On Fri, Oct 09, 2020 at 02:20:59PM +0800, Xu Yilun wrote: > Hi Greg: > > On Mon, Sep 28, 2020 at 09:19:00PM -0700, Moritz Fischer wrote: > > Hi Xu, > > > > On Tue, Sep 29, 2020 at 09:23:23AM +0800, Xu Yilun wrote: > > > Hi moritz: > > > > > > On Sun, Sep 27, 2020 at 04:36:47PM +0800, Xu Yilun wrote: > > > > Hi Greg, > > > > > > > > On Sun, Sep 27, 2020 at 09:54:01AM +0200, Greg KH wrote: > > > > > On Sun, Sep 27, 2020 at 03:37:54PM +0800, Xu Yilun wrote: > > > > > > Hi Greg, > > > > > > > > > > > > On Sun, Sep 27, 2020 at 07:51:08AM +0200, Greg KH wrote: > > > > > > > On Sat, Sep 26, 2020 at 12:22:19PM -0700, Moritz Fischer wrote: > > > > > > > > Hi Greg, > > > > > > > > > > > > > > > > On Sat, Sep 26, 2020 at 08:09:13AM +0200, Greg KH wrote: > > > > > > > > > On Sat, Sep 26, 2020 at 10:23:46AM +0800, Xu Yilun wrote: > > > > > > > > > > Hi greg, > > > > > > > > > > > > > > > > > > > > About the bus naming, I summarized some questions we've discussed to check > > > > > > > > > > with you. See inline. > > > > > > > > > > > > > > > > > > > > On Thu, Sep 24, 2020 at 10:27:00AM -0700, Moritz Fischer wrote: > > > > > > > > > > > Hi Xu, > > > > > > > > > > > > > > > > > > > > > > On Fri, Sep 25, 2020 at 12:59:57AM +0800, Xu Yilun wrote: > > > > > > > > > > > > Now the DFL device drivers could be made as independent modules and put > > > > > > > > > > > > in different subsystems according to their functionalities. So the name > > > > > > > > > > > > should be descriptive and unique in the whole kernel. > > > > > > > > > > > > > > > > > > > > > > > > The patch changes the naming of dfl bus related structures, functions, > > > > > > > > > > > > APIs and documentations. > > > > > > > > > > > > > > > > > > > > > > > > Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx> > > > > > > > > > > > > --- > > > > > > > > > > > > Documentation/ABI/testing/sysfs-bus-dfl | 15 -- > > > > > > > > > > > > Documentation/ABI/testing/sysfs-bus-fpga-dfl | 15 ++ > > > > > > > > > > > > MAINTAINERS | 2 +- > > > > > > > > > > > > drivers/fpga/dfl.c | 254 ++++++++++++++------------- > > > > > > > > > > > > drivers/fpga/dfl.h | 77 ++++---- > > > > > > > > > > > > 5 files changed, 184 insertions(+), 179 deletions(-) > > > > > > > > > > > > delete mode 100644 Documentation/ABI/testing/sysfs-bus-dfl > > > > > > > > > > > > create mode 100644 Documentation/ABI/testing/sysfs-bus-fpga-dfl > > > > > > > > > > > > > > > > > > > > > > > > diff --git a/Documentation/ABI/testing/sysfs-bus-dfl b/Documentation/ABI/testing/sysfs-bus-dfl > > > > > > > > > > > > deleted file mode 100644 > > > > > > > > > > > > index 23543be..0000000 > > > > > > > > > > > > --- a/Documentation/ABI/testing/sysfs-bus-dfl > > > > > > > > > > > > +++ /dev/null > > > > > > > > > > > > @@ -1,15 +0,0 @@ > > > > > > > > > > > > -What: /sys/bus/dfl/devices/dfl_dev.X/type > > > > > > > > > > > > -Date: Aug 2020 > > > > > > > > > > > > -KernelVersion: 5.10 > > > > > > > > > > > > -Contact: Xu Yilun <yilun.xu@xxxxxxxxx> > > > > > > > > > > > > -Description: Read-only. It returns type of DFL FIU of the device. Now DFL > > > > > > > > > > > > - supports 2 FIU types, 0 for FME, 1 for PORT. > > > > > > > > > > > > - Format: 0x%x > > > > > > > > > > > > - > > > > > > > > > > > > -What: /sys/bus/dfl/devices/dfl_dev.X/feature_id > > > > > > > > > > > > -Date: Aug 2020 > > > > > > > > > > > > -KernelVersion: 5.10 > > > > > > > > > > > > -Contact: Xu Yilun <yilun.xu@xxxxxxxxx> > > > > > > > > > > > > -Description: Read-only. It returns feature identifier local to its DFL FIU > > > > > > > > > > > > - type. > > > > > > > > > > > > - Format: 0x%x > > > > > > > > > > > > > > > > > > > > > > You're changing userland facing ABI. I think that's something to avoid, > > > > > > > > > > > please check with Greg on the rules since this hasn't been in a release yet. