iommu: add a connect op
Add an optional iommu callback to be invoked before a device probes.
This can be used to configure the IOMMU in preparation for the device
(e.g. by allocating a context bank)
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
diff --git a/drivers/iommu/iommu-uclass.c b/drivers/iommu/iommu-uclass.c
index 98731d5..6babc0e3 100644
--- a/drivers/iommu/iommu-uclass.c
+++ b/drivers/iommu/iommu-uclass.c
@@ -77,6 +77,7 @@
{
struct ofnode_phandle_args args;
struct udevice *dev_iommu;
+ const struct iommu_ops *ops;
int i, count, ret = 0;
count = dev_count_phandle_with_args(dev, "iommus",
@@ -98,6 +99,16 @@
return ret;
}
dev->iommu = dev_iommu;
+
+ if (dev->parent && dev->parent->iommu == dev_iommu)
+ continue;
+
+ ops = device_get_ops(dev->iommu);
+ if (ops && ops->connect) {
+ ret = ops->connect(dev);
+ if (ret)
+ return ret;
+ }
}
#if CONFIG_IS_ENABLED(PCI)
diff --git a/include/iommu.h b/include/iommu.h
index cf9719c..b8ba0b8 100644
--- a/include/iommu.h
+++ b/include/iommu.h
@@ -5,6 +5,15 @@
struct iommu_ops {
/**
+ * init() - Connect a device to it's IOMMU, called before probe()
+ * The iommu device can be fetched through dev->iommu
+ *
+ * @iommu_dev: IOMMU device
+ * @dev: Device to connect
+ * @return 0 if OK, -errno on error
+ */
+ int (*connect)(struct udevice *dev);
+ /**
* map() - map DMA memory
*
* @dev: device for which to map DMA memory