Am Mon, 7 Oct 2024 09:15:43 -0300 schrieb Jason Gunthorpe <jgg@xxxxxxxxxx>: > On Sun, Oct 06, 2024 at 09:40:00AM +0200, H. Nikolaus Schaller wrote: > > Hi, > > > > I found that the camera on our OMAP3 based system (GTA04) stopped > > working with v6.8-rc1. There was no bug in the camera driver but > > the OMAP3 ISP (image signal processor) emits > > > > [ 14.963684] omap3isp 480bc000.isp: failed to create ARM IOMMU > > mapping [ 15.010192] omap3isp 480bc000.isp: unable to attach to > > IOMMU [ 15.023376] omap3isp 480bc000.isp: isp_xclk_set_rate: > > cam_xclka set to 24685714 Hz (div 7) [ 15.065399] omap3isp: probe > > of 480bc000.isp failed with error -12 > > > > Deeper analyses lead to this patch breaking operation. It is not > > fixed up to v6.12-rc1. > > > > What seems to happen (in 6.8-rc1 code): > > > > - omap_iommu_probe() passes &omap_iommu_ops to > > iommu_device_register() > > - iommu_device_register() stores the ops in iommu->ops (only) > > - __iommu_probe_device tries to read the ops from some fw_spec but > > not iommu->ops > > Maybe like this? > > @@ -1233,6 +1233,12 @@ static int omap_iommu_probe(struct > platform_device *pdev) err = iommu_device_register(&obj->iommu, > &omap_iommu_ops, &pdev->dev); if (err) > goto out_sysfs; > + /* > + * omap has a DT reprensetation but can't use the > common DT > + * code. Setting fwnode to NULL causes probe to be > called for > + * every device. > + */ > + obj->iommu.fwnode = NULL; > obj->has_iommu_driver = true; > } > hmm, that looks nice for a regression fix. Does it make sense to adopt dt so that the common code can be used to ease future maintenance? Regards, Andreas