Hi Joerg, Am Freitag, 31. M?rz 2017, 16:30:24 CEST schrieb Joerg Roedel: > From: Joerg Roedel <jroedel at suse.de> > > Register hardware IOMMUs seperatly with the iommu-core code > and add a sysfs representation of the iommu topology. > > Signed-off-by: Joerg Roedel <jroedel at suse.de> In general works, and I still keep a working iommu-based display :-) I can also see my two vop iommus under /sys/class/iommu now. Links in the devices subdirectory do not work though, see below: > --- > drivers/iommu/rockchip-iommu.c | 30 ++++++++++++++++++++++++++++-- > 1 file changed, 28 insertions(+), 2 deletions(-) > > diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c > index 9afcbf7..36d0890 100644 > --- a/drivers/iommu/rockchip-iommu.c > +++ b/drivers/iommu/rockchip-iommu.c > @@ -1054,6 +1056,10 @@ static int rk_iommu_add_device(struct device *dev) > if (ret) > goto err_remove_device; > > + iommu = rk_iommu_from_dev(dev); > + if (iommu) > + iommu_device_link(&iommu->iommu, dev); > + It looks like the iommu association can very well run before the iommu actually probes, via the bus_set_iommu and which happens on my veyron-pinky device). Thus iommu is NULL, as platform_set_drvdata in probe hasn't run yet and the link is never created. [ 0.034180] iommu: Adding device ff930000.vop to group 0 [ 0.034198] rk_iommu_from_dev: found iommu ff930300.iommu for ff930000.vop with data at (null) [ 0.034209] rk_iommu_add_device: rk_iommu_from_dev returned (null) for ff930000.vop [ 0.034232] iommu: Adding device ff940000.vop to group 1 [ 0.034247] rk_iommu_from_dev: found iommu ff940300.iommu for ff940000.vop with data at (null) [ 0.034258] rk_iommu_add_device: rk_iommu_from_dev returned (null) for ff940000.vop [ 0.034342] rk_iommu_probe: set_drvdata for ff930300.iommu at ee2c7a10 [ 0.034411] rk_iommu_probe: set_drvdata for ff940300.iommu at ee2c7c10 [ 7.326395] rk_iommu_from_dev: found iommu ff930300.iommu for ff930000.vop with data at ee2c7a10 Not sure what the proper solution is though. Heiko
