Ping? On 17/09/2018 17:05, Alexey Kardashevskiy wrote: > Ping? > > The problem is still there... > > > On 24/08/2018 13:04, Alexey Kardashevskiy wrote: >> >> >> On 09/08/2018 14:41, Alexey Kardashevskiy wrote: >>> >>> >>> On 25/07/2018 19:50, Alexey Kardashevskiy wrote: >>>> I am trying to pass through a 3D controller: >>>> [0302]: NVIDIA Corporation GV100GL [Tesla V100 SXM2] [10de:1db1] (rev a1) >>>> >>>> which has a quite unique feature as coherent memory directly accessible >>>> from a POWER9 CPU via an NVLink2 transport. >>>> >>>> So in addition to passing a PCI device + accompanying NPU devices, >>>> we will also be passing the host physical address range as it is done >>>> on the bare metal system. >>>> >>>> The memory on the host is presented as: >>>> >>>> === >>>> [aik@yc02goos ~]$ lsprop /proc/device-tree/memory@42000000000 >>>> ibm,chip-id 000000fe (254) >>>> device_type "memory" >>>> compatible "ibm,coherent-device-memory" >>>> reg 00000420 00000000 00000020 00000000 >>>> linux,usable-memory >>>> 00000420 00000000 00000000 00000000 >>>> phandle 00000726 (1830) >>>> name "memory" >>>> ibm,associativity >>>> 00000004 000000fe 000000fe 000000fe 000000fe >>>> === >>>> >>>> and the host does not touch it as the second 64bit value of >>>> "linux,usable-memory" - the size - is null. Later on the NVIDIA driver >>>> trains the NVLink2 and probes this memory and this is how it becomes >>>> onlined. >>>> >>>> In the virtual environment I am planning on doing the same thing, >>>> however there is a difference in 64bit DMA handling. The powernv >>>> platform uses a PHB3 bypass mode and that just works but >>>> the pseries platform uses DDW RTAS API to achieve the same >>>> result and the problem with this is that we need a huge DMA >>>> window to start from zero (because this GPU supports less than >>>> 50bits for DMA address space) and cover not just present memory >>>> but also this new coherent memory. >>>> >>>> >>>> This is based on sha1 >>>> d72e90f3 Linus Torvalds "Linux 4.18-rc6". >>>> >>>> Please comment. Thanks. >>> >>> >>> Ping? >> >> >> Ping? >> >>> >>> >>>> >>>> >>>> >>>> Alexey Kardashevskiy (3): >>>> powerpc/pseries/iommu: Allow dynamic window to start from zero >>>> powerpc/pseries/iommu: Force default DMA window removal >>>> powerpc/pseries/iommu: Use memory@ nodes in max RAM address >>>> calculation >>>> >>>> arch/powerpc/platforms/pseries/iommu.c | 77 ++++++++++++++++++++++++++++++---- >>>> 1 file changed, 70 insertions(+), 7 deletions(-) >>>> >>> >> > -- Alexey
