On Sun, 27 Apr 2014 20:17:48 +0200, Arnd Bergmann wrote: > On Sunday 27 April 2014 13:07:47 Shaik Ameer Basha wrote: > > @@ -542,14 +592,41 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev) > > } > > } > > > > + /* Relation between master and System MMU is 1:1. */ > > + node = of_parse_phandle(dev->of_node, "mmu-masters", 0); > > + if (node) { > > + struct platform_device *master = of_find_device_by_node(node); > > + > > + if (!master) { > > + dev_err(dev, "%s: mmu-master '%s' not found\n", > > + __func__, node->name); > > + return -EINVAL; > > + } > > + > > + if (master->dev.archdata.iommu != NULL) { > > + dev_err(dev, "%s: '%s' is master of other MMU\n", > > + __func__, node->name); > > + return -EINVAL; > > + } > > + > > + /* > > + * archdata.iommu will be initialized with exynos_iommu_client > > + * in sysmmu_hook_driver_register(). > > + */ > > + master->dev.archdata.iommu = dev; > > + } > > I think parsing of generic properties like this shouldn't be done > by the individual driver. It belongs into core iommu code and should > be done when the devices are probed. > > > + > > +static struct notifier_block sysmmu_notifier = { > > + .notifier_call = &sysmmu_hook_driver_register, > > +}; > > + > > +static int __init exynos_iommu_prepare(void) > > +{ > > + static bool registered = false; > > + int ret; > > + > > + if (registered) > > + return 0; > > + > > + ret = bus_register_notifier(&platform_bus_type, &sysmmu_notifier); > > + if (!ret) > > + registered = true; > > + else > > + pr_err("Failed to register sysmmu_notifier\n"); > > + > > + return ret; > > +} > > This also means we should not have notifiers. Put it into core code to > make sure all IOMMUs are handled the same way. > Ok. Thank you for addressing that. I am also very interested in the discussion about it in the different thread. KyongHo -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html