On Wed, Nov 28, 2012 at 02:48:32PM +0100, Hiroshi Doyu wrote: [...]
From: Hiroshi Doyu hdoyu@nvidia.com Date: Wed, 28 Nov 2012 14:47:04 +0200 Subject: [PATCH 1/1] ARM: tegra: bus_notifier registers IOMMU devices
platform_bus notifier registers IOMMU devices if dma-window is specified.
Its format is: dma-window = <"start" "size">; ex) dma-window = <0x12345000 0x8000>;
Signed-off-by: Hiroshi Doyu hdoyu@nvidia.com
arch/arm/mach-tegra/board-dt-tegra30.c | 40 ++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+)
diff --git a/arch/arm/mach-tegra/board-dt-tegra30.c b/arch/arm/mach-tegra/board-dt-tegra30.c index a2b6cf1..570d718 100644 --- a/arch/arm/mach-tegra/board-dt-tegra30.c +++ b/arch/arm/mach-tegra/board-dt-tegra30.c @@ -30,9 +30,11 @@ #include <linux/of_fdt.h> #include <linux/of_irq.h> #include <linux/of_platform.h> +#include <linux/of_iommu.h> #include <asm/mach/arch.h> #include <asm/hardware/gic.h> +#include <asm/dma-iommu.h> #include "board.h" #include "clock.h" @@ -86,10 +88,48 @@ static __initdata struct tegra_clk_init_table tegra_dt_clk_init_table[] = { { NULL, NULL, 0, 0}, }; +#ifdef CONFIG_ARM_DMA_USE_IOMMU +static int tegra_iommu_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))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;- }
- return NOTIFY_DONE;
+} +#else +#define tegra_iommu_device_notifier NULL +#endif
+static struct notifier_block tegra_iommu_device_nb = {
- .notifier_call = tegra_iommu_device_notifier,
+};
You don't need this extra protection since you use IS_ENABLED below and these are all static variables. The whole point of IS_ENABLED is to allow full compile coverage while leaving it up to the compiler to eliminate dead code.
Thierry