Hi Laurent and Omar, Laurent Pinchart wrote: > On Friday 25 March 2011 20:37:55 Ramirez Luna, Omar wrote: >> On Fri, Mar 25, 2011 at 10:13 AM, Sakari Ailus >> >> <sakari.ailus@xxxxxxxxxxxxxxxxxxxxxxxxxx> wrote: >>> Hi, >>> >>> This patchset is aimed to fix a problem in arch_iommu implementation >>> references. When an actual arch_iommu implementation is not loaded while >>> iommu_get() is being called results to a kernel oops, as well as >>> removing an arch_iommu implementation which is in use. >> >> How about fixing the dependency instead? Right now iommu2 depends on >> iommu because of the calls to >> install_iommu_arch/uninstall_iommu_arch... we should change that >> dependency to iommu depend on iommu2. Something like iommu (plat) >> querying iommu2 (mach) for devices to install. > > The reason why iommu depends on iommu2 and not the other way around is because > several mach-specific iommu implementations should be able to coexist in the > same kernel. The right one should be loaded at runtime. > > I think that Sakari's patches correcty fix the problems he noticed. However, > they won't fix one basic issue, which is that the iommu2 module won't be > automatically pulled in when the omap3isp module is loaded. The omap3isp > driver will then fail to probe the device. That's better than crashing though. One option would be to specify the name of the module in the platform data and request_module() that in omap_iommu_probe(). This would solve the issue, not sure how pretty is this though. In a generic case there would have to be a list of modules implementing iommu in the platform data. > One possible solution for that is to turn the tristate option for iommu2 into > a bool option. I've also read a couple of times that the kernel provides a > standard iommu API. Maybe switching to it would help. That would solve it as well, but having it as a module would be nice, too. Regards, -- Sakari Ailus sakari.ailus@xxxxxxxxxxxxxxxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
