On Fri, Nov 30, 2012 at 02:19:51PM +0200, Hiroshi Doyu wrote:
> Most of platform devices are IOMMU'able in Tegra30 SoC. Registering
> all IOMMU'able devices manually isn't nice. This patch allows
> platform bus_notifier to register IOMMU devices. Map info can be
> passed from DT. Info format is:
> 
>   dma-window = <0 0x40000000>;
> 
> TODO:
> A map can be shared with mutiple devices. This info also could be
> passed from DT or default map can be set in advance.
> 
> Signed-off-by: Hiroshi Doyu <[email protected]>
> ---
>  drivers/iommu/tegra-smmu.c |   45 
> +++++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 44 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
> index 25c1210..1c49af9 100644
> --- a/drivers/iommu/tegra-smmu.c
> +++ b/drivers/iommu/tegra-smmu.c
> @@ -38,6 +38,7 @@
>  
>  #include <asm/page.h>
>  #include <asm/cacheflush.h>
> +#include <asm/dma-iommu.h>
>  
>  enum smmu_hwgrp {
>       HWGRP_AFI,
> @@ -1273,9 +1274,51 @@ static struct platform_driver tegra_smmu_driver = {
>       },
>  };
>  
> +static int tegra_smmu_device_notifier(struct notifier_block *nb,
> +                                   unsigned long event, void *_dev)
> +{
> +     struct dma_iommu_mapping *map = NULL;
> +     struct device *dev = _dev;
> +     dma_addr_t base;
> +     size_t size;
> +     int err;
> +
> +     switch (event) {
> +     case BUS_NOTIFY_ADD_DEVICE:
> +             err = of_get_dma_window(dev->of_node, NULL, 0, NULL, &base,
> +                                     &size);
> +             if (!err)
> +                     map = arm_iommu_create_mapping(&platform_bus_type,
> +                                                    base, size, 0);
> +             if (IS_ERR_OR_NULL(map))
> +                     break;
> +             if (arm_iommu_attach_device(dev, map)) {
> +                     arm_iommu_release_mapping(map);
> +                     dev_err(dev, "Failed to attach %s\n", dev_name(dev));
> +             }
> +             dev_dbg(dev, "Attached %s to map %p\n", dev_name(dev), map);
> +             break;
> +     default:
> +             break;
> +     }
> +     return NOTIFY_DONE;
> +}
> +
> +static struct notifier_block tegra_smmu_device_nb = {
> +     .notifier_call = tegra_smmu_device_notifier,
> +};
> +
>  static int __devinit tegra_smmu_init(void)
>  {
> -     return platform_driver_register(&tegra_smmu_driver);
> +     int err;
> +
> +     err = platform_driver_register(&tegra_smmu_driver);
> +     if (err)
> +             return err;
> +     if (IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU))
> +             bus_register_notifier(&platform_bus_type,
> +                                   &tegra_smmu_device_nb);

Where do you call the bus_unregister_notifier?


        Joerg


--
To unsubscribe from this list: send the line "unsubscribe linux-tegra" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to