client driver is not generally welcomed. > > Great info! Thanks! I will have to discuss this with my team too. > > My understanding, so far based on your comments above, the drivers/fpga > prefer to use fpga-region ops to handle FPGA re-program changes. > > The current versal-pci driver is a utility driver. > The fpga-region should be within the userPF driver. > > We can try to make our userPF driver in-tree as well. But the current plan > is to do it later. > > If you prefer we do both of them together. I can talk to my team. > > Thanks, > David > > > > Thanks, > > Yilun > > > > > > > > Please let me know you thoughts. Which way is acceptable by you. > > > > > > Thanks, > > > David > > > > > > > > Thanks, > > > > Yilun > > > > > > > > > driver and allow the userPF driver re-enumerate all to match the new > > > > > hardware. > > > > > > > > > > I think my understanding is correct, it is doable. > > > > > > > > > > As long as we can keep our userPF driver as separate driver, the code change > > > > > won't be too big. > > > > > > > > > > > > > > > > > Thanks, > > > > > > Yilun
