On Tue, 9 Aug 2022 17:08:25 +0100 Jonathan Cameron <jonathan.came...@huawei.com> wrote:
> On Tue, 9 Aug 2022 21:07:06 +0800 > Bobo WL <lmw.b...@gmail.com> wrote: > > > Hi Jonathan > > > > Thanks for your reply! > > > > On Mon, Aug 8, 2022 at 8:37 PM Jonathan Cameron > > <jonathan.came...@huawei.com> wrote: > > > > > > Probably not related to your problem, but there is a disconnect in QEMU / > > > kernel assumptionsaround the presence of an HDM decoder when a HB only > > > has a single root port. Spec allows it to be provided or not as an > > > implementation choice. > > > Kernel assumes it isn't provide. Qemu assumes it is. > > > > > > The temporary solution is to throw in a second root port on the HB and not > > > connect anything to it. Longer term I may special case this so that the > > > particular > > > decoder defaults to pass through settings in QEMU if there is only one > > > root port. > > > > > > > You are right! After adding an extra HB in qemu, I can create a x1 > > region successfully. > > But have some errors in Nvdimm: > > > > [ 74.925838] Unknown online node for memory at 0x10000000000, assuming > > node 0 > > [ 74.925846] Unknown target node for memory at 0x10000000000, assuming > > node 0 > > [ 74.927470] nd_region region0: nmem0: is disabled, failing probe > > Ah. I've seen this one, but not chased it down yet. Was on my todo list to > chase > down. Once I reach this state I can verify the HDM Decode is correct which is > what > I've been using to test (Which wasn't true until earlier this week). > I'm currently testing via devmem, more for historical reasons than because it > makes > that much sense anymore. *embarassed cough*. We haven't fully hooked the LSA up in qemu yet. I'd forgotten that was still on the todo list. I don't think it will be particularly hard to do and will take a look in next few days. Very very indirectly this error is causing a driver probe fail that means that we hit a code path that has a rather odd looking check on NDD_LABELING. Should not have gotten near that path though - hence the problem is actually when we call cxl_pmem_get_config_data() and it returns an error because we haven't fully connected up the command in QEMU. Jonathan > > > > > And x4 region still failed with same errors, using latest cxl/preview > > branch don't work. > > I have picked "Two CXL emulation fixes" patches in qemu, still not working. > > > > Bob