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > I'm going to change the name of bus stuff for other subsystems, to be > > > > > > > > > > aligned, I also consider change the bus_type.name and dfl dev_name. But > > > > > > > > > > it will cause the changing of user ABIs. No user case for these user ABI > > > > > > > > > > now cause they are just queued, is it good I change them? > > > > > > > > > > > > > > > > > > Why change the user name here? No need for that, right? Unless you > > > > > > > > > really want to, and think that no one will notice. If so, fine, change > > > > > > > > > them :) > > > > > > > > > > > > > > > > Let's leave it as is -- An FPGA is one possible implementation and as for > > > > > > > > other buses, you wouldn't call it fpga-usb or usb-fpga just because the > > > > > > > > USB bus is implemented in an FPGA if it behaves like a normal USB bus. > > > > > > > > Having an ASIC based DFL bus show up under dfl-fpga / fpga-dfl in sysfs > > > > > > > > would be super confusing. > > > > > > > > I thought we have consensus that "dfl" could be used out of fpga domain. > > > > And we are all good that we keep the user ABIs & the bus name - "dfl", so "dfl" > > > > is good as a global name from linux user's point of view, is it? > > > > > > > > But why we reject the "dfl" in kernel code domain? I thought it is very > > > > similar situation. > > > > > > > > > > > > I think we have 2 options, to make the dfl self-consistent: > > > > > > > > 1. "dfl-fpga" for everything - bus name, user ABIs, structures & APIs for > > > > other kernel subsystems. Then we lose the chance to support ASIC based DFL, > > > > it would be hard if we change user ABIs later. > > > > > > > > 2. "dfl" for everything. > > > > > > > > BTW, no ASIC based DFL devices in kernel today. > > > > > > > > I fully understand the word "naming is hard" now, help me :) > > > > > > Seems now we have different opinions on this: > > > > > > - Hao thinks self-consistent is important to dfl framework. > > Agreed. I mostly care about userspace facing ABI, though. > > > > > - "dfl" for everything seems not preferable to Greg. > > Maybe now that we re-explained, we can take another look at that? > > > > > - From your previous mail, I assume you prefer to keep the bus name as "dfl" > > > but change the stuff for other subsystem, is it? > > > > I mostly think we should keep DFL generic where it touches userspace and > > defines ABI, since we cannot change it afterwards. > > > > I rest my point with the bus being independent of FPGAs despite the FPGA > > being the (currently) only user. > > > > > So I got a little stuck here. > > > > > > Do you think "dfl-fpga" for everything would be an acceptable solution > > > for you? > > > > I just think it doesn't make a lot of sense to call it fpga-dfl or > > dfl-fpga. But if everyone else disagrees ... naming is hard :-) > > Hi Greg, > > We made some re-explanation why "dfl" could be independent of the fpga > subsystem in this mail thread. And now the name "dfl" for all bus stuff is good > to Moritz, Hao & Yilun. Could you help take another look at this? What is "this"? I don't see any fpga patches in my inbox anywhere...
