iommu: qcom-smmu: handle running in el2

We only need to configure the SMMU when running in EL1. In EL2 the
hypervisor isn't running so peripherals can just do DMA as they wish.

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
diff --git a/drivers/iommu/qcom-hyp-smmu.c b/drivers/iommu/qcom-hyp-smmu.c
index 7e07487..c1b95bc 100644
--- a/drivers/iommu/qcom-hyp-smmu.c
+++ b/drivers/iommu/qcom-hyp-smmu.c
@@ -91,6 +91,8 @@
 	phys_addr_t base;
 	struct list_head devices;
 	struct udevice *dev;
+	/* SMMU is not needed when running in EL2 */
+	bool disable;
 
 	/* Read-once config */
 	int num_cb;
@@ -277,6 +279,9 @@
 	if (WARN_ON(!priv))
 		return -EINVAL;
 
+	if (priv->disable)
+		return 0;
+
 	mdev = alloc_dev(dev);
 	if (IS_ERR(mdev) && PTR_ERR(mdev) != -EEXIST) {
 		printf("%s: %s Couldn't create mmu context\n", __func__,
@@ -348,6 +353,8 @@
 	priv->base = dev_read_addr(dev);
 	INIT_LIST_HEAD(&priv->devices);
 
+	priv->disable = current_el() > 1;
+
 	/* Read SMMU config */
 	val = gr0_readl(priv, ARM_SMMU_GR0_ID0);
 	priv->num_smr = FIELD_GET(ARM_SMMU_ID0_NUMSMRG, val);